Sample records for central tropical pacific
-
A decadal tropical Pacific condition unfavorable to central Pacific El Niño
NASA Astrophysics Data System (ADS)
Zhong, Wenxiu; Zheng, Xiao-Tong; Cai, Wenju
2017-08-01
The frequency of central Pacific (CP) El Niño events displays strong decadal variability but the associated dynamics are unclear. The Interdecadal Pacific Oscillation (IPO) and the tropical Pacific decadal variability (TPDV) are two dominant modes of tropical Pacific decadal variability that can interact with high-frequency activities. Using a 500 year control integration from the Geophysical Fluid Dynamics Laboratory Earth System Model, we find that the difference in mean state between the low-frequency and high-frequency CP El Niño periods is similar to the decadal background condition concurrently contributed by a negative IPO and a positive TPDV. This decadal state features strengthened trade winds west of the International Date Line and anomalous cool sea surface temperatures across the central tropical Pacific. As such, positive zonal advection feedback is difficult to be generated over the central to western tropical Pacific during the CP El Niño developing season, resulting in the low CP El Niño frequency.
-
Rare Central Pacific El Niño Events Caused by Interdecadal Tropical Pacific Variability
NASA Astrophysics Data System (ADS)
Zhong, Wenxiu; Zheng, Xiaotong; Cai, Wenju
2017-04-01
The frequency of Central Pacific (CP) El Niño events displays strong decadal-variability but the associated dynamics is still not clear. The Inter-decadal Pacific Oscillation (IPO) and the Tropical Pacific Decadal Variability (TPDV) are two dominant modes of the Pacific low-frequency variability that can modify high-frequency behaviors. Using a 500-year control integration of Geophysical Fluid Dynamics Laboratory Earth System Model simulation, we find that the mean state, determined by the two independent modes of tropical Pacific decadal variability, strongly affects CP El Niño frequency and the associated developing processes. A positive TPDV features a shallow thermocline and cool sea surface temperature anomalies (SSTAs) across the central-to-western tropical Pacific, and a negative IPO features cool SSTAs and strong trade winds along the equatorial Pacific. The combination of a positive TPDV and a negative IPO generates a decadal mean state, in which the climatological zonal temperature gradient is reduced, equatorward and westward current anomalies are harder to be generated over the central-to-western tropical Pacific, resulting in the lack of CP El Niño.
-
A warming tropical central Pacific dries the lower stratosphere
NASA Astrophysics Data System (ADS)
Ding, Qinghua; Fu, Qiang
2018-04-01
The amount of water vapor in the tropical lower stratosphere (TLS), which has an important influence on the radiative energy budget of the climate system, is modulated by the temperature variability of the tropical tropopause layer (TTL). The TTL temperature variability is caused by a complex combination of the stratospheric quasi-biennial oscillation (QBO), tropospheric convective processes in the tropics, and the Brewer-Dobson circulation (BDC) driven by mid-latitude and subtropical atmospheric waves. In 2000, the TLS water vapor amount exhibited a stepwise transition to a dry phase, apparently caused by a change in the BDC. In this study, we present observational and modeling evidence that the epochal change of water vapor between the periods of 1992-2000 and 2001-2005 was also partly caused by a concurrent sea surface temperature (SST) warming in the tropical central Pacific. This SST warming cools the TTL above by enhancing the equatorial wave-induced upward motion near the tropopause, which consequently reduces the amount of water vapor entering the stratosphere. The QBO affects the TLS water vapor primarily on inter-annual timescales, whereas a classical El Niño southern oscillation (ENSO) event has small effect on tropical mean TLS water vapor because its responses are longitudinally out of phase. This study suggests that the tropical central Pacific SST is another driver of TLS water vapor variability on inter-decadal timescales and the tropical SST changes could contribute to about 30% of the step-wise drop of the lower stratospheric water vapor from 1992-2000 to 2001-2005.
-
NASA Astrophysics Data System (ADS)
Nurhati, I. S.; Cobb, K.; Di Lorenzo, E.
2011-12-01
Accurate forecasts of regional climate changes in many regions of the world largely depend on quantifying anthropogenic trends in tropical Pacific climate against its rich background of interannual to decadal-scale climate variability. However, the strong natural climate variability combined with limited instrumental climate datasets have obscured potential anthropogenic climate signals in the region. Here, we present coral-based sea-surface temperature (SST) and salinity proxy records over the 20th century (1898-1998) from the central tropical Pacific - a region sensitive to El Niño-Southern Oscillation (ENSO) whose variability strongly impacts the global climate. The SST and salinity proxy records are reconstructed via coral Sr/Ca and the oxygen isotopic composition of seawater (δ18Osw), respectively. On interannual (2-7yr) timescales, the SST proxy record tracks both eastern- and central-Pacific flavors of ENSO variability (R=0.65 and R=0.67, respectively). Interannual-scale salinity variability in our coral record highlights profound differences in precipitation and ocean advections during the two flavors of ENSO. On decadal (8yr-lowpassed) timescales, the central tropical Pacific SST and salinity proxy records are controlled by different sets of dynamics linked to the leading climate modes of North Pacific climate variability. Decadal-scale central tropical Pacific SST is highly correlated to the recently discovered North Pacific Gyre Oscillation (NPGO; R=-0.85), reflecting strong dynamical links between the central Pacific warming mode and extratropical decadal climate variability. Whereas decadal-scale salinity variations in the central tropical Pacific are significantly correlated with the Pacific Decadal Oscillation (PDO; R=0.54), providing a better understanding on low-frequency salinity variability in the region. Having characterized natural climate variability in this region, the coral record shows a +0.5°C warming trend throughout the last century
-
Nath, Debashis; Chen, Wen; Graf, Hans-F; Lan, Xiaoqing; Gong, Hainan; Nath, Reshmita; Hu, Kaiming; Wang, Lin
2016-02-12
Drawn from multiple reanalysis datasets, an increasing trend and westward shift in the number of Potential Vorticity intrusion events over the Pacific are evident. The increased frequency can be linked to a long-term trend in upper tropospheric equatorial westerly wind and subtropical jets during boreal winter to spring. These may be resulting from anomalous warming and cooling over the western Pacific warm pool and the tropical eastern Pacific, respectively. The intrusions brought dry and ozone rich air of stratospheric origin deep into the tropics. In the tropical upper troposphere, interannual ozone variability is mainly related to convection associated with El Niño/Southern Oscillation. Zonal mean stratospheric overturning circulation organizes the transport of ozone rich air poleward and downward to the high and midlatitudes leading there to higher ozone concentration. In addition to these well described mechanisms, we observe a long-term increasing trend in ozone flux over the northern hemispheric outer tropical (10-25°N) central Pacific that results from equatorward transport and downward mixing from the midlatitude upper troposphere and lower stratosphere during PV intrusions. This increase in tropospheric ozone flux over the Pacific Ocean may affect the radiative processes and changes the budget of atmospheric hydroxyl radicals.
-
Medieval Aridity in the Central Tropical Pacific
NASA Astrophysics Data System (ADS)
Higley, M. C.; Conroy, J. L.; Schmitt, S.
2016-12-01
Reconstructing last millennium hydroclimate history in the tropical Pacific requires continuous, high temporal resolution archives of past moisture balance. Such records remain rare, particularly in the central tropical Pacific (CTP), where to date only one 1300-year terrestrial record of hydroclimate is available. Here we present a new brackish lake sediment record from Kiritimati Island (1.9° N, 157.4° W). 2000 years of geochemical and sedimentological data indicate centennial periods of fresher and more saline lake water. An episode of increased microbial mat development and gypsum precipitation marks the period 900 to 1250 CE, coincident with the Medieval Climate Anomaly (MCA), indicating a period of enhanced salinity and extended aridity. A shift from gypsum and microbial mats to carbonate sediment at the transition between the MCA and the Little Ice Age (LIA) supports the hypothesis of a southward shift in the Intertropical Convergence Zone (ITCZ) at this time and increased precipitation over Kiritimati. The LIA does not appear anomalously wet in Kiritimati relative to the 20th century, and higher frequency variability in the Kiritimati sediment laminae indicates microbial mats continued to grow at multidecadal intervals until 1700 AD. The periodicity of sub-mm scale laminations within the buried microbial mats is highly variable, and indicates mat-carbonate laminae are too frequent to be related to seasonal or ENSO periodicity. Such laminae are likely related to the organization of microbial communities and organomineralization along environmental microgradients in microbial mats.
-
Four Tropical Cyclones Across the Entire Pacific Ocean
2017-12-08
This GOES-West satellite image shows four tropical cyclones in the North Western, Central and Eastern Pacific Ocean on September 1, 2015. In the Western Pacific (far left) is Typhoon Kilo. Moving east (to the right) into the Central Pacific is Hurricane Ignacio (just east of Hawaii), and Hurricane Jimena. The eastern-most storm is Tropical Depression 14E in the Eastern Pacific. Credit: NASA/NOAA GOES Project NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
-
Air-sea interaction in the tropical Pacific Ocean
NASA Technical Reports Server (NTRS)
Allison, L. J.; Steranka, J.; Holub, R. J.; Hansen, J.; Godshall, F. A.; Prabhakara, C.
1972-01-01
Charts of 3-month sea surface temperature (SST) anomalies in the eastern tropical Pacific Ocean were produced for the period 1949 to 1970. The anomalies along the United States and South American west coasts and in the eastern tropical Pacific appeared to be oscillating in phase during this period. Similarly, the satellite-derived cloudiness for each of four quadrants of the Pacific Ocean (130 deg E to 100 deg W, 30 deg N to 25 deg S) appeared to be oscillating in phase. In addition, a global tropical cloudiness oscillation from 30 deg N to 30 deg S was noted from 1965 to 1970, by using monthly satellite television nephanalyses. The SST anomalies were found to have a good degree of correlation both positive and negative with the following monthly geophysical parameters: (1) satellite-derived cloudiness, (2) strength of the North and South Pacific semipermanent anticyclones, (3) tropical Pacific island rainfall, and (4) Darwin surface pressure. Several strong direct local and crossequatorial relationships were noted. In particular, the high degree of correlation between the tropical island rainfall and the SST anomalies (r = +0.93) permitted the derivation of SST's for the tropical Pacific back to 1905. The close occurrence of cold tropical SST and North Pacific 700-mb positive height anomalies with central United States drought conditions was noted.
-
NASA Astrophysics Data System (ADS)
Rustic, G. T.; Polissar, P. J.; Ravelo, A. C.; White, S. M.
2017-12-01
The El Niño Southern Oscillation (ENSO) plays a dominant role in Earth's climate variability. Paleoceanographic evidence suggests that ENSO has changed in the past, and these changes have been linked to large-scale climatic shifts. While a close relationship between ENSO evolution and climate boundary conditions has been predicted, testing these predictions remains challenging. These climate boundary conditions, including insolation, the mean surface temperature gradient of the tropical Pacific, global ice volume, and tropical thermocline depth, often co-vary and may work together to suppress or enhance the ocean-atmosphere feedbacks that drive ENSO variability. Furthermore, suitable paleo-archives spanning multiple climate states are sparse. We have aimed to test ENSO response to changing climate boundary conditions by generating new reconstructions of mixed-layer variability from sedimentary archives spanning the last three glacial-interglacial cycles from the Central Tropical Pacific Line Islands, where El Niño is strongly expressed. We analyzed Mg/Ca ratios from individual foraminifera to reconstruct mixed-layer variability at discrete time intervals representing combinations of climatic boundary conditions from the middle Holocene to Marine Isotope Stage (MIS) 8. We observe changes in the mixed-layer temperature variability during MIS 5 and during the previous interglacial (MIS 7) showing significant reductions in ENSO amplitude. Differences in variability during glacial and interglacial intervals are also observed. Additionally, we reconstructed mixed-layer and thermocline conditions using multi-species Mg/Ca and stable isotope measurements to more fully characterize the state of the Central Tropical Pacific during these intervals. These reconstructions provide us with a unique view of Central Tropical Pacific variability and water-column structure at discrete intervals under varying boundary climate conditions with which to assess factors that shape ENSO
-
Interannual Weakening of the Tropical Pacific Walker Circulation Due to Strong Tropical Volcanism
NASA Astrophysics Data System (ADS)
Miao, Jiapeng; Wang, Tao; Wang, Huijun; Sun, Jianqi
2018-06-01
In order to examine the response of the tropical Pacific Walker circulation (PWC) to strong tropical volcanic eruptions (SVEs), we analyzed a three-member long-term simulation performed with HadCM3, and carried out four additional CAM4 experiments. We found that the PWC shows a significant interannual weakening after SVEs. The cooling effect from SVEs is able to cool the entire tropics. However, cooling over the Maritime Continent is stronger than that over the central-eastern tropical Pacific. Thus, non-uniform zonal temperature anomalies can be seen following SVEs. As a result, the sea level pressure gradient between the tropical Pacific and the Maritime Continent is reduced, which weakens trade winds over the tropical Pacific. Therefore, the PWC is weakened during this period. At the same time, due to the cooling subtropical and midlatitude Pacific, the Intertropical Convergence Zone (ITCZ) and South Pacific convergence zone (SPCZ) are weakened and shift to the equator. These changes also contribute to the weakened PWC. Meanwhile, through the positive Bjerknes feedback, weakened trade winds cause El Niño-like SST anomalies over the tropical Pacific, which in turn further influence the PWC. Therefore, the PWC significantly weakens after SVEs. The CAM4 experiments further confirm the influences from surface cooling over the Maritime Continent and subtropical/midlatitude Pacific on the PWC. Moreover, they indicate that the stronger cooling over the Maritime Continent plays a dominant role in weakening the PWC after SVEs. In the observations, a weakened PWC and a related El Niño-like SST pattern can be found following SVEs.
-
An aftereffect of global warming on tropical Pacific decadal variability
NASA Astrophysics Data System (ADS)
Zheng, Jian; Liu, Qinyu; Wang, Chuanyang
2018-03-01
Studies have shown that global warming over the past six decades can weaken the tropical Pacific Walker circulation and maintain the positive phase of the Interdecadal Pacific Oscillation (IPO). Based on observations and model simulations, another aftereffect of global warming on IPO is found. After removing linear trends (global warming signals) from observations, however, the tropical Pacific climate still exhibited some obvious differences between two IPO negative phases. The boreal winter (DJF) equatorial central-eastern Pacific sea surface temperature (SST) was colder during the 1999-2014 period (P2) than that during 1961-1976 (P1). This difference may have been a result of global warming nonlinear modulation of precipitation; i.e., in the climatological rainy region, the core area of the tropical Indo-western Pacific warm pool receives more precipitation through the "wet-get-wetter" mechanism. Positive precipitation anomalies in the warm pool during P2 are much stronger than those during P1, even after subtracting the linear trend. Corresponding to the differences of precipitation, the Pacific Walker circulation is stronger in P2 than in P1. Consequent easterly winds over the equatorial Pacific led to a colder equatorial eastern-central Pacific during P2. Therefore, tropical Pacific climate differences between the two negative IPO phases are aftereffects of global warming. These aftereffects are supported by the results of coupled climate model experiments, with and without global warming.
-
NASA Astrophysics Data System (ADS)
Wu, Renguang; Cao, Xi
2017-06-01
The present study contrasts interannual variations in the intensity of boreal summer 10-20-day and 30-60-day intraseasonal oscillations (ISOs) over the tropical western North Pacific and their factors. A pronounced difference is found in the relationship of the two ISOs to El Niño-Southern Oscillation. The 10-20-day ISO intensity is enhanced during El Niño developing summer, whereas the 30-60-day ISO intensity is enhanced during La Niña decaying summer. The above different relationship is interpreted as follows. The equatorial central and eastern Pacific SST anomalies modify vertical wind shear, lower-level moisture, and vertical motion in a southeast-northwest oriented band from the equatorial western Pacific to the tropical western North Pacific where the 10-20-day ISOs originate and propagate. These background field changes modulate the amplitude of 10-20-day ISOs. Preceding equatorial central and eastern Pacific SST anomalies induce SST anomalies in the North Indian Ocean in summer, which in turn modify vertical wind shear and vertical motion over the tropical western North Pacific. The modified background fields influence the amplitude of the 30-60-day ISOs when they reach the tropical western North Pacific from the equatorial region. A feedback of ISO intensity on local SST change is identified in the tropical western North Pacific likely due to a net effect of ISOs on surface heat flux anomalies. This feedback is more prominent from the 10-20-day than the 30-60-day ISO intensity change.
-
NASA Astrophysics Data System (ADS)
Han, Weiqing; Meehl, Gerald A.; Hu, Aixue; Alexander, Michael A.; Yamagata, Toshio; Yuan, Dongliang; Ishii, Masayoshi; Pegion, Philip; Zheng, Jian; Hamlington, Benjamin D.; Quan, Xiao-Wei; Leben, Robert R.
2014-09-01
Previous studies have linked the rapid sea level rise (SLR) in the western tropical Pacific (WTP) since the early 1990s to the Pacific decadal climate modes, notably the Pacific Decadal Oscillation in the north Pacific or Interdecadal Pacific Oscillation (IPO) considering its basin wide signature. Here, the authors investigate the changing patterns of decadal (10-20 years) and multidecadal (>20 years) sea level variability (global mean SLR removed) in the Pacific associated with the IPO, by analyzing satellite and in situ observations, together with reconstructed and reanalysis products, and performing ocean and atmosphere model experiments. Robust intensification is detected for both decadal and multidecadal sea level variability in the WTP since the early 1990s. The IPO intensity, however, did not increase and thus cannot explain the faster SLR. The observed, accelerated WTP SLR results from the combined effects of Indian Ocean and WTP warming and central-eastern tropical Pacific cooling associated with the IPO cold transition. The warm Indian Ocean acts in concert with the warm WTP and cold central-eastern tropical Pacific to drive intensified easterlies and negative Ekman pumping velocity in western-central tropical Pacific, thereby enhancing the western tropical Pacific SLR. On decadal timescales, the intensified sea level variability since the late 1980s or early 1990s results from the "out of phase" relationship of sea surface temperature anomalies between the Indian and central-eastern tropical Pacific since 1985, which produces "in phase" effects on the WTP sea level variability.
-
Coolness in the tropical Pacific during an El Nino episode
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chou, M.
The response of radiation budgets to changes in water vapor and clouds in an El Nino episode is investigated using the analyzed sea surface temperature (SST) and satellite-derived clouds and the earth radiation budgets for the tropical Pacific (30 deg N-30 deg S, 100 deg E-100 deg W). Analyses are performed for April 1985 and April 1987. The former is a non-El Nino year and the latter is an El Nino year. Compared to April 1985, when the SST over the central and eastern equatorial Pacific is approximately 2 C lower, the high-level cloudiness in April 1987 increases in themore » central and eastern equatorial Pacific. Corresponding to the increase in cloudiness, the outgoing longwave radiation and the net downward solar radiation at the top of the atmosphere decrease. The patterns of these changes are reversed in the western tropical Pacific and the Northern Hemispheric (NH) subsidence region centered at approximately 20 deg N, indicating an eastward shift of the convection center from the maritime continents to the central equatorial Pacific and a strengthened NH Hadley circulation. The earth-atmosphere system in the region receives less radiative energy by 4 W/sq m in the warmer month of April 1987 than in the month of April 1985, which is primarily caused by a reduced atmospheric clear sky greenhouse effect in the NH tropical Pacific in April 1987. Clouds have strong effects on both the IR and solar radiation, but the net effect on the radiation budget at the top of the atmopshere changes only slightly between April 1985 and April 1987. The results are consistent with Lindzen`s hypothesis that reduced upper-tropospheric water vapor in the vicinity of the enhanced convection region produces cooling that counteracts warming in the Tropics.« less
-
Pacific Exploratory Mission in the tropical Pacific: PEM-Tropics A, August-September 1996
NASA Astrophysics Data System (ADS)
Hoell, J. M.; Davis, D. D.; Jacob, D. J.; Rodgers, M. O.; Newell, R. E.; Fuelberg, H. E.; McNeal, R. J.; Raper, J. L.; Bendura, R. J.
1999-03-01
The NASA Pacific Exploratory Mission to the Pacific tropics (PEM-Tropics) is the third major field campaign of NASA's Global Tropospheric Experiment (GTE) to study the impact of human and natural processes on the chemistry of the troposphere over the Pacific basin. The first two campaigns, PEM-West A and B were conducted over the northwestern regions of the Pacific and focused on the impact of emissions from the Asian continent. The broad objectives of PEM-Tropics included improving our understanding of the oxidizing power of the tropical atmosphere as well as investigating oceanic sulfur compounds and their conversion to aerosols. Phase A of the PEM-Tropics program, conducted between August-September 1996, involved the NASA DC-8 and P-3B aircraft. Phase B of this program is scheduled for March/April 1999. During PEM-Tropics A, the flight tracks of the two aircraft extended zonally across the entire Pacific Basin and meridionally from Hawaii to south of New Zealand. Both aircraft were instrumented for airborne measurements of trace gases and aerosols and meteorological parameters. The DC-8, given its long-range and high-altitude capabilities coupled with the lidar instrument in its payload, focused on transport issues and ozone photochemistry, while the P-3B, with its sulfur-oriented instrument payload and more limited range, focused on detailed sulfur process studies. Among its accomplishments, the PEM-Tropics A field campaign has provided a unique set of atmospheric measurements in a heretofore data sparse region; demonstrated the capability of several new or improved instruments for measuring OH, H2SO4, NO, NO2, and actinic fluxes; and conducted experiments which tested our understanding of HOx and NOx photochemistry, as well as sulfur oxidation and aerosol formation processes. In addition, PEM-Tropics A documented for the first time the considerable and widespread influence of biomass burning pollution over the South Pacific, and identified the South Pacific
-
NASA Technical Reports Server (NTRS)
Rodgers, Edward B.; Adler, Robert F.; Pierce, Harold F.
1997-01-01
Tropical cyclone monthly rainfall amounts are estimated from passive microwave satellite observations for an eleven year period. These satellite-derived rainfall amounts are used to assess the impact of tropical cyclone rainfall in altering the geographical, seasonal, and inter-annual distribution of the North Pacific Ocean total rainfall during June-November when tropical cyclones are most important. To estimate these tropical cyclone rainfall amounts, mean monthly rain rates are derived from passive microwave satellite observations within 444 km radius of the center of those North Pacific tropical cyclones that reached storm stage and greater. These rain rate observations are converted to monthly rainfall amounts and then compared to those for non-tropical cyclone systems. The main results of this study indicate that: 1) tropical cyclones contribute 7% of the rainfall to the entire domain of the North Pacific during the tropical cyclone season and 12%, 3%, and 4% when the study area is limited to, respectively, the western, central, and eastern third of the ocean; 2) the maxima in tropical cyclone rainfall are poleward (5 deg to 10 deg latitude depending on longitude) of the maxima in non-tropical cyclone rainfall; 3) tropical cyclones contribute a maximum of 30% northeast of the Philippine Islands and 40% of the lower Baja California coast; 4) in the western North Pacific, the tropical cyclone rainfall lags the total rainfall by approximately two months and shows seasonal latitudinal variation following the ITCZ; and 5) in general, tropical cyclone rainfall is enhanced during the El Nino years by warm SSTs in the eastern North Pacific and by the monsoon trough in the western and central North Pacific.
-
NASA Astrophysics Data System (ADS)
Rodgers, Edward B.; Adler, Robert F.; Pierce, Harold F.
2000-10-01
Tropical cyclone monthly rainfall amounts are estimated from passive microwave satellite observations for an 11-yr period. These satellite-derived rainfall amounts are used to assess the impact of tropical cyclone rainfall in altering the geographical, seasonal, and interannual distribution of the North Pacific Ocean total rainfall during June-November when tropical cyclones are most important.To estimate these tropical cyclone rainfall amounts, mean monthly rain rates are derived from passive microwave satellite observations within 444-km radius of the center of those North Pacific tropical cyclones that reached storm stage and greater. These rain-rate observations are converted to monthly rainfall amounts and then compared with those for nontropical cyclone systems.The main results of this study indicate that 1) tropical cyclones contribute 7% of the rainfall to the entire domain of the North Pacific during the tropical cyclone season and 12%, 3%, and 4% when the study area is limited to, respectively, the western, central, and eastern third of the ocean; 2) the maximum tropical cyclone rainfall is poleward (5°-10° latitude depending on longitude) of the maximum nontropical cyclone rainfall; 3) tropical cyclones contribute a maximum of 30% northeast of the Philippine Islands and 40% off the lower Baja California coast; 4) in the western North Pacific, the tropical cyclone rainfall lags the total rainfall by approximately two months and shows seasonal latitudinal variation following the Intertropical Convergence Zone; and 5) in general, tropical cyclone rainfall is enhanced during the El Niño years by warm SSTs in the eastern North Pacific and by the monsoon trough in the western and central North Pacific.
-
NASA Astrophysics Data System (ADS)
Park, In-Hong; Min, Seung-Ki; Yeh, Sang-Wook; Weller, Evan; Kim, Seon Tae
2017-04-01
This study assessed the anthropogenic contribution to the 2015 record-breaking high sea surface temperatures (SSTs) observed in the central equatorial Pacific and tropical Indian Ocean. Considering a close link between extreme warm events in these regions, we conducted a joint attribution analysis using a fraction of attributable risk approach. Probability of occurrence of such extreme anomalies and long-term trends for the two oceanic regions were compared between CMIP5 multi-model simulations with and without anthropogenic forcing. Results show that the excessive warming in both regions is well beyond the range of natural variability and robustly attributable to human activities due to greenhouse gas increase. We further explored associated mechanisms including the Bjerknes feedback and background anthropogenic warming. It is concluded that background warming was the main contribution to the 2015 extreme SST event over the central equatorial Pacific Ocean on a developing El Niño condition, which in turn induced the extreme SST event over the tropical Indian Ocean through the atmospheric bridge effect.
-
Decadal trends of the upper ocean salinity in the tropical Indo-Pacific since mid-1990s
NASA Astrophysics Data System (ADS)
DU, Y.; Zhang, Y.
2016-02-01
A contrasting trend pattern of sea surface salinity (SSS) between the western tropical Pacific (WTP) and the southeastern tropical Indian Ocean (SETIO) is observed during 2004-2013, with significant salinity increase in the WTP and freshening in the SETIO. In this study, we show that increased precipitation around the Maritime Continent (MC), decreased precipitation in the western-central tropical Pacific, and ocean advection processes contribute to the salinity trends in the region. From a longer historical record, these salinity trends started in the mid-1990s, a few years before the Global Warming Hiatus from 1998 to present. The salinity trends are associated a strengthening trend of the Walker Circulation over the tropical Indo-Pacific, which have reversed the long-term salinity changes in the tropical Indo-Pacific as a consequence of global warming. Understanding decadal variations of SSS in the tropical Indo-Pacific will better inform on how the tropical hydrological cycle will be affected by the natural variability and a warming climate.
-
Decadal trends of the upper ocean salinity in the tropical Indo-Pacific since mid-1990s
NASA Astrophysics Data System (ADS)
Du, Yan; Zhang, Yuhong; Feng, Ming; Wang, Tianyu; Zhang, Ningning; Wijffels, Susan
2015-11-01
A contrasting trend pattern of sea surface salinity (SSS) between the western tropical Pacific (WTP) and the southeastern tropical Indian Ocean (SETIO) is observed during 2004-2013, with significant salinity increase in the WTP and freshening in the SETIO. In this study, we show that increased precipitation around the Maritime Continent (MC), decreased precipitation in the western-central tropical Pacific, and ocean advection processes contribute to the salinity trends in the region. From a longer historical record, these salinity trends started in the mid-1990s, a few years before the Global Warming Hiatus from 1998 to present. The salinity trends are associated a strengthening trend of the Walker Circulation over the tropical Indo-Pacific, which have reversed the long-term salinity changes in the tropical Indo-Pacific as a consequence of global warming. Understanding decadal variations of SSS in the tropical Indo-Pacific will better inform on how the tropical hydrological cycle will be affected by the natural variability and a warming climate.
-
Decadal trends of the upper ocean salinity in the tropical Indo-Pacific since mid-1990s
Du, Yan; Zhang, Yuhong; Feng, Ming; Wang, Tianyu; Zhang, Ningning; Wijffels, Susan
2015-01-01
A contrasting trend pattern of sea surface salinity (SSS) between the western tropical Pacific (WTP) and the southeastern tropical Indian Ocean (SETIO) is observed during 2004–2013, with significant salinity increase in the WTP and freshening in the SETIO. In this study, we show that increased precipitation around the Maritime Continent (MC), decreased precipitation in the western-central tropical Pacific, and ocean advection processes contribute to the salinity trends in the region. From a longer historical record, these salinity trends started in the mid-1990s, a few years before the Global Warming Hiatus from 1998 to present. The salinity trends are associated a strengthening trend of the Walker Circulation over the tropical Indo-Pacific, which have reversed the long-term salinity changes in the tropical Indo-Pacific as a consequence of global warming. Understanding decadal variations of SSS in the tropical Indo-Pacific will better inform on how the tropical hydrological cycle will be affected by the natural variability and a warming climate. PMID:26522168
-
Decadal trends of the upper ocean salinity in the tropical Indo-Pacific since mid-1990s.
Du, Yan; Zhang, Yuhong; Feng, Ming; Wang, Tianyu; Zhang, Ningning; Wijffels, Susan
2015-11-02
A contrasting trend pattern of sea surface salinity (SSS) between the western tropical Pacific (WTP) and the southeastern tropical Indian Ocean (SETIO) is observed during 2004-2013, with significant salinity increase in the WTP and freshening in the SETIO. In this study, we show that increased precipitation around the Maritime Continent (MC), decreased precipitation in the western-central tropical Pacific, and ocean advection processes contribute to the salinity trends in the region. From a longer historical record, these salinity trends started in the mid-1990s, a few years before the Global Warming Hiatus from 1998 to present. The salinity trends are associated a strengthening trend of the Walker Circulation over the tropical Indo-Pacific, which have reversed the long-term salinity changes in the tropical Indo-Pacific as a consequence of global warming. Understanding decadal variations of SSS in the tropical Indo-Pacific will better inform on how the tropical hydrological cycle will be affected by the natural variability and a warming climate.
-
Zhang, Zhiyuan; Ren, Baohua; Zheng, Jianqiu
2017-02-17
Using empirical orthogonal function (EOF) analysis of the monthly tropical Pacific subsurface ocean temperature anomalies (SOTA) from 1979 to 2014, we detected three leading modes in the tropical Pacific subsurface temperature. The first mode has a dipole pattern, with warming in the eastern Pacific and cooling in the western Pacific, and is closely related to traditional El Niño. The second mode has a monopole pattern, with only warming in the central Pacific subsurface. The third mode has a zonal tripole pattern, with warming in the off-equatorial central Pacific and cooling in the far eastern Pacific and western Pacific. The second and third modes are both related to El Niño Modoki. Mode 1 is linked with a Kelvin wave that propagates from the central to the eastern Pacific and is induced by the anomalous westerlies that propagate from the western to the central Pacific. Mode 2 is also linked with a Kelvin wave that propagates from the western to the central Pacific induced by the enhancement of westerlies over the western Pacific. Mode 3 is linked with a Rossby wave that propagates from the central to the western Pacific driven by the anomalous easterlies over the eastern Pacific.
-
Wang, Wuke; Matthes, Katja; Omrani, Nour-Eddine; Latif, Mojib
2016-07-12
Tropopause temperatures (TPTs) control the amount of stratospheric water vapour, which influences chemistry, radiation and circulation in the stratosphere, and is also an important driver of surface climate. Decadal variability and long-term trends in tropical TPTs as well as stratospheric water vapour are largely unknown. Here, we present for the first time evidence, from reanalysis and state-of-the-art climate model simulations, of a link between decadal variability in tropical TPTs and the Pacific Decadal Oscillation (PDO). The negative phase of the PDO is associated with anomalously cold sea surface temperatures (SSTs) in the tropical east and central Pacific, which enhance the zonal SST gradient across the equatorial Pacific. The latter drives a stronger Walker Circulation and a weaker Hadley Circulation, which leads to less convection and subsequently a warmer tropopause over the central equatorial Pacific. Over the North Pacific, positive sea level pressure anomalies occur, which damp vertical wave propagation into the stratosphere. This in turn slows the Brewer-Dobson circulation, and hence warms the tropical tropopause, enabling more water vapour to enter the stratosphere. The reverse chain of events holds for the positive phase of the PDO. Such ocean-troposphere-stratosphere interactions may provide an important feedback on the Earth's global surface temperature.
-
Wang, Wuke; Matthes, Katja; Omrani, Nour-Eddine; Latif, Mojib
2016-01-01
Tropopause temperatures (TPTs) control the amount of stratospheric water vapour, which influences chemistry, radiation and circulation in the stratosphere, and is also an important driver of surface climate. Decadal variability and long-term trends in tropical TPTs as well as stratospheric water vapour are largely unknown. Here, we present for the first time evidence, from reanalysis and state-of-the-art climate model simulations, of a link between decadal variability in tropical TPTs and the Pacific Decadal Oscillation (PDO). The negative phase of the PDO is associated with anomalously cold sea surface temperatures (SSTs) in the tropical east and central Pacific, which enhance the zonal SST gradient across the equatorial Pacific. The latter drives a stronger Walker Circulation and a weaker Hadley Circulation, which leads to less convection and subsequently a warmer tropopause over the central equatorial Pacific. Over the North Pacific, positive sea level pressure anomalies occur, which damp vertical wave propagation into the stratosphere. This in turn slows the Brewer-Dobson circulation, and hence warms the tropical tropopause, enabling more water vapour to enter the stratosphere. The reverse chain of events holds for the positive phase of the PDO. Such ocean-troposphere-stratosphere interactions may provide an important feedback on the Earth’s global surface temperature. PMID:27404090
-
NASA Technical Reports Server (NTRS)
Rodgers, Edward; Pierce, Harold; Adler, Robert
1999-01-01
Tropical cyclone monthly rainfall amounts are estimated from passive microwave satellite observations in the North Atlantic and in three equal geographical regions of the North Pacific (i.e., Western, Central, and Eastern North Pacific). These satellite-derived rainfall amounts are used to assess the impact of tropical cyclone rainfall in altering the geographical, seasonal, and inter-annual distribution of the 1987-1989, 1991-1998 North Atlantic and Pacific rainfall during June-November when tropical cyclones are most abundant. To estimate these tropical cyclone rainfall amounts, mean monthly rain rates are derived from the Defence Meteorological Satellite Program (DMSP) Special Sensor Microwave/ Radiometer (SSM/I) observations within 444 km radius of the center of those North Atlantic and Pacific tropical cyclones that reached storm stage and greater. These rain rate observations are then multiplied by the number of hours in a given month. Mean monthly rainfall amounts are also constructed for all the other North Atlantic and Pacific raining systems during this eleven year period for the purpose of estimating the geographical distribution and intensity of rainfall contributed by non-tropical cyclone systems. Further, the combination of the non-tropical cyclone and tropical cyclone (i.e., total) rainfall is constructed to delineate the fractional amount that tropical cyclones contributed to the total North Pacific rainfall.
-
Long-term Internal Variability of the Tropical Pacific Atmosphere-Ocean System
NASA Astrophysics Data System (ADS)
Hadi Bordbar, Mohammad; Martin, Thomas; Park, Wonsun; Latif, Mojib
2016-04-01
The tropical Pacific has featured some remarkable trends during the recent decades such as an unprecedented strengthening of the Trade Winds, a strong cooling of sea surface temperatures (SST) in the eastern and central part, thereby slowing global warming and strengthening the zonal SST gradient, and highly asymmetric sea level trends with an accelerated rise relative to the global average in the western and a drop in the eastern part. These trends have been linked to an anomalously strong Pacific Walker Circulation, the major zonal atmospheric overturning cell in the tropical Pacific sector, but the origin of the strengthening is controversial. Here we address the question as to whether the recent decadal trends in the tropical Pacific atmosphere-ocean system are within the range of internal variability, as simulated in long unforced integrations of global climate models. We show that the recent trends are still within the range of long-term internal decadal variability. Further, such variability strengthens in response to enhanced greenhouse gas concentrations, which may further hinder detection of anthropogenic climate signals in that region.
-
Global Warming Attenuates the Tropical Atlantic-Pacific Teleconnection
Jia, Fan; Wu, Lixin; Gan, Bolan; Cai, Wenju
2016-01-01
Changes in global sea surface temperature (SST) since the end of last century display a pattern of widespread warming intercepted by cooling in the eastern equatorial Pacific and western coasts of the American continent. Studies have suggested that the cooling in the eastern equatorial Pacific may be partly induced by warming in the North Atlantic. However, it remains unknown how stable this inter-tropical teleconnection will be under global warming. Here we show that the inter-tropical teleconnection from the tropical Atlantic to Pacific weakens substantially as the CO2 concentration increases. This reduced impact is related to the El Niño-like warming of the tropical Pacific mean state, which leads to limited seasonal migration of the Pacific inter-tropical convergence zone (ITCZ) and weakened ocean heat transport. A fast decay of the tropical Atlantic SST anomalies in a warmer climate also contributes to the weakened teleconnection. Our study suggests that as greenhouse warming continues, the trend in the tropical Pacific as well as the development of ENSO will be less frequently interrupted by the Atlantic because of this attenuation. The weakened teleconnection is also supported by CMIP5 models, although only a few of these models can capture this inter-tropical teleconnection. PMID:26838053
-
Global Warming Attenuates the Tropical Atlantic-Pacific Teleconnection.
Jia, Fan; Wu, Lixin; Gan, Bolan; Cai, Wenju
2016-02-03
Changes in global sea surface temperature (SST) since the end of last century display a pattern of widespread warming intercepted by cooling in the eastern equatorial Pacific and western coasts of the American continent. Studies have suggested that the cooling in the eastern equatorial Pacific may be partly induced by warming in the North Atlantic. However, it remains unknown how stable this inter-tropical teleconnection will be under global warming. Here we show that the inter-tropical teleconnection from the tropical Atlantic to Pacific weakens substantially as the CO2 concentration increases. This reduced impact is related to the El Niño-like warming of the tropical Pacific mean state, which leads to limited seasonal migration of the Pacific inter-tropical convergence zone (ITCZ) and weakened ocean heat transport. A fast decay of the tropical Atlantic SST anomalies in a warmer climate also contributes to the weakened teleconnection. Our study suggests that as greenhouse warming continues, the trend in the tropical Pacific as well as the development of ENSO will be less frequently interrupted by the Atlantic because of this attenuation. The weakened teleconnection is also supported by CMIP5 models, although only a few of these models can capture this inter-tropical teleconnection.
-
Role of internal variability in recent decadal to multidecadal tropical Pacific climate changes
NASA Astrophysics Data System (ADS)
Bordbar, Mohammad Hadi; Martin, Thomas; Latif, Mojib; Park, Wonsun
2017-05-01
While the Earth's surface has considerably warmed over the past two decades, the tropical Pacific has featured a cooling of sea surface temperatures in its eastern and central parts, which went along with an unprecedented strengthening of the equatorial trade winds, the surface component of the Pacific Walker Circulation (PWC). Previous studies show that this decadal trend in the trade winds is generally beyond the range of decadal trends simulated by climate models when forced by historical radiative forcing. There is still a debate on the origin of and the potential role that internal variability may have played in the recent decadal surface wind trend. Using a number of long control (unforced) integrations of global climate models and several observational data sets, we address the question as to whether the recent decadal to multidecadal trends are robustly classified as an unusual event or the persistent response to external forcing. The observed trends in the tropical Pacific surface climate are still within the range of the long-term internal variability spanned by the models but represent an extreme realization of this variability. Thus, the recent observed decadal trends in the tropical Pacific, though highly unusual, could be of natural origin. We note that the long-term trends in the selected PWC indices exhibit a large observational uncertainty, even hindering definitive statements about the sign of the trends.
Plain Language SummaryWhile the Earth's surface has considerably warmed over the past two decades, the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> has featured a cooling of sea surface temperatures in its eastern and <span class="hlt">central</span> parts, which went along with an unprecedented strengthening of the equatorial trade winds. Here we show that climate models simulate a high level of internal variability, so that the recent changes in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> could still be due to natural processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ClDy...50.4335P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ClDy...50.4335P"><span>Covariability of <span class="hlt">Central</span> America/Mexico winter precipitation and <span class="hlt">tropical</span> sea surface temperatures</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pan, Yutong; Zeng, Ning; Mariotti, Annarita; Wang, Hui; Kumar, Arun; Sánchez, René Lobato; Jha, Bhaskar</p> <p>2018-06-01</p> <p>In this study, the relationships between <span class="hlt">Central</span> America/Mexico (CAM) winter precipitation and <span class="hlt">tropical</span> <span class="hlt">Pacific</span>/Atlantic sea surface temperatures (SSTs) are examined based on 68-year (1948-2015) observations and 59-year (1957-2015) atmospheric model simulations forced by observed SSTs. The covariability of the winter precipitation and SSTs is quantified using the singular value decomposition (SVD) method with observational data. The first SVD mode relates out-of-phase precipitation anomalies in northern Mexico and <span class="hlt">Central</span> America to the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> El Niño/La Niña SST variation. The second mode links a decreasing trend in the precipitation over <span class="hlt">Central</span> America to the warming of SSTs in the <span class="hlt">tropical</span> Atlantic, as well as in the <span class="hlt">tropical</span> western <span class="hlt">Pacific</span> and the <span class="hlt">tropical</span> Indian Ocean. The first mode represents 67% of the covariance between the two fields, indicating a strong association between CAM winter precipitation and El Niño/La Niña, whereas the second mode represents 20% of the covariance. The two modes account for 32% of CAM winter precipitation variance, of which, 17% is related to the El Niño/La Niña SST and 15% is related to the SST warming trend. The atmospheric circulation patterns, including 500-hPa height and low-level winds obtained by linear regressions against the SVD SST time series, are dynamically consistent with the precipitation anomaly patterns. The model simulations driven by the observed SSTs suggest that these precipitation anomalies are likely a response to <span class="hlt">tropical</span> SST forcing. It is also shown that there is significant potential predictability of CAM winter precipitation given <span class="hlt">tropical</span> SST information.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ClDy...50.1439H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ClDy...50.1439H"><span>Interdecadal variation of <span class="hlt">tropical</span> cyclone genesis and its relationship to the convective activities over the <span class="hlt">central</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Huangfu, Jingliang; Huang, Ronghui; Chen, Wen</p> <p>2018-02-01</p> <p>Using the outgoing longwave radiation (OLR) data from the National Oceanic and Atmospheric Administration archives, this paper analyzes the interdecadal variation of convective activities over the <span class="hlt">central</span> <span class="hlt">Pacific</span> (CP) from July to October of 1979-2013 and its impact on <span class="hlt">tropical</span> cyclone (TC) genesis in the western North <span class="hlt">Pacific</span> (WNP). Concurrent with the interdecadal decrease of TC genesis, the <span class="hlt">tropical</span> convection underwent a significant interdecadal change in the late 1990s. Overall, the first leading empirical orthogonal function mode of the <span class="hlt">tropical</span> OLR during July-October turned from a zonal dipole pattern during 1979-1997 to a tripole pattern during 1998-2013. Concomitant to this change, the boreal part of the Walker circulation shrank westward, with its downdraft branch located over the CP. The downward motion anomalies over the CP increased after the late 1990s, as did the trade easterlies. Consistent with the CP convective activity anomalies, the negative low-level relative vorticity anomalies and upper-level divergence anomalies, positive vertical wind shear anomalies and anomalous abundant water vapor can be observed over the southeastern part of the WNP. Additionally, the <span class="hlt">tropical</span> depression (TD)-type waves associated with the CP convective activities are significantly different before and after the late 1990s. Before the late 1990s, the off-equatorial TD-type waves could be distinctly observed, with clear transitions located along the WNP monsoon trough. However, these transitions were vague after the late 1990s. Therefore, the convective activities over the CP may have played an important role in affecting the interdecadal change of TC genesis by affecting the genesis of TD-type waves.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUSM.A31A..08D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUSM.A31A..08D"><span>Warm Water Pools of the Western Caribbean and Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span>: Their Influence on Intraseasonal Rainfall Regimes and <span class="hlt">Tropical</span> Storm Activity in Mexico</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Douglas, A. V.; Englehart, P. J.</p> <p>2007-05-01</p> <p>A dipole in <span class="hlt">tropical</span> cyclone development between the Caribbean and the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> will be examined relative to its affect on southern Mexican rainfall. With the change over in the AMO and PDO in 1994 and 1998, respectively, <span class="hlt">tropical</span> storm genesis has been increasing in the Caribbean while declining in the <span class="hlt">tropical</span> east <span class="hlt">Pacific</span>. This dipole in <span class="hlt">tropical</span> cyclone development appears to be related to changes in the pre storm season heat content of the two ocean basins (data Scripps Institution of Oceanography). Preliminary work indicates that if the Caribbean is warmer than the <span class="hlt">Pacific</span> by late May the dipole will be accentuated with a pronounced decrease in <span class="hlt">tropical</span> storms in the east <span class="hlt">Pacific</span> with an early and prolonged season in the Caribbean. In recent years there appears to have been an increase in the intensity and duration of midsummer drought (Canicula) in Mexico associated with changes in the PDO and AMO. These long term ocean oscillations appear to control the dipole in the strength of the Caribbean and East <span class="hlt">Pacific</span> warm pools. Mid summer drought is a normal occurrence in much of Mexico and <span class="hlt">Central</span> America, but the intensified droughts of the recent period have stressed the agricultural community of the region. Based on preliminary work, it appears that the recent increased frequency of midsummer drought can be linked to a shift in the warmest pool from the East <span class="hlt">Pacific</span> to the Caribbean.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26213676','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26213676"><span>Salinity fronts in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kao, Hsun-Ying; Lagerloef, Gary S E</p> <p>2015-02-01</p> <p>This study delineates the salinity fronts (SF) across the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, and describes their variability and regional dynamical significance using Aquarius satellite observations. From the monthly maps of the SF, we find that the SF in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> are (1) usually observed around the boundaries of the fresh pool under the intertropical convergence zone (ITCZ), (2) stronger in boreal autumn than in other seasons, and (3) usually stronger in the eastern <span class="hlt">Pacific</span> than in the western <span class="hlt">Pacific</span>. The relationship between the SF and the precipitation and the surface velocity are also discussed. We further present detailed analysis of the SF in three key <span class="hlt">tropical</span> <span class="hlt">Pacific</span> regions. Extending zonally around the ITCZ, where the temperature is nearly homogeneous, we find the strong SF of 1.2 psu from 7° to 11°N to be the main contributor of the horizontal density difference of 0.8 kg/m 3 . In the eastern <span class="hlt">Pacific</span>, we observe a southward extension of the SF in the boreal spring that could be driven by both precipitation and horizontal advection. In the western <span class="hlt">Pacific</span>, the importance of these newly resolved SF associated with the western <span class="hlt">Pacific</span> warm/fresh pool and El Niño southern oscillations are also discussed in the context of prior literature. The main conclusions of this study are that (a) Aquarius satellite salinity measurements reveal the heretofore unknown proliferation, structure, and variability of surface salinity fronts, and that (b) the fine-scale structures of the SF in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> yield important new information on the regional air-sea interaction and the upper ocean dynamics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EOSTr..95..196L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EOSTr..95..196L"><span><span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Observing for the Next Decade</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Legler, David M.; Hill, Katherine</p> <p>2014-06-01</p> <p>More than 60 scientists and program officials from 13 countries met at the Scripps Institution of Oceanography for the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Observing System (TPOS) 2020 Workshop. The workshop, although motivated in part by the dramatic decline of NOAA's <span class="hlt">Tropical</span> Atmosphere Ocean (TAO) buoy reporting from mid-2012 to early 2014 (see http://www.bloomberg.com/news/2014-03-07/aging-el-nino-buoys-getting-fixed-as-weather-forecasts-at-risk.html), evaluated the needs for <span class="hlt">tropical</span> <span class="hlt">Pacific</span> observing and initiated efforts to develop a more resilient and integrative observing system for the future.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMPP54A..07C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMPP54A..07C"><span><span class="hlt">Tropical</span> <span class="hlt">Pacific</span> climate during the Medieval Climate Anomaly: progress and pitfalls</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cobb, K. M.; Westphal, N.; Charles, C.; Sayani, H. R.; Edwards, R. L.; Cheng, H.; Grothe, P. R.; Chen, T.; Hitt, N. T.; O'Connor, G.; Atwood, A. R.</p> <p>2016-12-01</p> <p>A vast trove of paleoclimate records indicates that the Medieval Climate Anomaly (MCA; 900-1200AD) was characterized by relative warmth throughout the Northern Hemisphere and significant hydroclimate anomalies - particularly well-resolved over North America - that posed a challenge to human populations. The global-scale nature of the climate anomalies has driven speculation that the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, with its rich spectrum of natural variability and far-reaching impact, may have undergone a prolonged reorganization during the MCA. While some key records from across the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> document significant changes in temperature and/or hydrology, a dynamically-consistent picture of the MCA <span class="hlt">tropical</span> <span class="hlt">Pacific</span> climate state has proven elusive. In particular, there are few if any robust paleoclimate constraints from the <span class="hlt">central</span> <span class="hlt">Pacific</span>, where even modest changes in ocean temperature translate into distinct patterns of global atmospheric teleconnections. Here, we present a new collection of fossil coral multi-proxy records from Christmas Island (2N, 157W) that provide robust constraints on both temperature and hydrological changes during the MCA. We employ both modern coral data, instrumental climate data, and climate model output in developing a framework for quantifying the uncertainties associated with the new fossil coral data. In doing so, we illustrate the clear benefits of modern environmental monitoring campaigns that inform the generation of paleoclimate pseudo-proxies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMPP32A..01D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMPP32A..01D"><span>Pleistocene <span class="hlt">tropical</span> <span class="hlt">Pacific</span> temperature sensitivity to radiative greenhouse gas forcing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dyck, K. A.; Ravelo, A. C.</p> <p>2011-12-01</p> <p>How high will Earth's global average surface temperature ultimately rise as greenhouse gas concentrations increase in the future? One way to tackle this question is to compare contemporaneous temperature and greenhouse gas concentration data from paleoclimate records, while considering that other radiative forcing mechanisms (e.g. changes in the amount and distribution of incoming solar radiation associated with changes in the Earth's orbital configuration) also contribute to surface temperature change. Since the sensitivity of surface temperature varies with location and latitude, here we choose a <span class="hlt">central</span> location representative of the west <span class="hlt">Pacific</span> warm pool, far from upwelling regions or surface temperature gradients in order to minimize climate feedbacks associated with high-latitude regions or oceanic dynamics. The 'steady-state' or long-term temperature change associated with greenhouse gas radiative forcing is often labeled as equilibrium (or 'Earth system') climate sensitivity to the doubling of atmospheric greenhouse gas concentration. Climate models suggest that Earth system sensitivity does not change dramatically over times when CO2 was lower or higher than the modern atmospheric value. Thus, in our investigation of the changes in <span class="hlt">tropical</span> SST, from the glacial to interglacial states when greenhouse gas forcing nearly doubled, we use Late Pleistocene paleoclimate records to constrain earth system sensitivity for the <span class="hlt">tropics</span>. Here we use Mg/Ca-paleothermometry using the foraminifera G. ruber from ODP Site 871 from the past 500 kyr in the western <span class="hlt">Pacific</span> warm pool to estimate <span class="hlt">tropical</span> <span class="hlt">Pacific</span> equilibrium climate sensitivity to a doubling of greenhouse gas concentrations to be ~4°C. This <span class="hlt">tropical</span> SST sensitivity to greenhouse gas forcing is ~1-2°C higher than that predicted by climate models of past glacial periods or future warming for the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. Equatorial <span class="hlt">Pacific</span> SST sensitivity may be higher than predicted by models for a number of reasons</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.A41L..04O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.A41L..04O"><span>The 2015/16 El Niño Event as Recorded in <span class="hlt">Central</span> <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Corals: Temperature, Hydrology, and Ocean Circulation Influences</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>O'Connor, G.; Cobb, K. M.; Sayani, H. R.; Grothe, P. R.; Atwood, A. R.; Stevenson, S.; Hitt, N. T.; Lynch-Stieglitz, J.</p> <p>2016-12-01</p> <p>The El Niño/Southern Oscillation (ENSO) of 2015/2016 was a record-breaking event in the <span class="hlt">central</span> <span class="hlt">Pacific</span>, driving profound changes in the properties of the ocean and atmosphere. Prolonged ocean warming of up to 3°C translated into a large-scale coral bleaching and mortality event on Christmas Island (2°N, 157°W) that very few individuals escaped unscathed. As part of a long-term, interdisciplinary monitoring effort underway since August 2014, we present results documenting the timing and magnitude of environmental changes on the Christmas Island reefs. In particular, we present the first coral geochemical time series spanning the last several years, using cores that were drilled from rare living coral colonies during a field expedition in April 2016, at the tail end of the event. These geochemical indicators are sensitive to both ocean temperature, salinity, and water mass properties and have been used to quantitatively reconstruct ENSO extremes of the recent [Nurhati et al., 2011] and distant [Cobb et al., 2013] past. By analyzing multiple cores from both open ocean and lagoonal settings, we are able to undertake a quantitative comparison of this event with past very strong El Niño events contained in the coral archive - including the 1940/41, 1972/73, and 1997/98 events. For the most recent event, we compare our coral geochemistry records with a rich suite of in situ environmental data, including physical and geochemical parameters collected as part of the NOAA rapid response campaign in the <span class="hlt">central</span> <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. This unique dataset not only provides physical context interpreting coral geochemical records from the <span class="hlt">central</span> <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, but allows us to assess why the 2015/2016 El Niño event was so devastating to coral reef ecosystems in this region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.A23M..06E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.A23M..06E"><span>Holocene constraints on simulated <span class="hlt">tropical</span> <span class="hlt">Pacific</span> climate</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Emile-Geay, J.; Cobb, K. M.; Carre, M.; Braconnot, P.; Leloup, J.; Zhou, Y.; Harrison, S. P.; Correge, T.; Mcgregor, H. V.; Collins, M.; Driscoll, R.; Elliot, M.; Schneider, B.; Tudhope, A. W.</p> <p>2015-12-01</p> <p>The El Niño-Southern Oscillation (ENSO) influences climate and weather worldwide, so uncertainties in its response to external forcings contribute to the spread in global climate projections. Theoretical and modeling studies have argued that such forcings may affect ENSO either via the seasonal cycle, the mean state, or extratropical influences, but these mechanisms are poorly constrained by the short instrumental record. Here we synthesize a pan-<span class="hlt">Pacific</span> network of high-resolution marine biocarbonates spanning discrete snapshots of the Holocene (past 10, 000 years of Earth's history), which we use to constrain a set of global climate model (GCM) simulations via a forward model and a consistent treatment of uncertainty. Observations suggest important reductions in ENSO variability throughout the interval, most consistently during 3-5 kyBP, when approximately 2/3 reductions are inferred. The magnitude and timing of these ENSO variance reductions bear little resemblance to those sim- ulated by GCMs, or to equatorial insolation. The <span class="hlt">central</span> <span class="hlt">Pacific</span> witnessed a mid-Holocene increase in seasonality, at odds with the reductions simulated by GCMs. Finally, while GCM aggregate behavior shows a clear inverse relationship between seasonal amplitude and ENSO-band variance in sea-surface temperature, in agreement with many previous studies, such a relationship is not borne out by these observations. Our synthesis suggests that <span class="hlt">tropical</span> <span class="hlt">Pacific</span> climate is highly variable, but exhibited millennia-long periods of reduced ENSO variability whose origins, whether forced or unforced, contradict existing explanations. It also points to deficiencies in the ability of current GCMs to simulate forced changes in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> seasonal cycle and its interaction with ENSO, highlighting a key area of growth for future modeling efforts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMPP43F..04S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMPP43F..04S"><span>Insight into the <span class="hlt">Pacific</span> Sea Surface Temperature- North American Hydroclimate Connection from an Eastern <span class="hlt">Tropical</span> North <span class="hlt">Pacific</span> Coral Record</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sanchez, S. C.; Charles, C. D.; Carriquiry, J. D.</p> <p>2015-12-01</p> <p>The last few years of record-breaking climate anomalies across North America--a resilient atmospheric ridge and extreme drought over the West Coast, and severe winters across the Midwest and East Coast regions--have been linked to anomalous <span class="hlt">Pacific</span> sea surface temperatures (Seager et al. 2014, Wang et al. 2014, Hartmann 2015). The synoptic associations prompt important questions on the relation between these unusual phenomena and extreme expressions of known <span class="hlt">Pacific</span> decadal modes, such as the North <span class="hlt">Pacific</span> Gyre Oscillation (NPGO). These questions motivate our pursuit to document multiple realizations of decadal variability in the <span class="hlt">Pacific</span>-North American region through periods of varied radiative forcing. Here we introduce a 178 year, seasonally resolved Porites coral record from Clarion Island (18N, 115W), the westernmost island of the Revillagigedo Archipelago, a region both highly influenced by NPGO SST and SSS variability and critical for NPGO <span class="hlt">tropical</span>-extratropical communication via the Seasonal Footprinting Mechanism (Vimont et al. 2003). When coupled with tree ring records from the western United States (Griffin and Anchukaitis 2014, MacDonald and Case 2005) and coral records from the <span class="hlt">central</span> <span class="hlt">tropical</span> <span class="hlt">Pacific</span> (Cobb et al. 2001), the δ18O signal from the Clarion coral offers an extended framework of coherent continental hydroclimate and oceanic variability across the <span class="hlt">Pacific</span> basin beyond the instrumental record. Over the last 200 years, we find clear commonality in the timing, magnitude and spatial expression of variability (illustrated through the NADA Atlas, Cook et al. 2004) amongst the proxy records. The strong relationship between Northeastern <span class="hlt">Pacific</span> Clarion and the <span class="hlt">Central</span> <span class="hlt">Pacific</span> Palmyra record with the North American hydroclimate records can be viewed within the mechanistic framework of the NPGO; this framework is then explored over the last millennium across intervals of varied radiative forcing.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_1");'>1</a></li> <li class="active"><span>2</span></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_2 --> <div id="page_3" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_1");'>1</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li class="active"><span>3</span></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="41"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMPP43F..04S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMPP43F..04S"><span>Insight into the <span class="hlt">Pacific</span> Sea Surface Temperature- North American Hydroclimate Connection from an Eastern <span class="hlt">Tropical</span> North <span class="hlt">Pacific</span> Coral Record</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Svendsen, J. I.; Briner, J. P.; Mangerud, J.; Hughes, A. L. C.; Young, N. E.; Vasskog, K.</p> <p>2014-12-01</p> <p>The last few years of record-breaking climate anomalies across North America--a resilient atmospheric ridge and extreme drought over the West Coast, and severe winters across the Midwest and East Coast regions--have been linked to anomalous <span class="hlt">Pacific</span> sea surface temperatures (Seager et al. 2014, Wang et al. 2014, Hartmann 2015). The synoptic associations prompt important questions on the relation between these unusual phenomena and extreme expressions of known <span class="hlt">Pacific</span> decadal modes, such as the North <span class="hlt">Pacific</span> Gyre Oscillation (NPGO). These questions motivate our pursuit to document multiple realizations of decadal variability in the <span class="hlt">Pacific</span>-North American region through periods of varied radiative forcing. Here we introduce a 178 year, seasonally resolved Porites coral record from Clarion Island (18N, 115W), the westernmost island of the Revillagigedo Archipelago, a region both highly influenced by NPGO SST and SSS variability and critical for NPGO <span class="hlt">tropical</span>-extratropical communication via the Seasonal Footprinting Mechanism (Vimont et al. 2003). When coupled with tree ring records from the western United States (Griffin and Anchukaitis 2014, MacDonald and Case 2005) and coral records from the <span class="hlt">central</span> <span class="hlt">tropical</span> <span class="hlt">Pacific</span> (Cobb et al. 2001), the δ18O signal from the Clarion coral offers an extended framework of coherent continental hydroclimate and oceanic variability across the <span class="hlt">Pacific</span> basin beyond the instrumental record. Over the last 200 years, we find clear commonality in the timing, magnitude and spatial expression of variability (illustrated through the NADA Atlas, Cook et al. 2004) amongst the proxy records. The strong relationship between Northeastern <span class="hlt">Pacific</span> Clarion and the <span class="hlt">Central</span> <span class="hlt">Pacific</span> Palmyra record with the North American hydroclimate records can be viewed within the mechanistic framework of the NPGO; this framework is then explored over the last millennium across intervals of varied radiative forcing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.A11B3022D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.A11B3022D"><span>Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Precipitation Response to Zonal SPCZ events</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Durán-Quesada, A. M.; Lintner, B. R.</p> <p>2014-12-01</p> <p>Extreme El Niño events and warming conditions in the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> have been linked to pronounced spatial displacements of the South <span class="hlt">Pacific</span> Convergence Zone known as "zonal SPCZ" events.. Using a global dataset of Lagrangian back trajectories computed with the FLEXPART model for the period 1980-2013, comprehensive analysis of the 3D circulation characteristics associated with the SPCZ is undertaken. Ten days history of along-trajectory specific humidity, potential vorticity and temperature are reconstructed for zonal SPCZ events as well as other states,, with differences related to El Niño intensity and development stage as well as the state of the Western Hemisphere Warm Pool. How zonal events influence precipitation over the Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> is examined using back trajectories, reanalysis, TRMM precipitation, and additional satellite derived cloud information. It is found that SPCZ displacements are associated with enhanced convection over the Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> in good agreement with prior work. The connection between intensification of precipitation over the eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> during zonal events and suppression of rainfall over the Maritime continent is also described.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMPP23D..08M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMPP23D..08M"><span><span class="hlt">Central</span> Equatorial <span class="hlt">Pacific</span> Sea Surface Temperatures During the Last Glacial Maximum</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Monteagudo, M. M.; Lynch-Stieglitz, J.; Schmidt, M. W.</p> <p>2017-12-01</p> <p>The state of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> ocean-atmosphere system during the Last Glacial Maximum (LGM, 19,000-23,000 years BP) remains an area of uncertainty. Spatial patterns of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> sea surface temperature (SST) offer insight into atmospheric circulation (i.e. Walker Circulation), however, few records exist for the <span class="hlt">Central</span> <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> (CTP). The few existing glacial CTP SST reconstructions indicate 1-2 °C of warming based on foraminiferal transfer functions (CLIMAP Project Members, 1976). In contrast, evidence from geochemical proxies (Mg/Ca, UK'37, TEX86) show 1-3.5 °C cooling in the eastern and western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> (e.g. MARGO Project Members, 2009). In this study we present the first Mg/Ca estimates of glacial CTP SST from a meridional sediment core transect along the Line Islands Ridge (0-7°N, 156-162 °W). We use a time slice approach to establish the magnitude of glacial-interglacial SST change between the LGM (19,000-23,0000 years BP) and the Holocene (0-10,000 years BP) using Mg/Ca in the surface-dwelling foraminifera Globigerinoides ruber. Our results indicate cooling at all latitudes, ranging between 1.2-2.7 °C (Holocene-LGM SST). Northern cores (6.83-2.77 °N) exhibit a smaller glacial-interglacial SST difference than equatorial site 20BB at 1.27 °N. The data generated thus far suggest the glacial meridional SST gradient may have been steeper, possibly as a result of increased zonal winds, equatorial upwelling, or westward expansion of the Eastern <span class="hlt">Pacific</span> Cold Tongue.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.fs.usda.gov/treesearch/pubs/24150','TREESEARCH'); return false;" href="https://www.fs.usda.gov/treesearch/pubs/24150"><span>Proceedings of the session on <span class="hlt">tropical</span> forestry for people of the <span class="hlt">Pacific</span>, XVII <span class="hlt">Pacific</span> Science Congress; May 27-28, 1991</span></a></p> <p><a target="_blank" href="http://www.fs.usda.gov/treesearch/">Treesearch</a></p> <p>Eugene C. Conrad; Leonard A. Newell</p> <p>1992-01-01</p> <p>The 17 papers in the Proceedings of the Session on <span class="hlt">Tropical</span> Forestry for People of the <span class="hlt">Pacific</span> cover the topics of the USDA Forest Service's <span class="hlt">tropical</span> forestry research, forestry research in Asia and the <span class="hlt">Pacific</span>, management of <span class="hlt">tropical</span> forests for products and energy; forest and wildlife management, the South <span class="hlt">Pacific</span> Forestry Development Programme, <span class="hlt">tropical</span>...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMPP23D..05S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMPP23D..05S"><span><span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Climate, Carbon, and Ocean Biogeochemical Response to the <span class="hlt">Central</span> American Seaway in a GFDL Earth System Model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sentman, L. T.; Dunne, J. P.; Stouffer, R. J.; Krasting, J. P.; Wittenberg, A. T.; Toggweiler, J. R.; Broccoli, A. J.</p> <p>2017-12-01</p> <p>To explore the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> climate, carbon, and ocean biogeochemical response to the shoaling and closure of the <span class="hlt">Central</span> American Seaway during the Pliocene (5.3-2.6 Ma), we performed a suite of sensitivity experiments using the Geophysical Fluid Dynamics Laboratory Earth System Model, GFDL-ESM2G, varying only the seaway widths and sill depths. These novel ESM simulations include near-final closure of the seaway with a very narrow, 1º grid cell wide opening. Net mass transport through the seaway into the Caribbean is 20.5-23.1 Sv with a deep seaway, but only 14.1 Sv for the wide/shallow seaway because of the inter-basin bi-directional horizontal mass transport. Seaway transport originates from the Antarctic Circumpolar Current in the <span class="hlt">Pacific</span> and rejoins it in the South Atlantic, reducing the Indonesian Throughflow and transporting heat and salt southward into the South Atlantic, in contrast to present-day and previous seaway simulations. <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> mean climate and interannual variability is sensitive to the seaway shoaling, with the largest response to the wider/deeper seaway. In the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, the top 300-m warms 0.4-0.8°C, the equatorial east-west sea surface temperature gradient increases, the north-south sea surface temperature asymmetry at 110°W decreases, thermocline deepens 5-11 m, and the east-west thermocline gradient increases. In the Niño-3 region, ENSO amplitude increases, skewed toward more cold (La Niña) events, El Niño and La Niña develops earlier ( 3 months), the annual cycle weakens and the semi-annual and interannual cycles strengthen from increased symmetry of the north-south sea surface temperature gradient, and atmospheric global teleconnections strengthen with the seaway. The increase in global ocean overturning with the seaway results in a younger average ocean ideal age, reduced dissolved inorganic carbon inventory and marine net primary productivity, and altered inter-basin patterns of surface sediment carbonate</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009OcSci...5..313A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009OcSci...5..313A"><span>Regional impacts of ocean color on <span class="hlt">tropical</span> <span class="hlt">Pacific</span> variability</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Anderson, W.; Gnanadesikan, A.; Wittenberg, A.</p> <p>2009-08-01</p> <p>The role of the penetration length scale of shortwave radiation into the surface ocean and its impact on <span class="hlt">tropical</span> <span class="hlt">Pacific</span> variability is investigated with a fully coupled ocean, atmosphere, land and ice model. Previous work has shown that removal of all ocean color results in a system that tends strongly towards an El Niño state. Results from a suite of surface chlorophyll perturbation experiments show that the mean state and variability of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> is highly sensitive to the concentration and distribution of ocean chlorophyll. Setting the near-oligotrophic regions to contain optically pure water warms the mean state and suppresses variability in the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. Doing the same above the shadow zones of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> also warms the mean state but enhances the variability. It is shown that increasing penetration can both deepen the pycnocline (which tends to damp El Niño) while shifting the mean circulation so that the wind response to temperature changes is altered. Depending on what region is involved this change in the wind stress can either strengthen or weaken ENSO variability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009OcScD...6..243A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009OcScD...6..243A"><span>Regional impacts of ocean color on <span class="hlt">tropical</span> <span class="hlt">Pacific</span> variability</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Anderson, W.; Gnanadesikan, A.; Wittenberg, A.</p> <p>2009-02-01</p> <p>The role of the penetration length scale of shortwave radiation into the surface ocean and its impact on <span class="hlt">tropical</span> <span class="hlt">Pacific</span> variability is investigated with a fully coupled ocean, atmosphere, land and ice model. Previous work has shown that removal of all ocean color results in a system that tends strongly towards an El Niño state. Results from a suite of surface chlorophyll perturbation experiments show that the mean state and variability of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> is highly sensitive to the concentration and distribution of ocean chlorophyll. Setting the near-oligotrophic regions to contain optically pure water warms the mean state and suppresses variability in the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. Doing the same above the shadow zones of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> also warms the mean state but enhances the variability. It is shown that increasing penetration can both deepen the pycnocline (which tends to damp El Niño) while shifting the mean circulation so that the wind response to temperature changes is altered. Depending on what region is involved this change in the wind stress can either strengthen or weaken ENSO variability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16..823M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16..823M"><span>Comparaison of last centuries variability in the eastern and <span class="hlt">central</span> <span class="hlt">Pacific</span> reconstructed from massive coral geochemical tracers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Moreau, Melanie; Corrège, Thierry; Cole, Julie; Le Cornec, Florence; Edwards, Lawrence; Cheng, Hai; Charlier, Karine</p> <p>2014-05-01</p> <p>The <span class="hlt">tropical</span> <span class="hlt">Pacific</span> is under the influence of different climate modes (from the seasonal to the decadal scale) and, through teleconnections, affects the global climate. At the seasonal scale the latitudinal migration of the Intertropical Convergence Zone (ITCZ) drive the hydrological dynamic of the <span class="hlt">tropical</span> zone. The <span class="hlt">tropical</span> <span class="hlt">Pacific</span> is also a place of strong and variable zonal gradients due to the El Niño Southern Oscillation phenomenon (ENSO) at the interannual scale. A good amount of data is available in the western and the <span class="hlt">central</span> part of the <span class="hlt">Pacific</span> to reconstruct climatic parameters such as sea surface temperature (SST) and sea surface salinity (SSS) while there is a striking lack of data in the eastern part. To better estimate the zonal gradients in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> and the different climatic processes in the last two centuries, we present geochemical results (Sr/Ca and δ18O) obtained from aragonitic coral skeletons (Porites genus) from Clipperton atoll (10° N, 109° W) and the Marquesas Islands (10° S, 140° W). Clipperton being the only atoll located in the northern part of the ITCZ latitudinal migration area, information about eastern <span class="hlt">Pacific</span> hydrological cycle and advection can be obtained. On the other hand, the precise chronology of the Clipperton coral and the comparaison with the records from the Marquesas Islands allows us to calculate SST gradients between the eastern and <span class="hlt">central</span> <span class="hlt">Pacific</span>. We will discuss about the recent theory of an El Niño-like condition triggered by a slowdown of the equatorial Walker circulation under global warming. We will also discuss about the evolution (frequency and intensity) of the two differents 'flavours' of El Niño (e.g. the canonical eastern El Niño and the <span class="hlt">central</span> El Niño Modoki) through the 20thcentury. Indeed the canonical El Niño is characterised by a maximum SST anomaly in the eastern <span class="hlt">Pacific</span> while the El Niño Modoki is characterised by a maximum SST anomaly persisting in the <span class="hlt">central</span> <span class="hlt">Pacific</span>. A</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.A31E0112Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.A31E0112Y"><span>Decadal Variation's Offset of Global Warming in Recent <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Climate</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yeo, S. R.; Yeh, S. W.; Kim, K. Y.; Kim, W.</p> <p>2015-12-01</p> <p>Despite the increasing greenhouse gas concentration, there is no significant warming in the sea surface temperature (SST) over the <span class="hlt">tropical</span> eastern <span class="hlt">Pacific</span> since about 2000. This counterintuitive observation has generated substantial interest in the role of low-frequency variation over the <span class="hlt">Pacific</span> Ocean such as <span class="hlt">Pacific</span> Decadal Oscillation (PDO) or Interdecadal <span class="hlt">Pacific</span> Oscillation (IPO). Therefore, it is necessary to appropriately separate low-frequency variability and global warming from SST records. Here we present three primary modes of global SST as a secular warming trend, a low-frequency variability, and a biennial oscillation through the use of novel statistical method. By analyzing temporal behavior of the three-mode, it is found that the opposite contributions of secular warming trend and cold phase of low-frequency variability since 1999 account for the warming hiatus in the <span class="hlt">tropical</span> eastern <span class="hlt">Pacific</span>. This result implies that the low-frequency variability modulates the manifestation of global warming signal in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> SST. Furthermore, if the low-frequency variability turns to a positive phase, warming in the <span class="hlt">tropical</span> eastern <span class="hlt">Pacific</span> will be amplified and also strong El Niño events will occur more frequently in the near future.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1996CorRe..15..133L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1996CorRe..15..133L"><span>Indo-<span class="hlt">Pacific</span> echinoids in the <span class="hlt">tropical</span> eastern <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lessios, H. A.; Kessing, B. D.; Wellington, G. M.; Graybeal, A.</p> <p>1996-06-01</p> <p>The existing literature reports that only one species of Indo-<span class="hlt">Pacific</span> echinoid ( Echinometra oblonga), occurs in the eastern <span class="hlt">Pacific</span>. In this study we confirm the presence of this species at Islas Revillagigedo and also report the presence of two species of Echinothrix (a genus hitherto unknown outside the Indo-<span class="hlt">Pacific</span>) at Isla del Coco and at Clipperton Island. We also present evidence from isozymes and from mitochondrial DNA sequences indicating that at least one individual of Diadema at Clipperton may belong to a maternal lineage characteristic of the west <span class="hlt">Pacific</span> species D. savignyi. These data are consistent with the hypothesis that the observed populations of Indo-<span class="hlt">Pacific</span> echinoid species are recent arrivals to the eastern <span class="hlt">Pacific</span>, as opposed to the view that they are relicts of Tethyan pan-<span class="hlt">tropical</span> distributions. Echinothrix diadema, in particular, may have arrived at Isla del Coco during the 1982-1983 El Nifio. In addition to Indo-<span class="hlt">Pacific</span> species, Clipperton, Isla del Coco and the Revillagigedos contain a complement of eastern <span class="hlt">Pacific</span> echinoids. The echinoid faunas of these islands should, therefore, be regarded as mixtures of two biogeographic provinces. Though none of the Indo-<span class="hlt">Pacific</span> species are known to have reached the coast of the American mainland, their presence at the offshore islands of the eastern <span class="hlt">Pacific</span> suggests that, for some echinoids, the East <span class="hlt">Pacific</span> Barrier is not as formidable an obstacle to migration as was previously thought.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006Natur.441...73V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006Natur.441...73V"><span>Weakening of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> atmospheric circulation due to anthropogenic forcing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vecchi, Gabriel A.; Soden, Brian J.; Wittenberg, Andrew T.; Held, Isaac M.; Leetmaa, Ants; Harrison, Matthew J.</p> <p>2006-05-01</p> <p>Since the mid-nineteenth century the Earth's surface has warmed, and models indicate that human activities have caused part of the warming by altering the radiative balance of the atmosphere. Simple theories suggest that global warming will reduce the strength of the mean <span class="hlt">tropical</span> atmospheric circulation. An important aspect of this <span class="hlt">tropical</span> circulation is a large-scale zonal (east-west) overturning of air across the equatorial <span class="hlt">Pacific</span> Ocean-driven by convection to the west and subsidence to the east-known as the Walker circulation. Here we explore changes in <span class="hlt">tropical</span> <span class="hlt">Pacific</span> circulation since the mid-nineteenth century using observations and a suite of global climate model experiments. Observed Indo-<span class="hlt">Pacific</span> sea level pressure reveals a weakening of the Walker circulation. The size of this trend is consistent with theoretical predictions, is accurately reproduced by climate model simulations and, within the climate models, is largely due to anthropogenic forcing. The climate model indicates that the weakened surface winds have altered the thermal structure and circulation of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean. These results support model projections of further weakening of <span class="hlt">tropical</span> atmospheric circulation during the twenty-first century.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMPP43D..06G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMPP43D..06G"><span>Multiproxy Reduced-Dimension Reconstruction of Holocene <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> SST Fields and Indian Monsoon Variability</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gill, E.; Rajagopalan, B.; Molnar, P. H.; Marchitto, T. M., Jr.; Kushnir, Y.</p> <p>2016-12-01</p> <p>We develop a multiproxy reduced-dimension methodology that blends magnesium calcium (Mg/Ca) and alkenone (UK'37) paleo sea surface temperature (SST) records from the eastern and western equatorial <span class="hlt">Pacific</span> to recreate snapshots of full field SSTs and zonal wind anomalies from 10 to 2 ka BP in 2000-year increments. In the reconstruction, the zonal SST difference (average west <span class="hlt">Pacific</span> SST minus average east <span class="hlt">Pacific</span> SST) is largest at 10 ka (0.26°C), with coldest SST anomalies of -0.9°C in the eastern equatorial <span class="hlt">Pacific</span> and concurrent easterly maximum zonal wind anomalies of 7 m s-1 throughout the <span class="hlt">central</span> <span class="hlt">Pacific</span>. From 10 to 2 ka, the entire equatorial <span class="hlt">Pacific</span> warms, but at a faster rate in the east than in the west. These patterns are broadly consistent with previous inferences of reduced El Niño-Southern Oscillation variability associated with a cooler and/or "La Niña-like" state during the early to middle Holocene. At present there is a strong negative correlation between <span class="hlt">tropical</span> <span class="hlt">pacific</span> SSTs and Indian summer monsoon strength. Assuming ENSO-monsoon teleconnections were the same during early Holocene, we would expect a cooler <span class="hlt">tropical</span> <span class="hlt">Pacific</span> to enhance the summer Indian monsoon. To test this idea, we used the same <span class="hlt">tropical</span> <span class="hlt">Pacific</span> SST proxy records and a similar reduced-dimension technique to reconstruct fields of Arabian Sea wind-stress curl and Indian summer monsoon precipitation. Reconstructions for 10 ka reveal wind-stress curl anomalies of 30% greater than present day off the coastlines of Oman and Yemen, which suggest greater coastal upwelling and an enhanced monsoon jet during this time. Spatial rainfall reconstructions reveal the greatest difference in precipitation at 10 ka over the core monsoon region ( 20-60% greater than present day). Specifically, reconstructions from 10 ka reveal 40-60% greater rainfall over North West India, a region home to abundant paleo-lake records spanning the Holocene but is at present remarkably dry ( 200-450 mm of annual</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUOS.B24A0308K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUOS.B24A0308K"><span>Reduced efficiency of biological pump in the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kim, D.</p> <p>2016-02-01</p> <p>The western <span class="hlt">Pacific</span> warm pool (WPWP) area has recently extended, which may influence considerably the marine ecosystems in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. Here, we show the long-term trends in particle fluxes associated with the marine ecosystem changes in WPWP area. Total mass and biogenic fluxes have an annually decreasing trend from 2009 to 2014, which is mainly derived by the decrease in the biomass of N2 fixing cyanobacteria during summer. In the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, the decrease in the biomass of N2 fixing cyanobacteria is attributed to the decrease of phosphate concentration associated with the shoaling of the winter mixed layer depth. The efficiency of biological pump has recently reduced in the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, which might suppress the oceanic sequestration of atmospheric CO2 and thereby accelerate the global warming in the future.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.A53B0279S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.A53B0279S"><span>Connections between the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean, Arctic sea ice, and anomalous northeastern <span class="hlt">Pacific</span> ridging</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Swain, D. L.; Singh, D.; Horton, D. E.; Mankin, J. S.; Ballard, T.; Thomas, L. N.; Diffenbaugh, N. S.</p> <p>2016-12-01</p> <p>The ongoing and severe drought in California is linked to the multi-year persistence of anomalously strong ridging along the west coast of North America, which has deflected the <span class="hlt">Pacific</span> storm track north of its climatological mean position. Recent work has shown that that highly amplified and strongly meridional atmospheric flow patterns in this region similar to the "Ridiculously Resilient Ridge" have become more common in recent decades. Previous investigations have suggested multiple possible contributors to this conspicuous atmospheric anomaly—including remote teleconnections to unusual <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean warmth and/or reduced Arctic sea ice, internal (natural) atmospheric variability, and anthropogenic forcing due to greenhouse gas emissions. Here, we explore observed relationships between mid-tropospheric atmospheric structure in this region and five hypothesized surface forcings: sea ice extent in the (1) Barents/Kara and (2) Beaufort/Chukchi regions, and sea surface temperatures in the (3) extratropical northeastern <span class="hlt">Pacific</span> Ocean, (4) western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean, and (5) eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean. Using a predictive model based upon these observed relationships, we also investigate whether the failure of the powerful 2015-2016 El Niño event to bring above-average precipitation to California could have been predicted based upon these teleconnections.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ClDy...45.2033C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ClDy...45.2033C"><span>Intensified impact of <span class="hlt">tropical</span> Atlantic SST on the western North <span class="hlt">Pacific</span> summer climate under a weakened Atlantic thermohaline circulation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Wei; Lee, June-Yi; Lu, Riyu; Dong, Buwen; Ha, Kyung-Ja</p> <p>2015-10-01</p> <p>The <span class="hlt">tropical</span> North Atlantic (TNA) sea surface temperature (SST) has been identified as one of regulators on the boreal summer climate over the western North <span class="hlt">Pacific</span> (WNP), in addition to SSTs in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> and Indian Oceans. The major physical process proposed is that the TNA warming induces a pair of cyclonic circulation anomaly over the eastern <span class="hlt">Pacific</span> and negative precipitation anomalies over the eastern to <span class="hlt">central</span> <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, which in turn lead to an anticyclonic circulation anomaly over the western to <span class="hlt">central</span> North <span class="hlt">Pacific</span>. This study further demonstrates that the modulation of the TNA warming to the WNP summer climate anomaly tends to be intensified under background of the weakened Atlantic thermohaline circulation (THC) by using a water-hosing experiment. The results suggest that the weakened THC induces a decrease in thermocline depth over the TNA region, resulting in the enhanced sensitivity of SST variability to wind anomalies and thus intensification of the interannual variation of TNA SST. Under the weakened THC, the atmospheric responses to the TNA warming are westward shifted, enhancing the anticyclonic circulation and negative precipitation anomaly over the WNP. This study supports the recent finding that the negative phase of the Atlantic multidecadal oscillation after the late 1960s has been favourable for the strengthening of the connection between TNA SST variability and WNP summer climate and has important implications for seasonal prediction and future projection of the WNP summer climate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010GeoRL..3718802G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010GeoRL..3718802G"><span>How ocean color can steer <span class="hlt">Pacific</span> <span class="hlt">tropical</span> cyclones</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gnanadesikan, Anand; Emanuel, Kerry; Vecchi, Gabriel A.; Anderson, Whit G.; Hallberg, Robert</p> <p>2010-09-01</p> <p>Because ocean color alters the absorption of sunlight, it can produce changes in sea surface temperatures with further impacts on atmospheric circulation. These changes can project onto fields previously recognized to alter the distribution of <span class="hlt">tropical</span> cyclones. If the North <span class="hlt">Pacific</span> subtropical gyre contained no absorbing and scattering materials, the result would be to reduce subtropical cyclone activity in the subtropical Northwest <span class="hlt">Pacific</span> by 2/3, while concentrating cyclone tracks along the equator. Predicting <span class="hlt">tropical</span> cyclone activity using coupled models may thus require consideration of the details of how heat moves into the upper thermocline as well as biogeochemical cycling.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20020080601','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20020080601"><span>Interannual Variability of the Bimodal Distribution of Summertime Rainfall Over <span class="hlt">Central</span> America and <span class="hlt">Tropical</span> Storm Activity in the Far-Eastern <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Curtis, Scott; Starr, David OC. (Technical Monitor)</p> <p>2002-01-01</p> <p>The summer climate of southern Mexico and <span class="hlt">Central</span> America is characterized by a mid summer drought (MSD), where rainfall is reduced by 40% in July as compared to June and September. A mid-summer reduction in the climatological number of eastern <span class="hlt">Pacific</span> <span class="hlt">tropical</span> cyclones has also been noted. Little is understood about the climatology and interannual variability of these minima. The present study uses a novel approach to quantify the bimodal distribution of summertime rainfall for the globe and finds that this feature of the annual cycle is most extreme over Pan America and adjacent oceans. One dominant interannual signal in this region occurs the summer before a strong winter El Nino/Southern Oscillation ENSO. Before El Nino events the region is dry, the MSD is strong and centered over the ocean, and the mid-summer minimum in <span class="hlt">tropical</span> cyclone frequency is most pronounced. This is significantly different from Neutral cases (non-El Nino and non-La Nina) when the MSD is weak and positioned over the land bridge. The MSD is highly variable for La Nina years, and there is not an obvious mid-summer minimum in the number of <span class="hlt">tropical</span> cyclones.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.A43I0381P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.A43I0381P"><span>The Teleconnection Between Atlantic Sea Surface Temperature and Eastern <span class="hlt">Pacific</span> <span class="hlt">Tropical</span> Cyclones</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Patricola, C. M.; Saravanan, R.; Chang, P.</p> <p>2016-12-01</p> <p>The El Niño-Southern Oscillation (ENSO) is a major source of seasonal <span class="hlt">tropical</span> cyclone (TC) predictability, in both local and remote ocean basins. Unusually warm eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> sea-surface temperature (SST) during El Niño tends not only to enhance local TC activity in the eastern North <span class="hlt">Pacific</span> (ENP) but also to suppress Atlantic TCs via well-known teleconnections. Here, we demonstrate that Atlantic SST variability likewise exerts a significant influence on remote TC activity in the eastern <span class="hlt">Pacific</span> basin using observations and 27 km resolution <span class="hlt">tropical</span> channel model simulations. Observed and simulated accumulated cyclone energy in the ENP is substantially reduced during the positive phase of the Atlantic Meridional Mode (AMM), which is characterized by warm and cool SST anomalies in the northern and southern <span class="hlt">tropical</span> Atlantic respectively, and vice versa during the cool AMM phase. We find that the observed anti-correlation in seasonal TC activity between the Atlantic and ENP basins is driven by interannual climate variability in both the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> (ENSO) and Atlantic (AMM). The physical mechanisms that drive the teleconnection between Atlantic SST and ENP TC activity will also be presented. This work provides information that can be used to improve seasonal forecasts and future projections of ENP <span class="hlt">tropical</span> cyclone activity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002JGRD..107.8403K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002JGRD..107.8403K"><span>Reactive nitrogen over the <span class="hlt">tropical</span> western <span class="hlt">Pacific</span>: Influence from lightning and biomass burning during BIBLE A</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Koike, M.; Kondo, Y.; Kita, K.; Nishi, N.; Liu, S. C.; Blake, D.; Ko, M.; Akutagawa, D.; Kawakami, S.; Takegawa, N.; Zhao, Y.; Ogawa, T.</p> <p>2002-02-01</p> <p>The Biomass Burning and Lightning Experiment phase A (BIBLE A) aircraft campaign was carried out over the <span class="hlt">tropical</span> western <span class="hlt">Pacific</span> in September and October 1998. During this period, biomass burning activity in Indonesia was quite weak. Mixing ratios of NOx and NOy in air masses that had crossed over the Indonesian islands within 3 days prior to the measurement (Indonesian air masses) were systematically higher than those in air masses originating from the <span class="hlt">central</span> <span class="hlt">Pacific</span> (<span class="hlt">tropical</span> air masses). Sixty percent of the Indonesian air masses at 9-13 km (upper troposphere, UT) originated from the <span class="hlt">central</span> <span class="hlt">Pacific</span>. The differences in NOy mixing ratio between these two types of air masses were likely due to processes that occurred while air masses were over the Islands. Evidence presented in this paper suggests convection carries material from the surface, and NO is produced from lightning. At altitudes below 3 km (lower troposphere, LT), typical gradient of NOx and NOy to CO (dNOy/dCO and dNOx/dCO) was smaller than that in the biomass burning plumes and in urban areas, suggesting that neither source has a dominant influence. When the CO-NOx and CO-NOy relationships in the UT are compared to the reference relationships chosen for the LT, the NOx and NOy values are higher by 40-60 pptv (80% of NOx) and 70-100 pptv (50% of NOy). This difference is attributed to in situ production of NO by lightning. Analyses using air mass trajectories and geostationary meteorological satellite (GMS) derived cloud height data show that convection over land, which could be accompanied by lightning activity, increases the NOx values, while convection over the ocean generally lowers the NOx level. These processes are found to have a significant impact on the O3 production rate over the <span class="hlt">tropical</span> western <span class="hlt">Pacific</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003JGRD..108.8403K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003JGRD..108.8403K"><span>Reactive nitrogen over the <span class="hlt">tropical</span> western <span class="hlt">Pacific</span>: Influence from lightning and biomass burning during BIBLE A</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Koike, M.; Kondo, Y.; Kita, K.; Nishi, N.; Liu, S. C.; Blake, D.; Ko, M.; Akutagawa, D.; Kawakami, S.; Takegawa, N.; Zhao, Y.; Ogawa, T.</p> <p>2003-02-01</p> <p>The Biomass Burning and Lightning Experiment phase A (BIBLE A) aircraft campaign was carried out over the <span class="hlt">tropical</span> western <span class="hlt">Pacific</span> in September and October 1998. During this period, biomass burning activity in Indonesia was quite weak. Mixing ratios of NOx and NOy in air masses that had crossed over the Indonesian islands within 3 days prior to the measurement (Indonesian air masses) were systematically higher than those in air masses originating from the <span class="hlt">central</span> <span class="hlt">Pacific</span> (<span class="hlt">tropical</span> air masses). Sixty percent of the Indonesian air masses at 9-13 km (upper troposphere, UT) originated from the <span class="hlt">central</span> <span class="hlt">Pacific</span>. The differences in NOy mixing ratio between these two types of air masses were likely due to processes that occurred while air masses were over the Islands. Evidence presented in this paper suggests convection carries material from the surface, and NO is produced from lightning. At altitudes below 3 km (lower troposphere, LT), typical gradient of NOx and NOy to CO (dNOy/dCO and dNOx/dCO) was smaller than that in the biomass burning plumes and in urban areas, suggesting that neither source has a dominant influence. When the CO-NOx and CO-NOy relationships in the UT are compared to the reference relationships chosen for the LT, the NOx and NOy values are higher by 40-60 pptv (80% of NOx) and 70-100 pptv (50% of NOy). This difference is attributed to in situ production of NO by lightning. Analyses using air mass trajectories and geostationary meteorological satellite (GMS) derived cloud height data show that convection over land, which could be accompanied by lightning activity, increases the NOx values, while convection over the ocean generally lowers the NOx level. These processes are found to have a significant impact on the O3 production rate over the <span class="hlt">tropical</span> western <span class="hlt">Pacific</span>.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_1");'>1</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li class="active"><span>3</span></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_3 --> <div id="page_4" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li class="active"><span>4</span></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="61"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JGRC..123.2037G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JGRC..123.2037G"><span>Reconstructing <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Sea Level Variability for the Period 1961-2002 Using a Linear Multimode Model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Greatbatch, Richard J.; Zhu, Xiaoting; Claus, Martin</p> <p>2018-03-01</p> <p>Monthly mean sea level anomalies in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> for the period 1961-2002 are reconstructed using a linear, multimode model driven by monthly mean wind stress anomalies from the NCEP/NCAR and ERA-40 reanalysis products. Overall, the sea level anomalies reconstructed by both wind stress products agree well with the available tide gauge data, although with poor performance at Kanton Island in the western-<span class="hlt">central</span> equatorial <span class="hlt">Pacific</span> and reduced amplitude at Christmas Island. The reduced performance is related to model error in locating the pivot point in sea level variability associated with the so-called "tilt" mode. We present evidence that the pivot point was further west during the period 1993-2014 than during the period 1961-2002 and attribute this to a persistent upward trend in the zonal wind stress variance along the equator west of 160° W throughout the period 1961-2014. Experiments driven by the zonal component of the wind stress alone reproduce much of the trend in sea level found in the experiments driven by both components of the wind stress. The experiments show an upward trend in sea level in the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> over the period 1961-2002, but with a much stronger upward trend when using the NCEP/NCAR product. We argue that the latter is related to an overly strong eastward trend in zonal wind stress in the eastern-<span class="hlt">central</span> <span class="hlt">Pacific</span> that is believed to be a spurious feature of the NCEP/NCAR product.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018GeoRL..45.3274M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018GeoRL..45.3274M"><span>Unprecedented 2015/2016 Indo-<span class="hlt">Pacific</span> Heat Transfer Speeds Up <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Heat Recharge</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mayer, Michael; Alonso Balmaseda, Magdalena; Haimberger, Leopold</p> <p>2018-04-01</p> <p>El Niño events are characterized by anomalously warm <span class="hlt">tropical</span> <span class="hlt">Pacific</span> surface waters and concurrent ocean heat discharge, a precursor of subsequent cold La Niña conditions. Here we show that El Niño 2015/2016 departed from this norm: despite extreme peak surface temperatures, <span class="hlt">tropical</span> <span class="hlt">Pacific</span> (30°N-30°S) upper ocean heat content increased by 9.6 ± 1.7 ZJ (1 ZJ = 1021 J), in stark contrast to the previous strong El Niño in 1997/1998 (-11.5 ± 2.9 ZJ). Unprecedented reduction of Indonesian Throughflow volume and heat transport played a key role in the anomalous 2015/2016 event. We argue that this anomaly is linked with the previously documented intensified warming and associated rising sea levels in the Indian Ocean during the last decade. Additionally, increased absorption of solar radiation acted to dampen <span class="hlt">Pacific</span> ocean heat content discharge. These results explain the weak and short-lived La Niña conditions in 2016/2017 and indicate the need for realistic representation of Indo-<span class="hlt">Pacific</span> energy transfers for skillful seasonal-to-decadal predictions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ClDy...49..113C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ClDy...49..113C"><span>Relationship between eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> cooling and recent trends in the Southern Hemisphere zonal-mean circulation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Clem, Kyle R.; Renwick, James A.; McGregor, James</p> <p>2017-07-01</p> <p>During 1979-2014, eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> sea surface temperatures significantly cooled, which has generally been attributed to the transition of the <span class="hlt">Pacific</span> Decadal Oscillation to its negative phase after 1999. We find the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> cooling to be associated with: (1) an intensified Walker Circulation during austral summer (December-February, DJF) and autumn (March-May, MAM); (2) a weakened South <span class="hlt">Pacific</span> Hadley cell and subtropical jet during MAM; and (3) a strengthening of the circumpolar westerlies between 50 and 60°S during DJF and MAM. Observed cooling in the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> is linearly congruent with 60-80 % of the observed Southern Hemisphere positive zonal-mean zonal wind trend between 50 and 60°S during DJF ( 35 % of the interannual variability), and around half of the observed positive zonal-mean zonal wind trend during MAM ( 15 % of the interannual variability). Although previous studies have linked the strengthened DJF and MAM circumpolar westerlies to stratospheric ozone depletion and increasing greenhouse gases, we note that the continuation of the positive SAM trends into the twenty-first century is partially associated with eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> cooling, especially during MAM when zonal wind anomalies associated with eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> cooling project strongly onto the observed trends. Outside of DJF and MAM, eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> cooling is associated with opposing zonal wind anomalies over the <span class="hlt">Pacific</span> and Indian sectors, which we infer is the reason for the absence of significant positive SAM trends outside of DJF and MAM despite significant eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> cooling seen during all seasons.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatGe...9..669K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatGe...9..669K"><span>The <span class="hlt">tropical</span> <span class="hlt">Pacific</span> as a key pacemaker of the variable rates of global warming</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kosaka, Yu; Xie, Shang-Ping</p> <p>2016-09-01</p> <p>Global mean surface temperature change over the past 120 years resembles a rising staircase: the overall warming trend was interrupted by the mid-twentieth-century big hiatus and the warming slowdown since about 1998. The Interdecadal <span class="hlt">Pacific</span> Oscillation has been implicated in modulations of global mean surface temperatures, but which part of the mode drives the variability in warming rates is unclear. Here we present a successful simulation of the global warming staircase since 1900 with a global ocean-atmosphere coupled model where <span class="hlt">tropical</span> <span class="hlt">Pacific</span> sea surface temperatures are forced to follow the observed evolution. Without prescribed <span class="hlt">tropical</span> <span class="hlt">Pacific</span> variability, the same model, on average, produces a continual warming trend that accelerates after the 1960s. We identify four events where the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> decadal cooling markedly slowed down the warming trend. Matching the observed spatial and seasonal fingerprints we identify the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> as a key pacemaker of the warming staircase, with radiative forcing driving the overall warming trend. Specifically, <span class="hlt">tropical</span> <span class="hlt">Pacific</span> variability amplifies the first warming epoch of the 1910s-1940s and determines the timing when the big hiatus starts and ends. Our method of removing internal variability from the observed record can be used for real-time monitoring of anthropogenic warming.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ClDy...49.1321D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ClDy...49.1321D"><span>Linking a sea level pressure anomaly dipole over North America to the <span class="hlt">central</span> <span class="hlt">Pacific</span> El Niño</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ding, Ruiqiang; Li, Jianping; Tseng, Yu-heng; Sun, Cheng; Zheng, Fei</p> <p>2017-08-01</p> <p>This study demonstrates the close connection between the north-south dipole pattern of sea level pressure anomalies over northeastern North America to the western <span class="hlt">tropical</span> North Atlantic, referred to as the North American dipole (NAD), and the <span class="hlt">central</span> <span class="hlt">Pacific</span> (CP)-type El Niño a year later. In contrast to other ENSO precursors, such as the North <span class="hlt">Pacific</span> Oscillation (NPO) and <span class="hlt">Pacific</span>-North America (PNA) pattern, the NAD appears more closely related to the CP-type El Niño than to the eastern <span class="hlt">Pacific</span> (EP)-type El Niño, indicating that the NAD may serve as a unique precursor for the CP El Niño. The wintertime NAD induces sea surface temperature anomalies in the northern <span class="hlt">tropical</span> Atlantic (NTA), which subsequently play an important role in developing the CP El Niño-like pattern in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> over the course of the following year. It appears that the NAD influence on CP El Niño involves air-sea interaction over several major basins, including the subtropical/<span class="hlt">tropical</span> <span class="hlt">Pacific</span> and the NTA. Additional analysis indicates that the correlation of either the NAD index or the NPO index with the CP El Niño state a year later depends on the status of the other index. When the wintertime NAD index is of the opposite sign to the simultaneous NPO index, the correlation of the NAD or NPO index with the Niño4 index becomes much weaker.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25848968','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25848968"><span>Trans-<span class="hlt">Pacific</span> RAD-Seq population genomics confirms introgressive hybridization in Eastern <span class="hlt">Pacific</span> Pocillopora corals.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Combosch, David J; Vollmer, Steven V</p> <p>2015-07-01</p> <p>Discrepancies between morphology-based taxonomy and phylogenetic systematics are common in Scleractinian corals. In Pocillopora corals, nine recently identified genetic lineages disagree fundamentally with the 17 recognized Pocillopora species, including 5 major Indo-<span class="hlt">Pacific</span> reef-builders. Pocillopora corals hybridize in the <span class="hlt">Tropical</span> Eastern <span class="hlt">Pacific</span>, so it is possible that some of the disagreement between the genetics and taxonomy may be due to introgressive hybridization. Here we used 6769 genome-wide SNPs from Restriction-site Associated DNA Sequencing (RAD-Seq) to conduct phylogenomic comparisons among three common, Indo-<span class="hlt">Pacific</span> Pocillopora species - P. damicornis, P. eydouxi and P. elegans - within and between populations in the <span class="hlt">Tropical</span> Eastern <span class="hlt">Pacific</span> (TEP) and the <span class="hlt">Central</span> <span class="hlt">Pacific</span>. Genome-wide RAD-Seq comparisons of <span class="hlt">Central</span> and TEP Pocillopora confirm that the morphospecies P. damicornis, P. eydouxi and P. elegans are not monophyletic, but instead fall into three distinct genetic groups. However, hybrid samples shared fixed alleles with their respective parental species and, even without strict monophyly, P. damicornis share a common set of 33 species-specific alleles across the <span class="hlt">Pacific</span>. RAD-Seq data confirm the pattern of one-way introgressive hybridization among TEP Pocillopora, suggesting that introgression may play a role in generating shared, polyphyletic lineages among currently recognized Pocillopora species. Levels of population differentiation within genetic lineages indicate significantly higher levels of population differentiation in the <span class="hlt">Tropical</span> Eastern <span class="hlt">Pacific</span> than in the <span class="hlt">Central</span> West <span class="hlt">Pacific</span>. Copyright © 2015 Elsevier Inc. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19990088163&hterms=sensitivity+scale&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dsensitivity%2Bscale','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19990088163&hterms=sensitivity+scale&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dsensitivity%2Bscale"><span>Sensitivity of the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Ocean to Precipitation Induced Freshwater Flux</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Yang, Song; Lau, K.-M.; Schopf, Paul S.</p> <p>1999-01-01</p> <p>We have performed a series of experiments using an ocean model to study the sensitivity of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean to variations in precipitation induced freshwater fluxes. Variations in these fluxes arise from natural causes on all time scales. In addition, estimates of these fluxes are uncertain because of differences among measurement techniques. The model used is a quasi-isopycnal model, covering the <span class="hlt">Pacific</span> from 40 S to 40 N. The surface forcing is constructed from observed wind stress, evaporation, precipitation, and surface temperature (SST) fields. The heat flux is produced with an iterative technique so as to maintain the model close to the observed climatology, but with only a weak damping to that climatology. Climatological estimates of evaporation are combined with various estimates of precipitation to determine the net surface freshwater flux. Results indicate that increased freshwater input decreases salinity as expected, but increases temperatures in the upper ocean. Using the freshwater flux estimated from the Microwave Sounding Unit leads to a warming of up to 0.6 C in the western <span class="hlt">Pacific</span> over a case with zero net freshwater flux. SST is sensitive to the discrepancies among different precipitation observations, with root-mean-square differences in SST on the order of 0.2-0.3 C. The change in SST is more pronounced in the eastern <span class="hlt">Pacific</span>, with differences of over 1 C found among the various precipitation products. Interannual variation in precipitation during El Nino events leads to increased warming. During the winter of 1982-83, freshwater flux accounts for about 0.4 C (approximately 10-15% of the maximum warming) of the surface warming in the <span class="hlt">central</span>-eastern <span class="hlt">Pacific</span>. Thus, the error of SST caused by the discrepancies in precipitation products is more than half of the SST anomaly produced by the interannual variability of observed precipitation. Further experiments, in which freshwater flux anomalies are imposed in the western, <span class="hlt">central</span>, and eastern</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20160002942','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20160002942"><span>Airborne <span class="hlt">Tropical</span> TRopopause EXperiment (ATTREX) 2014 Western <span class="hlt">Pacific</span> Campaign</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Jensen, E.; Pfister, L.</p> <p>2014-01-01</p> <p>The NASA Airborne <span class="hlt">Tropical</span> TRopopause EXperiment (ATTREX) is a series of airborne campaigns focused on understanding physical processes in the <span class="hlt">Tropical</span> Tropopause Layer (TTL) and their role in atmospheric chemistry and climate. ATTREX is using the high-altitude, long-duration NASA Global Hawk Unmanned Air System to make in situ and remote-sensing measurements spanning the <span class="hlt">Pacific</span>. A particular ATTREX emphasis is to better understand the dehydration of air as it passes through the cold <span class="hlt">tropical</span> tropopause region. The ATTREX payload contains 12 in situ and remote sensing instruments that measure water vapor, carbon dioxide, methane, nonmethane hydrocarbons, sulfur hexafluoride, chlorofluorocarbons, nitrous oxide), reactive chemical compounds (ozone, bromine, nitrous oxide), meteorological parameters, and radiative fluxes. During January-March, 2014, the Global Hawk was deployed to Guam for ATTREX flights. Six science flights were conducted from Guam (in addition to the transits across the <span class="hlt">Pacific</span>), resulting in over 100 hours of Western <span class="hlt">Pacific</span> TTL sampling and about 180 vertical profiles through the TTL. I will provide an overview of the dataset, with examples of the measurements including meteorological parameters, clouds and water vapor, and chemical tracers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24116406','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24116406"><span>Ocean noise in the <span class="hlt">tropical</span> and subtropical <span class="hlt">Pacific</span> Ocean.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Sirović, Ana; Wiggins, Sean M; Oleson, Erin M</p> <p>2013-10-01</p> <p>Ocean ambient noise is well studied in the North <span class="hlt">Pacific</span> and North Atlantic but is poorly described for most of the worlds' oceans. Calibrated passive acoustic recordings were collected during 2009-2010 at seven locations in the <span class="hlt">central</span> and western <span class="hlt">tropical</span> and subtropical <span class="hlt">Pacific</span>. Monthly and hourly mean power spectra (15-1000 Hz) were calculated in addition to their skewness, kurtosis, and percentile distributions. Overall, ambient noise at these seven sites was 10-20 dB lower than reported recently for most other locations in the North <span class="hlt">Pacific</span>. At frequencies <100 Hz, spectrum levels were equivalent to those predicted for remote or light shipping. Noise levels in the 40 Hz band were compared to the presence of nearby and distant ships as reported to the World Meteorological Organization Voluntary Observing Ship Scheme (VOS) project. There was a positive, but nonsignificant correlation between distant shipping and low frequency noise (at 40 Hz). There was a seasonal variation in ambient noise at frequencies >200 Hz with higher levels recorded in the winter than in the summer. Several species of baleen whales, humpback (Megaptera novaeangliae), blue (Balaenoptera musculus), and fin (B. physalus) whales, also contributed seasonally to ambient noise in characteristic frequency bands.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ClDy..tmp..867D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ClDy..tmp..867D"><span>Distinct winter patterns of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> convection anomaly and the associated extratropical wave trains in the Northern Hemisphere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ding, Shuoyi; Chen, Wen; Graf, Hans-F.; Guo, Yuanyuan; Nath, Debashis</p> <p>2017-11-01</p> <p>In this paper, distinct patterns of boreal winter convection anomalies over the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> and associated wave trains in the extratropics are addressed. The first leading mode (EOF1) of convection anomalies as measured by outgoing longwave radiation demonstrates an east-west oscillation of deep convection with centers over the equatorial <span class="hlt">central</span> <span class="hlt">Pacific</span> (CP) and over the <span class="hlt">tropical</span> western North <span class="hlt">Pacific</span> and the Maritime Continent. The second leading mode (EOF2) is also a dipole pattern with opposite centers straddling 170°W, possibly modifying EOF1 to some extent. Combining the first two leading modes, five major categories of <span class="hlt">tropical</span> convection anomalies can be identified for the period 1979/80-2012/13. The comparison between these five categories and the corresponding SST anomaly patterns indicates a nonlinear relationship between convection and SST. The combination of EOF1 and EOF2 with in-phase PCs exhibits an east-west dipole pattern with opposite signs over west of the dateline and the Maritime Continent. The negative phase of the two PCs, named La Niña pattern, induces a negative <span class="hlt">Pacific</span>/North American—positive North Atlantic Oscillation teleconnection in the extratropics. Approximately opposite responses can be detected in its positive phase, named CP El Niño pattern. The negative PC2 superposing positive PC1, named EP El Niño pattern, shows the strongest convection anomalies with enhanced (depressed) convection over the eastern (western) <span class="hlt">Pacific</span> and leads to a <span class="hlt">Tropical</span>/Northern Hemisphere-like teleconnection pattern and an anomalous anticyclone extending from the North <span class="hlt">Pacific</span> to the North Atlantic. The positive PC2 with neutral PC1, named western CP pattern, shows weakly enhanced convection to the west of the dateline as a response to local SST warming around the dateline. This convection anomaly pattern, although weak, is important and excites a northeastward wave train from the <span class="hlt">tropics</span> to Greenland, resulting in surface air temperature</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMOS24B..03D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMOS24B..03D"><span>Eddy-induced Sea Surface Salinity changes in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Delcroix, T. C.; Chaigneau, A.; Soviadan, D.; Boutin, J.</p> <p>2017-12-01</p> <p>We analyse the Sea Surface Salinity (SSS) signature of westward propagating mesoscale eddies in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> by collocating 5 years (2010-2015) of SMOS (Soil Moisture and Ocean Salinity) SSS and altimetry-derived sea level anomalies. The main characteristics of mesoscale eddies are first identified in SLA maps. Composite analyses in the <span class="hlt">Central</span> and Eastern ITCZ regions then reveal regionally dependent impacts with opposite SSS anomalies for the cyclonic and anticyclonic eddies. In the <span class="hlt">Central</span> region (where we have the largest meridional SSS gradient), we found dipole-like SSS changes with maximum anomalies on the leading edge of the eddy. In the Eastern region (where we have the largest near-surface vertical salinity gradient) we found monopole-like SSS changes with maximum anomalies in the eddy centre. These dipole/monopole patterns and the rotational sense of eddies suggest the dominant role of horizontal and vertical advection in the <span class="hlt">Central</span> and Eastern ITCZ regions, respectively.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.A53D2279K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.A53D2279K"><span>Western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> multidecadal variability forced by the Atlantic multidecadal oscillation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kucharski, F.; Sun, C.; Li, J.; Jin, F. F.; Kang, I. S.; Ding, R.</p> <p>2017-12-01</p> <p>Observational analysis suggests that the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> (WTP) sea surface temperature (SST) shows predominant variability over multidecadal time scales, which is unlikely to be explained by the Interdecadal <span class="hlt">Pacific</span> Oscillation. Here we show that this variability is largely explained by the remote Atlantic multidecadal oscillation (AMO). A suite of Atlantic Pacemaker experiments successfully reproduces the WTP multidecadal variability and the AMO-WTP SST connection. The AMO warm SST anomaly generates an atmospheric teleconnection to the North <span class="hlt">Pacific</span>, which weakens the Aleutian low and subtropical North <span class="hlt">Pacific</span> westerlies. The wind changes induce a subtropical North <span class="hlt">Pacific</span> SST warming through wind-evaporation-SST effect, and in response to this warming, the surface winds converge towards the subtropical North <span class="hlt">Pacific</span> from the <span class="hlt">tropics</span>, leading to anomalous cyclonic circulation and low pressure over the WTP region. The warm SST anomaly further develops due to the SST-sea level pressure-cloud-longwave radiation positive feedback. Our findings suggest that the Atlantic Ocean acts as a key pacemaker for the western <span class="hlt">Pacific</span> decadal climate variability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5504304','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5504304"><span>Western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> multidecadal variability forced by the Atlantic multidecadal oscillation</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Sun, Cheng; Kucharski, Fred; Li, Jianping; Jin, Fei-Fei; Kang, In-Sik; Ding, Ruiqiang</p> <p>2017-01-01</p> <p>Observational analysis suggests that the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> (WTP) sea surface temperature (SST) shows predominant variability over multidecadal time scales, which is unlikely to be explained by the Interdecadal <span class="hlt">Pacific</span> Oscillation. Here we show that this variability is largely explained by the remote Atlantic multidecadal oscillation (AMO). A suite of Atlantic Pacemaker experiments successfully reproduces the WTP multidecadal variability and the AMO–WTP SST connection. The AMO warm SST anomaly generates an atmospheric teleconnection to the North <span class="hlt">Pacific</span>, which weakens the Aleutian low and subtropical North <span class="hlt">Pacific</span> westerlies. The wind changes induce a subtropical North <span class="hlt">Pacific</span> SST warming through wind–evaporation–SST effect, and in response to this warming, the surface winds converge towards the subtropical North <span class="hlt">Pacific</span> from the <span class="hlt">tropics</span>, leading to anomalous cyclonic circulation and low pressure over the WTP region. The warm SST anomaly further develops due to the SST–sea level pressure–cloud–longwave radiation positive feedback. Our findings suggest that the Atlantic Ocean acts as a key pacemaker for the western <span class="hlt">Pacific</span> decadal climate variability. PMID:28685765</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017NatCo...815998S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017NatCo...815998S"><span>Western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> multidecadal variability forced by the Atlantic multidecadal oscillation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sun, Cheng; Kucharski, Fred; Li, Jianping; Jin, Fei-Fei; Kang, In-Sik; Ding, Ruiqiang</p> <p>2017-07-01</p> <p>Observational analysis suggests that the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> (WTP) sea surface temperature (SST) shows predominant variability over multidecadal time scales, which is unlikely to be explained by the Interdecadal <span class="hlt">Pacific</span> Oscillation. Here we show that this variability is largely explained by the remote Atlantic multidecadal oscillation (AMO). A suite of Atlantic Pacemaker experiments successfully reproduces the WTP multidecadal variability and the AMO-WTP SST connection. The AMO warm SST anomaly generates an atmospheric teleconnection to the North <span class="hlt">Pacific</span>, which weakens the Aleutian low and subtropical North <span class="hlt">Pacific</span> westerlies. The wind changes induce a subtropical North <span class="hlt">Pacific</span> SST warming through wind-evaporation-SST effect, and in response to this warming, the surface winds converge towards the subtropical North <span class="hlt">Pacific</span> from the <span class="hlt">tropics</span>, leading to anomalous cyclonic circulation and low pressure over the WTP region. The warm SST anomaly further develops due to the SST-sea level pressure-cloud-longwave radiation positive feedback. Our findings suggest that the Atlantic Ocean acts as a key pacemaker for the western <span class="hlt">Pacific</span> decadal climate variability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20020039007&hterms=syed&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3DN%2Bsyed','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20020039007&hterms=syed&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3DN%2Bsyed"><span>Large-Scale Air Mass Characteristics Observed Over the Remote <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Ocean During March-April 1999: Results from PEM-<span class="hlt">Tropics</span> B Field Experiment</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Browell, Edward V.; Fenn, Marta A.; Butler, Carolyn F.; Grant, William B.; Ismail, Syed; Ferrare, Richard A.; Kooi, Susan A.; Brackett, Vincent G.; Clayton, Marian B.; Avery, Melody A.</p> <p>2001-01-01</p> <p>Eighteen long-range flights over the <span class="hlt">Pacific</span> Ocean between 38 S to 20 N and 166 E to 90 W were made by the NASA DC-8 aircraft during the NASA <span class="hlt">Pacific</span> Exploratory Mission (PEM) <span class="hlt">Tropics</span> B conducted from March 6 to April 18, 1999. Two lidar systems were flown on the DC-8 to remotely measure vertical profiles of ozone (O3), water vapor (H2O), aerosols, and clouds from near the surface to the upper troposphere along their flight track. In situ measurements of a wide range of gases and aerosols were made on the DC-8 for comprehensive characterization of the air and for correlation with the lidar remote measurements. The transition from northeasterly flow of Northern Hemispheric (NH) air on the northern side of the Intertropical Convergence Zone (ITCZ) to generally easterly flow of Southern Hemispheric (SH) air south of the ITCZ was accompanied by a significant decrease in O3, carbon monoxide, hydrocarbons, and aerosols and an increase in H2O. Trajectory analyses indicate that air north of the ITCZ came from Asia and/or the United States, while the air south of the ITCZ had a long residence time over the <span class="hlt">Pacific</span>, perhaps originating over South America several weeks earlier. Air south of the South <span class="hlt">Pacific</span> Convergence Zone (SPCZ) came rapidly from the west originating over Australia or Africa. This air had enhanced O3 and aerosols and an associated decrease in H2O. Average latitudinal and longitudinal distributions of O3 and H2O were constructed from the remote and in situ O3 and H2O data, and these distributions are compared with results from PEM-<span class="hlt">Tropics</span> A conducted in August-October 1996. During PEM-<span class="hlt">Tropics</span> B, low O3 air was found in the SH across the entire <span class="hlt">Pacific</span> Basin at low latitudes. This was in strong contrast to the photochemically enhanced O3 levels found across the <span class="hlt">central</span> and eastern <span class="hlt">Pacific</span> low latitudes during PEM-<span class="hlt">Tropics</span> A. Nine air mass types were identified for PEM-<span class="hlt">Tropics</span> B based on their O3, aerosols, clouds, and potential vorticity characteristics. The</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008DSRI...55..587T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008DSRI...55..587T"><span>Summer circulation in the Mexican <span class="hlt">tropical</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Trasviña, A.; Barton, E. D.</p> <p>2008-05-01</p> <p>The main components of large-scale circulation of the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> were identified in the mid 20th century, but the details of the circulation at length scales of 10 2 km or less, the mesoscale field, are less well known particularly during summer. The winter circulation is characterized by large mesoscale eddies generated by intense cross-shore wind pulses. These eddies propagate offshore to provide an important source of mesoscale variability for the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. The summer circulation has not commanded similar attention, the main reason being that the frequent generation of hurricanes in the area renders in situ observations difficult. Before the experiment presented here, the large-scale summer circulation of the Gulf of Tehuantepec was thought to be dominated by a poleward flow along the coast. A drifter-deployment experiment carried out in June 2000, supported by satellite altimetry and wind data, was designed to characterize this hypothesized Costa Rica Coastal Current. We present a detailed comparison between altimetry-estimated geostrophic and in situ currents estimated from drifters. Contrary to expectation, no evidence of a coherent poleward coastal flow across the gulf was found. During the 10-week period of observations, we documented a recurrent pattern of circulation within 500 km of shore, forced by a combination of local winds and the regional-scale flow. Instead of the Costa Rica Coastal Current, we found a summer eddy field capable of influencing large areas of the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. Even in summer, the cross-isthmus wind jet is capable of inducing eddy formation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMPP31A1271W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMPP31A1271W"><span>Last Millennium ENSO-Mean State Interactions in the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wyman, D. A.; Conroy, J. L.; Karamperidou, C.</p> <p>2017-12-01</p> <p>The nature and degree of interaction between the mean state of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> and ENSO remains an open question. Here we use high temporal resolution, <span class="hlt">tropical</span> <span class="hlt">Pacific</span> sea surface temperature (SST) records from the last millennium to investigate the relationship between ENSO and the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> zonal sea surface temperature gradient (hereafter dSST). A dSST time series was created by standardizing, interpolating, and compositing 7 SST records from the western and 3 SST records from the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. Propagating the age uncertainty of each of these records was accomplished through a Monte Carlo Empirical Orthogonal Function analysis. We find last millennium dSST is strong from 700 to 1300 CE, begins to weaken at approximately 1300 CE, and decreases more rapidly at 1700 CE. dSST was compared to 14 different ENSO reconstructions, independent of the records used to create dSST, to assess the nature of the ENSO-mean state relationship. dSST correlations with 50-year standard deviations of ENSO reconstructions are consistently negative, suggesting that more frequent, strong El Niño events on this timescale reduces dSST. To further assess the strength and direction of the ENSO-dSST relationship, moving 100-year standard deviations of ENSO reconstructions were compared to moving 100-year averages of dSST using Cohen's Kappa statistic, which measures categorical agreement. The Li et al. (2011) and Li et al. (2013) Nino 3.4 ENSO reconstructions had the highest agreement with dSST (k=0.80 and 0.70, respectively), with greater ENSO standard deviation coincident with periods of weak dSST. Other ENSO reconstructions showed weaker agreement with dSST, which may be partly due to low sample size. The consistent directional agreement of dSST with ENSO, coupled with the inability of strong ENSO events to develop under a weak SST gradient, suggests periods of more frequent strong El Niño events reduced <span class="hlt">tropical</span> <span class="hlt">Pacific</span> dSST on centennial timescales over the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMPP33A1314A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMPP33A1314A"><span>Response of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> to abrupt climate change 8,200 years ago</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Atwood, A. R.; Battisti, D.; Bitz, C. M.; Sachs, J. P.</p> <p>2017-12-01</p> <p>The relatively stable climate of the Holocene epoch was punctuated by a period of large and abrupt climate change ca. 8,200 yr BP, when an outburst of glacial meltwater into the Labrador Sea drove large and abrupt climate changes across the globe. However, little is known about the response of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> to this event. We present the first evidence for large perturbations to the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> climate, based on sedimentary biomarker and hydrogen isotopic records from a freshwater lake in the Galápagos Islands. We inform these reconstructions with freshwater forcing simulations performed with the Community Climate System Model version 4. Together, the biomarker records and model simulations provide evidence for a mechanistic link between (1) a southward shift of the Intertropical Convergence Zone in the eastern equatorial <span class="hlt">Pacific</span> and (2) decreased frequency and/or intensity of Eastern <span class="hlt">Pacific</span> El Niño events during the 8,200 BP event. While climate theory and modeling studies support a southward shift of the ITCZ in response to a weakened AMOC, the dynamical drivers for the observed change in ENSO variability are less well developed. To explore these linkages, we perform simulations with an intermediate complexity model of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. These results provide valuable insight into the controls of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> climate variability and the mechanisms behind the global response to abrupt climate change.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.prh.noaa.gov/cphc/pages/TWO.php','SCIGOVWS'); return false;" href="http://www.prh.noaa.gov/cphc/pages/TWO.php"><span><span class="hlt">Central</span> <span class="hlt">Pacific</span> Hurricane Center - Honolulu, Hawai`i</span></a></p> <p><a target="_blank" href="http://www.science.gov/aboutsearch.html">Science.gov Websites</a></p> <p></p> <p></p> <p>Department of Commerce <span class="hlt">Central</span> <span class="hlt">Pacific</span> <em>Hurricane</em> Center National Oceanic and Atmospheric Administration Blank Tracking Maps â¾ Educational Resources Be Prepared! NWS <em>Hurricane</em> Prep Week Preparedness Weather <span class="hlt">Central</span> <span class="hlt">Pacific</span> <em>Hurricane</em> Center Honolulu HI 800 PM HST Thu Nov 30 2017 For the <span class="hlt">central</span> North <span class="hlt">Pacific</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.3421W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.3421W"><span>Interdecadal Change in the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Precipitation Anomaly Pattern around the Late 1990s during Boreal Spring</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wen, Zhiping; Guo, Yuanyuan; Wu, Renguang</p> <p>2017-04-01</p> <p>The leading mode of boreal spring precipitation variability over the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> experienced a pronounced interdecadal change around the late 1990s. The pattern before 1998 features positive precipitation anomalies over the equatorial eastern <span class="hlt">Pacific</span> (EP) with positive principle component years. The counterpart after 1998 exhibits a westward shift of the positive center to the equatorial <span class="hlt">central</span> <span class="hlt">Pacific</span> (CP). Observational evidence shows that this interdecadal change in the leading mode of precipitation variability is closely associated with a distinctive sea surface temperature (SST) anomaly pattern. The westward shift of the anomalous precipitation center after 1998 is in tandem with a similar shift of maximum warming from the EP to CP. Diagnostic analyses based on a linear equation of the mixed layer temperature anomaly exhibit that an interdecadal enhancement of zonal advection (ZA) feedback process plays a vital role in the shift in the leading mode of both the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> SST and the precipitation anomaly during spring. Moreover, the variability of the anomalous zonal current at the upper ocean dominates the ZA feedback change, while the mean zonal SST gradient associated with a La Niña-like pattern of the mean state only accounts for a relatively trivial proportion of the ZA feedback change. It was found that both the relatively rapid decaying of the SST anomalies in the EP and the La Niña-like mean state make it conceivable that the shift of the leading mode of the <span class="hlt">tropical</span> precipitation anomaly only occurs in spring. In addition, the largest variance of the anomalous zonal current in spring might contribute to the unique interdecadal change in the <span class="hlt">tropical</span> spring precipitation anomaly pattern.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li class="active"><span>4</span></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_4 --> <div id="page_5" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li class="active"><span>5</span></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="81"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1998JCli...11..551B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1998JCli...11..551B"><span>The Relationships between <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> and Atlantic SST and Northeast Brazil Monthly Precipitation.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bertacchi Uvo, Cintia; Repelli, Carlos A.; Zebiak, Stephen E.; Kushnir, Yochanan</p> <p>1998-04-01</p> <p>The monthly patterns of northeast Brazil (NEB) precipitation are analyzed in relation to sea surface temperature (SST) in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> and Atlantic Oceans, using singular value decomposition. It is found that the relationships between precipitation and SST in both basins vary considerably throughout the rainy season (February-May). In January, equatorial <span class="hlt">Pacific</span> SST is weakly correlated with precipitation in small areas of southern NEB, but Atlantic SST shows no significant correlation with regional precipitation. In February, <span class="hlt">Pacific</span> SST is not well related to precipitation, but south equatorial Atlantic SST is positively correlated with precipitation over the northern Nordeste, the latter most likely reflecting an anomalously early (or late) southward migration of the ITCZ precipitation zone. During March, equatorial <span class="hlt">Pacific</span> SST is negatively correlated with Nordeste precipitation, but no consistent relationship between precipitation and Atlantic SST is found. Atlantic SST-precipitation correlations for April and May are the strongest found among all months or either ocean. Precipitation in the Nordeste is positively correlated with SST in the south <span class="hlt">tropical</span> Atlantic and negatively correlated with SST in the north <span class="hlt">tropical</span> Atlantic. These relationships are strong enough to determine the structure of the seasonal mean SST-precipitation correlations, even though the corresponding patterns for the earlier months of the season are quite different. <span class="hlt">Pacific</span> SST-precipitation correlations for April and May are similar to those for March. Extreme wet (dry) years for the Nordeste occur when both <span class="hlt">Pacific</span> and Atlantic SST patterns for April and May occur simultaneously. A separate analysis reinforces previous findings in showing that SST in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> and the northern <span class="hlt">tropical</span> Atlantic are positively correlated and that <span class="hlt">tropical</span> <span class="hlt">Pacific</span>-south Atlantic correlations are negligible.Time-lagged analyses show the potential for forecasting either seasonal mean</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19900033070&hterms=war&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dwar','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19900033070&hterms=war&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dwar"><span>Post World War II trends in <span class="hlt">tropical</span> <span class="hlt">Pacific</span> surface trades</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Harrison, D. E.</p> <p>1989-01-01</p> <p>Multidecadal time series of surface winds from <span class="hlt">central</span> <span class="hlt">tropical</span> <span class="hlt">Pacific</span> islands are used to compute trends in the trade winds between the end of WWII and 1985. Over this period, averaged over the whole region, there is no statistically significant trend in speed or zonal or meridional wind (or pseudostress). However, there is some tendency, within a few degrees of the equator, toward weakening of the easterlies and increased meridional flow toward the equator. Anomalous conditions subsequent to the 1972-73 ENSO event make a considerable contribution to the long-term trends. The period 1974-80 has been noted previously to have been anomalous, and trends over that period are sharply greater than those over the longer records.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.A21B0024K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.A21B0024K"><span><span class="hlt">Tropical</span> <span class="hlt">Pacific</span> variability as a key pacemaker of the global warming staircase</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kosaka, Y.; Xie, S. P.</p> <p>2016-12-01</p> <p>Global-mean surface temperature (GMST) has increased since the 19th century with notable interdecadal accelerations and slowdowns, forming the global-warming "staircase". The last step of this staircase is the surface warming slowdown since the late 1990s, for which the transition of the Interdecadal <span class="hlt">Pacific</span> Oscillation (IPO) from a positive to negative state has been suggested as the leading mechanism. To examine the role of IPO in the entire warming staircase, a long pacemaker experiment is performed with a coupled climate model where <span class="hlt">tropical</span> <span class="hlt">Pacific</span> sea surface temperatures are forced to follow the observed evolution since the late 19th century. The pacemaker experiment successfully reproduces the staircase-like global warming remarkably well since 1900. Without the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> effect, the same model produces a continual warming from the 1900s to the 1960 followed by rapid warming. The successful reproduction identifies the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> decadal variability as a key pacemaker of the GMST staircase. We further propose a method to remove internal variability from observed GMST changes for real-time monitoring of anthropogenic warming.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19910044784&hterms=hierarchy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dhierarchy','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19910044784&hterms=hierarchy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dhierarchy"><span>Observations of cloud cluster hierarchies over the <span class="hlt">tropical</span> western <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lau, K. M.; Nakazawa, T.; Sui, C. H.</p> <p>1991-01-01</p> <p>The structure and propagation of <span class="hlt">tropical</span>-cloud clusters are investigated during two contrasting periods over the <span class="hlt">tropical</span> western <span class="hlt">Pacific</span> in order to determine possible similarities or differences and to compare with previous studies. Three fundamental periodicities are found in <span class="hlt">tropical</span> convection in the region: 1 day, 2-3 days, and 10-15 days. It is noted that the 10-15-day time scale is closely related to the intraseasonal oscillations propagating from the Indian Ocean to the western <span class="hlt">Pacific</span>. Large convective complexes, supercloud clusters (SSC) are found to organize in this time scale. The SCC is made up from several cloud clusters generated at 2-3-day intervals. The diurnal variation is found to be most pronounced over the maritime continent, and the amplitude of the diurnal cycle is shown to be modulated by the 2-3-day and 10-15-day oscillations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AGUFMOS53C..03X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AGUFMOS53C..03X"><span>How do American mountains affect <span class="hlt">tropical</span> <span class="hlt">Pacific</span> climate?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xie, S.; Okajima, H.; Xu, H.; Small, J.</p> <p>2006-12-01</p> <p>Mountains on the American continents affect <span class="hlt">Pacific</span> climate significantly. The gap winds across <span class="hlt">Central</span> America are a good example, imprinting on the eastern <span class="hlt">Pacific</span> intertropical convergence zone (ITCZ). The wind curls associated these gap winds maintain a thermocline dome, cooling sea surface temperature and punching a hole in the summer ITCZ west of <span class="hlt">Central</span> America. In winter, on the other hand, the eastern <span class="hlt">Pacific</span> ITCZ is known to be displaced south of the eastern <span class="hlt">Pacific</span> warm pool, almost the only exception of an otherwise close collocation of the SST maximum and ITCZ over the eastern <span class="hlt">Pacific</span>. Our regional model experiments show that as the northeast trades blow across <span class="hlt">Central</span> American mountains, the subsidence on the lee side is the cause of the southward displacement of the <span class="hlt">Pacific</span> ITCZ. A new finding from recent satellite scatterometer observations is that the gap winds, strongest in winter, displays a secondary maximum in July- August. Our diagnostic and model studies show that this summer gap wind is associated with the mid- summer draught over <span class="hlt">Central</span> America, due to the unsynchronized seasonal march between the <span class="hlt">Pacific</span> and Atlantic ITCZs. The influence of American mountains is not limited to the vicinity of the continents but spreads over the entire <span class="hlt">Pacific</span> basin. To assess this basin-scale influence, we remove these mountains in a global coupled general circulation model. The removal of American mountains weakens the latitudinal asymmetry of <span class="hlt">Pacific</span> climate, with the ITCZ staying longer south of the equator during February-May. Two orographic effects contribute to this basin-scale change in climate: a) the winter northeast trades intensify without the <span class="hlt">Central</span> American mountain barrier, which cools the SST north of the equator; b) the moisture over the Amazonia spreads to the Southeast <span class="hlt">Pacific</span> without the Andes, in favor of a southern ITCZ. In a coupled system, both effects would help move the ITCZ south of the equator during boreal spring. This change</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMOS52B..01E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMOS52B..01E"><span>Four centuries of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> sea-surface temperature from coral archives</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Emile-Geay, J.; Guillot, D.; Cobb, K. M.; Cole, J. E.; Correge, T.; Tudhope, A. W.; Rajaratnam, B.</p> <p>2012-12-01</p> <p>Our ability to judge the significance of recent climate change is fundamentally limited by the shortness and sparsity of the instrumental record. It is therefore crucial to extend the latter, particularly in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> where powerful air/sea interactions orchestrate global-scale low-frequency climate variability. Reconstructions of <span class="hlt">tropical</span> sea-surface temperature (SST) variability have traditionally relied heavily on extratropical proxy records, particularly dendrochronological ones. Such dependence hinders a rigorous examination of the links between <span class="hlt">tropical</span> SST and continental hydroclimate in the pre-instrumental era. Here we use an expanded network of high-resolution coral proxies and a novel statistical methodology (GraphEM Guillot et al., in revision) to reconstruct <span class="hlt">tropical</span> <span class="hlt">Pacific</span> SST back to 1600 C.E solely from annually-banded coral archives. The network and method prove able to capture ˜ 30% of interannual SST variability in the NINO3.4 region, but systematically under-represents El Nino events, especially strong ones, which negatively affect coral physiology at some sites. La Nina events, however, are more faithfully captured. The reconstructed NINO3.4 displays no long-term trend since 1600 C.E, contradicting claims that the twentieth century is anomalous with respect to a long-term baseline (McGregor et al., 2010). Changes in the preponderance of ENSO 'flavors' (Eastern <span class="hlt">Pacific</span> vs <span class="hlt">Central</span> <span class="hlt">Pacific</span> El Nino events) are assessed using the methodology of (Yeh et al., 2009), and suggests that the late twentieth century trend towards increased CP El Nino occurrences is within historic norms, consistent with results employing a multivariate red noise model (Newman et al., 2011). The link to North American droughts is assessed by comparison to the Palmer Drought Severity Index from the North American Drought Atlas v2a (Cook et al., 2004; Cook, 2008): the pattern corresponding to notable droughts in the US southwest is cool <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, both</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950052579&hterms=Nitrate+water&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DNitrate%2Bwater','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950052579&hterms=Nitrate+water&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DNitrate%2Bwater"><span>New production in the warm waters of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Pena, M. Angelica; Lewis, Marlon R.; Cullen, John J.</p> <p>1994-01-01</p> <p>The average depth-integrated rate of new production in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean was estimated from a calculation of horizontal and vertical nitrate balance over the region enclosed by the climatological 26 C isotherm. The net turbulent flux of nitrate into the region was computed in terms of the climatological net surface heat flux and the nitrate-temperature relationship at the base of the 26 C isotherm. The net advective transport of nitrate into the region was estimated using the mean nitrate distribution obtained from the analysis of historical data and previous results of a general circulation model of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. The rate of new production resulting from vertical turbulent fluxes of nitrate was found to be similar in magnitude to that due to advective transport. Most (about 75%) of the advective input of nitrate was due to the horizontal transport of nutrient-rich water from the eastern equatorial region rather than from equatorial upwelling. An average rate of new production of 14.5 - 16 g C/sq m/yr was found for the warm waters of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> region. These values are in good agreement with previous estimates for this region and are almost five times less than is estimated for the eastern equatorial <span class="hlt">Pacific</span>, where most of the nutrient upwelling occurs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018AdAtS..35..682W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018AdAtS..35..682W"><span>Impact of the Spring SST Gradient between the <span class="hlt">Tropical</span> Indian Ocean and Western <span class="hlt">Pacific</span> on Landfalling <span class="hlt">Tropical</span> Cyclone Frequency in China</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Lei; Chen, Guanghua</p> <p>2018-06-01</p> <p>The present study identifies a significant influence of the sea surface temperature gradient (SSTG) between the <span class="hlt">tropical</span> Indian Ocean (TIO; 15°S-15°N, 40°-90°E) and the western <span class="hlt">Pacific</span> warm pool (WWP; 0°-15°N, 125°-155°E) in boreal spring on <span class="hlt">tropical</span> cyclone (TC) landfall frequency in mainland China in boreal summer. During the period 1979-2015, a positive spring SSTG induces a zonal inter-basin circulation anomaly with lower-level convergence, mid-tropospheric ascendance and upper-level divergence over the west-<span class="hlt">central</span> TIO, and the opposite situation over the WWP, which produces lower-level anomalous easterlies and upper-level anomalous westerlies between the TIO and WWP. This zonal circulation anomaly further warms the west-<span class="hlt">central</span> TIO by driving warm water westward and cools the WWP by inducing local upwelling, which facilitates the persistence of the anomaly until the summer. Consequently, lower-level negative vorticity, strong vertical wind shear and lower-level anticyclonic anomalies prevail over most of the western North <span class="hlt">Pacific</span> (WNP), which decreases the TC genesis frequency. Meanwhile, there is an anomalous mid-tropospheric anticyclone over the main WNP TC genesis region, meaning a westerly anomaly dominates over coastal regions of mainland China, which is unfavorable for steering TCs to make landfall in mainland China during summer. This implies that the spring SSTG may act as a potential indicator for TC landfall frequency in mainland China.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ClDy..tmp.2363Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ClDy..tmp.2363Y"><span>Understanding the effect of an excessive cold tongue bias on projecting the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> SST warming pattern in CMIP5 models</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ying, Jun; Huang, Ping; Lian, Tao; Tan, Hongjian</p> <p>2018-05-01</p> <p>An excessive cold tongue is a common bias among current climate models, and considered an important source of bias in projections of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> climate change under global warming. Specifically, the excessive cold tongue bias is closely related to the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> SST warming (TPSW) pattern. In this study, we reveal that two processes are the critical mechanisms by which the excessive cold tongue bias influences the projection of the TPSW pattern, based on 32 models from phase 5 of Coupled Model Intercomparison Projection (CMIP5). On the one hand, by assuming that the shortwave (SW) radiation to SST feedback is linearly correlated to the cold tongue SST, the excessive cold tongue bias can induce an overly weak negative SW-SST feedback in the <span class="hlt">central</span> <span class="hlt">Pacific</span>, which can lead to a positive SST warming bias in the <span class="hlt">central</span> to western <span class="hlt">Pacific</span> (around 150°E-140°W). Moreover, the overly weak local atmospheric dynamics response to SST is a key process of the overly weak SW-SST feedback, compared with the cloud response to atmospheric dynamics and the SW radiation response to cloud. On the other hand, the overly strong ocean zonal overturning circulation associated with the excessive cold tongue bias results in an overestimation of the ocean dynamical thermostat effect, with enhanced ocean stratification under global warming, leading to a negative SST warming bias in the <span class="hlt">central</span> and eastern <span class="hlt">Pacific</span> (around 170°W-120°W). These two processes jointly form a positive SST warming bias in the western <span class="hlt">Pacific</span>, contributing to a La Niña-like warming bias. Therefore, we suggest a more realistic climatological cold tongue SST is needed for a more reliable projection of the TPSW pattern.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018BGeo...15.2619K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018BGeo...15.2619K"><span>Distribution and rates of nitrogen fixation in the western <span class="hlt">tropical</span> South <span class="hlt">Pacific</span> Ocean constrained by nitrogen isotope budgets</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Knapp, Angela N.; McCabe, Kelly M.; Grosso, Olivier; Leblond, Nathalie; Moutin, Thierry; Bonnet, Sophie</p> <p>2018-05-01</p> <p>Constraining the rates and spatial distribution of dinitrogen (N2) fixation fluxes to the ocean informs our understanding of the environmental sensitivities of N2 fixation as well as the timescale over which the fluxes of nitrogen (N) to and from the ocean may respond to each other. Here we quantify rates of N2 fixation as well as its contribution to export production along a zonal transect in the western <span class="hlt">tropical</span> South <span class="hlt">Pacific</span> (WTSP) Ocean using N isotope (<q>δ15N</q>) budgets. Comparing measurements of water column nitrate + nitrite δ15N with the δ15N of sinking particulate N at a western, <span class="hlt">central</span>, and eastern station, these δ15N budgets indicate high, modest, and low rates of N2 fixation at the respective stations. The results also imply that N2 fixation supports exceptionally high, i.e. ≥ 50 %, of export production at the western and <span class="hlt">central</span> stations, which are also proximal to the largest iron sources. These geochemically based rates of N2 fixation are equal to or greater than those previously reported in the <span class="hlt">tropical</span> North Atlantic, indicating that the WTSP Ocean has the capacity to support globally significant rates of N2 fixation, which may compensate for N removal in the oxygen-deficient zones of the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JOL....36...20Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JOL....36...20Z"><span>Impacts of SST anomalies in the Indian-<span class="hlt">Pacific</span> basin on Northwest <span class="hlt">Pacific</span> <span class="hlt">tropical</span> cyclone activities during three super El Niño years</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhan, Ruifen; Chen, Baode; Ding, Yihui</p> <p>2018-01-01</p> <p>This study investigated the impact of sea surface temperature (SST) in several important areas of the Indian-<span class="hlt">Pacific</span> basin on <span class="hlt">tropical</span> cyclone (TC) activity over the western North <span class="hlt">Pacific</span> (WNP) during the developing years of three super El Niño events (1982, 1997, and 2015) based on observations and numerical simulations. During the super El Niño years, TC intensity was enhanced considerably, TC days increased, TC tracks mostly recurved along the coasts, and fewer TCs made landfall in China. These characteristics are similar to the strong ENSO-TC relationship but further above the climatological means than in strong El Niño years. It indicates that super El Niño events play a dominant role in the intensities and tracks of WNP TCs. However, there were clear differences in both numbers and positions of TC genesis among the different super El Niño years. These features could be attributed to the collective impact of SST anomalies (SSTAs) in the <span class="hlt">tropical</span> <span class="hlt">central</span>-eastern <span class="hlt">Pacific</span> and East Indian Ocean (EIO) and the SST gradient (SSTG) between the southwestern <span class="hlt">Pacific</span> and the western <span class="hlt">Pacific</span> warm pool. During 2015, the EIO SSTA was extremely warm and the anomalous anticyclone in the western WNP was enhanced, resulting in fewer TCs than normal. In 1982, the EIO SSTA and spring SSTG showed negative anomalies, followed by an increased anomalous cyclone in the western WNP and equatorial vertical wind shear. This intensified the conversion of eddy kinetic energy from large-scale flows, favorable for the westward shift of TC genesis. Consequently, anomalous TC activities during the super El Niño years resulted mainly from combined SSTA impacts of different key areas over the Indian-<span class="hlt">Pacific</span> basin.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA620426','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA620426"><span><span class="hlt">Tropical</span> Cyclone Reconnaissance with the Global Hawk: Operational Thresholds and Characteristics of Convective Systems Over the <span class="hlt">Tropical</span> Western North <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2013-12-01</p> <p><span class="hlt">Tropical</span> cyclone research is an intense ongoing science that has acquired even greater importance in this era of global climate change . Increased study of...RECONNAISSANCE WITH THE GLOBAL HAWK: OPERATIONAL THRESHOLDS AND CHARACTERISTICS OF CONVECTIVE SYSTEMS OVER THE <span class="hlt">TROPICAL</span> WESTERN NORTH <span class="hlt">PACIFIC</span> by...<span class="hlt">TROPICAL</span> CYCLONE RECONNAISSANCE WITH THE GLOBAL HAWK: OPERATIONAL THRESHOLDS AND CHARACTERISTICS OF CONVECTIVE SYSTEMS OVER THE <span class="hlt">TROPICAL</span> WESTERN</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1995GeoRL..22.2581A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1995GeoRL..22.2581A"><span>Control of <span class="hlt">tropical</span> instability waves in the <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Allen, M. R.; Lawrence, S. P.; Murray, M. J.; Mutlow, C. T.; Stockdale, T. N.; Llewellyn-Jones, D. T.; Anderson, D. L. T.</p> <p></p> <p>Westward-propagating waves with periods of 20-30 days and wavelengths of ˜ 1,100km are a prominent feature of sea-surface temperatures (SSTs) in the equatorial <span class="hlt">Pacific</span> and Atlantic Oceans. They have been attributed to instabilities due to current shear. We compare SST observations from the spaceborne Along Track Scanning Radiometer (ATSR) and TOGA-TAO moored buoys with SSTs from a model of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> forced with observed daily windstress data. The phases of the strongest “<span class="hlt">Tropical</span> Instability Waves” (TIWs) in the model are in closer correspondence with those observed than we would expect if these waves simply developed from infinitesimal disturbances (in which case their phases would be arbitrary). If we filter out the intraseasonal component of the windstress, all phase-correspondence is lost. We conclude that the phases of these waves are not arbitrary, but partially determined by the intraseasonal winds. The subsurface evolution of the model suggests a possible control mechanism is through interaction with remotely-forced subsurface Kelvin and Rossby waves. This is supported by an experiment which shows how zonal wind bursts in the west <span class="hlt">Pacific</span> can modify the TIW field, but other mechanisms, such as local feedbacks, are also possible.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ASCMO...2..155D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ASCMO...2..155D"><span>Analysis of variability of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> sea surface temperatures</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Davies, Georgina; Cressie, Noel</p> <p>2016-11-01</p> <p>Sea surface temperature (SST) in the <span class="hlt">Pacific</span> Ocean is a key component of many global climate models and the El Niño-Southern Oscillation (ENSO) phenomenon. We shall analyse SST for the period November 1981-December 2014. To study the temporal variability of the ENSO phenomenon, we have selected a subregion of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean, namely the Niño 3.4 region, as it is thought to be the area where SST anomalies indicate most clearly ENSO's influence on the global atmosphere. SST anomalies, obtained by subtracting the appropriate monthly averages from the data, are the focus of the majority of previous analyses of the <span class="hlt">Pacific</span> and other oceans' SSTs. Preliminary data analysis showed that not only Niño 3.4 spatial means but also Niño 3.4 spatial variances varied with month of the year. In this article, we conduct an analysis of the raw SST data and introduce diagnostic plots (here, plots of variability vs. <span class="hlt">central</span> tendency). These plots show strong negative dependence between the spatial standard deviation and the spatial mean. Outliers are present, so we consider robust regression to obtain intercept and slope estimates for the 12 individual months and for all-months-combined. Based on this mean-standard deviation relationship, we define a variance-stabilizing transformation. On the transformed scale, we describe the Niño 3.4 SST time series with a statistical model that is linear, heteroskedastic, and dynamical.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ClDy...49.3647X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ClDy...49.3647X"><span>A real-time ocean reanalyses intercomparison project in the context of <span class="hlt">tropical</span> <span class="hlt">pacific</span> observing system and ENSO monitoring</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xue, Yan; Wen, C.; Kumar, A.; Balmaseda, M.; Fujii, Y.; Alves, O.; Martin, M.; Yang, X.; Vernieres, G.; Desportes, C.; Lee, T.; Ascione, I.; Gudgel, R.; Ishikawa, I.</p> <p>2017-12-01</p> <p>An ensemble of nine operational ocean reanalyses (ORAs) is now routinely collected, and is used to monitor the consistency across the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> temperature analyses in real-time in support of ENSO monitoring, diagnostics, and prediction. The ensemble approach allows a more reliable estimate of the signal as well as an estimation of the noise among analyses. The real-time estimation of signal-to-noise ratio assists the prediction of ENSO. The ensemble approach also enables us to estimate the impact of the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Observing System (TPOS) on the estimation of ENSO-related oceanic indicators. The ensemble mean is shown to have a better accuracy than individual ORAs, suggesting the ensemble approach is an effective tool to reduce uncertainties in temperature analysis for ENSO. The ensemble spread, as a measure of uncertainties in ORAs, is shown to be partially linked to the data counts of in situ observations. Despite the constraints by TPOS data, uncertainties in ORAs are still large in the northwestern <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, in the SPCZ region, as well as in the <span class="hlt">central</span> and northeastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. The uncertainties in total temperature reduced significantly in 2015 due to the recovery of the TAO/TRITON array to approach the value before the TAO crisis in 2012. However, the uncertainties in anomalous temperature remained much higher than the pre-2012 value, probably due to uncertainties in the reference climatology. This highlights the importance of the long-term stability of the observing system for anomaly monitoring. The current data assimilation systems tend to constrain the solution very locally near the buoy sites, potentially damaging the larger-scale dynamical consistency. So there is an urgent need to improve data assimilation systems so that they can optimize the observation information from TPOS and contribute to improved ENSO prediction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMOS43C..05M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMOS43C..05M"><span>Complexity of <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Ecosystem and Biogeochemistry: Diurnal to Decadal, Plankters to Penguins</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Murtugudde, R. G.; Wang, X.; Valsala, V.; Karnauskas, K. B.</p> <p>2016-12-01</p> <p><span class="hlt">Tropical</span> <span class="hlt">Pacific</span> spans nearly 50% of the global <span class="hlt">tropics</span> allowing to have its own mind in terms of climate variability and physical-biogeochemical interactions. While the El Niño-Southern Oscillation (ENSO) and its flavors get much attention, it is fairly clear by now that any further improvements in ENSO prediction skills and reliability of global warming projections must begin to observe and represent bio-physical interactions in the climate and Earth System models. Coupled climate variability over the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> has a global reach with its diurnal to decadal timescales being manifest in ecosystem and biogechemistry. Zonal and meridional contrasts in biogeochemistry across the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> is closely related to seasonal variability, ENSO diversity and the PDO. Apparent dominance of ocean dynamic controls on biogeochemistry belies the potential biogeochemical feedbacks on ocean dynamics which may well explain some of the chronic biases in the state-of-the-art climate models. The east <span class="hlt">Pacific</span> cold-tongue is the most productive open ocean region in the world and home to a unique physical-biogeochmical laboratory, viz., the Galapagos. The Galapagos islands not only control the coupled climate variability via their ability to terminate the equatorial undercurrent but also offer a clear example of a biological loophole in terms of their impact on local upwelling and an expanding penguin habitat in the face of global warming. The complex bio-physical interactions in the cold-tongue and their influence on climate predictions and projections require a holisti thinking on future observing systems. <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> offers a natural laboratory for designing a robust and sustained physical-biogeochemical observation system that can effectively bridge climate predictions and projections into a unified framework for subseasonal to multidecadal timescales. Such a system will be a foundation for establishing similar systems over the rest of the World ocean to seemlessly</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ClDy..tmp.2423D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ClDy..tmp.2423D"><span>Patterns of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> convection anomalies and associated extratropical wave trains in AMIP5</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ding, Shuoyi; Chen, Wen; Graf, Hans-F.; Guo, Yuanyuan</p> <p>2018-05-01</p> <p>In this paper, the performance of 18 Coupled Model Intercomparison Project Phase 5 (CMIP5) models forced by observational SSTs in simulating the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> convective variation and the atmospheric responses in the extratropics are assessed. The multi-model ensemble mean results of 18 CMIP5 models show that five major patterns of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> convection anomaly in winter can indeed be well reproduced, however, the simulation of the corresponding extratropical responses for each pattern exists some deficiency except for the La Niña pattern compared with observations. We defined an optimized subset of well performing models (ACCESS1.0, CanAM4, CCSM4, CMCC-CM, HadGEM2-A, MPI-ESM-MR) in <span class="hlt">tropical</span> <span class="hlt">Pacific</span> deep convection according to the ranking of model skill score. These models exhibit approximately identical convection anomaly patterns in both amplitude and spatial structure to the observation, which potentially might improve the representation of extratropical teleconnections with the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, especially for the CP El Niño (CPEN), EP El Niño (EPEN) and western CP (W-CP) patterns. Both evident atmospheric anomalies of CPEN and EPEN patterns over the NA/E sector and the northeastward propagating wave trains of W-CP pattern can be quite well simulated in the high-skilled models.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMPP53B1131T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMPP53B1131T"><span>Spatial δ18Osw-SSS relationship across the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Thompson, D. M.; Conroy, J. L.; Wyman, A.; Read, D.</p> <p>2017-12-01</p> <p>Dynamic hydroclimate processes across the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> lead to strong spatial and temporal variability in δ18Osw and sea-surface salinity (SSS) across the western <span class="hlt">Pacific</span>. Corals in this region have therefore provided key information about past SSS variability, as δ18Osw contributes strongly to coral δ18O across this region. However, uncertainties in the δ18Osw-SSS relationship across space and time often limit quantitative SSS reconstructions from such coral records. Recent work demonstrates considerable variability in the δ18Osw-SSS relationship across the <span class="hlt">Pacific</span>, which may lead to over- or under-estimation of the contribution of SSS to coral δ18O, particularly across the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> (Conroy et al. 2017). Here we assess the spatial δ18Osw-SSS relationship across the dynamic western <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, capitalizing on a transit between Subic Bay, Philippines and Townsville, Australia aboard the International Ocean Discovery program's JOIDES Resolution. Water samples and weather conditions were collected 3 times daily (6:00, 12:00, 18:00) en route, resulting in a network of 47 samples spaced at semi-regular 130-260 km intervals across the western <span class="hlt">Pacific</span> from 14°N to 18°S. The route also crossed near long-term δ18Osw monitoring sites at Papua New Guinea and Palau (Conroy et al. 2017), allowing us to compare the spatial and temporal δ18Osw-SSS relationships at these sites and test the space-for-time assumption. We present the δ18Osw-SSS relationship across this region, compare the relationship across space and time, and discuss the implications of our results for SSS reconstructions from coral δ18O.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://images.nasa.gov/#/details-GSFC_20171208_Archive_e000272.html','SCIGOVIMAGE-NASA'); return false;" href="https://images.nasa.gov/#/details-GSFC_20171208_Archive_e000272.html"><span>NASA Sees Hurricane Celia Headed for <span class="hlt">Central</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="https://images.nasa.gov/">NASA Image and Video Library</a></p> <p></p> <p>2017-12-08</p> <p>Hurricane Celia is currently in the Eastern <span class="hlt">Pacific</span> Ocean, but once it passes west of 140 degrees west longitude, warnings on the system will be issued by NOAA's <span class="hlt">Central</span> <span class="hlt">Pacific</span> Hurricane Center. On July 11 at 22:05 UTC (6:05 p.m. EDT) the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard NASA-NOAA-DOD's Suomi NPP satellite captured a visible light image of Hurricane Celia that showed a cloud-filled eye with powerful bands of thunderstorms wrapping around the low level center. The VIIRS image also showed a large band of thunderstorms that extended to the south, wrapping into the storms' eastern quadrant. At 5 a.m. EDT (0900 UTC) on July 12 the center of Hurricane Celia was located near 16.2 north latitude and 127.9 west longitude. That's about 1,260 miles (2,025 km) west-southwest of the southern tip of Baja California, Mexico. It was moving to the west-northwest at 10 mph (17 kph) and NOAA's National Hurricane Center (NHC) expects Celia to turn toward the northwest later today, with this motion continuing Tuesday night and Wednesday. Maximum sustained winds were near 100 mph (155 kph). NHC forecasts weakening over the next two days and Celia could weaken to a <span class="hlt">tropical</span> storm on Wednesday. Read more: NASA Sees Hurricane Celia Headed for <span class="hlt">Central</span> <span class="hlt">Pacific</span> Credit: NASA/Goddard/Jeff Schmaltz/MODIS Land Rapid Response Team NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.A11E0101M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.A11E0101M"><span>Vertical Eddy Diffusivity as a Control Parameter in the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Martinez Avellaneda, N.; Cornuelle, B.; Mazloff, M. R.; Stammer, D.</p> <p>2012-12-01</p> <p>Ocean models suffer from errors in the treatment of turbulent sub-grid scale motions causing mixing and energy dissipation. Unrealistic small-scale features in models can have large-scale consequences, such as biases in the upper ocean temperature, a symptom of poorly-simulated upwelling, currents and air-sea interactions. This is of special importance in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean, which is home to energetic air-sea interactions that affect global climate. It has been shown in a number of studies that the simulated ENSO variability is highly dependent on the state of the ocean (e.g.: background mixing). Moreover, the magnitude of the vertical numerical diffusion is of primary importance in properly reproducing the <span class="hlt">Pacific</span> equatorial thermocline. Yet, it is a common practice to use spatially uniform mixing parameters in ocean simulations. This work is part of a NASA-funded project to estimate the space-varying ocean mixing coefficients in an eddy-permitting model of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. The usefulness of assimilation techniques in estimating mixing parameters has been previously explored (e.g.: Stammer, 2005, Ferreira et al., 2005). The authors also demonstrated that the spatial structure of the Equatorial Undercurrent (EUC) could be improved by adjusting wind-stress and surface buoyancy flux within their error bounds. In our work, we address the important question of whether adjusting mixing parameterizations can bring about similar improvements. To that end, an eddy-permitting state estimate for the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> is developed using the MIT general circulation model and its adjoint where the vertical diffusivity is set as a control parameter. Complementary adjoint-based sensitivity results show strong sensitivities of the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> thermocline (thickness and location) and the EUC transport to the vertical diffusivity in the <span class="hlt">tropics</span>. Argo, CTD, XBT and mooring in-situ data, as well as TMI SST and altimetry observations are assimilated in order to reduce</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li class="active"><span>5</span></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_5 --> <div id="page_6" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li class="active"><span>6</span></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="101"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70155275','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70155275"><span>The regional forcing of Northern hemisphere drought during recent warm <span class="hlt">tropical</span> west <span class="hlt">Pacific</span> Ocean La Niña events</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Hoell, Andrew; Funk, Christopher C.; Mathew Barlow,</p> <p>2014-01-01</p> <p>Northern Hemisphere circulations differ considerably between individual El Niño-Southern Oscillation events due to internal atmospheric variability and variation in the zonal location of sea surface temperature forcing over the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean. This study examines the similarities between recent Northern Hemisphere droughts associated with La Niña events and anomalously warm <span class="hlt">tropical</span> west <span class="hlt">Pacific</span> sea surface temperatures during 1988–1989, 1998–2000, 2007–2008 and 2010–2011 in terms of the hemispheric-scale circulations and the regional forcing of precipitation over North America and Asia during the cold season of November through April. The continental precipitation reductions associated with recent <span class="hlt">central</span> <span class="hlt">Pacific</span> La Niña events were most severe over North America, eastern Africa, the Middle East and southwest Asia. High pressure dominated the entire Northern Hemisphere mid-latitudes and weakened and displaced storm tracks northward over North America into <span class="hlt">central</span> Canada. Regionally over North America and Asia, the position of anomalous circulations within the zonal band of mid-latitude high pressure varied between each La Niña event. Over the northwestern and southeastern United States and southern Asia, the interactions of anomalous circulations resulted in consistent regional temperature advection, which was subsequently balanced by similar precipitation-modifying vertical motions. Over the <span class="hlt">central</span> and northeastern United States, the spatial variation of anomalous circulations resulted in modest inter-seasonal temperature advection variations, which were balanced by varying vertical motion and precipitation patterns. Over the Middle East and eastern Africa, the divergence of moisture and the advection of dry air due to anomalous circulations enhanced each of the droughts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27988772','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27988772"><span>New records of sabellids and serpulids (Polychaeta: Sabellidae, Serpulidae) from the <span class="hlt">Tropical</span> Eastern <span class="hlt">Pacific</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bastida-Zavala, J Rolando; Buelna, Alondra Sofía Rodríguez; DE León-González, Jesús Angel; Camacho-Cruz, Karla Andrea; Carmona, Isabel</p> <p>2016-11-07</p> <p>Sabellids and serpulids are two well represented families in the polychaete fauna of the <span class="hlt">Tropical</span> Eastern <span class="hlt">Pacific</span>, with 31 and 34 species respectively; however, most records come from the Gulf of California or the western coast of Baja California Peninsula. Only a few records are from localities in the large expanse of the <span class="hlt">central</span> and southern Mexican <span class="hlt">Pacific</span>. Thus, sabellids and serpulids were collected from several shallow water habitats along the coast of Mexican <span class="hlt">Pacific</span>, such as coastal lagoons, coral reefs, rocky shores and from man-made structures as marinas, piers and ships of several harbors; additionally, specimens from national collections were revised. More than 8,400 specimens of sabellids and serpulids from the states of Baja California, Baja California Sur, Sonora, Sinaloa, Michoacán, Guerrero, Oaxaca and Chiapas, and some specimens from Panamá and Perú were examined. In the present work we record new localities of four sabellids and 24 serpulids. One sabellid, Branchiomma bairdi, is an exotic/invasive species in Oaxaca, Sinaloa and Baja California Sur, while four species of serpulids are exotic and/or cryptogenic species: Ficopomatus uschakovi, Hydroides dirampha, H. elegans and H. sanctaecrucis. Additionally, the geographical range has been extended for five species: the sabellids Pseudobranchiomma punctata from Oahu, Hawaii to La Paz Bay, and Parasabella pallida from California to Puerto Escondido, Baja California Sur; and for three serpulids, Hydroides inermis from the Galápagos Islands to Agua Blanca, Oaxaca, H. gairacensis from Panamá to Puerto Ángel, Oaxaca, and H. panamensis from Panamá to Huatulco, Oaxaca and Faro de Bucerías, Michoacán. Hydroides cf. amri, previously recorded as H. brachyacantha from Oahu, Hawaii, is more similar to H. amri from Australia. The number of sabellids recorded for the <span class="hlt">Tropical</span> Eastern <span class="hlt">Pacific</span> increased to 33, the serpulid species to 35.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140013014','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140013014"><span>The Precipitation Response Over the Continental United States to Cold <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Sea Surface Temperatures</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wang, Hailan; Schubert, Siegfried D.</p> <p>2013-01-01</p> <p>The dominant pattern of annual mean SST variability in the <span class="hlt">Pacific</span> (in its cold phase) produces pronounced precipitation deficits over the continental United States (U.S.) throughout the annual cycle. This study investigates the physical and dynamical processes through which the cold <span class="hlt">Pacific</span> pattern affects the U.S. precipitation, particularly the causes for the peak dry impacts in fall, as well as the nature of the differences between the summer and fall responses. Results, based on observations and reanalyses, show that the peak precipitation deficit over the U.S. during fall is primarily due to reduced atmospheric moisture transport from the Gulf of Mexico into the <span class="hlt">central</span> and eastern U.S., and secondarily due to a reduction in local evaporation from land-atmosphere feedback. The former is associated with a strong and systematic low-level northeasterly flow anomaly over the southeastern U.S. that counteracts the northwest branch of the climatological flow associated with the north Atlantic subtropical high. The above northeasterly anomaly is maintained by both diabatic heating anomalies in the nearby Intra-American Seas and diabatic cooling anomalies in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. In contrast, the modest summertime precipitation deficit over the U.S. is mainly the result of local land-atmosphere feedback; the rather weak and disorganized atmospheric circulation anomalies over and to the south of the U.S. make little contribution. An evaluation of NSIPP-1 AGCM simulations shows it to be deficient in simulating the warm season <span class="hlt">tropical</span> convection responses over the Intra-American Seas to the cold <span class="hlt">Pacific</span> pattern and thereby the precipitation responses over the U.S., a problem that appears to be common to many AGCMs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMPP51C..05A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMPP51C..05A"><span>Multiproxy reconstruction of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Holocene temperature gradients and water column structure</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arbuszewski, J. A.; Oppo, D.; Huang, K.; Dubois, N.; Galy, V.; Mohtadi, M.; Herbert, T.; Rosenthal, Y.; Linsley, B. K.</p> <p>2012-12-01</p> <p>The El Niño-Southern Oscillation (ENSO) is the most prominent mode of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> climate variability and has the potential to significantly impact the climate of the Indo-<span class="hlt">Pacific</span> region and globally1. In the past, the mean state of the <span class="hlt">Pacific</span> Ocean has, at times, resembled El Niño or La Niña conditions2. Although the dynamical relationships responsible for these changes have been studied through paleoproxy reconstructions and climate modeling, many questions remain. Recent paleoproxy based studies of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> hydrology and surface temperature variability have hypothesized that observed climatological changes over the Holocene are directly linked to ENSO and/or mean state variability, complementing studies that dynamically relate centennial scale ENSO variability to mean state changes3-8. These studies have suggested that mid Holocene ENSO variability was low and the mean state was more "La Niña" like3-6. In the late Holocene, paleoproxy data has been interpreted as indicating an increase in ENSO variability with a more moderate mean ocean state3-6. However, alternative explanations could exist. Here, we test the hypothesis that observed climatological changes in the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> are related to mean state or ENSO variability during the Holocene. We focus our study on two sets of cores from the equatorial <span class="hlt">Pacific</span>, with one located in the Indo-<span class="hlt">Pacific</span> Warm Pool (BJ803-119 GGC, 117MC, sedimentation rates ~29 cm/kyr) and the other just off the Galapagos in the heart of the Eastern Cold Tongue (KNR195-5 43 GGC, 42MC, sedimentation rates ~20cm/kyr). The western site lies in the region predicted by models to show the greatest variations in temperature and water column structure in response to mean state changes, while the eastern site lies in the area most prone to changes due to ENSO variability7. Together, these sites allow us the best chance to robustly reconstruct ENSO and mean state related changes. We use a multiproxy approach and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017NatCC...7..123C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017NatCC...7..123C"><span>Projected increase in El Niño-driven <span class="hlt">tropical</span> cyclone frequency in the <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chand, Savin S.; Tory, Kevin J.; Ye, Hua; Walsh, Kevin J. E.</p> <p>2017-02-01</p> <p>The El Niño/Southern Oscillation (ENSO) drives substantial variability in <span class="hlt">tropical</span> cyclone (TC) activity around the world. However, it remains uncertain how the projected future changes in ENSO under greenhouse warming will affect TC activity, apart from an expectation that the overall frequency of TCs is likely to decrease for most ocean basins. Here we show robust changes in ENSO-driven variability in TC occurrence by the late twenty-first century. In particular, we show that TCs become more frequent (~20-40%) during future-climate El Niño events compared with present-climate El Niño events--and less frequent during future-climate La Niña events--around a group of small island nations (for example, Fiji, Vanuatu, Marshall Islands and Hawaii) in the <span class="hlt">Pacific</span>. We examine TCs across 20 models from the Coupled Model Intercomparison Project phase 5 database, forced under historical and greenhouse warming conditions. The 12 most realistic models identified show a strong consensus on El Niño-driven changes in future-climate large-scale environmental conditions that modulate development of TCs over the off-equatorial western <span class="hlt">Pacific</span> and the <span class="hlt">central</span> North <span class="hlt">Pacific</span> regions. These results have important implications for climate change and adaptation pathways for the vulnerable <span class="hlt">Pacific</span> island nations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PalOc..31..491T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PalOc..31..491T"><span>South <span class="hlt">Pacific</span> hydrologic and cyclone variability during the last 3000 years</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Toomey, Michael R.; Donnelly, Jeffrey P.; Tierney, Jessica E.</p> <p>2016-04-01</p> <p>Major excursions in the position of the South <span class="hlt">Pacific</span> Convergence Zone (SPCZ) and/or changes in its intensity are thought to drive <span class="hlt">tropical</span> cyclone (TC) and precipitation variability across much of the <span class="hlt">central</span> South <span class="hlt">Pacific</span>. A lack of conventional sites typically used for multimillennial proxy reconstructions has limited efforts to extend observational rainfall/TC data sets and our ability to fully assess the risks posed to <span class="hlt">central</span> <span class="hlt">Pacific</span> islands by future changes in fresh water availability or the frequency of storm landfalls. Here we use the sedimentary record of Apu Bay, offshore the island of Tahaa, French Polynesia, to explore the relationship between SPCZ position/intensity and <span class="hlt">tropical</span> cyclone overwash, resolved at decadal time scales, since 3200 years B.P. Changes in orbital precession and <span class="hlt">Pacific</span> sea surface temperatures best explain evidence for a coordinated pattern of rainfall variability at Tahaa and across the <span class="hlt">Pacific</span> over the late Holocene. Our companion record of <span class="hlt">tropical</span> cyclone activity from Tahaa suggests major storm activity was higher between 2600-1500 years B.P., when decadal scale SPCZ variability may also have been stronger. A transition to lower storm frequency and a shift or expansion of the SPCZ toward French Polynesia around 1000 years B.P. may have prompted Polynesian migration into the <span class="hlt">central</span> <span class="hlt">Pacific</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4653143','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4653143"><span>Airborne measurements of organic bromine compounds in the <span class="hlt">Pacific</span> <span class="hlt">tropical</span> tropopause layer</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Navarro, Maria A.; Atlas, Elliot L.; Saiz-Lopez, Alfonso; Rodriguez-Lloveras, Xavier; Kinnison, Douglas E.; Lamarque, Jean-Francois; Tilmes, Simone; Filus, Michal; Harris, Neil R. P.; Meneguz, Elena; Ashfold, Matthew J.; Manning, Alistair J.; Cuevas, Carlos A.; Schauffler, Sue M.; Donets, Valeria</p> <p>2015-01-01</p> <p>Very short-lived brominated substances (VSLBr) are an important source of stratospheric bromine, an effective ozone destruction catalyst. However, the accurate estimation of the organic and inorganic partitioning of bromine and the input to the stratosphere remains uncertain. Here, we report near-tropopause measurements of organic brominated substances found over the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> during the NASA Airborne <span class="hlt">Tropical</span> Tropopause Experiment campaigns. We combine aircraft observations and a chemistry−climate model to quantify the total bromine loading injected to the stratosphere. Surprisingly, despite differences in vertical transport between the Eastern and Western <span class="hlt">Pacific</span>, VSLBr (organic + inorganic) contribute approximately similar amounts of bromine [∼6 (4−9) parts per thousand] to the stratospheric input at the <span class="hlt">tropical</span> tropopause. These levels of bromine cause substantial ozone depletion in the lower stratosphere, and any increases in future abundances (e.g., as a result of aquaculture) will lead to larger depletions. PMID:26504212</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUSMIN23A..07F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUSMIN23A..07F"><span>Training on Eastern <span class="hlt">Pacific</span> <span class="hlt">tropical</span> cyclones for Latin American students</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Farfán, L. M.; Raga, G. B.</p> <p>2009-05-01</p> <p><span class="hlt">Tropical</span> cyclones are one of the most impressive atmospheric phenomena and their development in the Atlantic and Eastern <span class="hlt">Pacific</span> basins has potential to affect several Latin-American and Caribbean countries, where human resources are limited. As part of an international research project, we are offering short courses based on the current understanding of <span class="hlt">tropical</span> cyclones in the Eastern <span class="hlt">Pacific</span> basin. Our main goal is to train students from higher-education institutions from various countries in Latin America. Key aspects are <span class="hlt">tropical</span> cyclone formation and evolution, with particular emphasis on their development off the west coast of Mexico. Our approach includes lectures on <span class="hlt">tropical</span> cyclone climatology and formation, dynamic and thermodynamic models, air-sea interaction and oceanic response, ocean waves and coastal impacts as well as variability and climate-related predictions. In particular, we use a best-track dataset issued by the United States National Hurricane Center and satellite observations to analyze convective patterns for the period 1970-2006. Case studies that resulted in landfall over northwestern Mexico are analyzed in more detail; this includes systems that developed during the 2006, 2007 and 2008 seasons. Additionally, we have organized a human-dimensions symposium to discuss socio-economic issues that are associated with the landfall of <span class="hlt">tropical</span> cyclones. This includes coastal zone impact and flooding, the link between cyclones and water resources, the flow of weather and climate information from scientists to policy- makers, the role of emergency managers and decision makers, impact over health issues and the viewpoint of the insurance industry.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ClDy...50.1221W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ClDy...50.1221W"><span>Spatiotemporal change of intraseasonal oscillation intensity over the <span class="hlt">tropical</span> Indo-<span class="hlt">Pacific</span> Ocean associated with El Niño and La Niña events</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wu, Renguang; Song, Lei</p> <p>2018-02-01</p> <p>The present study analyzes the intraseasonal oscillation (ISO) intensity change over the <span class="hlt">tropical</span> Indo-<span class="hlt">Pacific</span> associated with the El Niño-Southern Oscillation (ENSO) and compares the intensity change between El Niño and La Niña years and between the 10-20-day and 30-60-day ISOs. The ISO intensity change tends to be opposite between El Niño and La Niña years in the developing and mature phases. The intensity change features a contrast between the <span class="hlt">tropical</span> southeastern Indian Ocean and the <span class="hlt">tropical</span> western North <span class="hlt">Pacific</span> (WNP) in the developing phases and between the Maritime Continent and the <span class="hlt">tropical</span> <span class="hlt">central</span> <span class="hlt">Pacific</span> in the mature phase. In the decaying phases, the intensity change shows notable differences between El Niño and La Niña events and between fast and slow decaying El Niño events. Large intensity change is observed over the <span class="hlt">tropical</span> WNP in the developing summer, over the <span class="hlt">tropical</span> southeastern Indian Ocean in the developing fall, and over the <span class="hlt">tropical</span> WNP in the fast decaying El Niño summer due to a combined effect of vertical shear, vertical motion, and lower-level moisture. In the ENSO developing summer and in the El Niño decaying summer, the 10-20-day ISO intensity change displays a northwest-southeast tilted distribution over the <span class="hlt">tropical</span> WNP, whereas the large 30-60-day ISO intensity change is confined to the off-equatorial WNP. In the La Niña decaying summer, the 30-60-day ISO intensity change features a large zonal contrast across the Philippines, whereas the 10-20-day ISO intensity anomaly is characterized by a north-south contrast over the <span class="hlt">tropical</span> WNP.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25412536','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25412536"><span>[Nesting habitat characterization for Amazona oratrix (Psittaciformes: Psittacidae) in the <span class="hlt">Central</span> <span class="hlt">Pacific</span>, Mexico].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Monterrubio-Rico, Tiberio C; Álvarez-Jara, Margarito; Tellez-Garcia, Loreno; Tena-Morelos, Carlos</p> <p>2014-09-01</p> <p>-deciduous forest for nesting, with fewer nests in deciduous forest, while nesting in transformed agricultural fields was avoided. The main climatic variables associated with the potential distribution of nests were: mean temperature of wettest quarter, mean diurnal temperature range, and precipitation of wettest month. Suitable cli- matic conditions for the potential presence of nesting trees were present in 61% of the region; however, most of the area consisted of <span class="hlt">tropical</span> deciduous forests (55.8%), while semi-deciduous <span class="hlt">tropical</span> forests covered only 17% of the region. These results indicated the importance to conserve semi-deciduous forests as breeding habitats for the Yellow-headed Parrot, and revealed the urgent need to implement conservation and restoration actions. These should include a total ban of land use change in <span class="hlt">tropical</span> semi-deciduous forest areas, and for selective logging of all keystone tree species; besides, we recommend the establishment of wildlife sanctuaries in important nesting areas, and a series of <span class="hlt">tropical</span> forest restoration programs in the <span class="hlt">Central</span> <span class="hlt">Pacific</span> coast.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ClDy...50.4635W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ClDy...50.4635W"><span>Contributions of <span class="hlt">tropical</span> waves to <span class="hlt">tropical</span> cyclone genesis over the western North <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wu, Liang; Takahashi, Masaaki</p> <p>2018-06-01</p> <p>The present study investigates the relationship between the <span class="hlt">tropical</span> waves and the <span class="hlt">tropical</span> cyclone (TC) genesis over the western North <span class="hlt">Pacific</span> (WNP) for the period 1979-2011. Five wave types are considered in this study. It is shown that the TC genesis is strongly related to enhanced low-level vorticity and convection of <span class="hlt">tropical</span> waves and significant difference are detected in the TC modulation by dynamic and thermodynamic components of the waves. More TCs tend to form in regions of waves with overlapping cyclonic vorticity and active convection. About 83.2% of TCs form within active phase of <span class="hlt">tropical</span> waves, mainly in a single wave and two coexisting waves. Each wave type-related genesis accounts for about 30% of all TC geneses except for the Kelvin waves that account for only 25.2% of TC geneses. The number of each wave type-related TC genesis consistently varies seasonally with peak in the TC season (July-November), which is attributed to a combined effect of active wave probability and intensity change. The interannual variation in the TC genesis is well reproduced by the <span class="hlt">tropical</span> wave-related TC genesis, especially in the region east of 150°E. An eastward extension of the enhanced monsoon trough coincides with increased <span class="hlt">tropical</span> wave activity by accelerated wave-mean flow interaction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/circ/1312/','USGSPUBS'); return false;" href="https://pubs.usgs.gov/circ/1312/"><span>Ground Water on <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Islands - Understanding a Vital Resource</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Tribble, Gordon</p> <p>2008-01-01</p> <p>To a casual observer, <span class="hlt">tropical</span> <span class="hlt">Pacific</span> islands seem idyllic. Closer scrutiny reveals that their generally small size makes them particularly vulnerable to economic and environmental stresses imposed by rapidly growing populations, increasing economic development, and global climate change. On these islands, freshwater is one of the most precious resources. Ground water is the main source of drinking water on many islands, and for quite a few islands, it is the only reliable source of water throughout the year. Faced with a growing demand for this valuable resource, and the potential negative effects on its availability and quality from changes in global climate, increasingly sophisticated management approaches will be needed to ensure a dependable supply of freshwater for the residents of these islands. Much scientific information has been collected by the U.S. Geological Survey (USGS) and other organizations about the ground-water resources of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> islands. The aim of this Circular is to give members of the public, policymakers, and other stakeholders knowledge that will help ensure that this information can be used to make informed decisions about the management of these life-giving resources. As the demand for freshwater grows, new monitoring and research efforts will be needed to (1) characterize the extent and sustainability of ground-water resources on different <span class="hlt">tropical</span> <span class="hlt">Pacific</span> islands, (2) better understand linkages between ground-water discharge and freshwater and nearshore ecosystems, and (3) prepare for the effects of climate change, which will likely include the loss of habitable land and reduced areas for the accumulation of ground water as a result of rising sea levels.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20170010359','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20170010359"><span>Physical Processes Controlling the Spatial Distributions of Relative Humidity in the <span class="hlt">Tropical</span> Tropopause Layer Over the <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Jensen, Eric J.; Thornberry, Troy D.; Rollins, Andrew W.; Ueyama, Rei; Pfister, Leonhard; Bui, Thaopaul; Diskin, Glenn S.; Digangi, Joshua P.; Hintsa, Eric; Gao, Ru-Shan; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20170010359'); toggleEditAbsImage('author_20170010359_show'); toggleEditAbsImage('author_20170010359_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20170010359_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20170010359_hide"></p> <p>2017-01-01</p> <p>The spatial distribution of relative humidity with respect to ice (RHI) in the boreal wintertime <span class="hlt">tropical</span> tropopause layer (TTL, is asymptotically Equal to 14-18 km) over the <span class="hlt">Pacific</span> is examined with the measurements provided by the NASA Airborne <span class="hlt">Tropical</span> TRopopause EXperiment. We also compare the measured RHI distributions with results from a transport and microphysical model driven by meteorological analysis fields. Notable features in the distribution of RHI versus temperature and longitude include (1) the common occurrence of RHI values near ice saturation over the western <span class="hlt">Pacific</span> in the lower to middle TTL; (2) low RHI values in the lower TTL over the <span class="hlt">central</span> and eastern <span class="hlt">Pacific</span>; (3) common occurrence of RHI values following a constant mixing ratio in the middle to upper TTL (temperatures between 190 and 200 K); (4) RHI values typically near ice saturation in the coldest airmasses sampled; and (5) RHI values typically near 100% across the TTL temperature range in air parcels with ozone mixing ratios less than 50 ppbv. We suggest that the typically saturated air in the lower TTL over the western <span class="hlt">Pacific</span> is likely driven by a combination of the frequent occurrence of deep convection and the predominance of rising motion in this region. The nearly constant water vapor mixing ratios in the middle to upper TTL likely result from the combination of slow ascent (resulting in long residence times) and wave-driven temperature variability. The numerical simulations generally reproduce the observed RHI distribution features, and sensitivity tests further emphasize the strong influence of convective input and vertical motions on TTL relative humidity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22943626','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22943626"><span>No gene flow across the Eastern <span class="hlt">Pacific</span> Barrier in the reef-building coral Porites lobata.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Baums, Iliana B; Boulay, Jennifer N; Polato, Nicholas R; Hellberg, Michael E</p> <p>2012-11-01</p> <p>The expanse of deep water between the <span class="hlt">central</span> <span class="hlt">Pacific</span> islands and the continental shelf of the Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> is regarded as the world's most potent marine biogeographic barrier. During recurrent climatic fluctuations (ENSO, El Niño Southern Oscillation), however, changes in water temperature and the speed and direction of currents become favourable for trans-oceanic dispersal of larvae from <span class="hlt">central</span> <span class="hlt">Pacific</span> to marginal eastern <span class="hlt">Pacific</span> reefs. Here, we investigate the population connectivity of the reef-building coral Porites lobata across the Eastern <span class="hlt">Pacific</span> Barrier (EPB). Patterns of recent gene flow in samples (n = 1173) from the <span class="hlt">central</span> <span class="hlt">Pacific</span> and the Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> (ETP) were analysed with 12 microsatellite loci. Results indicated that P. lobata from the ETP are strongly isolated from those in the <span class="hlt">central</span> <span class="hlt">Pacific</span> and Hawaii (F(ct) ' = 0.509; P < 0.001). However, samples from Clipperton Atoll, an oceanic island on the eastern side of the EPB, grouped with the <span class="hlt">central</span> <span class="hlt">Pacific</span>. Within the <span class="hlt">central</span> <span class="hlt">Pacific</span>, Hawaiian populations were strongly isolated from three co-occurring clusters found throughout the remainder of the <span class="hlt">central</span> <span class="hlt">Pacific</span>. No further substructure was evident in the ETP. Changes in oceanographic conditions during ENSO over the past several thousand years thus appear insufficient to support larval deliveries from the <span class="hlt">central</span> <span class="hlt">Pacific</span> to the ETP or strong postsettlement selection acts on ETP settlers from the <span class="hlt">central</span> <span class="hlt">Pacific</span>. Recovery of P. lobata populations in the frequently disturbed ETP thus must depend on local larval sources. © 2012 Blackwell Publishing Ltd.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15...47K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15...47K"><span>Developing an enhanced <span class="hlt">tropical</span> cyclone data portal for the Southern Hemisphere and the Western <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kuleshov, Yuriy; de Wit, Roald; Atalifo, Terry; Prakash, Bipendra; Waqaicelua, Alipate; Kunitsugu, Masashi; Caroff, Philippe; Chane-Ming, Fabrice</p> <p>2013-04-01</p> <p><span class="hlt">Tropical</span> cyclones are the most extreme weather phenomena which severely impact coastal communities and island nations. There is an ongoing research (i) on accurate analysis of observed trends in <span class="hlt">tropical</span> cyclone occurrences, and (ii) how <span class="hlt">tropical</span> cyclone frequency and intensity may change in the future as a result of climate change. Reliable historical records of cyclone activity are vital for this research. The <span class="hlt">Pacific</span> Australia Climate Change Science and Adaptation Planning (PACCSAP) program is dedicated to help <span class="hlt">Pacific</span> Island countries and Timor Leste gain a better understanding of how climate change will impact their regions. One of the key PACCSAP projects is focused on developing a <span class="hlt">tropical</span> cyclone archive, climatology and seasonal prediction for the regions. As part of the project, historical <span class="hlt">tropical</span> cyclone best track data have been examined and prepared to be subsequently displayed through the enhanced <span class="hlt">tropical</span> cyclone data portal for the Southern Hemisphere and the Western <span class="hlt">Pacific</span> Ocean. Data from the Regional Specialised Meteorological Centre (RSMC) Nadi, Fiji and <span class="hlt">Tropical</span> Cyclone Warning Centres (TCWCs) in Brisbane, Darwin and Wellington for 1969-1970 to 2010-2011 <span class="hlt">tropical</span> cyclone seasons have been carefully examined. Errors and inconsistencies which have been found during the quality control procedure have been corrected. To produce a consolidated data set for the South <span class="hlt">Pacific</span> Ocean, best track data from these four centres have been used. Specifically, for 1969-1970 to 1994-1995 <span class="hlt">tropical</span> cyclone seasons, data from TCWCs in Brisbane, Darwin and Wellington have been used. In 1995, RSMC Nadi, Fiji has been established with responsibilities for issuing <span class="hlt">tropical</span> cyclone warnings and preparing best track data for the area south of the equator to 25°S, 160°E to 120°W. Consequently, data from RSMC Nadi have been used as a primary source for this area, starting from the 1995-1996 <span class="hlt">tropical</span> cyclone season. These data have been combined with the data from</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120016656','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120016656"><span>Electrically-Active Convection in <span class="hlt">Tropical</span> Easterly Waves and Implications for <span class="hlt">Tropical</span> Cyclogenesis in the Atlantic and East <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Leppert, Kenneth D., II; Petersen, Walter A.; Cecil, Daniel J.</p> <p>2012-01-01</p> <p>In this study, we investigate the characteristics of <span class="hlt">tropical</span> easterly wave convection and the possible implications of convective structure on <span class="hlt">tropical</span> cyclogenesis and intensification over the Atlantic Ocean and East <span class="hlt">Pacific</span> using data from the <span class="hlt">Tropical</span> Rainfall Measurement Mission Microwave Imager, Precipitation Radar (PR), and Lightning Imaging Sensor as well as infrared (IR) brightness temperature data from the NASA global-merged IR brightness temperature dataset. Easterly waves were partitioned into northerly, southerly, trough, and ridge phases based on the 700-hPa meridional wind from the NCEP-NCAR reanalysis dataset. Waves were subsequently divided according to whether they did or did not develop <span class="hlt">tropical</span> cyclones (i.e., developing and nondeveloping, respectively), and developing waves were further subdivided according to development location. Finally, composites as a function of wave phase and category were created using the various datasets. Results suggest that the convective characteristics that best distinguish developing from nondeveloping waves vary according to where developing waves spawn <span class="hlt">tropical</span> cyclones. For waves that developed a cyclone in the Atlantic basin, coverage by IR brightness temperatures .240 K and .210 K provide the best distinction between developing and nondeveloping waves. In contrast, several variables provide a significant distinction between nondeveloping waves and waves that develop cyclones over the East <span class="hlt">Pacific</span> as these waves near their genesis location including IR threshold coverage, lightning flash rates, and low-level (<4.5 km) PR reflectivity. Results of this study may be used to help develop thresholds to better distinguish developing from nondeveloping waves and serve as another aid for <span class="hlt">tropical</span> cyclogenesis forecasting.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018NatCC...8..493M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018NatCC...8..493M"><span>Model <span class="hlt">tropical</span> Atlantic biases underpin diminished <span class="hlt">Pacific</span> decadal variability</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>McGregor, Shayne; Stuecker, Malte F.; Kajtar, Jules B.; England, Matthew H.; Collins, Mat</p> <p>2018-06-01</p> <p><span class="hlt">Pacific</span> trade winds have displayed unprecedented strengthening in recent decades1. This strengthening has been associated with east <span class="hlt">Pacific</span> sea surface cooling2 and the early twenty-first-century slowdown in global surface warming2,3, amongst a host of other substantial impacts4-9. Although some climate models produce the timing of these recently observed trends10, they all fail to produce the trend magnitude2,11,12. This may in part be related to the apparent model underrepresentation of low-frequency <span class="hlt">Pacific</span> Ocean variability and decadal wind trends2,11-13 or be due to a misrepresentation of a forced response1,14-16 or a combination of both. An increasingly prominent connection between the <span class="hlt">Pacific</span> and Atlantic basins has been identified as a key driver of this strengthening of the <span class="hlt">Pacific</span> trade winds12,17-20. Here we use targeted climate model experiments to show that combining the recent Atlantic warming trend with the typical climate model bias leads to a substantially underestimated response for the <span class="hlt">Pacific</span> Ocean wind and surface temperature. The underestimation largely stems from a reduction and eastward shift of the atmospheric heating response to the <span class="hlt">tropical</span> Atlantic warming trend. This result suggests that the recent <span class="hlt">Pacific</span> trends and model decadal variability may be better captured by models with improved mean-state climatologies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19900026718&hterms=nitrate&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dnitrate','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19900026718&hterms=nitrate&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dnitrate"><span>Nitrate in the atmospheric boundary layer of the <span class="hlt">tropical</span> South <span class="hlt">Pacific</span> - Implications regarding sources and transport</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Savoie, Dennis L.; Prospero, Joseph M.; Merrill, John T.; Uematsu, Mitsuo</p> <p>1989-01-01</p> <p>Weekly bulk aerosol samples collected at three sites in the <span class="hlt">tropical</span> South <span class="hlt">Pacific</span> from 1983 to 1987 are analyzed. The mean nitrate concentrations obtained for the sites range from 0.107 to 0.117 microg/cu m. The results suggest that the region is minimally affected by the transport of soil material and pollutants from the continents. Measurements from sites in the <span class="hlt">tropical</span> North <span class="hlt">Pacific</span> show mean nitrate concentrations that are about three times higher than those in the South <span class="hlt">Pacific</span>, showing that the North <span class="hlt">Pacific</span> is significantly impacted by the transport of material from Asia and North America. The relationships between the nitrate concentrations to other constituents at American Samoa are discussed, including nonseasalt sulfate, Pb-210, and Be-7.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70156478','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70156478"><span>Considering native and exotic terrestrial reptiles in island invasive species eradication programmes in the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Fisher, Richard N.; Veitch, C.R.; Clout, Mike N.; Towns, D. R.</p> <p>2010-01-01</p> <p>Most island restoration projects with reptiles, either as direct beneficiaries of conservation or as indicators of recovery responses, have been on temperate or xeric islands. There have been decades of research, particularly on temperate islands in New Zealand, on the responses of native reptiles to mammal eradications but very few studies in <span class="hlt">tropical</span> insular systems. Recent increases in restoration projects involving feral mammal eradications in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> have led to several specific challenges related to native and invasive reptiles. This paper reviews these challenges and discusses some potential solutions to them. The first challenge is that the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> herpetofauna is still being discovered, described and understood. There is thus incomplete knowledge of how eradication activities may affect these faunas and the potential risks facing critical populations of these species from these eradication actions. The long term benefit of the removal of invasives is beneficial, but the possible short term impacts to small populations on small islands might be significant. The second challenge is that protocols for monitoring the responses of these species are not well documented but are often different from those used in temperate or xeric habitats. Lizard monitoring techniques used in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> are discussed. The third challenge involves invasive reptiles already in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, some of which could easily spread accidentally through eradication and monitoring operations. The species posing the greatest threats in this respect are reviewed, and recommendations for biosecurity concerning these taxa are made.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/10367648','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/10367648"><span>Weights, hematology, and serum chemistry of free-ranging brown boobies (Sula leucogaster) in Johnston Atoll, <span class="hlt">Central</span> <span class="hlt">Pacific</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Work, T M</p> <p>1999-03-01</p> <p>Hematologic and serum chemistry values are reported for 105 brown boobies (Sula leucogaster) from Johnston Atoll, <span class="hlt">Central</span> <span class="hlt">Pacific</span>. Hematocrit, estimated total plasma solids, total and differential white cell counts, serum glucose, calcium, phosphorus, uric acid, total protein, albumin, globulin, aspartate aminotransferase, and creatinine phosphokinase were analyzed. Hematologic and serum chemistry values varied with age and sex. Values were compared with those of red-footed boobies and other <span class="hlt">tropical</span> and temperate marine pelecaniforms.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li class="active"><span>6</span></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_6 --> <div id="page_7" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active"><span>7</span></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="121"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/1004018','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/1004018"><span>Weights, hematology and serum chemistry of free-ranging brown boobies (Sula leucogaster) in Johnston Atoll, <span class="hlt">Central</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Work, Thierry M.</p> <p>1999-01-01</p> <p>Hematologic and serum chemistry values are reported for 105 brown boobies (Sula leucogaster) from Johnston Atoll, <span class="hlt">Central</span> <span class="hlt">Pacific</span>. Hematocrit, estimated total plasma solids, total and differential white cell counts, serum glucose, calcium, phosphorus, uric acid, total protein, albumin, globulin, aspartate aminotransferase, and creatinine phosphokinase were analyzed. Hematologic and serum chemistry values varied with age and sex. Values were compared with those of red-footed boobies and other <span class="hlt">tropical</span> and temperate marine pelecaniforms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ClDy..tmp..271Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ClDy..tmp..271Z"><span>Seasonal prediction of the typhoon genesis frequency over the Western North <span class="hlt">Pacific</span> with a Poisson regression model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Xinchang; Zhong, Shanshan; Wu, Zhiwei; Li, Yun</p> <p>2017-06-01</p> <p>This study investigates the typhoon genesis frequency (TGF) in the dominant season (July to October) in Western North <span class="hlt">Pacific</span> (WNP) using observed data in 1965-2015. Of particular interest is the predictability of the TGF and associated preseason sea surface temperature (SST) in the <span class="hlt">Pacific</span>. It is found that, the TGF is positively related to a tri-polar pattern of April SST anomalies in North <span class="hlt">Pacific</span> (NP{T}_{Apr}), while it is negatively related to SST anomalies over the Coral Sea (CSS{T}_{Apr}) off east coast of Australia. The NP{T}_{Apr} leads to large anomalous cyclonic circulation over North <span class="hlt">Pacific</span>. The anomalous southwesterly weakens the northeast trade wind, decreases evaporation, and induces warm water in <span class="hlt">central</span> <span class="hlt">tropical</span> North <span class="hlt">Pacific</span>. As such, the warming effect amplifies the temperature gradient in <span class="hlt">central</span> <span class="hlt">tropical</span> North <span class="hlt">Pacific</span>, which in turn maintains the cyclonic wind anomaly in the west <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, which favors the typhoon genesis in WNP. In the South <span class="hlt">Pacific</span>, the CSS{T}_{Apr} supports the typhoon formation over the WNP by (a) strengthening the cross-equatorial flows and enhancing the Inter-<span class="hlt">tropical</span> Convergence Zone; (b) weakening southeast and northeast trade wind, and keeping continuous warming in the center of <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. The influence of both NP{T}_{Apr} and CSS{T}_{Apr} can persistently affect the zonal wind in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> and induce conditions favorable for the typhoon genesis in the typhoon season. A Poisson regression model using NP{T}_{Apr} and CSS}{T}_{Apr} is developed to predict the TGF and a promising skill is achieved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1911226C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1911226C"><span>Global warming and <span class="hlt">tropical</span> <span class="hlt">Pacific</span> sea surface temperature: Why models and observations do not agree</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Coats, Sloan; Karnauskas, Kristopher</p> <p>2017-04-01</p> <p>The pattern of sea surface temperature (SST) in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean provides an important control on global climate, necessitating an understanding of how this pattern will change in response to anthropogenic radiative forcing. State-of-the-art climate models from the Coupled Model Intercomparison Project phase 5 (CMIP5) overwhelmingly project a decrease in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> zonal SST gradient over the coming century. This decrease is, in part, a response of the ocean to a weakening Walker circulation in the CMIP5 models, a consequence of the mass and energy balances of the hydrologic cycle identified by Held and Soden (2006). CMIP5 models, however, are not able to reproduce the observed increase in the zonal SST gradient between 1900-2013 C.E., which we argue to be robust using advanced statistical techniques and new observational datasets. While this increase is suggestive of the ocean dynamical thermostat mechanism of Clement et al. (1996), we provide evidence that a strengthening Equatorial Undercurrent (EUC) also contributes to eastern equatorial <span class="hlt">Pacific</span> cooling. Importantly, the strengthening EUC is a response of the ocean to a weakening Walker circulation and thus can help to reconcile the range of opposing theories and observations of anthropogenic climate change in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean. Because of a newly identified bias in their simulation of equatorial coupled atmosphere-ocean dynamics, however, CMIP5 models do not capture the magnitude of the response of the EUC to anthropogenic radiative forcing. Consequently, they project a continuation of the opposite to what has been observed in the real world, with potentially serious consequences for projected climate impacts that are influenced by the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120009046','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120009046"><span>Climate Variability and Phytoplankton in the <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rousseaux, Cecile</p> <p>2012-01-01</p> <p>The effect of climate variability on phytoplankton communities was assessed for the <span class="hlt">tropical</span> and sub-<span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean between 1998 and 2005 using an established biogeochemical assimilation model. The phytoplankton communities exhibited wide range of responses to climate variability, from radical shifts in the Equatorial <span class="hlt">Pacific</span>, to changes of only a couple of phytoplankton groups in the North <span class="hlt">Central</span> <span class="hlt">Pacific</span>, to no significant changes in the South <span class="hlt">Pacific</span>. In the Equatorial <span class="hlt">Pacific</span>, climate variability dominated the variability of phytoplankton. Here, nitrate, chlorophyll and all but one of the 4 phytoplankton types (diatoms, cyanobacteria and coccolithophores) were strongly correlated (p<0.01) with the Multivariate El Nino Southern Oscillation Index (MEI). In the North <span class="hlt">Central</span> <span class="hlt">Pacific</span>, MEI and chlorophyll were significantly (p<0.01) correlated along with two of the phytoplankton groups (chlorophytes and coccolithophores). Ocean biology in the South <span class="hlt">Pacific</span> was not significantly correlated with MEI. During La Nina events, diatoms increased and expanded westward along the cold tongue (correlation with MEI, r=-0.81), while cyanobacteria concentrations decreased significantly (r=0.78). El Nino produced the reverse pattern, with cyanobacteria populations increasing while diatoms plummeted. The diverse response of phytoplankton in the different major basins of the <span class="hlt">Pacific</span> suggests the different roles climate variability can play in ocean biology.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26634438','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26634438"><span>Dynamical excitation of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean and ENSO variability by Little Ice Age cooling.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Rustic, Gerald T; Koutavas, Athanasios; Marchitto, Thomas M; Linsley, Braddock K</p> <p>2015-12-18</p> <p><span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Ocean dynamics during the Medieval Climate Anomaly (MCA) and the Little Ice Age (LIA) are poorly characterized due to a lack of evidence from the eastern equatorial <span class="hlt">Pacific</span>. We reconstructed sea surface temperature, El Niño-Southern Oscillation (ENSO) activity, and the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> zonal gradient for the past millennium from Galápagos ocean sediments. We document a mid-millennium shift (MMS) in ocean-atmosphere circulation around 1500-1650 CE, from a state with dampened ENSO and strong zonal gradient to one with amplified ENSO and weak gradient. The MMS coincided with the deepest LIA cooling and was probably caused by a southward shift of the intertropical convergence zone. The peak of the MCA (900-1150 CE) was a warm period in the eastern <span class="hlt">Pacific</span>, contradicting the paradigm of a persistent La Niña pattern. Copyright © 2015, American Association for the Advancement of Science.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JOL....36....4Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JOL....36....4Y"><span>The IOD-ENSO precursory teleconnection over the <span class="hlt">tropical</span> Indo-<span class="hlt">Pacific</span> Ocean: dynamics and long-term trends under global warming</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yuan, Dongliang; Hu, Xiaoyue; Xu, Peng; Zhao, Xia; Masumoto, Yukio; Han, Weiqing</p> <p>2018-01-01</p> <p>The dynamics of the teleconnection between the Indian Ocean Dipole (IOD) in the <span class="hlt">tropical</span> Indian Ocean and El Niño-Southern Oscillation (ENSO) in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean at the time lag of one year are investigated using lag correlations between the oceanic anomalies in the southeastern <span class="hlt">tropical</span> Indian Ocean in fall and those in the <span class="hlt">tropical</span> Indo-<span class="hlt">Pacific</span> Ocean in the following winter-fall seasons in the observations and in high-resolution global ocean model simulations. The lag correlations suggest that the IOD-forced interannual transport anomalies of the Indonesian Throughflow generate thermocline anomalies in the western equatorial <span class="hlt">Pacific</span> Ocean, which propagate to the east to induce ocean-atmosphere coupled evolution leading to ENSO. In comparison, lag correlations between the surface zonal wind anomalies over the western equatorial <span class="hlt">Pacific</span> in fall and the Indo-<span class="hlt">Pacific</span> oceanic anomalies at time lags longer than a season are all insignificant, suggesting the short memory of the atmospheric bridge. A linear continuously stratified model is used to investigate the dynamics of the oceanic connection between the <span class="hlt">tropical</span> Indian and <span class="hlt">Pacific</span> Oceans. The experiments suggest that interannual equatorial Kelvin waves from the Indian Ocean propagate into the equatorial <span class="hlt">Pacific</span> Ocean through the Makassar Strait and the eastern Indonesian seas with a penetration rate of about 10%-15% depending on the baroclinic modes. The IOD-ENSO teleconnection is found to get stronger in the past century or so. Diagnoses of the CMIP5 model simulations suggest that the increased teleconnection is associated with decreased Indonesian Throughflow transports in the recent century, which is found sensitive to the global warming forcing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMPP43D..04A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMPP43D..04A"><span>An Coral Ensemble Approach to Reconstructing <span class="hlt">Central</span> <span class="hlt">Pacific</span> Climate Change During the Holocene</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Atwood, A. R.; Cobb, K. M.; Grothe, P. R.; Sayani, H. R.; Southon, J. R.; Edwards, R. L.; Deocampo, D.; Chen, T.; Townsend, K. J.; Hagos, M. M.; Chiang, J. C. H.</p> <p>2016-12-01</p> <p>The processes that control El Niño-Southern Oscillation (ENSO) variability on long timescales are still poorly understood. As a consequence, limited progress has been made in understanding how ENSO will change under greenhouse gas forcing. The mid-Holocene provides a well-defined target to study the fundamental controls of ENSO variability. A large number of paleo-ENSO records spanning the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> indicate that ENSO variability was reduced by as much as 50% between 3000-6000 yr BP, relative to modern times. Dynamical models of ENSO suggest that ENSO properties can shift in response to changes in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> mean state and/or seasonal cycle, but few proxy records can resolve such changes during the interval in question with enough accuracy. While decades of research have demonstrated the fidelity of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> coral d18O records to quantify interannual temperature and precipitation anomalies associated with ENSO, substantial mean offsets exist across overlapping coral sequences that have made it difficult to quantify past changes in mean climate. Here, we test a new approach to reconstruct changes in mean climate from coral records using a large ensemble of bulk d18O measurements on radiometrically-dated fossil corals from Christmas Island that span the Holocene. In contrast to the traditional method of high-resolution sampling to reconstruct monthly climate conditions, we implement a bulk approach, which dramatically reduces the analysis time needed to estimate mean coral d18O and enables a large number of corals to be analyzed in the production of an ensemble of mean climate estimates. A pseudo-coral experiment based on simulations with a Linear Inverse Model and a coupled GCM is used to determine the number of bulk coral estimates that are required to resolve a given mean climate perturbation. In addition to these bulk measurements, short transects are sampled at high resolution to constrain changes in the amplitude of the seasonal cycle</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018DyAtO..81...42H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018DyAtO..81...42H"><span>Decrease of <span class="hlt">tropical</span> cyclone genesis frequency in the western North <span class="hlt">Pacific</span> since 1960s</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hu, Feng; Li, Tim; Liu, Jia; Bi, Mingyu; Peng, Melinda</p> <p>2018-03-01</p> <p><span class="hlt">Tropical</span> cyclone (TC) genesis frequency in the western North <span class="hlt">Pacific</span> (WNP) during 1960-2014 shows a step-by-step decrease on interdecadal timescale, in accordance to the phase of the Interdecadal <span class="hlt">Pacific</span> Oscillation (IPO). The environmental parameters responsible for the interdecadal change of TC genesis frequency were investigated. It was found that vertical wind shear especially the zonal wind shear plays a critical role, while other parameters such as sea surface temperature (SST), vertical velocity, divergence, humidity and maximum potential intensity cannot explain the step-by-step decrease of TC genesis frequency. A further diagnosis shows that the interdecadal change of vertical wind shear is caused by SST and associated rainfall pattern changes across the Indo-<span class="hlt">Pacific</span> Ocean. A stronger warming in the Indian Ocean/western <span class="hlt">Pacific</span> from 1960-1976 to 1977-1998 led to enhanced convection over the Maritime Continent and thus strengthened vertical shear over the key TC genesis region in the WNP. A La Nina-like SST pattern change from 1977-1998 to 1999-2014 led to a strengthened Walker circulation in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, which further enhanced the vertical shear and decreased TC genesis frequency in the WNP.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/1225146-understanding-el-nino-like-oceanic-response-tropical-pacific-global-warming','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/1225146-understanding-el-nino-like-oceanic-response-tropical-pacific-global-warming"><span>Understanding the El Niño-like Oceanic Response in the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> to Global Warming</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Luo, Yiyong; Lu, Jian; Liu, Fukai</p> <p></p> <p>The enhanced <span class="hlt">central</span> and eastern <span class="hlt">Pacific</span> SST warming and the associated ocean processes under global warming are investigated using the ocean component of the Community Earth System Model (CESM), Parallel Ocean Program version 2 (POP2). The <span class="hlt">tropical</span> SST warming pattern in the coupled CESM can be faithfully reproduced by the POP2 forced with surface fluxes computed using the aerodynamic bulk formula. By prescribing the wind stress and/or wind speed through the bulk formula, the effects of wind stress change and/or the wind-evaporation-SST (WES) feedback are isolated and their linearity is evaluated in this ocean-alone setting. Result shows that, although themore » weakening of the equatorial easterlies contributes positively to the El Niño-like SST warming, 80% of which can be simulated by the POP2 without considering the effects of wind change in both mechanical and thermodynamic fluxes. This result points to the importance of the air-sea thermal interaction and the relative feebleness of the ocean dynamical process in the El Niño-like equatorial <span class="hlt">Pacific</span> SST response to global warming. On the other hand, the wind stress change is found to play a dominant role in the oceanic response in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, accounting for most of the changes in the equatorial ocean current system and thermal structures, including the weakening of the surface westward currents, the enhancement of the near-surface stratification and the shoaling of the equatorial thermocline. Interestingly, greenhouse gas warming in the absence of wind stress change and WES feedback also contributes substantially to the changes at the subsurface equatorial <span class="hlt">Pacific</span>. Further, this warming impact can be largely replicated by an idealized ocean experiment forced by a uniform surface heat flux, whereby, arguably, a purest form of oceanic dynamical thermostat is revealed.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19990061897','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19990061897"><span>Measurements of Acidic Gases and Aerosol Species Aboard the NASA DC-8 Aircraft During the <span class="hlt">Pacific</span> Exploratory Mission in the <span class="hlt">Tropics</span> (PEM-<span class="hlt">Tropics</span> A)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Talbot, Robert W.; Dibb, Jack E.</p> <p>1999-01-01</p> <p>We received funding to provide measurements of nitric acid (HNO3), formic acid (HCOOH), acetic acid (CH3COOH), and the chemical composition of aerosols aboard the NASA Ames DC-8 research aircraft during the PEM-<span class="hlt">Tropics</span> A mission. These measurements were successfully completed and the final data resides in the electronic archive (ftp-gte.larc.nasa.gov) at NASA Langley Research Center. For the PEM-<span class="hlt">Tropics</span> A mission the University of New Hampshire group was first author of four different manuscripts. Three of these have now appeared in the Journal of Geophysical Research-Atmospheres, included in the two section sections on PEM-<span class="hlt">Tropics</span> A. The fourth manuscript has just recently been submitted to this same journal as a stand alone paper. All four of these papers are included in this report. The first paper (Influence of biomass combustion emissions on the distribution of acidic trace gases over the Southern <span class="hlt">Pacific</span> basin during austral springtime) describes the large-scale distributions of HNO3, HCOOH, and CH3COOH. Arguments were presented to show, particularly in the middle tropospheric region, that biomass burning emissions from South America and Africa were a major source of acidic gases over the South <span class="hlt">Pacific</span> basin. The second paper (Aerosol chemical composition and distribution during the <span class="hlt">Pacific</span> Exploratory Mission (PEM) <span class="hlt">Tropics</span>) covers the aerosol aspects of our measurement package. Compared to acidic gases, O3, and selected hydrocarbons, the aerosol chemistry showed little influence from biomass burning emissions. The data collected in the marine boundary layer showed a possible marine source of NH3 to the troposphere in equatorial areas. This source had been speculated on previously, but our data was the first collected from an airborne platform to show its large-scale features. The third paper (Constraints on the age and dilution of <span class="hlt">Pacific</span> Exploratory Mission-<span class="hlt">Tropics</span> biomass burning plumes from the natural radionuclide tracer Pb-210) utilized the unexpectedly</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMOS23E1271L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMOS23E1271L"><span>Effects of Hydrothermal Scavenging of 230Th in the Eastern Equatorial <span class="hlt">Pacific</span> Translated to the Deep Waters of the <span class="hlt">Central</span> Equatorial <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lopez, G. I.; Marcantonio, F.</p> <p>2014-12-01</p> <p>Although we were not involved in the 2013 US GEOTRACES zonal transect in the eastern <span class="hlt">tropical</span> south <span class="hlt">Pacific</span>, our results in the <span class="hlt">central</span> <span class="hlt">tropical</span> <span class="hlt">Pacific</span> are complementary in that they shed light on the extensive hydrothermal plume emanating from the East <span class="hlt">Pacific</span> Rise (EPR). Specifically, we have analyzed dissolved 230Th concentrations at high-resolution within the water column at two locations (ML1208-12CTD; 8° 19.989' N, 159° 18.000' W, and ML1208-03CTD; 00° 13.166' S, 155° 57.668' W) sampled as part of a cruise to the Line Islands. The pattern of the dissolved 230Th concentration profile at 8°N is essentially linear from the surface to 2000 m and generally follows a reversible scavenging model. However, from 2000 m to 3000 m, the dissolved 230Th concentrations are constant, before linearly increasing again from 3000 m to the bottom. At this site dissolved 230Th concentrations range from 1.06 fg/kg at 100 m to 55.15 fg/kg at 4600 m. At the equator, dissolved 230Th concentrations are slightly lower, and range from undetectable at 25 m to 19.07 fg/kg at 3038 m. A nearly indistinguishable pattern in dissolved 230Th concentrations occurs in the profile at the equator compared to that from 8°N. The deep-water deviation from linearity between 2 and 3 km in the 230Th profiles (lower concentrations than expected) at both sites coincides well with the interval of the water column which has the highest concentrations of 3He. This 3He-rich signal has been traced to hydrothermal plumes from the EPR, thousands of km away (Lupton et al., 1998). We hypothesize that the lower concentrations of 230Th in deep waters of the <span class="hlt">central</span> equatorial <span class="hlt">Pacific</span> are a result of: 1) scavenging of water-column 230Th by Fe-Mn particulates contained within the EPR hydrothermal plume, and 2) lateral export of these 230Th-deficient deep waters approximately 7000 km westward. We will discuss the implications that the transport of this signature across vast distances has on water residence and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMPP43D..07E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMPP43D..07E"><span>Coherent anti-phasing between solar forcing and <span class="hlt">tropical</span> <span class="hlt">Pacific</span> climate over the past millennium: derivation and implications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Emile-Geay, J.; Cobb, K.; Mann, M. E.; Wittenberg, A. T.</p> <p>2011-12-01</p> <p>Using a compilation of the most recent, high-resolution proxy data from the <span class="hlt">tropics</span>, and a state-of-the-art climate reconstruction technique (RegEM iTTLS; Emile-Geay et al, submitted), we reconstruct sea-surface temperature (SST) in the <span class="hlt">central</span> equatorial <span class="hlt">Pacific</span> (NINO3.4 region) over the past millennium. Using frozen network experiments and pseudoproxy validation, the reconstruction is found skillful back to 1150 C.E., with inevitable amplitude reduction before 1500 C.E. due to the paucity of proxy predictors. Despite this caveat, wavelet coherency analysis reveals a marked anticorrelation between solar forcing (as estimated from cosmogenic isotope concentrations; Bard et al., 2007; Steinhilber et al., 2009) and the reconstructed NINO3.4 in the ~sim205-year spectral range (DeVries cycle). The phase angle between both signals is 156 ± 33o in this range, indicating that periods of high solar irradiance coincide with cool conditions in the NINO3.4 region, with time lag of 14 ± 19 years. We find this result robust to the reconstruction method, estimate of solar forcing, or analysis method used to estimate the phasing. We then discuss the implication of this result for the response of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> climate to radiative forcing. While the anti-phasing seems to favor the ``ocean dynamical thermostat'' hypothesis of Clement et al [1996], this feedback appears subdued in most IPCC-class coupled general circulation models (CGCMs), where it is almost completely compensated by changes in the <span class="hlt">Pacific</span> trade winds, linked to changes in the vertical structures of atmospheric moisture and temperature (Knutson & Manabe 1995; Held & Soden 2006; Vecchi et al. 2006). If the reconstruction is correct that past NINO3.4 SSTs have varied out of phase with solar irradiance on bicentennial scales, this would pose a new challenge both for CGCM simulations and for our understanding of the equatorial <span class="hlt">Pacific</span> response to radiative forcing Clement, A. C., Seager, R., Cane, M. A., and Zebiak</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140010886','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140010886"><span>Stationarity of the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Teleconnection to North America in CMIP5 PMIP3 Model Simulations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Coats, Sloan; Smerdon, Jason E.; Cook, Benjamin I.; Seager, Richard</p> <p>2013-01-01</p> <p>The temporal stationarity of the teleconnection between the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean and North America (NA) is analyzed in atmosphere-only, and coupled last-millennium, historical, and control runs from the Coupled Model Intercomparison Project Phase 5 data archive. The teleconnection, defined as the correlation between December-January-February (DJF) <span class="hlt">tropical</span> <span class="hlt">Pacific</span> sea surface temperatures (SSTs) and DJF 200 mb geopotential height, is found to be nonstationary on multidecadal timescales. There are significant changes in the spatial features of the teleconnection over NA in continuous 56-year segments of the last millennium and control simulations. Analysis of atmosphere-only simulations forced with observed SSTs indicates that atmospheric noise cannot account for the temporal variability of the teleconnection, which instead is likely explained by the strength of, and multidecadal changes in, <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean variability. These results have implications for teleconnection-based analyses of model fidelity in simulating precipitation, as well as any reconstruction and forecasting efforts that assume stationarity of the observed teleconnection.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNG51B..03R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNG51B..03R"><span>Characterizing Transitions Between Decadal States of the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> using State Space Reconstruction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ramesh, N.; Cane, M. A.</p> <p>2017-12-01</p> <p>The complex coupled ocean-atmosphere system of the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> generates variability on timescales from intraseasonal to multidecadal. <span class="hlt">Pacific</span> Decadal Variability (PDV) is among the key drivers of global climate, with effects on hydroclimate on several continents, marine ecosystems, and the rate of global mean surface temperature rise under anthropogenic greenhouse gas forcing. Predicting phase shifts in the PDV would therefore be highly useful. However, the small number of PDV phase shifts that have occurred in the observational record pose a substantial challenge to developing an understanding of the mechanisms that underlie decadal variability. In this study, we use a 100,000-year unforced simulation from an intermediate-complexity model of the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> region that has been shown to produce PDV comparable to that in the real world. We apply the Simplex Projection method to the NINO3 index from this model to reconstruct a shadow manifold that preserves the topology of the true attractor of this system. We find that the high- and low-variance phases of PDV emerge as a pair of regimes in a 3-dimensional state space, and that the transitions between decadal states lie in a highly predictable region of the attractor. We then use a random forest algorithm to develop a physical interpretation of the processes associated with these highly-predictable transitions. We find that transitions to low-variance states are most likely to occur approximately 2.5 years after an El Nino event, and that ocean-atmosphere variables in the southeastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> play a crucial role in driving these transitions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1998JGR...10318649L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1998JGR...10318649L"><span>Effects of subsurface ocean dynamics on instability waves in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lawrence, Sean P.; Allen, Myles R.; Anderson, David L. T.; Llewellyn-Jones, David T.</p> <p>1998-08-01</p> <p><span class="hlt">Tropical</span> instability waves in a primitive equation model of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean, forced with analyzed wind stresses updated daily, show unexpectedly close phase correspondence with observation through the latter half of 1992. This suggests that these waves are not pure instabilities developing from infinitesimal disturbances, but that their phases and phase speeds are at least partially determined by the wind stress forcing. To quantify and explain this observation, we perfomed several numerical experiments, which indicate that remotely forced Rossby waves can influence both the phase and phase speed of <span class="hlt">tropical</span> instability waves. We suggest that a remote wind forcing determines the high model/observation phase correspondence of <span class="hlt">tropical</span> instability waves through a relatively realistic simulation of equatorial Kelvin and Rossby wave activity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.H13Q..04M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.H13Q..04M"><span>Impacts of <span class="hlt">Pacific</span> SSTs on California Winter Precipitation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Myoung, B.; Kafatos, M.</p> <p>2017-12-01</p> <p>Consecutive below-normal precipitation years and resulted multi-year droughts are critical issues as the recent 2012-2015 drought of California caused tremendous socio-economic damages. However, studies on the causes of the multi-year droughts lack. In this study, focusing on the three multi-year droughts (1999-2002, 2007-2009, and 2012-2015) in California during the last two decades, we investigated the atmospheric and oceanic characteristics of the three drought events for winter (December-February, DJF) in order to understand large-scale circulations that are responsible for initiation, maintenance, and termination of the droughts. It was found that abnormally developed upper-tropospheric ridges over the North <span class="hlt">Pacific</span> are primarily responsible for precipitation deficits and then droughts. These ridges developed when negative sea surface temperature anomalies (SSTs) including La Niña events are pervasive in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. After 3 or 4 years, the droughts ended under the opposite conditions; upper-tropospheric troughs in the North <span class="hlt">Pacific</span> with El Niño events in the <span class="hlt">tropics</span>. Results of Empirical Orthogonal Function (EOF) analysis for the 41-year (1974/75-2014/15) 500 hPa geopotential height in DJF revealed that, during the drought periods, the positive phases of the first and second EOF mode (EOF1+ and EOF2+, respectively) were active one by one, positioning upper-tropospheric ridges over the North <span class="hlt">Pacific</span>. While EOF1+ is associated with cold <span class="hlt">tropical</span> <span class="hlt">central</span> <span class="hlt">Pacific</span> and negative <span class="hlt">Pacific</span> Decadal Oscillation (PDO), EOF2+ is associated with the <span class="hlt">tropical</span> east-west SST dipole pattern (i.e., warm western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> and cool eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> near the southern Peru). Based on these results, we developed a regression model for winter precipitation. While dominant SST factors differ by decades, for the recent two decades (1994/1995-2014/2015), 56% variability of DJF precipitation is explained by the <span class="hlt">tropical</span> east-west SST dipole pattern and PDO (NINO3</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007JGRC..112.1012D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007JGRC..112.1012D"><span>Alkyl nitrate (C1-C3) depth profiles in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dahl, E. E.; Yvon-Lewis, S. A.; Saltzman, E. S.</p> <p>2007-01-01</p> <p>This paper reports the first depth profile measurements of methyl, ethyl, isopropyl and n-propyl nitrates in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean. Depth profile measurements were made at 22 stations during the Project Halocarbon Air Sea Exchange cruise, in warm pool, equatorial, subequatorial, and gyre waters. The highest concentrations, up to several hundred pM of methyl nitrate, were observed in the <span class="hlt">central</span> <span class="hlt">Pacific</span> within 8 degrees of the equator. In general, alkyl nitrate levels were highest in the surface mixed layer, and decreased with depth below the mixed layer. The spatial distribution of the alkyl nitrates suggests that there is a strong source associated with biologically productive ocean regions, that is characterized by high ratios of methyl:ethyl nitrate. However, the data do not allow discrimination between direct biological emissions and photochemistry as production mechanisms. Alkyl nitrates were consistently detectable at several hundred meters depth. On the basis of the estimated chemical loss rate of these compounds, we conclude that deep water alkyl nitrates must be produced in situ. Possible sources include free radical processes initiated by radioactive decay or cosmic rays, enzymatically mediated reactions involving bacteria, or unidentified chemical mechanisms involving dissolved organic matter.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMPP33B1323M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMPP33B1323M"><span>Reconstructing Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> productivity across Marine Isotope Stage 3 using foraminifera faunal counts</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>McCourty, M.; Schmidt, M. W.; Glaubke, R.; Hertzberg, J. E.; Marcantonio, F.; Bianchi, T. S.</p> <p>2017-12-01</p> <p>The El Niño-Southern Oscillation is one of Earth's largest sources of interannual climate variability that has many global environmental impacts. Furthermore, the mean state of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> has the potential to change in the near future due to anthropogenic warming of the planet. In order to provide an analogue for future climate states, there is a critical need to understand how the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> evolved across abrupt warming events in Earth's recent past. While most studies have focused on the evolution of ENSO across Marine Isotope Stages (MIS) 1 and 2, the dynamics of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> across the abrupt climate events of MIS 3 are still highly contentious. To develop a record of past changes in upwelling intensity in the EEP, a parameter critically linked to the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> mean state, we quantify the faunal abundances of 6 planktonic foraminifera species from piston core MV1014-02-17JC (00° 10.83'S, 85° 52.00'W; 2846 m depth) on the Carnegie Ridge from 35 - 59 kyr. The relative abundance of Globigerina bulloides, a species associated with upwelling conditions, and 5 other planktonic foraminifera suggest an increase in water column productivity during Heinrich Event 4 and across several Dansgaard-Oeschger stadial intervals. Initial results suggest that stadials in the North Atlantic are associated with more permanent La Niña-like conditions in the EEP. However, multiple lines of evidence suggest that depth intervals in our core between 43.7 - 55.7 kyr were impacted by intense dissolution due to changes in bottom water chemistry, impacting the fidelity of our faunal count records across this interval. Future work includes extending our faunal record back to 100 kyr to include Heinrich Events 6 - 8.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20020039695&hterms=impacts+ocean&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dimpacts%2Bocean','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20020039695&hterms=impacts+ocean&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dimpacts%2Bocean"><span>The Impacts of Daily Surface Forcing in the Upper Ocean over <span class="hlt">Tropical</span> <span class="hlt">Pacific</span>: A Numerical Study</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sui, C.-H.; Rienecker, Michele M.; Li, Xiaofan; Lau, William K.-M.; Laszlo, Istvan; Pinker, Rachel T.</p> <p>2001-01-01</p> <p><span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Ocean is an important region that affects global climate. How the ocean responds to the atmospheric surface forcing (surface radiative, heat and momentum fluxes) is a major topic in oceanographic research community. The ocean becomes warm when more heat flux puts into the ocean. The monthly mean forcing has been used in the past years since daily forcing was unavailable due to the lack of observations. The daily forcing is now available from the satellite measurements. This study investigates the response of the upper ocean over <span class="hlt">tropical</span> <span class="hlt">Pacific</span> to the daily atmospheric surface forcing. The ocean surface heat budgets are calculated to determine the important processes for the oceanic response. The differences of oceanic responses between the eastern and western <span class="hlt">Pacific</span> are intensively discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMPP33A2106L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMPP33A2106L"><span>ENSO-driven nutrient variability recorded by <span class="hlt">central</span> equatorial <span class="hlt">Pacific</span> corals</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>LaVigne, M.; Nurhati, I. S.; Cobb, K. M.; McGregor, H. V.; Sinclair, D. J.; Sherrell, R. M.</p> <p>2012-12-01</p> <p>Recent evidence for shifts in global ocean primary productivity suggests that surface ocean nutrient availability is a key link between global climate and ocean carbon cycling. Time-series records from satellite, in situ buoy sensors, and bottle sampling have documented the impact of the El Niño Southern Oscillation (ENSO) on equatorial <span class="hlt">Pacific</span> hydrography and broad changes in biogeochemistry since the late 1990's, however, data are sparse prior to this. Here we use a new paleoceanographic nutrient proxy, coral P/Ca, to explore the impact of ENSO on nutrient availability in the <span class="hlt">central</span> equatorial <span class="hlt">Pacific</span> at higher-resolution than available from in situ nutrient data. Corals from Christmas (157°W 2°N) and Fanning (159°W 4°N) Islands recorded a well-documented decrease in equatorial upwelling as a ~40% decrease in P/Ca during the 1997-98 ENSO cycle, validating the application of this proxy to <span class="hlt">Pacific</span> Porites corals. We compare the biogeochemical shifts observed through the 1997-98 event with two pre-TOGA-TAO ENSO cycles (1982-83 and 1986-87) reconstructed from a longer Christmas Island core. All three corals revealed ~30-40% P/Ca depletions during ENSO warming as a result of decreased regional wind stress, thermocline depth, and equatorial upwelling velocity. However, at the termination of each El Niño event, surface nutrients did not return to pre-ENSO levels for ~4-12 months after, SST as a result of increased biological draw down of surface nutrients. These records demonstrate the utility of high-resolution coral nutrient archives for understanding the impact of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> climate on the nutrient and carbon cycling of this key region.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active"><span>7</span></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_7 --> <div id="page_8" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="141"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1999JGR...104.3501K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1999JGR...104.3501K"><span>Molecular distributions of water soluble dicarboxylic acids in marine aerosols over the <span class="hlt">Pacific</span> Ocean including <span class="hlt">tropics</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kawamura, Kimitaka; Sakaguchi, Futoshi</p> <p>1999-02-01</p> <p>Remote marine aerosols collected over the western North to equatorial <span class="hlt">Pacific</span> (34°N-14°S, 140°E-150°W) were studied for low molecular weight dicarboxylic acids using a capillary gas chromatography (GC) and GC/mass spectrometer, and for total carbon and nitrogen contents. Homologous series of dicarboxylic acids (C2-C10) including keto- and hydroxy-dicarboxylic acids were detected in the samples with a concentration range of 10-250 ng m-3 (average 63 ng m-3 and median 44 ng m-3). Their molecular distributions showed a predominance of oxalic acid (C2), followed by malonic acid (C3). The smallest diacid (C2, 6.5-161 ng m-3 with average 40 ng m-3 and median 17 ng m-3) composed 45-75% (average 65%) of the total diacids. The diacids showed higher concentrations in the western <span class="hlt">Pacific</span> rim near Japanese islands and showed lower concentrations in the <span class="hlt">central</span> and <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. However, relative abundances of the diacid-carbon in the total aerosol carbon (1.1-15.8%) were found to be higher in the equatorial <span class="hlt">central</span> <span class="hlt">Pacific</span>. These diacids are probably in situ produced in the <span class="hlt">Pacific</span> atmosphere by photochemical oxidation of gaseous and particulate precursors. Results of principal component analysis of individual diacid, coupled with an information on photochemical reactions, further support that C2 and C3 diacids are likely produced by the oxidation of C4 and longer-chain diacids, whereas longer-chain (C5-C10) diacids are produced through the oxidation of semivolatile fatty acids which are also oxidation products of unsaturated fatty acids. Concentrations of total C (0.069-5.27 μg m-3 with average 0.39 μg m-3 and median 0.15 μg m-3) and total N (0.026-1.44 μg m-3 with average 0.12 μg m-3 and median 0.077 μg m-3) were generally higher over the western <span class="hlt">Pacific</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4645176','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4645176"><span>Impacts of the ENSO Modoki and other <span class="hlt">Tropical</span> Indo-<span class="hlt">Pacific</span> Climate-Drivers on African Rainfall</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Preethi, B.; Sabin, T. P.; Adedoyin, J. A.; Ashok, K.</p> <p>2015-01-01</p> <p>The study diagnoses the relative impacts of the four known <span class="hlt">tropical</span> Indo-<span class="hlt">Pacific</span> drivers, namely, El Niño Southern Oscillation (ENSO), ENSO Modoki, Indian Ocean Dipole (IOD), and Indian Ocean Basin-wide mode (IOBM) on African seasonal rainfall variability. The canonical El Niño and El Niño Modoki are in general associated with anomalous reduction (enhancement) of rainfall in southern (northern) hemispheric regions during March-May season. However, both the El Niño flavours anomalously reduce the northern hemispheric rainfall during June-September. Interestingly, during boreal spring and summer, in many regions, the Indian Ocean drivers have influences opposite to those from <span class="hlt">tropical</span> <span class="hlt">Pacific</span> drivers. On the other hand, during the October-December season, the canonical El Niño and/or positive IOD are associated with an anomalous enhancement of rainfall in the Eastern Africa, while the El Niño Modoki events are associated with an opposite impact. In addition to the Walker circulation changes, the Indo-<span class="hlt">Pacific</span> drivers influence the African rainfall through modulating jet streams. During boreal summer, the El Niño Modoki and canonical El Niño (positive IOD) tend to weaken (strengthen) the <span class="hlt">tropical</span> easterly jet, and result in strengthening (weakening) and southward shift of African easterly jet. This anomalously reduces (enhances) rainfall in the <span class="hlt">tropical</span> north, including Sahelian Africa. PMID:26567458</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26567458','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26567458"><span>Impacts of the ENSO Modoki and other <span class="hlt">Tropical</span> Indo-<span class="hlt">Pacific</span> Climate-Drivers on African Rainfall.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Preethi, B; Sabin, T P; Adedoyin, J A; Ashok, K</p> <p>2015-11-16</p> <p>The study diagnoses the relative impacts of the four known <span class="hlt">tropical</span> Indo-<span class="hlt">Pacific</span> drivers, namely, El Niño Southern Oscillation (ENSO), ENSO Modoki, Indian Ocean Dipole (IOD), and Indian Ocean Basin-wide mode (IOBM) on African seasonal rainfall variability. The canonical El Niño and El Niño Modoki are in general associated with anomalous reduction (enhancement) of rainfall in southern (northern) hemispheric regions during March-May season. However, both the El Niño flavours anomalously reduce the northern hemispheric rainfall during June-September. Interestingly, during boreal spring and summer, in many regions, the Indian Ocean drivers have influences opposite to those from <span class="hlt">tropical</span> <span class="hlt">Pacific</span> drivers. On the other hand, during the October-December season, the canonical El Niño and/or positive IOD are associated with an anomalous enhancement of rainfall in the Eastern Africa, while the El Niño Modoki events are associated with an opposite impact. In addition to the Walker circulation changes, the Indo-<span class="hlt">Pacific</span> drivers influence the African rainfall through modulating jet streams. During boreal summer, the El Niño Modoki and canonical El Niño (positive IOD) tend to weaken (strengthen) the <span class="hlt">tropical</span> easterly jet, and result in strengthening (weakening) and southward shift of African easterly jet. This anomalously reduces (enhances) rainfall in the <span class="hlt">tropical</span> north, including Sahelian Africa.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4568235','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4568235"><span>Changing <span class="hlt">central</span> <span class="hlt">Pacific</span> El Niños reduce stability of North American salmon survival rates</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Kilduff, D. Patrick; Di Lorenzo, Emanuele; Botsford, Louis W.; Teo, Steven L. H.</p> <p>2015-01-01</p> <p><span class="hlt">Pacific</span> salmon are a dominant component of the northeast <span class="hlt">Pacific</span> ecosystem. Their status is of concern because salmon abundance is highly variable—including protected stocks, a recently closed fishery, and actively managed fisheries that provide substantial ecosystem services. Variable ocean conditions, such as the <span class="hlt">Pacific</span> Decadal Oscillation (PDO), have influenced these fisheries, while diminished diversity of freshwater habitats have increased variability via the portfolio effect. We address the question of how recent changes in ocean conditions will affect populations of two salmon species. Since the 1980s, El Niño Southern Oscillation (ENSO) events have been more frequently associated with <span class="hlt">central</span> <span class="hlt">tropical</span> <span class="hlt">Pacific</span> warming (CPW) rather than the canonical eastern <span class="hlt">Pacific</span> warming ENSO (EPW). CPW is linked to the North <span class="hlt">Pacific</span> Gyre Oscillation (NPGO), whereas EPW is linked to the PDO, different indicators of northeast <span class="hlt">Pacific</span> Ocean ecosystem productivity. Here we show that both coho and Chinook salmon survival rates along western North America indicate that the NPGO, rather than the PDO, explains salmon survival since the 1980s. The observed increase in NPGO variance in recent decades was accompanied by an increase in coherence of local survival rates of these two species, increasing salmon variability via the portfolio effect. Such increases in coherence among salmon stocks are usually attributed to controllable freshwater influences such as hatcheries and habitat degradation, but the unknown mechanism underlying the ocean climate effect identified here is not directly subject to management actions. PMID:26240365</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19910004519','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19910004519"><span><span class="hlt">Tropical</span> <span class="hlt">Pacific</span> moisture variability: Its detection, synoptic structure and consequences in the general circulation</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mcguirk, James P.</p> <p>1990-01-01</p> <p>Satellite data analysis tools are developed and implemented for the diagnosis of atmospheric circulation systems over the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean. The tools include statistical multi-variate procedures, a multi-spectral radiative transfer model, and the global spectral forecast model at NMC. Data include in-situ observations; satellite observations from VAS (moisture, infrared and visible) NOAA polar orbiters (including Tiros Operational Satellite System (TOVS) multi-channel sounding data and OLR grids) and scanning multichannel microwave radiometer (SMMR); and European Centre for Medium Weather Forecasts (ECHMWF) analyses. A primary goal is a better understanding of the relation between synoptic structures of the area, particularly <span class="hlt">tropical</span> plumes, and the general circulation, especially the Hadley circulation. A second goal is the definition of the quantitative structure and behavior of all <span class="hlt">Pacific</span> <span class="hlt">tropical</span> synoptic systems. Finally, strategies are examined for extracting new and additional information from existing satellite observations. Although moisture structure is emphasized, thermal patterns are also analyzed. Both horizontal and vertical structures are studied and objective quantitative results are emphasized.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMPP43D..03H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMPP43D..03H"><span>An ensemble approach to reconstructing 20th century climate trends in data-sparse regions of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> using young fossil corals</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hitt, N. T.; Cobb, K. M.; Sayani, H. R.; Grothe, P. R.; Atwood, A. R.; O'Connor, G.; Chen, T.; Hagos, M. M.; Deocampo, D.; Edwards, R. L.; Cheng, H.; Lu, Y.; Thompson, D. M.</p> <p>2016-12-01</p> <p>Sea-surface temperature (SST) variability in the <span class="hlt">central</span> <span class="hlt">tropical</span> <span class="hlt">Pacific</span> drives global-scale responses through atmospheric teleconnections, so the response of this region to anthropogenic forcing has important implications for regional climate responses in many areas. However, quantification of anthropogenic SST trends in the <span class="hlt">central</span> <span class="hlt">tropical</span> <span class="hlt">Pacific</span> is complicated by the fact that instrumental SST observations in this region are extremely limited prior to 1950, with trends of opposite sign observed across the various gridded instrumental datasets (Deser et al., 2010). Researchers have turned to multi-century coral records to reconstruct ocean temperatures through time, but the paucity of such records prohibits the generation of uncertainty estimates. In this study, we use a large collection of U/Th-dated fossil corals that to investigate a new ensemble approach to reconstructing temperature from the <span class="hlt">Central</span> <span class="hlt">Pacific</span> over the late 20th century. Here we combine monthly-resolved d18O and Sr/Ca from 8 5-14 year long coral records from Christmas Island (2°N, 157°W) to quantify temperature and hydrological trends in this region from 1930 to present. We compare our fossil coral ensemble reconstruction to a long modern coral core from this site that extends back to 1940, as well as to gridded SST datasets. We also provide the first well-replicated coral d18O and Sr/Ca records across both the 1997/98 and 2015/2016 El Nino events, comparing the strength of these two events in the context of long-term temperature trends observed in our longer reconstruction. We conclude that the fossil coral ensemble approach provides a robust means of reconstructing 20th century climate trends. Deser et al., 2010, GRL, doi: 10.1029/2010GL043321</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ClDy...50.3031C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ClDy...50.3031C"><span>Effect of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> and Indian Ocean warming since the late 1970s on wintertime Northern Hemispheric atmospheric circulation and East Asian climate interdecadal changes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chu, Cuijiao; Yang, Xiu-Qun; Sun, Xuguang; Yang, Dejian; Jiang, Yiquan; Feng, Tao; Liang, Jin</p> <p>2018-04-01</p> <p>Observation reveals that the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>-Indian Ocean (TPIO) has experienced a pronounced interdecadal warming since the end of the 1970s. Meanwhile, the wintertime midlatitude Northern Hemispheric atmospheric circulation and East Asian climate have also undergone substantial interdecadal changes. The effect of the TPIO warming on these interdecadal changes are identified by a suite of AMIP-type atmospheric general circulation model experiments in which the model is integrated from September 1948 to December 1999 with prescribed historical, observed realistic sea surface temperature (SST) in a specific region and climatological SST elsewhere. Results show that the TPIO warming reproduces quite well the observed Northern Hemispheric wintertime interdecadal changes, suggesting that these interdecadal changes primarily originate from the TPIO warming. However, each sub-region of TPIO has its own distinct contribution. Comparatively, the <span class="hlt">tropical</span> <span class="hlt">central</span>-eastern <span class="hlt">Pacific</span> (TCEP) and <span class="hlt">tropical</span> western <span class="hlt">Pacific</span> (TWP) warming makes dominant contributions to the observed positive-phase PNA-like interdecadal anomaly over the North <span class="hlt">Pacific</span> sector, while the <span class="hlt">tropical</span> Indian Ocean (TIO) warming tends to cancel these contributions. Meanwhile, the TIO and TWP warming makes dominant contributions to the observed positive NAO-like interdecadal anomaly over the North Atlantic sector as well as the interdecadal anomalies over the Eurasian sector, although the TWP warming's contribution is relatively small. These remote responses are directly attributed to the TPIO warming-induced <span class="hlt">tropical</span> convection, rainfall and diabatic heating increases, in which the TIO warming has the most significant effect. Moreover, the TPIO warming excites a Gill-type pattern anomaly over the <span class="hlt">tropical</span> western <span class="hlt">Pacific</span>, with a low-level anticyclonic circulation anomaly over the Philippine Sea. Of three sub-regions, the TIO warming dominates such a pattern, although the TWP warming tends to cancel this effect</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMOS43C..03S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMOS43C..03S"><span>The impact of multi-decadal sub-surface circulation changes on sea surface chlorophyll patterns in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schollaert Uz, S.; Busalacchi, A. J.; Smith, T. M.; Evans, M. N.; Brown, C.; Hackert, E. C.; Wang, X.</p> <p>2016-12-01</p> <p>The <span class="hlt">tropical</span> <span class="hlt">Pacific</span> is a region of strong forcing where physical oceanography primarily controls biological variability over the seasonal to interannual time scales observed since dedicated ocean color satellite remote sensing began in 1997. To quantify how multi-decadal, climate-scale changes impact marine biological dynamics, we used the correlation with sea-surface temperature and height to reconstruct a 50-year time series of surface chlorophyll concentrations. The reconstruction demonstrates greatest skill away from the coast and within 10o of the equator where chlorophyll variance is greatest and primarily associated with El Niño Southern Oscillation (ENSO) dynamics and secondarily associated with decadal variability. We observe significant basin-wide differences between east and <span class="hlt">central</span> <span class="hlt">Pacific</span> events when the El Niño events are strong: chlorophyll increases with La Niña and decreases with El Niño, with larger declines east of 180o for remotely-forced east <span class="hlt">Pacific</span> events and west of 180o for locally-forced <span class="hlt">central</span> <span class="hlt">Pacific</span> events. Chlorophyll variations also reflect the physical dynamics of <span class="hlt">Pacific</span> decadal variability with small but significant differences between cool and warm eras: consistent with advection variability west of 180o and likely driven by subsurface changes in the nutricline depth between 110-140oW. Comparisons with output from a fully-coupled biogeochemical model support the hypothesis that this anomalous region is controlled by lower frequency changes in subsurface circulation patterns that transport nutrients to the surface. Basin-wide chlorophyll distributions exhibiting spatial heterogeneity in response to multi-decadal climate forcing imply similar long-term changes in phytoplankton productivity, with implications for the marine food web and the ocean's role as a carbon sink.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150022193','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150022193"><span>Stability of ENSO and Its <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Teleconnections over the Last Millennium</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lewis, Sophie; Legrande, A. N.</p> <p>2015-01-01</p> <p>Determining past changes in the amplitude, frequency and teleconnections of the El Nio Southern Oscillation (ENSO) is important for understanding its potential sensitivity to future anthropogenic climate change. Palaeo-reconstructions from proxy records provide long-term information of ENSO interactions with the background climatic state through time. However, it remains unclear how ENSO characteristics have changed through time, and precisely which signals proxies record. Proxy interpretations are underpinned by the assumption of stationarity in relationships between local and remote climates, and often utilise archives from single locations located in the <span class="hlt">Pacific</span> Ocean to reconstruct ENSO histories. Here, we investigate the stationarity of ENSO teleconnections using the Last Millennium experiment of CMIP5 (Coupled Model Intercomparison Project phase 5) (Taylor et al., 2012). We show that modelled ENSO characteristics vary on decadal- to centennial-scales, resulting from internal variability and external forcings, such as <span class="hlt">tropical</span> volcanic eruptions. Furthermore, the relationship between ENSO conditions and local climates across the <span class="hlt">Pacific</span> basin varies throughout the Last Millennium. Results show the stability of teleconnections is regionally dependent and proxies may reveal complex changes in teleconnected patterns, rather than large-scale changes in base ENSO characteristics. As such, proxy insights into ENSO likely require evidence to be synthesised over large spatial areas in order to deconvolve changes occurring in the NINO3.4 region from those pertaining to proxy-relevant local climatic variables. To obtain robust histories of the ENSO and its remote impacts, we recommend interpretations of proxy records should be considered in conjunction with palaeo-reconstructions from within the <span class="hlt">Central</span> <span class="hlt">Pacific</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20160004203','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20160004203"><span>The NASA Airborne <span class="hlt">Tropical</span> TRopopause EXperiment (ATTREX):High-Altitude Aircraft Measurements in the <span class="hlt">Tropical</span> Western <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Jensen, E. J.; Pfister, L.; Jordan, D. E.; Bui, T. V.; Ueyama, R.; Singh, H. B.; Lawson, P.; Thornberry, T.; Diskin, G.; McGill, M.; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20160004203'); toggleEditAbsImage('author_20160004203_show'); toggleEditAbsImage('author_20160004203_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20160004203_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20160004203_hide"></p> <p>2016-01-01</p> <p>The February through March 2014 deployment of the NASA Airborne <span class="hlt">Tropical</span> TRopopause EXperiment (ATTREX) provided unique in situ measurements in the western <span class="hlt">Pacific</span> <span class="hlt">Tropical</span> Tropopause Layer (TTL). Six flights were conducted from Guam with the long-range, high-altitude, unmanned Global Hawk aircraft. The ATTREX Global Hawk payload provided measurements of water vapor, meteorological conditions, cloud properties, tracer and chemical radical concentrations, and radiative fluxes. The campaign was partially coincident with the CONTRAST and CAST airborne campaigns based in Guam using lower-altitude aircraft The ATTREX dataset is being used for investigations of TTL cloud, transport, dynamical, and chemical processes as well as for evaluation and improvement of global-model representations of TTL processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ThApC.tmp..155F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ThApC.tmp..155F"><span>The phase differences of the interdecadal variabilities of <span class="hlt">tropical</span> cyclone activity in the peak and late seasons over the western North <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fan, Tingting; Xu, Shibin; Huang, Fei; Zhao, Jinping</p> <p>2018-04-01</p> <p>This study compares the interdecadal variations in <span class="hlt">tropical</span> cyclone (TC) activities over the western North <span class="hlt">Pacific</span> (WNP) basin during the peak season (July-September) and late season (October-December) of 1955-2014 and explores the possible physical mechanisms behind the variations. Both the peak- and late-season <span class="hlt">tropical</span> storm (TS) days show distinct interdecadal variations, while the late-season TS days lead the peak-season TS days by approximately 4 years on an interdecadal time scale. The late-season TC activity is related to the east-west sea surface temperature (SST) gradient across the equatorial <span class="hlt">Pacific</span>. The westerly winds induced by the SST gradient can reduce the vertical wind shear and increase the low-level vorticity, which favors TC genesis over the TC genesis region. The peak-season TC activity appears to relate to the SST gradient between the Indian Ocean and the <span class="hlt">Central</span> <span class="hlt">Pacific</span>. The westerly wind induced by the SST gradient can reduce the vertical wind shear and increase the mid-level relative humidity, thereby enhancing the TC activity. The full picture of the interdecadal variation in the WNP TC activity during the peak and late seasons revealed in this study provides a new perspective on the seasonal TC forecasts and future projections.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMOS43A1257B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMOS43A1257B"><span>Impact of Sea Surface Salinity on Coupled Dynamics for the <span class="hlt">Tropical</span> Indo <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Busalacchi, A. J.; Hackert, E. C.</p> <p>2014-12-01</p> <p>In this presentation we assess the impact of in situ and satellite sea surface salinity (SSS) observations on seasonal to interannual variability of <span class="hlt">tropical</span> Indo-<span class="hlt">Pacific</span> Ocean dynamics as well as on dynamical ENSO forecasts using a Hybrid Coupled Model (HCM) for 1993-2007 (cf., Hackert et al., 2011) and August 2011 until February 2014 (cf., Hackert et al., 2014). The HCM is composed of a primitive equation ocean model coupled with a SVD-based statistical atmospheric model for the <span class="hlt">tropical</span> Indo-<span class="hlt">Pacific</span> region. An Ensemble Reduced Order Kalman Filter (EROKF) is used to assimilate observations to constrain dynamics and thermodynamics for initialization of the HCM. Including SSS generally improves NINO3 sea surface temperature anomaly validation. Assimilating SSS gives significant improvement versus just subsurface temperature for all forecast lead times after 5 months. We find that the positive impact of SSS assimilation is brought about by surface freshening in the western <span class="hlt">Pacific</span> warm pool that leads to increased barrier layer thickness (BLT) and shallower mixed layer depths. Thus, in the west the net effect of assimilating SSS is to increase stability and reduce mixing, which concentrates the wind impact of ENSO coupling. Specifically, the main benefit of SSS assimilation for 1993-2007 comes from improvement to the Spring Predictability Barrier (SPB) period. In the east, the impact of Aquarius satellite SSS is to induce more cooling in the NINO3 region as a result of being relatively more salty than in situ SSS in the eastern <span class="hlt">Pacific</span> leading to increased mixing and entrainment. This, in turn, sets up an enhanced west to east SST gradient and intensified Bjerknes coupling. For the 2011-2014 period, consensus coupled model forecasts compiled by the IRI tend to erroneously predict NINO3 warming; SSS assimilation corrects this defect. Finally, we plan to update our analysis and report on the dynamical impact of including Aquarius SSS for the most-recent, ongoing 2014</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..14...79K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..14...79K"><span>Climate extremes in the <span class="hlt">Pacific</span>: improving seasonal prediction of <span class="hlt">tropical</span> cyclones and extreme ocean temperatures to improve resilience</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kuleshov, Y.; Jones, D.; Spillman, C. M.</p> <p>2012-04-01</p> <p>Climate change and climate extremes have a major impact on Australia and <span class="hlt">Pacific</span> Island countries. Of particular concern are <span class="hlt">tropical</span> cyclones and extreme ocean temperatures, the first being the most destructive events for terrestrial systems, while the latter has the potential to devastate ocean ecosystems through coral bleaching. As a practical response to climate change, under the <span class="hlt">Pacific</span>-Australia Climate Change Science and Adaptation Planning program (PACCSAP), we are developing enhanced web-based information tools for providing seasonal forecasts for climatic extremes in the Western <span class="hlt">Pacific</span>. <span class="hlt">Tropical</span> cyclones are the most destructive weather systems that impact on coastal areas. Interannual variability in the intensity and distribution of <span class="hlt">tropical</span> cyclones is large, and presently greater than any trends that are ascribable to climate change. In the warming environment, predicting <span class="hlt">tropical</span> cyclone occurrence based on historical relationships, with predictors such as sea surface temperatures (SSTs) now frequently lying outside of the range of past variability meaning that it is not possible to find historical analogues for the seasonal conditions often faced by <span class="hlt">Pacific</span> countries. Elevated SSTs are the primary trigger for mass coral bleaching events, which can lead to widespread damage and mortality on reef systems. Degraded coral reefs present many problems, including long-term loss of tourism and potential loss or degradation of fisheries. The monitoring and prediction of thermal stress events enables the support of a range of adaptive and management activities that could improve reef resilience to extreme conditions. Using the climate model POAMA (Predictive Ocean-Atmosphere Model for Australia), we aim to improve accuracy of seasonal forecasts of <span class="hlt">tropical</span> cyclone activity and extreme SSTs for the regions of Western <span class="hlt">Pacific</span>. Improved knowledge of extreme climatic events, with the assistance of tailored forecast tools, will help enhance the resilience and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ClDy...49..843X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ClDy...49..843X"><span>Evaluation of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> observing systems using NCEP and GFDL ocean data assimilation systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xue, Yan; Wen, Caihong; Yang, Xiaosong; Behringer, David; Kumar, Arun; Vecchi, Gabriel; Rosati, Anthony; Gudgel, Rich</p> <p>2017-08-01</p> <p>The TAO/TRITON array is the cornerstone of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> and ENSO observing system. Motivated by the recent rapid decline of the TAO/TRITON array, the potential utility of TAO/TRITON was assessed for ENSO monitoring and prediction. The analysis focused on the period when observations from Argo floats were also available. We coordinated observing system experiments (OSEs) using the global ocean data assimilation system (GODAS) from the National Centers for Environmental Prediction and the ensemble coupled data assimilation (ECDA) from the Geophysical Fluid Dynamics Laboratory for the period 2004-2011. Four OSE simulations were conducted with inclusion of different subsets of in situ profiles: all profiles (XBT, moorings, Argo), all except the moorings, all except the Argo and no profiles. For evaluation of the OSE simulations, we examined the mean bias, standard deviation difference, root-mean-square difference (RMSD) and anomaly correlation against observations and objective analyses. Without assimilation of in situ observations, both GODAS and ECDA had large mean biases and RMSD in all variables. Assimilation of all in situ data significantly reduced mean biases and RMSD in all variables except zonal current at the equator. For GODAS, the mooring data is critical in constraining temperature in the eastern and northwestern <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, while for ECDA both the mooring and Argo data is needed in constraining temperature in the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. The Argo data is critical in constraining temperature in off-equatorial regions for both GODAS and ECDA. For constraining salinity, sea surface height and surface current analysis, the influence of Argo data was more pronounced. In addition, the salinity data from the TRITON buoys played an important role in constraining salinity in the western <span class="hlt">Pacific</span>. GODAS was more sensitive to withholding Argo data in off-equatorial regions than ECDA because it relied on local observations to correct model biases and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110009949','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110009949"><span>Attributing <span class="hlt">Tropical</span> Cyclogenesis to Equatorial Waves in the Western North <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Schreck, Carl J., III; Molinari, John; Mohr, Karen I.</p> <p>2009-01-01</p> <p>The direct influences of equatorial waves on the genesis of <span class="hlt">tropical</span> cyclones are evaluated. <span class="hlt">Tropical</span> cyclogenesis is attributed to an equatorial wave when the filtered rainfall anomaly exceeds a threshold value at the genesis location. For an attribution threshold of 3 mm/day, 51% of warm season western North <span class="hlt">Pacific</span> <span class="hlt">tropical</span> cyclones are attributed to <span class="hlt">tropical</span> depression (TD)-type disturbances, 29% to equatorial Rossby waves, 26% to mixed Rossby-Gravity waves, 23% to Kelvin waves, 13% to the Madden-Julian oscillation (MJO), and 19% are not attributed to any equatorial wave. The fraction of <span class="hlt">tropical</span> cyclones attributed to TD-type disturbances is consistent with previous findings. Past studies have also demonstrated that the MJO significantly modulates <span class="hlt">tropical</span> cyclogenesis, but fewer storms are attributed to the MJO than any other wave type. This disparity arises from the difference between attribution and modulation. The MJO produces broad regions of favorable conditions for cyclogenesis, but the MJO alone might not determine when and where a storm will develop within these regions. <span class="hlt">Tropical</span> cyclones contribute less than 17% of the power in any portion of the equatorial wave spectrum because <span class="hlt">tropical</span> cyclones are relatively uncommon equatorward of 15deg latitude. In regions where they are active, however, <span class="hlt">tropical</span> cyclones can contribute more than 20% of the warm season rainfall and up to 50% of the total variance. <span class="hlt">Tropical</span> cyclone-related anomalies can significantly contaminate wave-filtered precipitation at the location of genesis. To mitigate this effect, the <span class="hlt">tropical</span> cyclone-related rainfall anomalies were removed before filtering in this study.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ClDy...49.2685P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ClDy...49.2685P"><span>Initialization shock in decadal hindcasts due to errors in wind stress over the <span class="hlt">tropical</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pohlmann, Holger; Kröger, Jürgen; Greatbatch, Richard J.; Müller, Wolfgang A.</p> <p>2017-10-01</p> <p>Low prediction skill in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> is a common problem in decadal prediction systems, especially for lead years 2-5 which, in many systems, is lower than in uninitialized experiments. On the other hand, the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> is of almost worldwide climate relevance through its teleconnections with other <span class="hlt">tropical</span> and extratropical regions and also of importance for global mean temperature. Understanding the causes of the reduced prediction skill is thus of major interest for decadal climate predictions. We look into the problem of reduced prediction skill by analyzing the Max Planck Institute Earth System Model (MPI-ESM) decadal hindcasts for the fifth phase of the Climate Model Intercomparison Project and performing a sensitivity experiment in which hindcasts are initialized from a model run forced only by surface wind stress. In both systems, sea surface temperature variability in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> is successfully initialized, but most skill is lost at lead years 2-5. Utilizing the sensitivity experiment enables us to pin down the reason for the reduced prediction skill in MPI-ESM to errors in wind stress used for the initialization. A spurious trend in the wind stress forcing displaces the equatorial thermocline in MPI-ESM unrealistically. When the climate model is then switched into its forecast mode, the recovery process triggers artificial El Niño and La Niña events at the surface. Our results demonstrate the importance of realistic wind stress products for the initialization of decadal predictions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3532504','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3532504"><span>What Maintains the <span class="hlt">Central</span> North <span class="hlt">Pacific</span> Genetic Discontinuity in <span class="hlt">Pacific</span> Herring?</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Liu, Ming; Lin, Longshan; Gao, Tianxiang; Yanagimoto, Takashi; Sakurai, Yasunori; Grant, W. Stewart</p> <p>2012-01-01</p> <p><span class="hlt">Pacific</span> herring show an abrupt genetic discontinuity in the <span class="hlt">central</span> North <span class="hlt">Pacific</span> that represents secondary contact between refuge populations previously isolated during Pleistocene glaciations. Paradoxically, high levels of gene flow produce genetic homogeneity among ocean-type populations within each group. Here, we surveyed variability in mtDNA control-region sequences (463 bp) and nine microsatellite loci in <span class="hlt">Pacific</span> herring from sites across the North <span class="hlt">Pacific</span> to further explore the nature of the genetic discontinuity around the Alaska Peninsula. Consistent with previous studies, little divergence (ΦST = 0.011) was detected between ocean-type populations of <span class="hlt">Pacific</span> herring in the North West <span class="hlt">Pacific</span>, except for a population in the Yellow Sea (ΦST = 0.065). A moderate reduction in genetic diversity for both mtDNA and microsatellites in the Yellow Sea likely reflects founder effects during the last colonization of this sea. Reciprocal monophyly between divergent mtDNA lineages (ΦST = 0.391) across the Alaska Peninsula defines the discontinuity across the North <span class="hlt">Pacific</span>. However, microsatellites did not show a strong break, as eastern Bering Sea (EBS) herring were more closely related to NE <span class="hlt">Pacific</span> than to NW <span class="hlt">Pacific</span> herring. This discordance between mtDNA and microsatellites may be due to microsatellite allelic convergence or to sex-biased dispersal across the secondary contact zone. The sharp discontinuity between <span class="hlt">Pacific</span> herring populations may be maintained by high-density blocking, competitive exclusion or hybrid inferiority. PMID:23300525</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMPP43A1441S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMPP43A1441S"><span>A speleothem record of South <span class="hlt">Pacific</span> Convergence Zone dynamics during MIS 3 - Evidence for non-stationary coupling between the southern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> and Greenland?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sinclair, D. J.; Sherrell, R. M.; Rowe, H. D.; Wright, J. D.; Mortlock, R. A.; Hellstrom, J. C.; Cheng, H.; Min, A.; Edwards, R. L.</p> <p>2014-12-01</p> <p>The South <span class="hlt">Pacific</span> Convergence Zone (SPCZ) is the largest component of the Intertropical Convergence Zone (ITCZ), and its impact on global climate rivals that of the deep convection at the heart of the Western <span class="hlt">Pacific</span> Warm Pool. Rapid glacial climate fluctuations, such as Dansgaard-Oeschger (D-O) Events, would have triggered a reorganization of <span class="hlt">tropical</span> systems such as the SPCZ, manifesting as significantly altered rainfall across the <span class="hlt">tropical</span> south <span class="hlt">Pacific</span>. However, a critical lack of high-resolution glacial records from this region means the dynamics of the SPCZ are largely unknown. We present a decade-resolution, absolute-dated speleothem rainfall record from the Island of Niue in the southern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> spanning 25-45 ka. Sr, Mg, δ18O and δ13C variations show that Niue experienced large, rapid fluctuations in rainfall lasting up to 1200 years. Between 40 and 45 ka, these show a remarkable concordance with the timing, duration and shape of D-O events 9-11. Rapid warming in Greenland was accompanied by a sudden increase in rainfall in Niue, implying that the SPCZ was strongly coupled with climate in the high Northern latitudes. These changes are not consistent with a wholesale northward shift in the SPCZ, which would have resulted in drying in Niue, and instead imply that the SPCZ underwent a more complex reorganization, perhaps rotating around its western edge in a manner analogous to modern-day extreme ENSO events. The speleothem record between 25-40 ka also shows large changes in rainfall, with D-O events identifiable. However, these changes are less well matched to Greenland, and include events not captured by the ice cores. It is clear that the SPCZ response to global climate change is complex: while it can closely couple with high-northern latitude climate for periods, this coupling may not be stationary with time. We speculate that this might result from changing precession, influencing which teleconnections dominate climate changes in the south</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70115060','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70115060"><span>Centennial changes in North <span class="hlt">Pacific</span> anoxia linked to <span class="hlt">tropical</span> trade winds</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Deutsch, Curtis; Berelson, William; Thunell, Robert; Weber, Thomas; Tems, Caitlin; McManus, James; Crusius, John; Ito, Taka; Baumgartner, Timothy; Ferreira, Vicente; Mey, Jacob; van Geen, Alexander</p> <p>2014-01-01</p> <p>Climate warming is expected to reduce oxygen (O2) supply to the ocean and expand its oxygen minimum zones (OMZs). We reconstructed variations in the extent of North <span class="hlt">Pacific</span> anoxia since 1850 using a geochemical proxy for denitrification (δ15N) from multiple sediment cores. Increasing δ15N since ~1990 records an expansion of anoxia, consistent with observed O2 trends. However, this was preceded by a longer declining δ15N trend that implies that the anoxic zone was shrinking for most of the 20th century. Both periods can be explained by changes in winds over the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> that drive upwelling, biological productivity, and O2 demand within the OMZ. If equatorial <span class="hlt">Pacific</span> winds resume their predicted weakening trend, the ocean’s largest anoxic zone will contract despite a global O2 decline.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120011243','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120011243"><span>The Effect of ENSO on Phytoplankton Composition in the <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rousseaux, Cecile</p> <p>2012-01-01</p> <p>The effect of climate variability on phytoplankton communities was assessed for the <span class="hlt">tropical</span> and sub-<span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean between 1998 and 2005 using an established biogeochemical assimilation model. The phytoplankton communities exhibited wide range of responses to climate variability, from radical shifts in the Equatorial <span class="hlt">Pacific</span>, to changes of only a couple of phytoplankton groups in the North <span class="hlt">Central</span> <span class="hlt">Pacific</span>, to no significant changes in the South <span class="hlt">Pacific</span>. In the Equatorial <span class="hlt">Pacific</span>, climate variability dominated the variability of phytoplankton. Here, nitrate, chlorophyll and all but one of the 4 phytoplankton types (diatoms, cyanobacteria and coccolithophores) were strongly correlated (p less than 0.01) with the Multivariate El Nino Southern Oscillation Index (MEI). In the North <span class="hlt">Central</span> <span class="hlt">Pacific</span>, MEI and chlorophyll were significantly (p<0.01) correlated along with two of the phytoplankton groups (chlorophytes and coccolithophores). Ocean biology in the South <span class="hlt">Pacific</span> was not significantly correlated with MEI. During La Ni a events, diatoms increased and expanded westward along the cold tongue (correlation with MEI, r=-0.81), while cyanobacteria concentrations decreased significantly (r=0.78). El Nino produced the reverse pattern, with cyanobacteria populations increasing while diatoms plummeted. The diverse response of phytoplankton in the different major basins of the <span class="hlt">Pacific</span> suggests the different roles climate variability can play in ocean biology.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_8 --> <div id="page_9" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="161"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ClDy..tmp...82G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ClDy..tmp...82G"><span>Effect of boreal spring precipitation anomaly pattern change in the late 1990s over <span class="hlt">tropical</span> <span class="hlt">Pacific</span> on the atmospheric teleconnection</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Guo, Yuanyuan; Wen, Zhiping; Chen, Ruidan; Li, Xiuzhen; Yang, Xiu-Qun</p> <p>2018-02-01</p> <p>Observational evidence showed that the leading mode of precipitation variability over the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> during boreal spring experienced a pronounced interdecadal change around the late 1990s, characterized by a precipitation pattern shift from an eastern <span class="hlt">Pacific</span> (EP) type to a <span class="hlt">central</span> <span class="hlt">Pacific</span> (CP) type. The distinct impacts of such a precipitation pattern shift on the extratropical atmospheric teleconnection were examined. An apparent poleward teleconnection extending from the <span class="hlt">tropics</span> to the North Atlantic region was observed after 1998, while, there was no significant teleconnection before 1998. To understand why only the CP-type precipitation mode is associated with a striking atmospheric teleconnection after 1998, diagnostic analyses with the Eliassen-Palm flux and Rossby wave source (RWS) based on the barotropic vorticity equation were performed. The results show that for the EP-type precipitation mode, no significant RWS anomalies appeared over the subtropical <span class="hlt">Pacific</span> due to the opposite effect of the vortex stretching and absolute vorticity advection processes. For the CP-type precipitation mode, however, there are both significant vorticity forcing source over the subtropical CP and clear poleward-propagation of Rossby wave. The spatial distribution of the CP-type precipitation pattern tends to excite a conspicuous anomalous southerly and a well-organized negative vorticity center over the subtropical CP where both the mean absolute vorticity gradient and mean divergence flow are large, hence, the interaction between the heating-induced anomalous circulation and the basic state made the generation of Rossby waves conceivable and effective. Such corresponding teleconnection responses to the prescribed heating were also examined by using a Linear Baroclinic Model (LBM). It turned out that significant poleward teleconnection pattern is only caused by the CP-type precipitation mode, rather than by the EP-type precipitation mode. Further sensitive experiments</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15.1295V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15.1295V"><span>Paleoenvironments, Evolution, and Geomicrobiology in a <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Lake: The Lake Towuti Drilling Project (TOWUTI)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vogel, Hendrik; Russell, James M.; Bijaksana, Satria; Fowle, David; von Rintelen, Thomas; Stevenson, Janelle; Watkinson, Ian; Marwoto, Ristiyanti; Melles, Martin; Crowe, Sean; Haffner, Doug; King, John</p> <p>2013-04-01</p> <p>Lake Towuti (2.5°S, 121°E) is a, 560 km2, 200-m deep tectonic lake at the downstream end of the Malili lake system, a set of five, ancient (1-2 MYr) tectonic lakes in <span class="hlt">central</span> Sulawesi, Indonesia. Lake Towuti's location in <span class="hlt">central</span> Indonesia provides a unique opportunity to reconstruct long-term paleoclimate change in a crucially important yet understudied region- the <span class="hlt">tropical</span> Western <span class="hlt">Pacific</span> warm pool, heart of the El Niño-Southern Oscillation. The Malili Lakes have extraordinarily high rates of floral and faunal endemism, and the lakes are surrounded by one of the most diverse <span class="hlt">tropical</span> forests on Earth. Drilling in Lake Towuti will identify the age and origin of the lake and the environmental and climatic context that shaped the evolution of this unique lacustrine and terrestrial ecosystem. The ultramafic (ophiolitic) rocks and lateritic soils surrounding Lake Towuti provide metal substrates that feed a diverse, exotic microbial community, analogous to the microbial ecosystems that operated in the Archean Oceans. Drill core will provide unique insight into long-term changes in this ecosystem, as well as microbial processes operating at depth in the sediment column. While the Malili Lakes have long been considered high-priority drilling sites, only now do we have the requisite site survey information to propose the development of ICDP's first lake drilling target in the <span class="hlt">tropical</span> western <span class="hlt">Pacific</span>. High-resolution seismic reflection data (CHIRP and airgun) combined with numerous long sediment piston cores collected from 2007-2010 demonstrate the enormous promise of Lake Towuti for an ICDP drilling campaign. Well-stratified sequences of up to 150 m thickness, uninterrupted by unconformities or erosional truncation, are present in multiple sub-basins within Towuti, providing ideal sites for long-term environmental, climatic, and limnological reconstructions. Multiproxy analyses of our piston cores document a continuous and detailed record of moisture balance</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRD..122.9721N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRD..122.9721N"><span>Western North <span class="hlt">Pacific</span> <span class="hlt">Tropical</span> Cyclone Model Tracks in Present and Future Climates</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nakamura, Jennifer; Camargo, Suzana J.; Sobel, Adam H.; Henderson, Naomi; Emanuel, Kerry A.; Kumar, Arun; LaRow, Timothy E.; Murakami, Hiroyuki; Roberts, Malcolm J.; Scoccimarro, Enrico; Vidale, Pier Luigi; Wang, Hui; Wehner, Michael F.; Zhao, Ming</p> <p>2017-09-01</p> <p>Western North <span class="hlt">Pacific</span> <span class="hlt">tropical</span> cyclone (TC) model tracks are analyzed in two large multimodel ensembles, spanning a large variety of models and multiple future climate scenarios. Two methodologies are used to synthesize the properties of TC tracks in this large data set: cluster analysis and mass moment ellipses. First, the models' TC tracks are compared to observed TC tracks' characteristics, and a subset of the models is chosen for analysis, based on the tracks' similarity to observations and sample size. Potential changes in track types in a warming climate are identified by comparing the kernel smoothed probability distributions of various track variables in historical and future scenarios using a Kolmogorov-Smirnov significance test. Two track changes are identified. The first is a statistically significant increase in the north-south expansion, which can also be viewed as a poleward shift, as TC tracks are prevented from expanding equatorward due to the weak Coriolis force near the equator. The second change is an eastward shift in the storm tracks that occur near the <span class="hlt">central</span> <span class="hlt">Pacific</span> in one of the multimodel ensembles, indicating a possible increase in the occurrence of storms near Hawaii in a warming climate. The dependence of the results on which model and future scenario are considered emphasizes the necessity of including multiple models and scenarios when considering future changes in TC characteristics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.A51E3082C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.A51E3082C"><span>Shallow cloud statistics over <span class="hlt">Tropical</span> Western <span class="hlt">Pacific</span>: CAM5 versus ARM Comparison</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chandra, A.; Zhang, C.; Klein, S. A.; Ma, H. Y.; Kollias, P.; Xie, S.</p> <p>2014-12-01</p> <p>The role of shallow convection in the <span class="hlt">tropical</span> convective cloud life cycle has received increasing interest because of its sensitivity to simulate large-scale <span class="hlt">tropical</span> disturbances such as MJO. Though previous studies have proposed several hypotheses to explain the role of shallow clouds in the convective life cycle, our understanding on the role of shallow clouds is still premature. There are more questions needs to be addressed related to the role of different cloud population, conditions favorable for shallow to deep convection transitions, and their characteristics at different stages of the convective cloud life. The present study aims to improve the understanding of the shallow clouds by documenting the role of different shallow cloud population for the Year of <span class="hlt">Tropical</span> Convection period using Atmospheric Radiation Measurement observations at the <span class="hlt">Tropical</span> Western <span class="hlt">Pacific</span> Manus site. The performance of the CAM5 model to simulate shallow clouds are tested using observed cloud statistics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20120010547&hterms=WTP&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DWTP','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20120010547&hterms=WTP&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DWTP"><span>El Nino-Southern Oscillation Correlated Aerosol Angstrom Exponent Anomaly Over the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Discovered in Satellite Measurements</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Li, Jing; Carlson, Barbara E.; Lacis, Andrew A.</p> <p>2011-01-01</p> <p>El Nino.Southern Oscillation (ENSO) is the dominant mode of interannual variability in the <span class="hlt">tropical</span> atmosphere. ENSO could potentially impact local and global aerosol properties through atmospheric circulation anomalies and teleconnections. By analyzing aerosol properties, including aerosol optical depth (AOD) and Angstrom exponent (AE; often used as a qualitative indicator of aerosol particle size) from the Moderate Resolution Imaging Spectrometer, the Multiangle Imaging Spectroradiometer and the Sea ]viewing Wide Field ]of ]view Sensor for the period 2000.2011, we find a strong correlation between the AE data and the multivariate ENSO index (MEI) over the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. Over the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> (WTP), AE increases during El Nino events and decreases during La Nina events, while the opposite is true over the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> (ETP). The difference between AE anomalies in the WTP and ETP has a higher correlation coefficient (>0.7) with the MEI than the individual time series and could be considered another type of ENSO index. As no significant ENSO correlation is found in AOD over the same region, the change in AE (and hence aerosol size) is likely to be associated with aerosol composition changes due to anomalous meteorological conditions induced by the ENSO. Several physical parameters or mechanisms that might be responsible for the correlation are discussed. Preliminary analysis indicates surface wind anomaly might be the major contributor, as it reduces sea ]salt production and aerosol transport during El Nino events. Precipitation and cloud fraction are also found to be correlated with <span class="hlt">tropical</span> <span class="hlt">Pacific</span> AE. Possible mechanisms, including wet removal and cloud shielding effects, are considered. Variations in relative humidity, tropospheric ozone concentration, and ocean color during El Nino have been ruled out. Further investigation is needed to fully understand this AE ]ENSO covariability and the underlying physical processes responsible for</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017Chaos..27l6704S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017Chaos..27l6704S"><span>Role of atmosphere-ocean interactions in supermodeling the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> climate</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shen, Mao-Lin; Keenlyside, Noel; Bhatt, Bhuwan C.; Duane, Gregory S.</p> <p>2017-12-01</p> <p>The supermodel strategy interactively combines several models to outperform the individual models comprising it. A key advantage of the approach is that nonlinear improvements can be achieved, in contrast to the linear weighted combination of individual unconnected models. This property is found in a climate supermodel constructed by coupling two versions of an atmospheric model differing only in their convection scheme to a single ocean model. The ocean model receives a weighted combination of the momentum and heat fluxes. Optimal weights can produce a supermodel with a basic state similar to observations: a single Intertropical Convergence zone (ITCZ), with a western <span class="hlt">Pacific</span> warm pool and an equatorial cold tongue. This is in stark contrast to the erroneous double ITCZ pattern simulated by both of the two stand-alone coupled models. By varying weights, we develop a conceptual scheme to explain how combining the momentum fluxes of the two different atmospheric models affects equatorial upwelling and surface wind feedback so as to give a realistic basic state in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. In particular, we propose a mechanism based on the competing influences of equatorial zonal wind and off-equatorial wind stress curl in driving equatorial upwelling in the coupled models. Our results show how nonlinear ocean-atmosphere interaction is essential in combining these two effects to build different sea surface temperature structures, some of which are realistic. They also provide some insight into observed and modelled <span class="hlt">tropical</span> <span class="hlt">Pacific</span> climate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29289039','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29289039"><span>Role of atmosphere-ocean interactions in supermodeling the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> climate.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Shen, Mao-Lin; Keenlyside, Noel; Bhatt, Bhuwan C; Duane, Gregory S</p> <p>2017-12-01</p> <p>The supermodel strategy interactively combines several models to outperform the individual models comprising it. A key advantage of the approach is that nonlinear improvements can be achieved, in contrast to the linear weighted combination of individual unconnected models. This property is found in a climate supermodel constructed by coupling two versions of an atmospheric model differing only in their convection scheme to a single ocean model. The ocean model receives a weighted combination of the momentum and heat fluxes. Optimal weights can produce a supermodel with a basic state similar to observations: a single Intertropical Convergence zone (ITCZ), with a western <span class="hlt">Pacific</span> warm pool and an equatorial cold tongue. This is in stark contrast to the erroneous double ITCZ pattern simulated by both of the two stand-alone coupled models. By varying weights, we develop a conceptual scheme to explain how combining the momentum fluxes of the two different atmospheric models affects equatorial upwelling and surface wind feedback so as to give a realistic basic state in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. In particular, we propose a mechanism based on the competing influences of equatorial zonal wind and off-equatorial wind stress curl in driving equatorial upwelling in the coupled models. Our results show how nonlinear ocean-atmosphere interaction is essential in combining these two effects to build different sea surface temperature structures, some of which are realistic. They also provide some insight into observed and modelled <span class="hlt">tropical</span> <span class="hlt">Pacific</span> climate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018E%26SS....5...50L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018E%26SS....5...50L"><span>The Impacts of Bias in Cloud-Radiation-Dynamics Interactions on <span class="hlt">Central</span> <span class="hlt">Pacific</span> Seasonal and El Niño Simulations in Contemporary GCMs</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, J.-L. F.; Suhas, E.; Richardson, Mark; Lee, Wei-Liang; Wang, Yi-Hui; Yu, Jia-Yuh; Lee, Tong; Fetzer, Eric; Stephens, Graeme; Shen, Min-Hua</p> <p>2018-02-01</p> <p>Most of the global climate models (GCMs) in the Coupled Model Intercomparison Project, phase 5 do not include precipitating ice (aka falling snow) in their radiation calculations. We examine the importance of the radiative effects of precipitating ice on simulated surface wind stress and sea surface temperatures (SSTs) in terms of seasonal variation and in the evolution of <span class="hlt">central</span> <span class="hlt">Pacific</span> El Niño (CP-El Niño) events. Using controlled simulations with the CESM1 model, we show that the exclusion of precipitating ice radiative effects generates a persistent excessive upper-level radiative cooling and an increasingly unstable atmosphere over convective regions such as the western <span class="hlt">Pacific</span> and <span class="hlt">tropical</span> convergence zones. The invigorated convection leads to persistent anomalous low-level outflows which weaken the easterly trade winds, reducing upper-ocean mixing and leading to a positive SST bias in the model mean state. In CP-El Niño events, this means that outflow from the modeled convection in the <span class="hlt">central</span> <span class="hlt">Pacific</span> reduces winds to the east, allowing unrealistic eastward propagation of warm SST anomalies following the peak in CP-El Niño activity. Including the radiative effects of precipitating ice reduces these model biases and improves the simulated life cycle of the CP-El Niño. Improved simulations of present-day <span class="hlt">tropical</span> seasonal variations and CP-El Niño events would increase the confidence in simulating their future behavior.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3574161','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3574161"><span>Habitat Availability and Heterogeneity and the Indo-<span class="hlt">Pacific</span> Warm Pool as Predictors of Marine Species Richness in the <span class="hlt">Tropical</span> Indo-<span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Sanciangco, Jonnell C.; Carpenter, Kent E.; Etnoyer, Peter J.; Moretzsohn, Fabio</p> <p>2013-01-01</p> <p>Range overlap patterns were observed in a dataset of 10,446 expert-derived marine species distribution maps, including 8,295 coastal fishes, 1,212 invertebrates (crustaceans and molluscs), 820 reef-building corals, 50 seagrasses, and 69 mangroves. Distributions of <span class="hlt">tropical</span> Indo-<span class="hlt">Pacific</span> shore fishes revealed a concentration of species richness in the northern apex and <span class="hlt">central</span> region of the Coral Triangle epicenter of marine biodiversity. This pattern was supported by distributions of invertebrates and habitat-forming primary producers. Habitat availability, heterogeneity, and sea surface temperatures were highly correlated with species richness across spatial grains ranging from 23,000 to 5,100,000 km2 with and without correction for autocorrelation. The consistent retention of habitat variables in our predictive models supports the area of refuge hypothesis which posits reduced extinction rates in the Coral Triangle. This does not preclude support for a center of origin hypothesis that suggests increased speciation in the region may contribute to species richness. In addition, consistent retention of sea surface temperatures in models suggests that available kinetic energy may also be an important factor in shaping patterns of marine species richness. Kinetic energy may hasten rates of both extinction and speciation. The position of the Indo-<span class="hlt">Pacific</span> Warm Pool to the east of the Coral Triangle in <span class="hlt">central</span> Oceania and a pattern of increasing species richness from this region into the <span class="hlt">central</span> and northern parts of the Coral Triangle suggests peripheral speciation with enhanced survival in the cooler parts of the Coral Triangle that also have highly concentrated available habitat. These results indicate that conservation of habitat availability and heterogeneity is important to reduce extinction of marine species and that changes in sea surface temperatures may influence the evolutionary potential of the region. PMID:23457533</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23457533','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23457533"><span>Habitat availability and heterogeneity and the indo-<span class="hlt">pacific</span> warm pool as predictors of marine species richness in the <span class="hlt">tropical</span> Indo-<span class="hlt">Pacific</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Sanciangco, Jonnell C; Carpenter, Kent E; Etnoyer, Peter J; Moretzsohn, Fabio</p> <p>2013-01-01</p> <p>Range overlap patterns were observed in a dataset of 10,446 expert-derived marine species distribution maps, including 8,295 coastal fishes, 1,212 invertebrates (crustaceans and molluscs), 820 reef-building corals, 50 seagrasses, and 69 mangroves. Distributions of <span class="hlt">tropical</span> Indo-<span class="hlt">Pacific</span> shore fishes revealed a concentration of species richness in the northern apex and <span class="hlt">central</span> region of the Coral Triangle epicenter of marine biodiversity. This pattern was supported by distributions of invertebrates and habitat-forming primary producers. Habitat availability, heterogeneity, and sea surface temperatures were highly correlated with species richness across spatial grains ranging from 23,000 to 5,100,000 km(2) with and without correction for autocorrelation. The consistent retention of habitat variables in our predictive models supports the area of refuge hypothesis which posits reduced extinction rates in the Coral Triangle. This does not preclude support for a center of origin hypothesis that suggests increased speciation in the region may contribute to species richness. In addition, consistent retention of sea surface temperatures in models suggests that available kinetic energy may also be an important factor in shaping patterns of marine species richness. Kinetic energy may hasten rates of both extinction and speciation. The position of the Indo-<span class="hlt">Pacific</span> Warm Pool to the east of the Coral Triangle in <span class="hlt">central</span> Oceania and a pattern of increasing species richness from this region into the <span class="hlt">central</span> and northern parts of the Coral Triangle suggests peripheral speciation with enhanced survival in the cooler parts of the Coral Triangle that also have highly concentrated available habitat. These results indicate that conservation of habitat availability and heterogeneity is important to reduce extinction of marine species and that changes in sea surface temperatures may influence the evolutionary potential of the region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.C54A..08S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.C54A..08S"><span><span class="hlt">Tropical</span> pacing of Antarctic sea ice increase</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schneider, D. P.</p> <p>2015-12-01</p> <p>One reason why coupled climate model simulations generally do not reproduce the observed increase in Antarctic sea ice extent may be that their internally generated climate variability does not sync with the observed phases of phenomena like the <span class="hlt">Pacific</span> Decadal Oscillation (PDO) and ENSO. For example, it is unlikely for a free-running coupled model simulation to capture the shift of the PDO from its positive to negative phase during 1998, and the subsequent ~15 year duration of the negative PDO phase. In previously presented work based on atmospheric models forced by observed <span class="hlt">tropical</span> SSTs and stratospheric ozone, we demonstrated that <span class="hlt">tropical</span> variability is key to explaining the wind trends over the Southern Ocean during the past ~35 years, particularly in the Ross, Amundsen and Bellingshausen Seas, the regions of the largest trends in sea ice extent and ice season duration. Here, we extend this idea to coupled model simulations with the Community Earth System Model (CESM) in which the evolution of SST anomalies in the <span class="hlt">central</span> and eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> is constrained to match the observations. This ensemble of 10 "<span class="hlt">tropical</span> pacemaker" simulations shows a more realistic evolution of Antarctic sea ice anomalies than does its unconstrained counterpart, the CESM Large Ensemble (both sets of runs include stratospheric ozone depletion and other time-dependent radiative forcings). In particular, the pacemaker runs show that increased sea ice in the eastern Ross Sea is associated with a deeper Amundsen Sea Low (ASL) and stronger westerlies over the south <span class="hlt">Pacific</span>. These circulation patterns in turn are linked with the negative phase of the PDO, characterized by negative SST anomalies in the <span class="hlt">central</span> and eastern <span class="hlt">Pacific</span>. The timing of <span class="hlt">tropical</span> decadal variability with respect to ozone depletion further suggests a strong role for <span class="hlt">tropical</span> variability in the recent acceleration of the Antarctic sea ice trend, as ozone depletion stabilized by late 1990s, prior to the most</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1409983-low-cloud-characteristics-over-tropical-western-pacific-from-arm-observations-cam5-simulations','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1409983-low-cloud-characteristics-over-tropical-western-pacific-from-arm-observations-cam5-simulations"><span>Low-cloud characteristics over the <span class="hlt">tropical</span> western <span class="hlt">Pacific</span> from ARM observations and CAM5 simulations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Chandra, Arunchandra S.; Zhang, Chidong; Klein, Stephen A.; ...</p> <p>2015-09-10</p> <p>Here, this study evaluates the ability of the Community Atmospheric Model version 5 (CAM5) to reproduce low clouds observed by the Atmospheric Radiation Measurement (ARM) cloud radar at Manus Island of the <span class="hlt">tropical</span> western <span class="hlt">Pacific</span> during the Years of <span class="hlt">Tropical</span> Convection. Here low clouds are defined as clouds with their tops below the freezing level and bases within the boundary layer. Low-cloud statistics in CAM5 simulations and ARM observations are compared in terms of their general occurrence, mean vertical profiles, fraction of precipitating versus nonprecipitating events, diurnal cycle, and monthly time series. Other types of clouds are included to putmore » the comparison in a broader context. The comparison shows that the model overproduces total clouds and their precipitation fraction but underestimates low clouds in general. The model, however, produces excessive low clouds in a thin layer between 954 and 930 hPa, which coincides with excessive humidity near the top of the mixed layer. This suggests that the erroneously excessive low clouds stem from parameterization of both cloud and turbulence mixing. The model also fails to produce the observed diurnal cycle in low clouds, not exclusively due to the model coarse grid spacing that does not resolve Manus Island. Lastly, this study demonstrates the utility of ARM long-term cloud observations in the <span class="hlt">tropical</span> western <span class="hlt">Pacific</span> in verifying low clouds simulated by global climate models, illustrates issues of using ARM observations in model validation, and provides an example of severe model biases in producing observed low clouds in the <span class="hlt">tropical</span> western <span class="hlt">Pacific</span>.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4889992','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4889992"><span>Vertical distribution of Eucalanoid copepods within the Costa Rica Dome area of the Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Jackson, Melanie L.; Smith, Sharon L.</p> <p>2016-01-01</p> <p>A variety of ecological strategies for tolerance of low-oxygen conditions within the Costa Rica Dome (CRD) area of the Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> are documented for the copepod family Eucalanidae. During the summer of 2010, we compared the ecological strategies used by the Eucalanidae inside and outside the <span class="hlt">central</span> CRD region. We compared the vertical and horizontal distributions of five species, Eucalanus inermis, Subeucalanus subtenuis, Subeucalanus subcrassus, Subeucalanus pileatus and Pareucalanus attenuatus together with Rhincalanus species, in the epipelagic (upper 200 m) among four locations, which we grouped into a section roughly crossing the core CRD area (inside–outside core CRD). The coastal area outside the CRD supported the most diverse assemblage, whereas overall abundance of Eucalanidae in the <span class="hlt">central</span> CRD was 2-fold greater than outside and dominated by E. inermis (>60%). Eucalanidae in the <span class="hlt">central</span> CRD had a shallow depth distribution, closely associated with the shallow thermocline (10–20 m). There was no evidence of daily vertical migration in the <span class="hlt">central</span> CRD, but E. inermis demonstrated vertical migration outside the CRD. The vertical abundance patterns of Eucalanidae in the CRD region reflect complex interactions between subtle physical–chemical differences and food resources. PMID:27275032</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20160013888&hterms=eastern+western&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Deastern%2Bwestern%26Nf%3DPublication-Date%257CBTWN%2B20070101%2B20180604','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20160013888&hterms=eastern+western&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Deastern%2Bwestern%26Nf%3DPublication-Date%257CBTWN%2B20070101%2B20180604"><span>An Assessment of Multimodel Simulations for the Variability of Western North <span class="hlt">Pacific</span> <span class="hlt">Tropical</span> Cyclones and Its Association with ENSO</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Han, Rongqing; Wang, Hui; Hu, Zeng-Zhen; Kumar, Arun; Li, Weijing; Long, Lindsey N.; Schemm, Jae-Kyung E.; Peng, Peitao; Wang, Wanqiu; Si, Dong; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20160013888'); toggleEditAbsImage('author_20160013888_show'); toggleEditAbsImage('author_20160013888_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20160013888_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20160013888_hide"></p> <p>2016-01-01</p> <p>An assessment of simulations of the interannual variability of <span class="hlt">tropical</span> cyclones (TCs) over the western North <span class="hlt">Pacific</span> (WNP) and its association with El Niño-Southern Oscillation (ENSO), as well as a subsequent diagnosis for possible causes of model biases generated from simulated large-scale climate conditions, are documented in the paper. The model experiments are carried out by the Hurricane Work Group under the U.S. Climate Variability and Predictability Research Program (CLIVAR) using five global climate models (GCMs) with a total of 16 ensemble members forced by the observed sea surface temperature and spanning the 28-yr period from 1982 to 2009. The results show GISS and GFDL model ensemble means best simulate the interannual variability of TCs, and the multimodel ensemble mean (MME) follows. Also, the MME has the closest climate mean annual number of WNP TCs and the smallest root-mean-square error to the observation. Most GCMs can simulate the interannual variability of WNP TCs well, with stronger TC activities during two types of El Niño-namely, eastern <span class="hlt">Pacific</span> (EP) and <span class="hlt">central</span> <span class="hlt">Pacific</span> (CP) El Niño-and weaker activity during La Niña. However, none of the models capture the differences in TC activity between EP and CP El Niño as are shown in observations. The inability of models to distinguish the differences in TC activities between the two types of El Niño events may be due to the bias of the models in response to the shift of <span class="hlt">tropical</span> heating associated with CP El Niño.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018GeoRL..45.1981J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018GeoRL..45.1981J"><span>Northern Galápagos Corals Reveal Twentieth Century Warming in the Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jimenez, Gloria; Cole, Julia E.; Thompson, Diane M.; Tudhope, Alexander W.</p> <p>2018-02-01</p> <p>Models and observations disagree regarding sea surface temperature (SST) trends in the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. We present a new Sr/Ca-SST record that spans 1940-2010 from two Wolf Island corals (northern Galápagos). Trend analysis of the Wolf record shows significant warming on multiple timescales, which is also present in several other records and gridded instrumental products. Together, these data sets suggest that most of the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> has warmed over the twentieth century. In contrast, recent decades have been characterized by warming during boreal spring and summer (especially north of the equator), and subtropical cooling during boreal fall and winter (especially south of the equator). These SST trends are consistent with the effects of radiative forcing, mitigated by cooling due to wind forcing during boreal winter, as well as intensified upwelling and a strengthened Equatorial Undercurrent.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20170005228','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20170005228"><span>The NASA Airborne <span class="hlt">Tropical</span> TRopopause EXperiment (ATTREX): High-Altitude Aircraft Measurements in the <span class="hlt">Tropical</span> Western <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Jensen, Eric J.; Pfister, Leonhard; Jordan, David E.; Bui, Thaopaul V.; Ueyama, Rei; Singh, Hanwant B.; Thornberry, Troy; Rollins, Andrew W.; Gao, Ru-Shan; Fahey, David W.; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20170005228'); toggleEditAbsImage('author_20170005228_show'); toggleEditAbsImage('author_20170005228_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20170005228_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20170005228_hide"></p> <p>2017-01-01</p> <p>The February through March 2014 deployment of the NASA Airborne <span class="hlt">Tropical</span> TRopopause EXperiment (ATTREX) provided unique in situ measurements in the western <span class="hlt">Pacific</span> <span class="hlt">Tropical</span> Tropopause Layer (TTL). Six flights were conducted from Guam with the long-range, high-altitude, unmanned Global Hawk aircraft. The ATTREX Global Hawk payload provided measurements of water vapor, meteorological conditions, cloud properties, tracer and chemical radical concentrations, and radiative fluxes. The campaign was partially coincident with the CONTRAST and CAST airborne campaigns based in Guam using lower-altitude aircraft (see companion articles in this issue). The ATTREX dataset is being used for investigations of TTL cloud, transport, dynamical, and chemical processes as well as for evaluation and improvement of global-model representations of TTL processes. The ATTREX data is openly available at https:espoarchive.nasa.gov.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70026470','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70026470"><span>Comparison of natural resource issues on <span class="hlt">tropical</span> <span class="hlt">pacific</span> ranges</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Helweg, D.A.; Jacobi, J.D.</p> <p>2004-01-01</p> <p>The natural resources issues on <span class="hlt">tropical</span> <span class="hlt">Pacific</span> ranges are compared. If active management plan is in place, FWS may exempt those spp. from critical Habitat Prevention and control or invasive species essential. Wetlands are low-hanging fruit for restoration, but birds present mgmt. challenge. Marine sites may offer less potential for precise mgmt. of natural resources than terrestrial sites such as, lack of knowledge, observational limits, ecosystem complexity, mobile biota. It has been suggested that the tremendus public interest in helping with conservation activities - volunteer opportunities may offset staffing shortfalls.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/7212812-thermal-tolerance-tropical-versus-subtropical-pacific-reef-corals','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/7212812-thermal-tolerance-tropical-versus-subtropical-pacific-reef-corals"><span>Thermal tolerance in <span class="hlt">tropical</span> versus subtropical <span class="hlt">Pacific</span> reef corals</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Coles, S.L.; Jokiel, P.L.; Lewis, C.R.</p> <p>1976-04-01</p> <p>Upper lethal temperature tolerances of reef corals in Hawaii and at Enewetak, Marshall Islands, were determined in the field and under controlled laboratory conditions. Enewetak corals survived in situ temperatures of nearly 34/sup 0/C, whereas 32/sup 0/C was lethal to Hawaiian corals for similar short-term exposures. Laboratory determinations indicate that the upper thermal limits of Hawaiian corals are approximately 2/sup 0/C less than congeners from the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. Differences in coral thermal tolerances correspond to differences in the ambient temperature patterns between geographic areas.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ClDy..tmp..748C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ClDy..tmp..748C"><span><span class="hlt">Pacific</span>-North American teleconnection and North <span class="hlt">Pacific</span> Oscillation: historical simulation and future projection in CMIP5 models</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Zheng; Gan, Bolan; Wu, Lixin; Jia, Fan</p> <p>2017-09-01</p> <p>Based on reanalysis datasets and as many as 35 CMIP5 models, this study evaluates the capability of climate models to simulate the spatiotemporal features of <span class="hlt">Pacific</span>-North American teleconnection (PNA) and North <span class="hlt">Pacific</span> Oscillation (NPO) in the twentieth century wintertime, and further investigates their responses to greenhouse warming in the twenty-first century. Analysis reveals that while the majority (80%) of models reasonably simulate either the geographical distribution or the amplitude of PNA/NPO pattern, only half of models can well capture both features in space. As for the temporal features, variabilities of PNA and NPO in most models are biased toward higher amplitude. Additionally, most models simulate the interannual variabilities of PNA and NPO, qualitatively consistent with the observation, whereas models generally lack the capability to reproduce the decadal (20-25 years) variability of PNA. As the climate warms under the strongest future warming scenario, the PNA intensity is found to be strengthened, whereas there is no consensus on the direction of change in the NPO intensity among models. The intensification of positive PNA is primarily manifested in the large deepening of the North <span class="hlt">Pacific</span> trough, which is robust as it is 2.3 times the unforced internal variability. By focusing on the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean, we find that the multidecadal evolution of the North <span class="hlt">Pacific</span> trough intensity (dominating the PNA intensity evolution) is closely related to that of the analogous trough in the PNA-like teleconnection forced by sea surface temperature anomalies (SSTa) in the <span class="hlt">tropical</span> <span class="hlt">central</span> <span class="hlt">Pacific</span> (CP) rather than the <span class="hlt">tropical</span> eastern <span class="hlt">Pacific</span> (EP). Such association is also found to act under greenhouse warming: that is, the strengthening of the PNA-like teleconnection induced by the CP SSTa rather than the EP SSTa is a driving force for the intensification of PNA. This is in part owing to the robust enhancement of the <span class="hlt">tropical</span> precipitation response to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ClDy...50.4379C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ClDy...50.4379C"><span><span class="hlt">Pacific</span>-North American teleconnection and North <span class="hlt">Pacific</span> Oscillation: historical simulation and future projection in CMIP5 models</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Zheng; Gan, Bolan; Wu, Lixin; Jia, Fan</p> <p>2018-06-01</p> <p>Based on reanalysis datasets and as many as 35 CMIP5 models, this study evaluates the capability of climate models to simulate the spatiotemporal features of <span class="hlt">Pacific</span>-North American teleconnection (PNA) and North <span class="hlt">Pacific</span> Oscillation (NPO) in the twentieth century wintertime, and further investigates their responses to greenhouse warming in the twenty-first century. Analysis reveals that while the majority (80%) of models reasonably simulate either the geographical distribution or the amplitude of PNA/NPO pattern, only half of models can well capture both features in space. As for the temporal features, variabilities of PNA and NPO in most models are biased toward higher amplitude. Additionally, most models simulate the interannual variabilities of PNA and NPO, qualitatively consistent with the observation, whereas models generally lack the capability to reproduce the decadal (20-25 years) variability of PNA. As the climate warms under the strongest future warming scenario, the PNA intensity is found to be strengthened, whereas there is no consensus on the direction of change in the NPO intensity among models. The intensification of positive PNA is primarily manifested in the large deepening of the North <span class="hlt">Pacific</span> trough, which is robust as it is 2.3 times the unforced internal variability. By focusing on the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean, we find that the multidecadal evolution of the North <span class="hlt">Pacific</span> trough intensity (dominating the PNA intensity evolution) is closely related to that of the analogous trough in the PNA-like teleconnection forced by sea surface temperature anomalies (SSTa) in the <span class="hlt">tropical</span> <span class="hlt">central</span> <span class="hlt">Pacific</span> (CP) rather than the <span class="hlt">tropical</span> eastern <span class="hlt">Pacific</span> (EP). Such association is also found to act under greenhouse warming: that is, the strengthening of the PNA-like teleconnection induced by the CP SSTa rather than the EP SSTa is a driving force for the intensification of PNA. This is in part owing to the robust enhancement of the <span class="hlt">tropical</span> precipitation response to</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_9 --> <div id="page_10" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="181"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006PrOce..69..318F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006PrOce..69..318F"><span>Zooplankton and the oceanography of the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span>: A review</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fernández-Álamo, María Ana; Färber-Lorda, Jaime</p> <p>2006-05-01</p> <p>We review the spatial and temporal patterns of zooplankton in the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean and relationships with oceanographic factors that affect zooplankton distribution, abundance and trophic relationships. Large-scale spatial patterns of some zooplankton groups show broad coincidence with surface water masses, circulation, and upwelling regions, in agreement with an ecological and dynamic partitioning of the pelagic ecosystem. The papers reviewed and a new compilation of zooplankton volume data at large-scale show that abundance patterns of zooplankton biomass have their highest values in the upwelling regions, including the Gulf of Tehuantepec, the Costa Rica Dome, the equatorial cold tongue, and the coast of Peru. Some of the first studies of zooplankton vertical distribution were done in this region, and a general review of the topic is presented. The possible physiological implications of vertical migration in zooplankton and the main hypotheses are described, with remarks on the importance of the oxygen minimum zone (OMZ) as a barrier to both the vertical distribution and migration of zooplankton in the region. Recent results, using multiple-net gear, show that vertical distribution is more complex than previously thought. There are some well-adapted species that do live and migrate within the OMZ. Temporal patterns are reviewed and summarized with historical data. Seasonal variations in zooplankton biomass follow productivity cycles in upwelling areas. No zooplankton time series exist to resolve ENSO effects in oceanic regions, but some El Niño events have had effects in the Peru Current ecosystem. Multidecadal periods of up to 50 years show a shift from a warm sardine regime with a low zooplankton biomass to a cool anchovy regime in the eastern <span class="hlt">Pacific</span> with higher zooplankton biomasses. However, zooplankton volume off Peru has remained at low values since the 1972 El Niño, a trend opposite to that of anchoveta biomass since 1984. Studies of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ClDy..tmp..325S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ClDy..tmp..325S"><span>A spurious warming trend in the NMME equatorial <span class="hlt">Pacific</span> SST hindcasts</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shin, Chul-Su; Huang, Bohua</p> <p>2017-06-01</p> <p>Using seasonal hindcasts of six different models participating in the North American Multimodel Ensemble project, the trend of the predicted sea surface temperature (SST) in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> for 1982-2014 at each lead month and its temporal evolution with respect to the lead month are investigated for all individual models. Since the coupled models are initialized with the observed ocean, atmosphere, land states from observation-based reanalysis, some of them using their own data assimilation process, one would expect that the observed SST trend is reasonably well captured in their seasonal predictions. However, although the observed SST features a weak-cooling trend for the 33-year period with La Niña-like spatial pattern in the <span class="hlt">tropical</span> <span class="hlt">central</span>-eastern <span class="hlt">Pacific</span> all year round, it is demonstrated that all models having a time-dependent realistic concentration of greenhouse gases (GHG) display a warming trend in the equatorial <span class="hlt">Pacific</span> that amplifies as the lead-time increases. In addition, these models' behaviors are nearly independent of the starting month of the hindcasts although the growth rates of the trend vary with the lead month. This key characteristic of the forecasted SST trend in the equatorial <span class="hlt">Pacific</span> is also identified in the NCAR CCSM3 hindcasts that have the GHG concentration for a fixed year. This suggests that a global warming forcing may not play a significant role in generating the spurious warming trend of the coupled models' SST hindcasts in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. This model SST trend in the <span class="hlt">tropical</span> <span class="hlt">central</span>-eastern <span class="hlt">Pacific</span>, which is opposite to the observed one, causes a developing El Niño-like warming bias in the forecasted SST with its peak in boreal winter. Its implications for seasonal prediction are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15.4928B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15.4928B"><span><span class="hlt">Tropical</span> <span class="hlt">Pacific</span> sea surface salinity variability derived from SMOS data: Comparison with in-situ observations.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ballabrera, Joaquim; Hoareau, Nina; Umbert, Marta; Martínez, Justino; Turiel, Antonio</p> <p>2013-04-01</p> <p>Prediction of El Niño/Southern Oscillation (ENSO), and its relation with global climate anomalies, continues to be an important research effort in short-term climate forecasting. This task has become even more challenging as researchers are becoming more and more convinced that there is not a single archetypical El Niño (or La Niña) pattern, but several. During some events (called now Standard or East <span class="hlt">Pacific</span>), the largest temperature anomalies are located at the eastern part of the <span class="hlt">Pacific</span>. However, during some of the most recent events, the largest anomalies are restricted to the <span class="hlt">central</span> part of the <span class="hlt">Pacific</span> Ocean, and are now called <span class="hlt">Central</span> <span class="hlt">Pacific</span> or Modoki (a Japanese word for "almost") events. Although the role of salinity in operational ENSO forecasting was initially neglected (in contrast with temperature, sea level, or surface winds), recent studies have shown that salinity does play a role in the preconditioning of ENSO. Moreover, some researchers suggest that sea surface salinity might play a role (through the modulation of the western <span class="hlt">Pacific</span> barrier layer) to favor the Standard or the Modoki nature of each event. Sea Surface Salinity maps are being operationally generated from microwave (L-band, 1.4 Ghz) brightness temperature maps. The L-band frequency was chosen because is the optimal one for ocean salinity measurements. However, after three years of satellite data, it has been found that noise in brightness temperatures (due to natural and artificial sources) is larger than expected. Moreover, the retrieval of SSS information requires special care because of the low sensitivity of the brightness temperature to SSS: from 0.2-0.8 K per salinity unit. Despite of all these facts, current accuracy of SS maps ranges from 0.2-0.4, depending on the processing level and the region being considered. We present here our study about the salinity variability in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean from the 9-day, 0.25 bins salinity maps derived from the SMOS</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.A42E..01G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.A42E..01G"><span>Sustaining a Moored Ocean Observing System in the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span>: The Evolution of the TAO Array</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Grissom, K.; Kessler, W. S.; McArthur, S.</p> <p>2016-12-01</p> <p>The <span class="hlt">Tropical</span> Atmosphere Ocean (TAO) array has been a major observational component of El Niño Southern Oscillation (ENSO) research and operational climate forecasting since its conception in 1984. Developed by NOAA's <span class="hlt">Pacific</span> Marine Environmental Laboratory (PMEL) in response to the poorly-observed 1982-1983 El Niño, the moored buoy array was completed in 1994 and transitioned from PMEL to NOAA's National Data Buoy Center (NDBC) in 2005. During this transition, the TAO Refresh project was initiated to address equipment obsolescence and the need for more real-time data. Completed in 2011, the "TAO Refresh" array has new capabilities and added value. Then in 2012, federal resource shortfalls threatened the future sustainability of this array. The resulting limited maintenance caused a decline in real-time data, yet it also served as the impetus to focus international attention on the demands of sustaining an observing system capable of monitoring the <span class="hlt">tropical</span> ocean-atmosphere interaction. To continue collecting observations at historical levels, NOAA and partners needed an alternate strategy, and to this end conceived the international TPOS 2020 project, the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Observing System for 2020. At more than 30 years, the TAO array stands as one of the longest sustained in-situ ocean observing networks in the world and provides a rare long-term record of a dominant climate signal. Here we review the evolution of the TAO array, from its development at PMEL, to its transition and modernization at NDBC, and provide a preview of its future as a key element of the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Observing System.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001JGR...106..879A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001JGR...106..879A"><span>Remote forcing at the Last Glacial Maximum in the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Andreasen, Dyke H.; Ravelo, A. Christina; Broccoli, Anthony J.</p> <p>2001-01-01</p> <p>We present results of a Last Glacial Maximum (LGM) wind stress sensitivity experiment using a high-resolution ocean general circulation model of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean. LGM wind stress, used to drive the ocean model, was generated using an atmospheric general circulation model simulation forced by LGM boundary conditions as part of the Paleoclimate Modeling Intercomparison Project (PMIP) [Broccoli, 2000]. LGM wind stress anomalies were large in the western half of the basin, yet there was a significant hydrographic response in the eastern half. This ocean model experiment hind casts changes that are in close agreement with paleoceanographic data from the entire region, even without the explicit modeling of the air-sea interactions. Data and model both predict that the annual average thermocline tilt across the basin was enhanced. Data and model are consistent with a stronger equatorial undercurrent which shoaled to the west of where it does today, and stronger advection of water from the Peru Current into the east equatorial <span class="hlt">Pacific</span> and across the equator. Paleoproductivity and sea surface temperature (SST) data are interpreted in light of the modeling results, indicating that paleoproductivity changes were related to wind-forced dynamical changes resulting from LGM boundary conditions, while SST changes were related to independent, possibly radiative, forcing. Overall, our results imply that much of the dynamic response of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> during the LGM can be explained by wind field changes resulting from global LGM boundary conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRC..121.7326Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRC..121.7326Z"><span>A modulating effect of <span class="hlt">Tropical</span> Instability Wave (TIW)-induced surface wind feedback in a hybrid coupled model of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Rong-Hua</p> <p>2016-10-01</p> <p><span class="hlt">Tropical</span> Instability Waves (TIWs) and the El Niño-Southern Oscillation (ENSO) are two air-sea coupling phenomena that are prominent in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, occurring at vastly different space-time scales. It has been challenging to adequately represent both of these processes within a large-scale coupled climate model, which has led to a poor understanding of the interactions between TIW-induced feedback and ENSO. In this study, a novel modeling system was developed that allows representation of TIW-scale air-sea coupling and its interaction with ENSO. Satellite data were first used to derive an empirical model for TIW-induced sea surface wind stress perturbations (τTIW). The model was then embedded in a basin-wide hybrid-coupled model (HCM) of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. Because τTIW were internally determined from TIW-scale sea surface temperatures (SSTTIW) simulated in the ocean model, the wind-SST coupling at TIW scales was interactively represented within the large-scale coupled model. Because the τTIW-SSTTIW coupling part of the model can be turned on or off in the HCM simulations, the related TIW wind feedback effects can be isolated and examined in a straightforward way. Then, the TIW-scale wind feedback effects on the large-scale mean ocean state and interannual variability in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> were investigated based on this embedded system. The interactively represented TIW-scale wind forcing exerted an asymmetric influence on SSTs in the HCM, characterized by a mean-state cooling and by a positive feedback on interannual variability, acting to enhance ENSO amplitude. Roughly speaking, the feedback tends to increase interannual SST variability by approximately 9%. Additionally, there is a tendency for TIW wind to have an effect on the phase transition during ENSO evolution, with slightly shortened interannual oscillation periods. Additional sensitivity experiments were performed to elucidate the details of TIW wind effects on SST evolution during ENSO</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004cosp...35..706Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004cosp...35..706Z"><span>Role of sea surface wind stress forcing on transport between <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> and Indian Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhao, Q.</p> <p></p> <p>Using an Indian-<span class="hlt">Pacific</span> Ocean Circulation Model (IPOM) a simulation study on the Transports of between <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> and Indian Ocean such as Indonesian Through flow (ITF) has been done. IPOM covered the area 25°E-70°W, 35°S-60°N. There are 31 levels in the vertical with 22 levels upper 400m in it. The horizontal resolution is 1/3° lat x 1.5° lon between 10°S and 10°N. The coastline and ocean topography of IPOM is prepared from Scripps topography data on 1x1°grid. Forcing IPOM with monthly observational wind stress in 1990-1999 the interannual variation of sea temperature has been reproduced well, not only on El Nino in the <span class="hlt">Pacific</span> but also on Indian Ocean Dipole (IOD). Therefore, the oceanic circulations in the <span class="hlt">tropical</span> ocean are reasonable. The analyses of the oceanic circulations from the simulations suggest that the transport southward through Makassar Strait is the primary route of thermocline water masses from the North <span class="hlt">Pacific</span> to the Indonesian sea. The transport westward through Bali-Western Australian Transect (BWAT, at 117.5E) can be thought as the final output of ITF through the archipelago to Indian Ocean. The transport westward through BWAT is in 8-12S above 150m, its core centered near surface 10S, which looks like a jet. The westward velocity is more than 50 cm/s. The transport shows significant seasonal and interannual variations. The maximum is in Jul-Oct, minimum in Jan-Mar. These results are consistent with some observation basically. The correlation analyses indict that the variations of transport westward is related with the southeasterly anomaly in the east <span class="hlt">tropical</span> Indian ocean. The transport variation lags wind anomaly about 3 months. The correlation coefficient is more than 0.6. The transport is strong during IOD, for example in 1994 and 1997. The variations are also related with the northwesterly anomaly in the center equatorial <span class="hlt">Pacific</span> and the easterly in the eastern equatorial <span class="hlt">Pacific</span>. The transport is strong in most ENSO</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20170003686','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20170003686"><span>The 2015/16 El Niño Event in Context of the MERRA-2 Reanalysis: A Comparison of the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> with 1982/83 and 1997/98</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lim, Young-Kwon; Kovach, Robin M.; Pawson, Steven; Vernieres, Guillaume</p> <p>2017-01-01</p> <p>The 2015-2016 El Nino is analyzed using atmospheric/oceanic analysis produced using the Goddard Earth Observing System (GEOS) data assimilation systems. As well as describing the structure of the event, a theme of the work is to compare and contrast it with two other strong El Ninos, in 1982/1983 and 1997/1998. These three El Nino events are included in the Modern-Era Retrospective analysis for Research and Applications (MERRA) and in the more recent MERRA-2 reanalyses. MERRA-2 allows a comparison of fields derived from the underlying GEOS model, facilitating a more detailed comparison of physical forcing mechanisms in the El Nino events. Various atmospheric/oceanic structures indicate that the 2015/2016 El Nino maximized in the Nino3.4 region, with the large region of warming over most of the <span class="hlt">Pacific</span> and Indian Ocean. The eastern <span class="hlt">tropical</span> Indian Ocean, Maritime Continent, and western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> are found to be less dry in boreal winter, compared to the earlier two strong events. While the 2015/2016 El Nino had an earlier occurrence of the equatorial <span class="hlt">Pacific</span> warming and was the strongest event on record in the <span class="hlt">central</span> <span class="hlt">Pacific</span>, the 1997/1998 event exhibited a more rapid growth due to stronger westerly wind bursts and Madden-Julian Oscillation during spring, making it the strongest El Nino in the eastern <span class="hlt">Pacific</span>. Compared to 1982/1983 and 1997/1998, the 2015/2016 event has a shallower thermocline over the eastern <span class="hlt">Pacific</span> with a weaker zonal contrast of sub-surface water temperatures along the equatorial <span class="hlt">Pacific</span>. While the three major ENSO events have similarities, each are unique when looking at the atmosphere and ocean surface and sub-surface.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25104384','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25104384"><span>Oceanography. Centennial changes in North <span class="hlt">Pacific</span> anoxia linked to <span class="hlt">tropical</span> trade winds.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Deutsch, Curtis; Berelson, William; Thunell, Robert; Weber, Thomas; Tems, Caitlin; McManus, James; Crusius, John; Ito, Taka; Baumgartner, Timothy; Ferreira, Vicente; Mey, Jacob; van Geen, Alexander</p> <p>2014-08-08</p> <p>Climate warming is expected to reduce oxygen (O2) supply to the ocean and expand its oxygen minimum zones (OMZs). We reconstructed variations in the extent of North <span class="hlt">Pacific</span> anoxia since 1850 using a geochemical proxy for denitrification (δ(15)N) from multiple sediment cores. Increasing δ(15)N since ~1990 records an expansion of anoxia, consistent with observed O2 trends. However, this was preceded by a longer declining δ(15)N trend that implies that the anoxic zone was shrinking for most of the 20th century. Both periods can be explained by changes in winds over the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> that drive upwelling, biological productivity, and O2 demand within the OMZ. If equatorial <span class="hlt">Pacific</span> winds resume their predicted weakening trend, the ocean's largest anoxic zone will contract despite a global O2 decline. Copyright © 2014, American Association for the Advancement of Science.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/1344036-response-tropical-pacific-ocean-el-nino-versus-global-warming','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/1344036-response-tropical-pacific-ocean-el-nino-versus-global-warming"><span>Response of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean to El Niño versus global warming</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Liu, Fukai; Luo, Yiyong; Lu, Jian</p> <p></p> <p>Climate models project an El Niño-like SST response in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean to global warming (GW). By employing the Community Earth System Model (CESM) and applying an overriding technique to its ocean component, Parallel Ocean Program version 2 (POP2), this study investigates the similarity and difference of formation mechanism for the changes in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean under El Niño and GW. Results show that, despite sharing some similarities between the two scenarios, there are many significant distinctions between GW and El Niño: 1) the phase locking of the seasonal cycle reduction is more notable under GW compared withmore » El Niño, implying more extreme El Niño events in the future; 2) in contrast to the penetration of the equatorial subsurface temperature anomaly that appears to propagate in the form of an oceanic equatorial upwelling Kelvin wave during El Niño, the GW-induced subsurface temperature anomaly manifest in the form of off-equatorial upwelling Rossby waves; 3) while significant across-equator northward heat transport (NHT) is induced by the wind stress anomalies associated with El Niño, little NHT is found at the equator due to a symmetric change in the shallow meridional overturning circulation that appears to be weakened in both North and South <span class="hlt">Pacific</span> under GW; and 4) the maintaining mechanisms for the eastern equatorial <span class="hlt">Pacific</span> warming are also substantially different.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018GeoRL..45..354Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018GeoRL..45..354Z"><span>Dominant Role of Atlantic Multidecadal Oscillation in the Recent Decadal Changes in Western North <span class="hlt">Pacific</span> <span class="hlt">Tropical</span> Cyclone Activity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Wei; Vecchi, Gabriel A.; Murakami, Hiroyuki; Villarini, Gabriele; Delworth, Thomas L.; Yang, Xiaosong; Jia, Liwei</p> <p>2018-01-01</p> <p>Over the 1997-2014 period, the mean frequency of western North <span class="hlt">Pacific</span> (WNP) <span class="hlt">tropical</span> cyclones (TCs) was markedly lower ( 18%) than the period 1980-1996. Here we show that these changes were driven by an intensification of the vertical wind shear in the southeastern/eastern WNP tied to the changes in the Walker circulation, which arose primarily in response to the enhanced sea surface temperature (SST) warming in the North Atlantic, while the SST anomalies associated with the negative phase of the <span class="hlt">Pacific</span> Decadal Oscillation in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> and the anthropogenic forcing play only secondary roles. These results are based on observations and experiments using the Geophysical Fluid Dynamics Laboratory Forecast-oriented Low-ocean Resolution Coupled Climate Model coupled climate model. The present study suggests a crucial role of the North Atlantic SST in causing decadal changes to WNP TC frequency.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70159431','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70159431"><span>Holocene variability in the intensity of wind-gap upwelling in the <span class="hlt">tropical</span> eastern <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Toth, Lauren T.; Aronson, Richard B.; Cheng, Hai; Edwards, R. Lawrence</p> <p>2015-01-01</p> <p>Wind-driven upwelling in <span class="hlt">Pacific</span> Panamá is a significant source of oceanographic variability in the <span class="hlt">tropical</span> eastern <span class="hlt">Pacific</span>. This upwelling system provides a critical teleconnection between the Atlantic and <span class="hlt">tropical</span> <span class="hlt">Pacific</span> that may impact climate variability on a global scale. Despite its importance to oceanographic circulation, ecology, and climate, little is known about the long-term stability of the Panamanian upwelling system or its interaction with climatic forcing on millennial time scales. Using a combination of radiocarbon and U-series dating of fossil corals collected in cores from five sites across <span class="hlt">Pacific</span> Panamá, we reconstructed the local radiocarbon reservoir correction, ΔR, from ~6750 cal B.P. to present. Because the ΔR of shallow-water environments is elevated by upwelling, our data set represents a millennial-scale record of spatial and temporal variability of the Panamanian upwelling system. The general oceanographic gradient from relatively strong upwelling in the Gulf of Panamá to weak-to-absent upwelling in the Gulf of Chiriquí was present throughout our record; however, the intensity of upwelling in the Gulf of Panamá varied significantly through time. Our reconstructions suggest that upwelling in the Gulf of Panamá is weak at present; however, the middle Holocene was characterized by periods of enhanced upwelling, with the most intense upwelling occurring just after of a regional shutdown in the development of reefs at ~4100 cal B.P. Comparisons with regional climate proxies suggest that, whereas the Intertropical Convergence Zone is the primary control on modern upwelling in <span class="hlt">Pacific</span> Panamá, the El Niño–Southern Oscillation drove the millennial-scale variability of upwelling during the Holocene.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhDT.......148S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhDT.......148S"><span>Transport and Thermohaline Structure in the Western <span class="hlt">Tropical</span> North <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schonau, Martha Coakley</p> <p></p> <p>Transport and thermohaline structure of water masses and their respective variability are observed and modeled in the western <span class="hlt">tropical</span> North <span class="hlt">Pacific</span> using autonomous underwater gliders, Argo climatology and a numerical ocean state estimate. The North Equatorial Current (NEC) advects subtropical and subpolar water masses into the region that are transported equatorward by the Mindanao Current (MC). Continuous glider observations of these two currents from June 2009 to December 2013 provide absolute geostrophic velocity, water mass structure, and transport. The observations are compared to Argo climatology (Roemmich and Gilson, 2009), wind and precipitation to assess forcing, and annual and interannual variability. Observations are assimilated into a regional ocean state estimate (1/6°) to examine regional transport variability and its relationship to the El Nino-Southern Oscillation phenomena (ENSO). The NEC, described in Chapter 1, is observed along 134.3°E, from 8.5°N to 16.5°N. NEC thermocline transport is relatively constant, with a variable subthermocline transport that is distinguished by countercurrents centered at 9.6°N and 13.1°N. Correlation between thermocline and subthermocline transport is strong. Isopycnals with subducted water masses, the North <span class="hlt">Pacific</span> <span class="hlt">Tropical</span> Water and North <span class="hlt">Pacific</span> Intermediate Water, have the greatest fine-scale thermohaline variance. The NEC advects water masses into the MC, described in Chapter 2, that flows equatorward along the coast of Mindanao. Gliders observed the MC at a mean latitude of 8.5°N. The Mindanao Undercurrent (MUC) persists in the subthermocline offshore of the MC, with a net poleward transport of intermediate water typical of South <span class="hlt">Pacific</span> origin. The variable subthermocline transport in the MC/MUC has an inverse linear relationship with the Nino 3.4 index and strongly impacts total transport variability. For each the MC and NEC, surface salinity and thermocline depth have a strong relationship with ENSO</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20010114458','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20010114458"><span>Whole Air Sampling During NASA's March-April 1999 <span class="hlt">Pacific</span> Exploratory Expedition (PEM-<span class="hlt">Tropics</span> B)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Blake, Donald R.</p> <p>2001-01-01</p> <p>University of California, Irvine (UCI) collected more than 4500 samples whole air samples collected over the remote <span class="hlt">Pacific</span> Ocean during NASA's Global Tropospheric Experiment (GTE) <span class="hlt">Pacific</span> Exploratory Mission-<span class="hlt">Tropics</span> B (PEM-<span class="hlt">Tropics</span> B) in March and early April 1999. Approximately 140 samples during a typical 8-hour DC-8 flight, and 120 canisters for each 8-hour flight aboard the P-3B. These samples were obtained roughly every 3-7 min during horizontal flight legs and 1-3 min during vertical legs. The filled canisters were analyzed in the laboratory at UCI within ten days of collection. The mixing ratios of 58 trace gases comprising hydrocarbons, halocarbons, alkyl nitrates and DMS were reported (and archived) for each sample. Two identical analytical systems sharing the same standards were operated simultaneously around the clock to improve canister turn-around time and to keep our measurement precision optimal. This report presents a summary of the results for sample collected.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.C21D1155C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.C21D1155C"><span>Role of the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> in recent Antarctic Sea-Ice Trends</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Codron, F.; Bardet, D.; Allouache, C.; Gastineau, G.; Friedman, A. R.; Douville, H.; Voldoire, A.</p> <p>2017-12-01</p> <p>The recent (up to 2016) trends in Antarctic sea-ice cover - a global increase masking a dipole between the Ross and Bellingshausen-Weddel seas - are still not well understood, and not reproduced by CMIP5 coupled climate models. We here explore the potential role of atmospheric circulation changes around the Amundsen Sea, themselves possibly forced by <span class="hlt">tropical</span> SSTs, an explanation that has been recently advanced. As a first check on this hypothesis, we compare the atmospheric circulation trends simulated by atmospheric GCMs coupled with an ocean or with imposed SSTs (AMIP experiment from CMIP5); the latter being in theory able to reproduce changes caused by natural SST variability. While coupled models simulate in aggregate trends that project on the SAM structure, strongest in summer, the AMIP simulations add in the winter season a pronounced Amundsen Sea Low signature (and a PNA signature in the northern hemisphere) both consistent with a Niña-like trend in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. We then use a specific coupled GCM setup, in which surface wind anomalies over the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> are strongly nudged towards the observed ones, including their interannual variability, but the model is free to evolve elsewhere. The two GCMs used then simulate a deepening trend in the Amundsen-Sea Low in winter, and are able to reproduce a dipole in sea-ice cover. Further analysis shows that the sea-ice dipole is partially forced by surface heat flux anomalies in early winter - the extent varying with the region and GCM used. The turbulent heat fluxes then act to damp the anomalies in late winter, which may however be maintained by ice-albedo feedbacks.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20010005258','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20010005258"><span>Compendium of NASA Data Base for the Global Tropospheric Experiment's <span class="hlt">Pacific</span> Exploratory Mission-<span class="hlt">Tropics</span> B (PEM-<span class="hlt">Tropics</span> B). Volume 1; DC-8</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Scott, A. Donald, Jr.; Kleb, Mary M.; Raper, James L.</p> <p>2000-01-01</p> <p>This report provides a compendium of NASA aircraft data that are available from NASA's Global Tropospheric Experiment's (GTE) <span class="hlt">Pacific</span> Exploratory Mission-<span class="hlt">Tropics</span> B (PEM-<span class="hlt">Tropics</span> B) conducted in March and April 1999. PEM-<span class="hlt">Tropics</span> B was conducted during the southern-<span class="hlt">tropical</span> wet season when the influence from biomass burning observed in PEM-<span class="hlt">Tropics</span> A was minimal. Major deployment sites were Hawaii, Kiritimati (Christmas Island), Tahiti, Fiji, and Easter Island. The broad goals of PEM-<span class="hlt">Tropics</span> B were to improved understanding of the oxidizing power of the atmosphere and the processes controlling sulfur aerosol formation and to establish baseline values for chemical species that are directly coupled to the oxidizing power and aerosol loading of the troposphere. The purpose of this document is to provide a representation of aircraft data that will be available in archived format via NASA Langley's Distributed Active Archive Center (DAAC) or are available through the GTE Project Office archive. The data format is not intended to support original research/analysis, but to assist the reader in identifying data that are of interest.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19990094165&hterms=clear+pool&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dclear%2Bpool','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19990094165&hterms=clear+pool&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dclear%2Bpool"><span><span class="hlt">Tropical</span> Intraseasonal Air-Sea Exchanges during the 1997 <span class="hlt">Pacific</span> Warming</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sui, C.-H.; Lau, K.-M.; Chou, S.-H.; Wang, Zihou</p> <p>1999-01-01</p> <p>The Madden Julian Oscillations (MJO) and associated westerly wind (WW) events account for much of the <span class="hlt">tropical</span> intraseasonal variability (TISV). The TISV has been suggested as an important stochastic forcing that may be one of the underlying causes for the observed irregularities of the El Nino-Southern Oscillation (ENSO). Recent observational studies and theories of interannual to interdecadal-scale variability suggest that ENSO may arise from different mechanisms depending on the basic states. The <span class="hlt">Pacific</span> warming event of 1997, being associated with a period of strong MJO and WW events, serves as a natural experiment for studying the possible role of TISV in triggering an ENSO event. We have performed a combined statistical and composite analysis of surface WW events based on the assimilated surface wind and sea level pressure for the period of 1980-1993, the SSM/I wind for the period of 1988-1997, and OLR. Results indicates that extratropical forcing contribute significantly to the evolution of MJO and establishment of WW events over the <span class="hlt">Pacific</span> warm pool. Following the major WW events, there appeared an eastward extension of equatorial warm SST anomalies from the western <span class="hlt">Pacific</span> warm pool. Such <span class="hlt">tropical</span>-extratropical interaction is particularly clear in the winter of 96-97 that leads to the recent warming event in 1997/98. From the above discussion, our current study on this subject is based on the hypothesis that 1) there is an enhanced air-sea interaction associated with TISV and the northerly surges from the extratropics in the initial phase of the 97/98 warming event, and 2) the relevant mechanisms are functions of the basic state of the coupled system (in terms of SST distribution and atmospheric mean circulation) that varies at the interannual and interdecadal time scale. We are analyzing the space-time structure of the northerly surges, their association with air-sea fluxes and upper ocean responses during the period of September 1996 to June 1997. The</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3971398','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3971398"><span>Indo-<span class="hlt">Pacific</span> Warm Pool Area Expansion, Modoki Activity, and <span class="hlt">Tropical</span> Cold-Point Tropopause Temperature Variations</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Xie, Fei; Li, Jianping; Tian, Wenshou; Li, Yanjie; Feng, Juan</p> <p>2014-01-01</p> <p>The <span class="hlt">tropical</span> cold-point tropopause temperature (CPTT), a potentially important indicator of global climate change, is of particular importance for understanding changes in stratospheric water vapor levels. Since the 1980s, the <span class="hlt">tropical</span> CPTT has shown not only interannual variations, but also a decreasing trend. However, the factors controlling the variations in the <span class="hlt">tropical</span> CPTT since the 1980s remain elusive. The present study reveals that the continuous expansion of the area of the Indo-<span class="hlt">Pacific</span> warm pool (IPWP) since the 1980s represents an increase in the total heat energy of the IPWP available to heat the tropospheric air, which is likely to expand as a result. This process lifts the <span class="hlt">tropical</span> cold-point tropopause height (CPTH) and leads to the observed long-term cooling trend of the <span class="hlt">tropical</span> CPTT. In addition, our analysis shows that Modoki activity is an important factor in modulating the interannual variations of the <span class="hlt">tropical</span> CPTT through significant effects on overshooting convection. PMID:24686481</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120010529','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120010529"><span>A Statistical Model of <span class="hlt">Tropical</span> Cyclone Tracks in the Western North <span class="hlt">Pacific</span> with ENSO-Dependent Cyclogenesis</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Yonekura, Emmi; Hall, Timothy M.</p> <p>2011-01-01</p> <p>A new statistical model for western North <span class="hlt">Pacific</span> Ocean <span class="hlt">tropical</span> cyclone genesis and tracks is developed and applied to estimate regionally resolved <span class="hlt">tropical</span> cyclone landfall rates along the coasts of the Asian mainland, Japan, and the Philippines. The model is constructed on International Best Track Archive for Climate Stewardship (IBTrACS) 1945-2007 historical data for the western North <span class="hlt">Pacific</span>. The model is evaluated in several ways, including comparing the stochastic spread in simulated landfall rates with historic landfall rates. Although certain biases have been detected, overall the model performs well on the diagnostic tests, for example, reproducing well the geographic distribution of landfall rates. Western North <span class="hlt">Pacific</span> cyclogenesis is influenced by El Nino-Southern Oscillation (ENSO). This dependence is incorporated in the model s genesis component to project the ENSO-genesis dependence onto landfall rates. There is a pronounced shift southeastward in cyclogenesis and a small but significant reduction in basinwide annual counts with increasing ENSO index value. On almost all regions of coast, landfall rates are significantly higher in a negative ENSO state (La Nina).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20000068999','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20000068999"><span>Biomass Burning Influences on the Composition of the Remote South <span class="hlt">Pacific</span> Troposphere: Analysis Based on Observations from PEM <span class="hlt">Tropics</span>-A</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Singh, H. B.; Viezee, W.; Chen, Y.; Bradshaw, J.; Sandholm, S.; Blake, D.; Blake, N.; Heikes, B.; Snow, J.; Talbot, R.; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20000068999'); toggleEditAbsImage('author_20000068999_show'); toggleEditAbsImage('author_20000068999_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20000068999_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20000068999_hide"></p> <p>1999-01-01</p> <p>Airborne, in-situ measurements from PEM-<span class="hlt">Tropics</span>-A (September/October 1996) are analyzed to show the presence of distinct pollution plumes in the middle-<span class="hlt">tropical</span> troposphere of the remote South <span class="hlt">Pacific</span> (10-30degS). These elevated plumes cause a relative maximum at about 5-7km attitude in the vertical distribution of primary and secondary species characteristic of fuel combustion and biomass burning (CO, C2H2, C2H6, CH3Cl, PAN, O3). Similar plumes were also observed at mid-latitudes in the middle troposphere during three flights east of New Zealand (40-45degS). In all, pollution plumes with CO larger than 100 ppb were observed 24 times on 7 separate flight days south of the equator. The observed plumes were generally embedded in very dry air. Ten-day back trajectory analysis supports the view that these originated from the biomass burning regions of South Africa (and South America) and were transported to the South <span class="hlt">Pacific</span> along long-distance subsiding trajectories. The chemical composition of the southern <span class="hlt">Pacific</span> troposphere analyzed from the PEM-<span class="hlt">Tropics</span>-A data is compared with data from the <span class="hlt">tropical</span> regions of the northern <span class="hlt">Pacific</span> (PEM-West-A) and southern Atlantic (TRACE-A) during the same Sept/Oct time period. Sizable perturbations in the abundance of ozone and its key precursors, resulting from the transport of pollution originating from biomass burning sources, are observed in much of the Southern Hemispheric troposphere.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_10 --> <div id="page_11" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="201"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ClDy...49.2291R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ClDy...49.2291R"><span>Predictability and prediction of persistent cool states of the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ramesh, Nandini; Cane, Mark A.; Seager, Richard; Lee, Dong Eun</p> <p>2017-10-01</p> <p>The <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Ocean displays persistently cool sea surface temperature (SST) anomalies that last several years to a decade, with either no El Niño events or a few weak El Niño events. These cause large-scale droughts in the extratropics, including major North American droughts such as the 1930s Dust Bowl, and also modulate the global mean surface temperature. Here we show that two models with different levels of complexity—the Zebiak-Cane intermediate model and the Geophysical Fluid Dynamics Laboratory Coupled Model version 2.1—are able to produce such periods in a realistic manner. We then test the predictability of these periods in the Zebiak-Cane model using an ensemble of experiments with perturbed initial states. Our results show that in most cases the cool mean state is predictable. We then apply this method to make retrospective forecasts of shifts in the decadal mean state and to forecast the mean state of the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Ocean for the upcoming decade. Our results suggest that the <span class="hlt">Pacific</span> will undergo a shift to a warmer mean state after the 2015-2016 El Niño. This could imply the cessation of the drier than normal conditions that have generally afflicted southwest North America since the 1997-1998 El Niño, as well as the twenty-first-century pause in global warming. Implications for our understanding of the origins of such persistent cool states and the possibility of improving predictions of large-scale droughts are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013CorRe..32...35B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013CorRe..32...35B"><span>Isolation of potential fungal pathogens in gorgonian corals at the <span class="hlt">Tropical</span> Eastern <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Barrero-Canosa, J.; Dueñas, L. F.; Sánchez, J. A.</p> <p>2013-03-01</p> <p>A major environmental problem in the ocean is the alarming increase in diseases affecting diverse marine organisms including corals. Environmental factors such as the rising seawater temperatures and terrestrial microbial input to the ocean have contributed to the increase in diseased organisms. We isolated and identified the fungal agents that may be leading to a disease in the <span class="hlt">Pacific</span> sea fan Pacifigorgia eximia (Gorgoniidae, Octocorallia) in the <span class="hlt">Tropical</span> Eastern <span class="hlt">Pacific</span>. We isolated thirteen fungal genera in healthy and diseased colonies including Aspergillus sydowii. Aspergillus has been previously identified as responsible for the mortality of gorgonian corals in the Caribbean. This disease was observed in the Eastern <span class="hlt">Pacific</span> affecting a completely different set of species nearly 30 years after the Caribbean outbreak, which concur with rising seawater temperatures and thermal anomalies that have been observed in the last 4 years.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMOS51A1975L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMOS51A1975L"><span><span class="hlt">Tropical</span> Atlantic Impacts on the Decadal Climate Variability of the <span class="hlt">Tropical</span> Ocean and Atmosphere.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, X.; Xie, S. P.; Gille, S. T.; Yoo, C.</p> <p>2015-12-01</p> <p>Previous studies revealed atmospheric bridges between the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, Atlantic, and Indian Ocean. In particular, several recent works indicate that the Atlantic sea surface temperature (SST) may contribute to the climate variability over the equatorial <span class="hlt">Pacific</span>. Inspired by these studies, our work aims at investigating the impact of the <span class="hlt">tropical</span> Atlantic on the entire <span class="hlt">tropical</span> climate system, and uncovering the physical dynamics under these <span class="hlt">tropical</span> teleconnections. We first performed a 'pacemaker' simulation by restoring the satellite era <span class="hlt">tropical</span> Atlantic SST changes in a fully coupled model - the CESM1. Results reveal that the Atlantic warming heats the Indo-Western <span class="hlt">Pacific</span> and cools the Eastern <span class="hlt">Pacific</span>, enhances the Walker circulation and drives the subsurface <span class="hlt">Pacific</span> to a La Niña mode, contributing to 60-70% of the above <span class="hlt">tropical</span> changes in the past 30 years. The same pan-<span class="hlt">tropical</span> teleconnections have been validated by the statistics of observations and 106 CMIP5 control simulations. We then used a hierarchy of atmospheric and oceanic models with different complexities, to single out the roles of atmospheric dynamics, atmosphere-ocean fluxes, and oceanic dynamics in these teleconnections. With these simulations we established a two-step mechanism as shown in the schematic figure: 1) Atlantic warming generates an atmospheric deep convection and induces easterly wind anomalies over the Indo-Western <span class="hlt">Pacific</span> in the form of Kelvin waves, and westerly wind anomalies over the eastern equatorial <span class="hlt">Pacific</span> as Rossby waves, in line with Gill's solution. This circulation changes warms the Indo-Western <span class="hlt">Pacific</span> and cools the Eastern <span class="hlt">Pacific</span> with the wind-evaporation-SST effect, forming a temperature gradient over the Indo-<span class="hlt">Pacific</span> basins. 2) The temperature gradient further generates a secondary atmospheric deep convection, which reinforces the easterly wind anomalies over the equatorial <span class="hlt">Pacific</span> and enhances the Walker circulation, triggering the <span class="hlt">Pacific</span> to a La Ni</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20060021457','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20060021457"><span><span class="hlt">Central</span> East <span class="hlt">Pacific</span> Flight Routing</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Grabbe, Shon; Sridhar, Banavar; Kopardekar, Parimal; Cheng, Nadia</p> <p>2006-01-01</p> <p>With the introduction of the Federal Aviation Administration s Advanced Technology and Oceanic Procedures system at the Oakland Oceanic Center, a level of automation now exists in the oceanic environment to potentially begin accommodating increased user preferred routing requests. This paper presents the results of an initial feasibility assessment which examines the potential benefits of transitioning from the fixed <span class="hlt">Central</span> East <span class="hlt">Pacific</span> routes to user preferred routes. As a surrogate for the actual user-provided routing requests, a minimum-travel-time, wind-optimal dynamic programming algorithm was developed and utilized in this paper. After first describing the characteristics (e.g., origin airport, destination airport, vertical distribution and temporal distribution) of the westbound flights utilizing the <span class="hlt">Central</span> East <span class="hlt">Pacific</span> routes on Dec. 14-16 and 19-20, the results of both a flight-plan-based simulation and a wind-optimal-based simulation are presented. Whereas the lateral and longitudinal distribution of the aircraft trajectories in these two simulations varied dramatically, the number of simulated first-loss-of-separation events remained relatively constant. One area of concern that was uncovered in this initial analysis was a potential workload issue associated with the redistribution of traffic in the oceanic sectors due to thc prevailing wind patterns.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015Geomo.246..220C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015Geomo.246..220C"><span>Main factors determining bioerosion patterns on rocky cliffs in a drowned valley estuary in the Colombian <span class="hlt">Pacific</span> (Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span>)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cobo-Viveros, Alba Marina; Cantera-Kintz, Jaime Ricardo</p> <p>2015-10-01</p> <p>Bioerosion is an important process that destroys coastal rocks in the <span class="hlt">tropics</span>. However, the rates at which this process occurs, the organisms involved, and the dynamics of rocky cliffs in <span class="hlt">tropical</span> latitudes have been less studied than in temperate and subtropical latitudes. To contribute to the knowledge of the bioerosion process in rocky cliffs on the <span class="hlt">Pacific</span> coast of Colombia (Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span>) we compared: 1) boring volume, 2) grain size distribution of the rocks, and 3) rock porosity, across three tidal zones of two cliffs with different wave exposure; these factors were related to the bioeroding community found. We observed that cliffs that were not exposed to wave action (IC, internal cliffs) exhibited high percentages of clays in their grain size composition, and a greater porosity (47.62%) and perforation (15.86%) than exposed cliffs (EC, external cliffs). However, IC also exhibited less diversity and abundance of bioeroding species (22 species and 314 individuals, respectively) compared to the values found in EC (41.11%, 14.34%, 32 and 491, respectively). The most abundant bioeroders were Petrolisthes zacae in IC and Pachygrapsus transversus in EC. Our findings show that the tidal zone is the common factor controlling bioerosion on both cliffs; in addition to the abundance of bioeroders on IC and the number of bioeroding species on EC. The integration of geology, sedimentology, and biology allows us to obtain a more comprehensive view of the patterns and trends in the process of bioerosion.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000EOSTr..81...13D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000EOSTr..81...13D"><span>Satellite captures trichodesmium blooms in the southwestern <span class="hlt">tropical</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dupouy, Cécile; Neveux, Jacques; Subramaniam, Ajit; Mulholland, Margaret R.; Montoya, Joseph P.; Campbell, Lisa; Carpenter, Edward J.; Capone, Douglas G.</p> <p></p> <p>Obtaining a true estimate of nitrogen fixation by cyanobacteria in the oceans, mainly Trichodesmium, is an important step toward understanding the entire nitrogen cycle in the <span class="hlt">tropical</span> ocean. This strictly anaerobic process, which has a high Fe requirement, could regulate atmospheric CO2 over geological time. For example, during interglacial periods, N2 fixation would be too low (low Fe) to balance denitrification and the ocean would lose its fixed nitrogen [Falkowski, 1997]. Has the level of marine nitrogen fixation been underestimated until now? High N2 fixation rates measured on Trichodesmium spp. communities have led to an upward revision of this marine flux [Capone et al, 1997]. Recent modeling studies and observations predict that N2 fixation could regulate the long-term N:P equilibrium in the oceans and balance denitrification [Tyrell, 1999; J L. Sarmiento and N. Gruber, manuscript in preparation, 1999].The major nitrogen fixer, Trichodesmium spp., which are filamentous, nonheterocystous N2-fixing cyanobacteria, has a nearly ubiquitous distribution in the euphotic zone of <span class="hlt">tropical</span> and subtropical seas and could play a major role in bringing new N to these oligotrophic systems. Satellite images from Sea-viewing Wide Field-of-view Sensor (SeaWiFs), the recently launched ocean color sensor, and data from a recent cruise, provide further evidence of the importance of Trichodesmium in the southwestern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ClDy..tmp...75Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ClDy..tmp...75Z"><span>On the relationship between ENSO and <span class="hlt">tropical</span> cyclones in the western North <span class="hlt">Pacific</span> during the boreal summer</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhao, Haikun; Wang, Chunzai</p> <p>2018-02-01</p> <p>The present paper uses the satellite era data from 1979 to 2015 to examine the relationship between El Niño-Southern Oscillation (ENSO) and <span class="hlt">tropical</span> cyclones (TCs) in the western North <span class="hlt">Pacific</span> (WNP) during the boreal summer from June to August. It is found that WNP TC variability is characterized by two major feature changes: (1) a significant reduction of the TC number since 1998 and (2) a stronger interannual relationship between ENSO and TCs since 1998. Results suggested that such changes are largely due to the synergy effects of a shifting ENSO and the <span class="hlt">Pacific</span> climate regime shift. Since 1998 with a cool <span class="hlt">Pacific</span> decadal oscillation phase switching from a warm phase, more La Niña and <span class="hlt">central</span> <span class="hlt">Pacific</span> (CP) El Niño events occur. The decreased low-level relative vorticity and increased vertical wind shear during 1998-2015 compared to 1979-1997 are responsible for the TC reduction. The stronger interannual relationship between ENSO and TCs since 1998 is closely associated the change of CP sea surface temperature. It enhances the associations of environmental factors including vertical wind shear and mid-level relative humidity with TCs and thus increases the interannual relationship between ENSO and TCs. These two feature changes also manifest in the mean TC genesis location, with a northwestward shift of the TC genesis location during 1998-2015 and an increased relation to El Niño Modoki index since 1998. This study has an important implication for TC outlooks in the WNP based on climate predictions and projections.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16943835','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16943835"><span>Controls on <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean productivity revealed through nutrient stress diagnostics.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Behrenfeld, Michael J; Worthington, Kirby; Sherrell, Robert M; Chavez, Francisco P; Strutton, Peter; McPhaden, Michael; Shea, Donald M</p> <p>2006-08-31</p> <p>In situ enrichment experiments have shown that the growth of bloom-forming diatoms in the major high-nitrate low-chlorophyll (HNLC) regions of the world's oceans is limited by the availability of iron. Yet even the largest of these manipulative experiments represents only a small fraction of an ocean basin, and the responses observed are strongly influenced by the proliferation of rare species rather than the growth of naturally dominant populations. Here we link unique fluorescence attributes of phytoplankton to specific physiological responses to nutrient stress, and use these relationships to evaluate the factors that constrain phytoplankton growth in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean on an unprecedented spatial scale. On the basis of fluorescence measurements taken over 12 years, we delineate three major ecophysiological regimes in this region. We find that iron has a key function in regulating phytoplankton growth in both HNLC and oligotrophic waters near the Equator and further south, whereas nitrogen and zooplankton grazing are the primary factors that regulate biomass production in the north. Application of our findings to the interpretation of satellite chlorophyll fields shows that productivity in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> basin may be 1.2-2.5 Pg C yr(-1) lower than previous estimates have suggested, a difference that is comparable to the global change in ocean production that accompanied the largest El Niño to La Niña transition on record.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://images.nasa.gov/#/details-GSFC_20171208_Archive_e001462.html','SCIGOVIMAGE-NASA'); return false;" href="https://images.nasa.gov/#/details-GSFC_20171208_Archive_e001462.html"><span><span class="hlt">Tropical</span> Storm Yagi in the North <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="https://images.nasa.gov/">NASA Image and Video Library</a></p> <p></p> <p>2017-12-08</p> <p>In early June, <span class="hlt">Tropical</span> storm Yagi developed from <span class="hlt">Tropical</span> Depression 03W in the Western North <span class="hlt">Pacific</span> Ocean. The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Terra satellite captured this true-color image on June 10 at 1:55 UTC (9:55 P.M.) as the storm was spinning near 25.0 north and 135.2 east, or about 396 miles (637 km) west of Iwo Jima, Japan. At that time, the storm had maximum sustained winds 51.7 mph (83.3 km/h). The image shows a tightly-wrapped circulation, a clouded eye and storm bands reached furthest out in the northeast quadrant. The <span class="hlt">tropical</span> depression first formed on June 6 east of the Philippines, and intensified on the weekend of June 8-9, when it was given the name of Yagi. Also known as Dante, the storm reached the maximum wind speeds on June 10 and 11, after which it began to weaken as it moved into cooler waters. On June 14, Yagi’s remnants passed about 200 miles south of Tokyo, and brought soaking rains to the coastline of Japan’s Honshu Island. Credit: NASA/GSFC/Jeff Schmaltz/MODIS Land Rapid Response Team NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1815714W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1815714W"><span>The role of the <span class="hlt">tropical</span> West <span class="hlt">Pacific</span> in the extreme northern hemisphere winter of 2013/14</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Watson, Peter; Weisheimer, Antje; Knight, Jeff; Palmer, Tim</p> <p>2016-04-01</p> <p>In the 2013/14 winter, the eastern USA was exceptionally cold, the Bering Strait region was exceptionally warm, California was in the midst of drought and the UK suffered severe flooding. It has been suggested that elevated SSTs in the <span class="hlt">tropical</span> West <span class="hlt">Pacific</span> (TWPAC) were partly to blame due to their producing a Rossby wavetrain that propagated into the extratropics. We find that seasonal forecasts with the <span class="hlt">tropical</span> atmosphere relaxed towards a reanalysis give 2013/14 winter-mean anomalies with strong similarities to those observed in the Northern Hemisphere, indicating that low-latitude anomalies had a role in the development of the extremes. Relaxing just the TWPAC produces a strong wavetrain over the North <span class="hlt">Pacific</span> and North America in January, but not in the winter-mean. This suggests that anomalies in this region alone had a large influence, but cannot explain the extremes through the whole winter. We also examine the response to applying the observed TWPAC SST anomalies in two atmospheric general circulation models. We find that this does produce winter-mean anomalies in the North <span class="hlt">Pacific</span> and North America resembling those observed, but that the <span class="hlt">tropical</span> forcing of Rossby waves due to the applied SST anomalies appears stronger than that in reanalysis, except in January. Therefore both experiments indicate that the TWPAC influence was important, but the true strength of the TWPAC influence is uncertain. None of the experiments indicate a strong systematic impact of the TWPAC anomalies on Europe.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMPP52B..04C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMPP52B..04C"><span>Water isotope variability across single rainfall events in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cobb, K. M.; Moerman, J. W.; Ellis, S. A.; Bennett, L.; Bosma, C.; Hitt, N. T.</p> <p>2017-12-01</p> <p>Water isotopologues provide a powerful diagnostic tool for probing the dynamical processes involved in the initiation and evolution of <span class="hlt">tropical</span> convective events, yet water isotope observations rarely meet the temporal resolution required to resolve such processes. Here we present timeseries of rainfall oxygen and hydrogen isotopologues across over 30 individual convective events sampled at 1- to 5-minute intervals at both terrestrial (Gunung Mulu National Park, 4N, 115W) and maritime (Kiritimati Island, 2N, 157W) sites located in the equatorial <span class="hlt">Pacific</span>. The sites are the loci of significant paleoclimate research that employ water isotopologues to reconstruct a variety of climatic parameters of interest over the last century, in the case of coral d18O, to hundreds of thousands of years before present, in the case of stalagmite d18O. As such, there is significant scientific value in refining our understanding of water isotope controls at these particular sites. Our results illustrate large, short-term excursions in water isotope values that far exceed the signals recovered in daily timeseries of rainfall isotopologues from the sites, illustrating the fundamental contribution of mesoscale processes in driving rainfall isotope variability. That said, the cross-event profiles exhibit a broad range of trajectories, even for events collected at the same time of day on adjoining days. Profiles collected at different phases of the 2015-2017 strong El Nino-Southern Oscillation cycle also exhibit appreciable variability. We compare our observations to hypothetical profiles from a 1-dimensional model of each rainfall event, as well as to output from 4-dimensional isotope-equipped, ocean-atmosphere coupled models of rainfall isotope variability in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. We discuss the implications of our findings for the interpretation of water isotope-based reconstructions of hydroclimate in the <span class="hlt">tropics</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20010008242','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20010008242"><span>Compendium of NASA Data Base for the Global Tropospheric Experiment's <span class="hlt">Pacific</span> Exploratory Mission - <span class="hlt">Tropics</span> B (PEM-<span class="hlt">Tropics</span> B). Volume 2; P-3B</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Scott, A. Donald, Jr.; Kleb, Mary M.; Raper, James L.</p> <p>2000-01-01</p> <p>This report provides a compendium of NASA aircraft data that are available from NASA's Global Tropospheric Experiment's (GTE) <span class="hlt">Pacific</span> Exploratory Mission-<span class="hlt">Tropics</span> B (PEM-<span class="hlt">Tropics</span> B) conducted in March and April 1999. PEM-<span class="hlt">Tropics</span> B was conducted during the southern-<span class="hlt">tropical</span> wet season when the influence from biomass burning observed in PEM-<span class="hlt">Tropics</span> A was minimal. Major deployment sites were Hawaii, Kiritimati (Christmas Island), Tahiti, Fiji, and Easter Island. The broad goals of PEM-<span class="hlt">Tropics</span> B were to improved understanding of the oxidizing power of the atmosphere and the processes controlling sulfur aerosol formation and to establish baseline values for chemical species that are directly coupled to the oxidizing power and aerosol loading of the troposphere. The purpose of this document is to provide a representation of aircraft data that will be available in archived format via NASA Langley's Distributed Active Archive Center (DAAC) or are available through the GTE Project Office archive. The data format is not intended to support original research/analysis, but to assist the reader in identifying data that are of interest.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19940038878&hterms=clear+pool&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dclear%2Bpool','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19940038878&hterms=clear+pool&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dclear%2Bpool"><span>Relationship between clouds and sea surface temperatures in the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Arking, Albert; Ziskin, Daniel</p> <p>1994-01-01</p> <p>Analysis of four years of earth radiation budget, cloud, and sea surface temperature data confirms that cloud parameters change dramatically when and where sea surface temperatures increase above approximately 300K. These results are based upon monthly mean values within 2.5 deg x 2.5 deg grid points over the 'warm pool' region of the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. The question of whether sea surface temperatures are influenced, in turn, by the radiative effects of these clouds (Ramanathan and Collins) is less clear. Such a feedback, if it exists, is weak. The reason why clouds might have so little influence, despite large changes in their longwave and shortwave radiative effects, might be that the sea surface responds to both the longwave heating and the shortwave cooling effects of clouds, and the two effects nearly cancel. There are strong correlations between the rate of change of sea surface temperature and any of the radiation budget parameters that are highly correlated with the incident solar flux-implying that season and latitude are the critical factors determining sea surface temperatures. With the seasonal or both seasonal and latitudinal variations removed, the rate of change of sea surface temperature shows no correlation with cloud-related parameters in the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.A33K3348L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.A33K3348L"><span>Interactions between <span class="hlt">tropical</span> cyclones and mid-latitude systems in the Northeastern <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lugo, A.; Abarca, S. F.; Raga, G. B.; Vargas, D. C.</p> <p>2014-12-01</p> <p>Major challenges in <span class="hlt">tropical</span> meteorology include the short-term forecast of <span class="hlt">tropical</span> cyclone (TC) intensity, which is defined as the maximum tangential wind. Several efforts have been made in order to reach this goal over the last decade: Among these efforts, the study of lightning in the TC inner core (the region inside a disc of 100 km radius from the center) as a proxy to deep convection, has the potential to be used as a predictor to forecast intensity (DeMaria et al, 2012, Mon. Wea. Rev., 140, 1828-1842).While most studies focus their objectives in studying the lightning flash density in the inner core, we study the probability of flash occurrence for intensifying and weakening cyclones. We have analyzed the trajectories of the observed 62 <span class="hlt">tropical</span> cyclones that developed in the basin from 2006 to 2009, and classified them into separate clusters according to their trajectories. These clusters can broadly be described as having trajectories mostly oriented: East-West, towards the <span class="hlt">central</span> <span class="hlt">Pacific</span>, NW far from the Mexican coast, parallel to the Mexican coast and recurving towards the Mexican coast.We estimate that probability of inner core lightning occurrence increases as cyclones intensify but the probability rapidly decrease as the systems weaken. This is valid for cyclones in most of the clusters. However, the cyclones that exhibit trajectories that recurve towards the Mexican coast, do not present the same relationship between intensity and inner-core lightning probability, these cyclones show little or no decrease in the lightning occurrence probability as they weaken.We hypothesize that one of the reasons for this anomalous behavior is likely the fact that these cyclones interact with mid-latitude systems. Mid-latitude systems are important in determining the recurving trajectory but they may also influence the TC by advecting mid-level moisture towards the TC inner core. This additional supply of moisture as the system is approaching land may enhance deep</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018GeCoA.222..508B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018GeCoA.222..508B"><span>Sources and processes affecting the distribution of dissolved Nd isotopes and concentrations in the West <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Behrens, Melanie K.; Pahnke, Katharina; Schnetger, Bernhard; Brumsack, Hans-Jürgen</p> <p>2018-02-01</p> <p>In the Atlantic, where deep circulation is vigorous, the dissolved neodymium (Nd) isotopic composition (expressed as ɛNd) is largely controlled by water mass mixing. In contrast, the factors influencing the ɛNd distribution in the <span class="hlt">Pacific</span>, marked by sluggish circulation, is not clear yet. Indication for regional overprints in the <span class="hlt">Pacific</span> is given based on its bordering volcanic islands. Our study aims to clarify the impact and relative importance of different Nd sources (rivers, volcanic islands), vertical (bio)geochemical processes and lateral water mass transport in controlling dissolved ɛNd and Nd concentration ([Nd]) distributions in the West <span class="hlt">Pacific</span> between South Korea and Fiji. We find indication for unradiogenic continental input from South Korean and Chinese rivers to the East China Sea. In the <span class="hlt">tropical</span> West <span class="hlt">Pacific</span>, volcanic islands supply Nd to surface and subsurface waters and modify their ɛNd to radiogenic values of up to +0.7. These radiogenic signatures allow detailed tracing of currents flowing to the east and differentiation from westward currents with open ocean <span class="hlt">Pacific</span> ɛNd composition in the complex <span class="hlt">tropical</span> <span class="hlt">Pacific</span> zonal current system. Modified radiogenic ɛNd of West <span class="hlt">Pacific</span> intermediate to bottom waters upstream or within our section also indicates non-conservative behavior of ɛNd due to boundary exchange at volcanic island margins, submarine ridges, and with hydrothermal particles. Only subsurface to deep waters (3000 m) in the open Northwest <span class="hlt">Pacific</span> show conservative behavior of ɛNd. In contrast, we find a striking correlation of extremely low (down to 2.77 pmol/kg Nd) and laterally constant [Nd] with the high-salinity North and South <span class="hlt">Pacific</span> <span class="hlt">Tropical</span> Water, indicating lateral transport of preformed [Nd] from the North and South <span class="hlt">Pacific</span> subtropical gyres into the study area. This observation also explains the previously observed low subsurface [Nd] in the <span class="hlt">tropical</span> West <span class="hlt">Pacific</span>. Similarly, Western South <span class="hlt">Pacific</span> <span class="hlt">Central</span> Water, Antarctic</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.H51I1382J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.H51I1382J"><span>Role of Equatorial <span class="hlt">Pacific</span> SST Anomalies in Precipitation over Western Americas</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jong, B. T.; Ting, M.; Seager, R.; Henderson, N.; Lee, D.</p> <p>2017-12-01</p> <p>El Niño, as the prime source of seasonal to interannual climate predictability, could impose impacts on the Americas from <span class="hlt">tropical</span> to mid-latitude regions. The teleconnection patterns are sensitive to the longitudinal location of the maximum <span class="hlt">tropical</span> sea surface temperature anomalies (SSTA). Meanwhile, slight differences in the location and configuration of the anomalous atmospheric circulations could differentiate between a wet and dry season regionally. For example, the 2015/16 strong El Niño event did not bring excessive precipitation to California despite expectations based on observational and model-based analyses. Whether the westward shift in the <span class="hlt">tropical</span> SSTA pattern played a key role during this event is examined. We conduct two SSTA-forced experimental runs in three NCAR GCMs (CCM3, CAM4, and CAM5): one forced by the observed February-March-April 2016 SSTA and the other forced by the model-ensemble mean forecast FMA 2016 SSTA from the North America Multi-Model Ensemble. The observed SSTAs, compared to the forecast SSTAs, are colder in the <span class="hlt">central</span>-eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> and slightly warmer in the westernmost <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. In response, all three models have a weaker and westward shifted low-pressure anomaly over the North <span class="hlt">Pacific</span> and west coast of North America when the observed SSTA is prescribed. As the result, northern California is either about the same or drier in the observed SSTA runs than in the forecast SSTA runs. However, the precipitation over southern California responds differently across models. One of the possible explanations is that in CCM3 the teleconnections respond mainly to the SSTA differences in the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span>; while in CAM4 and CAM5, the teleconnections are also sensitive to the small SSTA differences in the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. The results suggest that the <span class="hlt">tropical</span> SSTA differences matter for atmospheric circulations and precipitation over western Americas even though models disagree on the details of the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.A13E0324M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.A13E0324M"><span>Interannual variability of the frequency and intensity of <span class="hlt">tropical</span> cyclones striking the California coast</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mendez, F. J.; Rueda, A.; Barnard, P.; Mori, N.; Nakajo, S.; Albuquerque, J.</p> <p>2016-12-01</p> <p>Hurricanes hitting California have a very low ocurrence probability due to typically cool ocean temperature and westward tracks. However, damages associated to these improbable events would be dramatic in Southern California and understanding the oceanographic and atmospheric drivers is of paramount importance for coastal risk management for present and future climates. A statistical analysis of the historical events is very difficult due to the limited resolution of atmospheric and oceanographic forcing data available. In this work, we propose a combination of: (a) climate-based statistical downscaling methods (Espejo et al, 2015); and (b) a synthetic stochastic <span class="hlt">tropical</span> cyclone (TC) model (Nakajo et al, 2014). To build the statistical downscaling model, Y=f(X), we apply a combination of principal component analysis and the k-means classification algorithm to find representative patterns from large-scale may-to-november averaged monthly anomalies of SST and thermocline depth fields in <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> (predictor X) and the associated historical <span class="hlt">tropical</span> cyclones in Eastern North <span class="hlt">Pacific</span> basin (predictand Y). As data for the historical occurrence and paths of <span class="hlt">tropical</span> cyclones are scarce, we apply a stochastic TC model which is based on a Monte Carlo simulation of the joint distribution of track, minimum sea level pressure and translation speed of the historical events in the Eastern <span class="hlt">Central</span> <span class="hlt">Pacific</span> Ocean. Results will show the ability of the approach to explain the interannual variability of the frequency and intensity of TCs in Southern California, which is clearly related to post El Niño Eastern <span class="hlt">Pacific</span> and El Niño <span class="hlt">Central</span> <span class="hlt">Pacific</span>. References Espejo, A., Méndez, F.J., Diez, J., Medina, R., Al-Yahyai, S. (2015) Seasonal probabilistic forecasting of <span class="hlt">tropical</span> cyclone activity in the North Indian Ocean, Journal of Flood Risk Management, DOI: 10.1111/jfr3.12197 Nakajo, S., N. Mori, T. Yasuda, and H. Mase (2014) Global Stochastic <span class="hlt">Tropical</span> Cyclone Model Based on</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5459944','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5459944"><span>Recent enhancement of <span class="hlt">central</span> <span class="hlt">Pacific</span> El Niño variability relative to last eight centuries</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Liu, Yu; Cobb, Kim M.; Song, Huiming; Li, Qiang; Li, Ching-Yao; Nakatsuka, Takeshi; An, Zhisheng; Zhou, Weijian; Cai, Qiufang; Li, Jinbao; Leavitt, Steven W.; Sun, Changfeng; Mei, Ruochen; Shen, Chuan-Chou; Chan, Ming-Hsun; Sun, Junyan; Yan, Libin; Lei, Ying; Ma, Yongyong; Li, Xuxiang; Chen, Deliang; Linderholm, Hans W.</p> <p>2017-01-01</p> <p>The far-reaching impacts of <span class="hlt">central</span> <span class="hlt">Pacific</span> El Niño events on global climate differ appreciably from those associated with eastern <span class="hlt">Pacific</span> El Niño events. <span class="hlt">Central</span> <span class="hlt">Pacific</span> El Niño events may become more frequent in coming decades as atmospheric greenhouse gas concentrations rise, but the instrumental record of <span class="hlt">central</span> <span class="hlt">Pacific</span> sea-surface temperatures is too short to detect potential trends. Here we present an annually resolved reconstruction of NIÑO4 sea-surface temperature, located in the <span class="hlt">central</span> equatorial <span class="hlt">Pacific</span>, based on oxygen isotopic time series from Taiwan tree cellulose that span from 1190 AD to 2007 AD. Our reconstruction indicates that relatively warm Niño4 sea-surface temperature values over the late twentieth century are accompanied by higher levels of interannual variability than observed in other intervals of the 818-year-long reconstruction. Our results imply that anthropogenic greenhouse forcing may be driving an increase in <span class="hlt">central</span> <span class="hlt">Pacific</span> El Niño-Southern Oscillation variability and/or its hydrological impacts, consistent with recent modelling studies. PMID:28555638</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ClDy..tmp..920L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ClDy..tmp..920L"><span>Impact of chlorophyll bias on the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> mean climate in an earth system model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lim, Hyung-Gyu; Park, Jong-Yeon; Kug, Jong-Seong</p> <p>2017-12-01</p> <p>Climate modeling groups nowadays develop earth system models (ESMs) by incorporating biogeochemical processes in their climate models. The ESMs, however, often show substantial bias in simulated marine biogeochemistry which can potentially introduce an undesirable bias in physical ocean fields through biogeophysical interactions. This study examines how and how much the chlorophyll bias in a state-of-the-art ESM affects the mean and seasonal cycle of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> sea-surface temperature (SST). The ESM used in the present study shows a sizeable positive bias in the simulated <span class="hlt">tropical</span> chlorophyll. We found that the correction of the chlorophyll bias can reduce the ESM's intrinsic cold SST mean bias in the equatorial <span class="hlt">Pacific</span>. The biologically-induced cold SST bias is strongly affected by seasonally-dependent air-sea coupling strength. In addition, the correction of chlorophyll bias can improve the annual cycle of SST by up to 25%. This result suggests a possible modeling approach in understanding the two-way interactions between physical and chlorophyll biases by biogeophysical effects.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUOSOD12A..01H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUOSOD12A..01H"><span>Towards a <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Observing System for 2020 and Beyond.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hill, K. L.; Kessler, W. S.; Smith, N.</p> <p>2016-02-01</p> <p>The international TPOS 2020 Project arose out of a review workshop in January 2014, following challenges sustaining TAO-TRITON array in 2012, with the aim of rethinking the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> arrays in light of new scientific understanding and new ocean technology since its original design in the 1980s-90s. Observing and understanding ENSO remains a fundamental motivation, extending to biogeochemical phenomena, to processes on smaller scales that rectify into the low frequency, and, to the interaction of the coupled boundary layers of the upper ocean and lower atmosphere. Our primary customers remain the operational prediction centers and we will design an array to support research into physical processes, especially those not well represented in current-generation models. Current-generation forecast systems (data assimilation and the model physics) do not make effective-enough use of observations, thus the modeling centers are well-represented in the TPOS 2020 structure and our sampling is targeted to where the forecasts systems need guidance for improvement While we advocate evolution of the present arrays, the long climate records built up at mooring sites, repeated ship surveys, and island stations are fundamental to detecting and diagnosing both natural climate variability and detecting climate change signatures. Task teams have been established in specific topic areas. These will report in mid-2016, when a plan for the revised arrays will be presented to the agencies and governments, for completion of the evolution by 2020.This presentation will discuss the motivation, guiding principles, and potential changes of direction for the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> observing system.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_11 --> <div id="page_12" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="221"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1994ClDy....9..303T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1994ClDy....9..303T"><span>Decadal atmosphere-ocean variations in the <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Trenberth, Kevin E.; Hurrell, James W.</p> <p>1994-03-01</p> <p>Considerable evidence has emerged of a substantial decade-long change in the north <span class="hlt">Pacific</span> atmosphere and ocean lasting from about 1976 to 1988. Observed significant changes in the atmospheric circulation throughout the troposphere revealed a deeper and eastward shifted Aleutian low pressure system in the winter half year which advected warmer and moister air along the west coast of North America and into Alaska and colder air over the north <span class="hlt">Pacific</span>. Consequently, there were increases in temperatures and sea surface temperatures (SSTs) along the west coast of North America and Alaska but decreases in SSTs over the <span class="hlt">central</span> north <span class="hlt">Pacific</span>, as well as changes in coastal rainfall and streamflow, and decreases in sea ice in the Bering Sea. Associated changes occurred in the surface wind stress, and, by inference, in the Sverdrup transport in the north <span class="hlt">Pacific</span> Ocean. Changes in the monthly mean flow were accompanied by a southward shift in the storm tracks and associated synoptic eddy activity and in the surface ocean sensible and latent heat fluxes. In addition to the changes in the physical environment, the deeper Aleutian low increased the nutrient supply as seen through increases in total chlorophyll in the water column, phytoplankton and zooplankton. These changes, along with the altered ocean currents and temperatures, changed the migration patterns and increased the stock of many fish species. A north <span class="hlt">Pacific</span> (NP) index is defined to measure the decadal variations, and the temporal variability of the index is explored on daily, annual, interannual and decadal time scales. The dominant atmosphere-ocean relation in the north <span class="hlt">Pacific</span> is one where atmospheric changes lead SSTs by one to two months. However, strong ties are revealed with events in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, with changes in <span class="hlt">tropical</span> <span class="hlt">Pacific</span> SSTs leading SSTs in the north <span class="hlt">Pacific</span> by three months. Changes in the storm tracks in the north <span class="hlt">Pacific</span> help to reinforce and maintain the anomalous circulation in the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMGC21G..01T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMGC21G..01T"><span>Climatic Teleconnections Recorded By <span class="hlt">Tropical</span> Mountain Glaciers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Thompson, L. G.; Permana, D.; Mosley-Thompson, E.; Davis, M. E.</p> <p>2014-12-01</p> <p>Information from ice cores from the world's highest mountains in the <span class="hlt">Tropics</span> demonstrates both local climate variability and a high degree of teleconnectivity across the <span class="hlt">Pacific</span> basin. Here we examine recently recovered ice core records from glaciers near Puncak Jaya in Papua, Indonesia, which lie on the highest peak between the Himalayas and the South American Andes. These glaciers are located on the western side of the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> warm pool, which is the "center of action" for interannual climate variability dominated by El Niño-Southern Oscillation (ENSO). ENSO either directly or indirectly affects most regions of Earth and their populations. In 2010, two ice cores measuring 32.13 m and 31.25 m were recovered to bedrock from the East Northwall Firn ice field. Both have been analyzed in high resolution (~3 cm sample length, 1156 and 1606 samples, respectively) for stable isotopes, dust, major ions and tritium concentrations. To better understand the controls on the oxygen isotopic (δ18 O) signal for this region, daily rainfall samples were collected between January 2013 and February 2014 at five weather stations over a distance of ~90 km ranging from 9 meters above sea level (masl) on the southern coast up to 3945 masl. The calculated isotopic lapse rate for this region is 0.24 ‰/100m. Papua, Indonesian ice core records are compared to ice core records from Dasuopu Glacier in the <span class="hlt">central</span> Himalayas and from Quelccaya, Huascarán, Hualcán and Coropuna ice fields in the <span class="hlt">tropical</span> Andes of Peru on the eastern side of the <span class="hlt">Pacific</span> Ocean. The composite of the annual isotopic time series from these cores is significantly (R2 =0.53) related to <span class="hlt">tropical</span> <span class="hlt">Pacific</span> sea surface temperatures (SSTs), reflecting the strong linkage between <span class="hlt">tropical</span> <span class="hlt">Pacific</span> SSTs associated with ENSO and tropospheric temperatures in the low latitudes. New data on the already well-documented concomitant loss of ice on Quelccaya, Kilimanjaro in eastern Africa and the ice fields near Puncak</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRC..122.9209G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRC..122.9209G"><span>Complementary Use of Glider Data, Altimetry, and Model for Exploring Mesoscale Eddies in the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Solomon Sea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gourdeau, L.; Verron, J.; Chaigneau, A.; Cravatte, S.; Kessler, W.</p> <p>2017-11-01</p> <p>Mesoscale activity is an important component of the Solomon Sea circulation that interacts with the energetic low-latitude western boundary currents of the South <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Ocean carrying waters of subtropical origin before joining the equatorial <span class="hlt">Pacific</span>. Mixing associated with mesoscale activity could explain water mass transformation observed in the Solomon Sea that likely impacts El Niño Southern Oscillation dynamics. This study makes synergetic use of glider data, altimetry, and high-resolution model for exploring mesoscale eddies, especially their vertical structures, and their role on the Solomon Sea circulation. The description of individual eddies observed by altimetry and gliders provides the first elements to characterize the 3-D structure of these <span class="hlt">tropical</span> eddies, and confirms the usefulness of the model to access a more universal view of such eddies. Mesoscale eddies appear to have a vertical extension limited to the Surface Waters (SW) and the Upper Thermocline Water (UTW), i.e., the first 140-150 m depth. Most of the eddies are nonlinear, meaning that eddies can trap and transport water properties. But they weakly interact with the deep New Guinea Coastal Undercurrent that is a key piece of the equatorial circulation. Anticyclonic eddies are particularly efficient to advect salty and warm SW coming from the intrusion of equatorial <span class="hlt">Pacific</span> waters at Solomon Strait, and to impact the characteristics of the New Guinea Coastal Current. Cyclonic eddies are particularly efficient to transport South <span class="hlt">Pacific</span> <span class="hlt">Tropical</span> Water (SPTW) anomalies from the North Vanuatu Jet and to erode by diapycnal mixing the high SPTW salinity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003JGRD..108.4212N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003JGRD..108.4212N"><span>Intensity of prehistoric <span class="hlt">tropical</span> cyclones</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nott, Jonathan F.</p> <p>2003-04-01</p> <p>Prediction of future <span class="hlt">tropical</span> cyclone climate scenarios requires identification of quasi-periodicities at a variety of temporal scales. Extension of records to identify trends at century and millennial scales is important, but to date the emerging field of paleotempestology has been hindered by the lack of a suitable methodology to discern the intensity of prehistoric storms. Here a technique to quantify the <span class="hlt">central</span> pressure of prehistoric <span class="hlt">tropical</span> cyclones is presented in detail and demonstrated for the <span class="hlt">tropical</span> southwest <span class="hlt">Pacific</span> region. The importance of extending records to century time scales is highlighted for northeast Australia, where a virtual absence of category 5 cyclones during the 20th century stands in contrast to an active period of severe cyclogenesis during the previous century. Several land crossing storms during the 19th century achieved <span class="hlt">central</span> pressures lower than that ever recorded historically and close to the theoretical thermodynamic limit of storms for the region. This technique can be applied to all <span class="hlt">tropical</span> and subtropical regions globally and will assist in obtaining more realistic predictions for future storm scenarios with implications for insurance premiums, urban and infrastructural design, and emergency planning.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.noaanews.noaa.gov/stories2013/20130521_hurricaneoutlook_centralpacific.html','SCIGOVWS'); return false;" href="http://www.noaanews.noaa.gov/stories2013/20130521_hurricaneoutlook_centralpacific.html"><span>NOAA expects below-normal <span class="hlt">Central</span> <span class="hlt">Pacific</span> hurricane season</span></a></p> <p><a target="_blank" href="http://www.science.gov/aboutsearch.html">Science.gov Websites</a></p> <p></p> <p></p> <p>Hurricane Preparedness Week <em>El</em> Niño/Southern Oscillation (ENSO) Diagnostic Discussion FEMA Media Contact based upon the continuation of neutral <em>El</em> Niño - Southern Oscillation conditions. The <span class="hlt">Central</span> <span class="hlt">Pacific</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20160011263&hterms=eastern+western&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Deastern%2Bwestern%26Nf%3DPublication-Date%257CBTWN%2B20070101%2B20180604','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20160011263&hterms=eastern+western&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Deastern%2Bwestern%26Nf%3DPublication-Date%257CBTWN%2B20070101%2B20180604"><span>Western <span class="hlt">Pacific</span> Hydroclimate Linked to Global Climate Variability Over the Past Two Millennia</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Griffiths, Michael L.; Kimbrough, Alena K.; Gagan, Michael K.; Drysdale, Russell N.; Cole, Julia E.; Johnson, Kathleen R.; Zhao, Jian-Xin; Cook, Benjamin I.; Hellstrom, John C.; Hantoro, Wahyoe S.</p> <p>2016-01-01</p> <p>Interdecadal modes of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> ocean-atmosphere circulation have a strong influence on global temperature, yet the extent to which these phenomena influence global climate on multicentury timescales is still poorly known. Here we present a 2,000-year, multiproxy reconstruction of western <span class="hlt">Pacific</span> hydroclimate from two speleothem records for southeastern Indonesia. The composite record shows pronounced shifts in monsoon rainfall that are antiphased with precipitation records for East Asia and the <span class="hlt">central</span>-eastern equatorial <span class="hlt">Pacific</span>. These meridional and zonal patterns are best explained by a poleward expansion of the Australasian Intertropical Convergence Zone and weakening of the <span class="hlt">Pacific</span> Walker circulation (PWC) between B1000 and 1500 CE Conversely, an equatorward contraction of the Intertropical Convergence Zone and strengthened PWC occurred between B1500 and 1900 CE. Our findings, together with climate model simulations, highlight the likelihood that century-scale variations in <span class="hlt">tropical</span> <span class="hlt">Pacific</span> climate modes can significantly modulate radiatively forced shifts in global temperature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatCo...711719G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatCo...711719G"><span>Western <span class="hlt">Pacific</span> hydroclimate linked to global climate variability over the past two millennia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Griffiths, Michael L.; Kimbrough, Alena K.; Gagan, Michael K.; Drysdale, Russell N.; Cole, Julia E.; Johnson, Kathleen R.; Zhao, Jian-Xin; Cook, Benjamin I.; Hellstrom, John C.; Hantoro, Wahyoe S.</p> <p>2016-06-01</p> <p>Interdecadal modes of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> ocean-atmosphere circulation have a strong influence on global temperature, yet the extent to which these phenomena influence global climate on multicentury timescales is still poorly known. Here we present a 2,000-year, multiproxy reconstruction of western <span class="hlt">Pacific</span> hydroclimate from two speleothem records for southeastern Indonesia. The composite record shows pronounced shifts in monsoon rainfall that are antiphased with precipitation records for East Asia and the <span class="hlt">central</span>-eastern equatorial <span class="hlt">Pacific</span>. These meridional and zonal patterns are best explained by a poleward expansion of the Australasian Intertropical Convergence Zone and weakening of the <span class="hlt">Pacific</span> Walker circulation (PWC) between ~1000 and 1500 CE Conversely, an equatorward contraction of the Intertropical Convergence Zone and strengthened PWC occurred between ~1500 and 1900 CE. Our findings, together with climate model simulations, highlight the likelihood that century-scale variations in <span class="hlt">tropical</span> <span class="hlt">Pacific</span> climate modes can significantly modulate radiatively forced shifts in global temperature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.G24A..10Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.G24A..10Z"><span>Merging altimeter data with Argo profiles to improve observation of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> thermocline circulation and ENSO</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, D.; Lee, T.; Wang, F.; McPhaden, M. J.; Kessler, W. S.</p> <p>2016-12-01</p> <p>Meridional thermocline currents play an important role in the recharge and discharge of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> warm water during the development and transition of ENSO cycles. Previous analyses have shown large variations of the equatorward meridional thermocline convergence/divergence on ENSO and decadal time scales in the interior ocean. The total convergence/divergence is however unknown due to the lack of long term observation in the western boundary currents. Numerical modelling studies suggested a tendency of compensation between the interior and western boundary currents, but the exact compensation is model dependent. While Argo floats provide reasonable data coverage in the interior ocean, few floats are in the western boundary currents. Recent multi-mission satellite altimeter data and advanced processing techniques have resulted in higher resolution sea surface height anomaly (SSHA) products with better accuracy closer to the coasts. This study utilizes the statistical relationship between Argo dynamic height profiles and altimeter SSHA to calculate geostrophic thermocline currents in both the interior ocean and the western boundary of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. The derived thermocline currents in the western boundary are validated by a 3.5-year moored Acoustic Doppler Current Profiler (ADCP) measurement in the Mindanao Current and by a series of glider surveys (Davis et al. 2012) in the Solomon Sea. The meridional transport timeseries of the interior and western boundary currents in the thermocline show different lead-lag relationships to the Nino 3.4 index. Results will be discussed in the context of recent 2014-2015 El Nino development and the potential contribution to the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Observing System (TPOS).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JMetR..30..371Q','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JMetR..30..371Q"><span>TRMM-observed summer warm rain over the <span class="hlt">tropical</span> and subtropical <span class="hlt">Pacific</span> Ocean: Characteristics and regional differences</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Qin, Fang; Fu, Yunfei</p> <p>2016-06-01</p> <p>Based on the merged measurements from the TRMM Precipitation Radar and Visible and Infrared Scanner, refined characteristics (intensity, frequency, vertical structure, and diurnal variation) and regional differences of the warm rain over the <span class="hlt">tropical</span> and subtropical <span class="hlt">Pacific</span> Ocean (40ffiS-40ffiN, 120ffiE-70ffiW) in boreal summer are investigated for the period 1998-2012. The results reveal that three warm rain types (phased, pure, and mixed) exist over these regions. The phased warm rain, which occurs during the developing or declining stage of precipitation weather systems, is located over the <span class="hlt">central</span> to western Intertropical Convergence Zone, South <span class="hlt">Pacific</span> Convergence Zone, and Northwest <span class="hlt">Pacific</span>. Its occurrence frequency peaks at midnight and minimizes during daytime with a 5.5-km maximum echo top. The frequency of this warm rain type is about 2.2%, and it contributes to 40% of the regional total rainfall. The pure warm rain is characterized by typical stable precipitation with an echo top lower than 4 km, and mostly occurs in Southeast <span class="hlt">Pacific</span>. Although its frequency is less than 1.3%, this type of warm rain accounts for 95% of the regional total rainfall. Its occurrence peaks before dawn and it usually disappears in the afternoon. For the mixed warm rain, some may develop into deep convective precipitation, while most are similar to those of the pure type. The mixed warm rain is mainly located over the ocean east of Hawaii. Its frequency is 1.2%, but this type of warm rain could contribute to 80% of the regional total rainfall. The results also uncover that the mixed and pure types occur over the regions where SST ranges from 295 to 299 K, accompanied by relatively strong downdrafts at 500 hPa. Both the mixed and pure warm rains happen in a more unstable atmosphere, compared with the phased warm rain.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017GeoRL..44.8520N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017GeoRL..44.8520N"><span>Are we near the predictability limit of <span class="hlt">tropical</span> Indo-<span class="hlt">Pacific</span> sea surface temperatures?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Newman, Matthew; Sardeshmukh, Prashant D.</p> <p>2017-08-01</p> <p>The predictability of seasonal anomalies worldwide rests largely on the predictability of <span class="hlt">tropical</span> sea surface temperature (SST) anomalies. <span class="hlt">Tropical</span> forecast skill is also a key metric of climate models. We find, however, that despite extensive model development, the <span class="hlt">tropical</span> SST forecast skill of the operational North American Multi-Model Ensemble (NMME) of eight coupled atmosphere-ocean models remains close both regionally and temporally to that of a vastly simpler linear inverse model (LIM) derived from observed covariances of SST, sea surface height, and wind fields. The LIM clearly captures the essence of the predictable SST dynamics. The NMME and LIM skills also closely track and are only slightly lower than the potential skill estimated using the LIM's forecast signal-to-noise ratios. This suggests that the scope for further skill improvement is small in most regions, except in the western equatorial <span class="hlt">Pacific</span> where the NMME skill is currently much lower than the LIM skill.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA474394','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA474394"><span>Relationships Between Global Warming and <span class="hlt">Tropical</span> Cyclone Activity in the Western North <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2007-09-01</p> <p>In this work, we investigate the relationships between global warming and <span class="hlt">tropical</span> cyclone activity in the Western North <span class="hlt">Pacific</span> (WNP). Our...hypothesis is that global warming impacts on TC activity occur through changes in the large scale environmental factors (LSEFs) known to be important in...averages. Using a least squares fit, we identify global warming signals in both the SST and vertical wind shear data across the WNP. These signals vary</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4979033','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4979033"><span>Response of the <span class="hlt">Pacific</span> inter-<span class="hlt">tropical</span> convergence zone to global cooling and initiation of Antarctic glaciation across the Eocene Oligocene Transition</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Hyeong, Kiseong; Kuroda, Junichiro; Seo, Inah; Wilson, Paul A.</p> <p>2016-01-01</p> <p>Approximately 34 million years ago across the Eocene–Oligocene transition (EOT), Earth’s climate tipped from a largely unglaciated state into one that sustained large ice sheets on Antarctica. Antarctic glaciation is attributed to a threshold response to slow decline in atmospheric CO2 but our understanding of the feedback processes triggered and of climate change on the other contents is limited. Here we present new geochemical records of terrigenous dust accumulating on the sea floor across the EOT from a site in the <span class="hlt">central</span> equatorial <span class="hlt">Pacific</span>. We report a change in dust chemistry from an Asian affinity to a <span class="hlt">Central</span>-South American provenance that occurs geologically synchronously with the initiation of stepwise global cooling, glaciation of Antarctica and aridification on the northern continents. We infer that the inter-<span class="hlt">tropical</span> convergence zone of intense precipitation extended to our site during late Eocene, at least four degrees latitude further south than today, but that it migrated northwards in step with global cooling and initiation of Antarctic glaciation. Our findings point to an atmospheric teleconnection between extratropical cooling and rainfall climate in the <span class="hlt">tropics</span> and the mid-latitude belt of the westerlies operating across the most pivotal transition in climate state of the Cenozoic Era. PMID:27507793</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatSR...630647H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatSR...630647H"><span>Response of the <span class="hlt">Pacific</span> inter-<span class="hlt">tropical</span> convergence zone to global cooling and initiation of Antarctic glaciation across the Eocene Oligocene Transition</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hyeong, Kiseong; Kuroda, Junichiro; Seo, Inah; Wilson, Paul A.</p> <p>2016-08-01</p> <p>Approximately 34 million years ago across the Eocene-Oligocene transition (EOT), Earth’s climate tipped from a largely unglaciated state into one that sustained large ice sheets on Antarctica. Antarctic glaciation is attributed to a threshold response to slow decline in atmospheric CO2 but our understanding of the feedback processes triggered and of climate change on the other contents is limited. Here we present new geochemical records of terrigenous dust accumulating on the sea floor across the EOT from a site in the <span class="hlt">central</span> equatorial <span class="hlt">Pacific</span>. We report a change in dust chemistry from an Asian affinity to a <span class="hlt">Central</span>-South American provenance that occurs geologically synchronously with the initiation of stepwise global cooling, glaciation of Antarctica and aridification on the northern continents. We infer that the inter-<span class="hlt">tropical</span> convergence zone of intense precipitation extended to our site during late Eocene, at least four degrees latitude further south than today, but that it migrated northwards in step with global cooling and initiation of Antarctic glaciation. Our findings point to an atmospheric teleconnection between extratropical cooling and rainfall climate in the <span class="hlt">tropics</span> and the mid-latitude belt of the westerlies operating across the most pivotal transition in climate state of the Cenozoic Era.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.prh.noaa.gov/hnl/cphc','SCIGOVWS'); return false;" href="http://www.prh.noaa.gov/hnl/cphc"><span><span class="hlt">Central</span> <span class="hlt">Pacific</span> Hurricane Center - Honolulu, Hawai`i</span></a></p> <p><a target="_blank" href="http://www.science.gov/aboutsearch.html">Science.gov Websites</a></p> <p></p> <p></p> <p>Department of Commerce <span class="hlt">Central</span> <span class="hlt">Pacific</span> <em>Hurricane</em> Center National Oceanic and Atmospheric Administration Blank Tracking Maps â¾ Educational Resources Be Prepared! NWS <em>Hurricane</em> Prep Week Preparedness Weather <em>Hurricane</em> Season Outlook for 2018 2017-18 Hawaii Wet Season Summary and 2018 Dry Season Outlook USGS and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMPP11C1370H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMPP11C1370H"><span>Thermocline Temperature Variability Reveals Shifts in the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Mean State across Marine Isotope Stage 3</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hertzberg, J. E.; Schmidt, M. W.</p> <p>2014-12-01</p> <p>The eastern equatorial <span class="hlt">Pacific</span> (EEP) is one of the most dynamic oceanographic regions, making it a critical area for understanding past climate change. Despite this, there remains uncertainty on the climatic evolution of the EEP through the last glacial period. According to the ocean dynamical thermostat theory, warming (cooling) of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean may lead to a more La Niña (El Niño)-like mean state due to zonally asymmetric heating and subsequent easterly (westerly) wind anomalies at the equator (Clement and Cane, 1999). Attempts to understand these feedbacks on millennial timescales across Marine Isotope Stage 3 (MIS 3) have proven to be fruitful in the western equatorial <span class="hlt">Pacific</span> (WEP) (Stott et al., 2002), yet complimentary, high-resolution records from the EEP are lacking. To provide a more complete understanding of the feedback mechanisms of the dynamical thermostat across periods of abrupt climate change, we reconstruct thermocline temperature variability across MIS 3 from a sediment core located in the EEP, directly within the equatorial cold tongue upwelling region (core MV1014-02-17JC). Temperature anomalies in thermocline waters of the EEP are integrally linked to the ENSO system, with large positive and negative anomalies recorded during El Niño and La Niña events, respectively. Mg/Ca ratios in the thermocline-dwelling planktonic foraminifera Neogloboquadrina dutertrei were measured at 2 cm intervals, resulting in a temporal resolution of <200 years. Preliminary results across Interstadials 5-7 reveal warmer thermocline temperatures (an increase in Mg/Ca of .25 ± .02 mmol/mol) during periods of cooling following peak Interstadial warmth over Greenland, as seen from the NGRIP δ18O record. Thus, periods of cooling over Greenland appear to correspond to an El Niño-like mean state in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, in line with predictions of an ocean dynamical thermostat. Interestingly, Heinrich Event 3 corresponds to cooler thermocline</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMPP51A1057T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMPP51A1057T"><span>Asymmetric Signature of Glacial Antarctic Intermediate Water in the <span class="hlt">Central</span> South <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tapia, R.; Nuernberg, D.; Ho, S. L.; Lamy, F.; Ullermann, J.; Gersonde, R.; Tiedemann, R.</p> <p>2017-12-01</p> <p>Southern Ocean Intermediate Waters (SOIWs) play a key role in modulating the global climate on glacial-interglacial time scales as they connect the Southern Ocean and the <span class="hlt">tropics</span>. Despite their importance, the past evolution of the SOIWs in the <span class="hlt">central</span> South <span class="hlt">Pacific</span> is largely unknown due to a dearth of sedimentary archives. Here we compare Mg/Ca-temperature, stable carbon and oxygen isotope records from surface-dwelling (G. bulloides) and deep-dwelling (G. inflata) planktic foraminifera at site PS75/059-2 (54°12.9' S, 125°25.53' W; recovery 13.98 m; 3.613 m water depth), located north of the modern Subantarctic Front. Our study focuses on the temperature and salinity variability controlled by SOIWs, which were subducted at the Subantarctic Front during the Last Glacial Maximum (LGM; 29-17ka BP) and the Penultimate Glacial Maximum (PGM; 180-150ka BP). During both glacial periods conditions at the subsurface ocean were colder and fresher relative to the Holocene (<10ka) suggesting an enhanced presence of SOIWs. In spite of the comparable subsurface cooling during both glacial, the subsurface ocean during the PGM was saltier and 0.35‰ more depleted in δ13C in comparison to the LGM. Interestingly, the mean δ13C value of the PGM is comparable to the Carbon Isotope Minimum Events, which might suggests a larger contribution of "old" low δ13C deep waters to the study site during the PGM. A Latitudinal comparison of subsurface proxies suggests glacial asymmetries in the advection of SOIWs into the <span class="hlt">central</span> <span class="hlt">Pacific</span>, plausibly related to glacial changes in the convection depth of SOIWs at the South Antarctic Front area rather than changes in production of the SOIWs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19770017782','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19770017782"><span>An atlas of 1975 GEOS-3 radar altimeter data for hurricane/<span class="hlt">tropical</span> disturbance studies, volume 1</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stanley, H. R.; Chan, B.; Munson, J. R.</p> <p>1977-01-01</p> <p>Geographic locations of 1975 hurricanes and other <span class="hlt">tropical</span> disturbances were correlated with the closest approaching orbits of the GEOS-3 satellite and its radar altimeter. The disturbance locations and altimeter data were gathered for a seven-month period beginning with GEOS-3 launch in mid-April 1975. Areas of coverage were the Atlantic Ocean, the Carribean, the Gulf of Mexico, the west coast of the continental United States, and the <span class="hlt">central</span> and western <span class="hlt">Pacific</span> Ocean. Volume 1 contains disturbance coverage data for the Atlantic Ocean, Gulf of Mexico, and Eastern <span class="hlt">Pacific</span> Ocean. <span class="hlt">Central</span> and Western <span class="hlt">Pacific</span> coverage is documented in Volume II.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23885581','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23885581"><span>[Freshwater macroinvertebrates from Cocos Island, Costa Rica: species and comparison with other islands of the Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span>].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gutiérrez-Fonseca, Pablo E; Ramírez, Alonso; Umaña, Gerardo; Springer, Monika</p> <p>2013-06-01</p> <p>Freshwater macroinvertebrates from Cocos Island, Costa Rica: species and comparison with other islands of the Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span>. Cocos Island is an oceanic island in the Eastern <span class="hlt">Pacific</span>, at 496km from Cabo Blanco, Costa Rica. This 24 km2 island is surrounded by a protected marine area of 9640 km2. it was declared National Park in 1978 and a World Heritage by UNESCO in 1997. Freshwater macroinvertebrate fauna was collected in 20 sites covering three rivers (Genio, Chatam and Sucio) and two creeks (Minuto and an unnamed creek behind the park rangers' house). Tank bromeliads or phytotelmata were also examined for aquatic macroinvertebrates. Physicochemical parameters were determined in 13 study sites. Additionally, a comparison with other islands in the Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> was conducted to determine the most important factors controlling the diversity in <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> islands. A total of 455 individuals were collected belonging to 20 taxa (mostly identified to genus level) from 15 families of aquatic insects. Other macroinvertebrates such as Palaemonid shrimps, Hidrachnida and Oligochaeta were also collected. The family Staphylinidae (Coleoptera) was the most abundant, followed by Chironomidae (Diptera). Diptera was the order of insects with the highest taxonomic richness. A relationship between distance and the number of families was observed supporting the premises of the Theory of island Biogeography. This relationship was improved by correcting area by island elevation, indicating that mountainous islands had the richest faunas, potentially due to high cloud interception that feeds freshwater environments favoring the establishment of aquatic fauna. Physicochemical variables were similar in all sites, possibly due to the geology and the absence of significant sources of pollution on the island.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JASS...34..257K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JASS...34..257K"><span>Solar Influence on <span class="hlt">Tropical</span> Cyclone in Western North <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kim, Jung-Hee; Kim, Ki-Beom; Chang, Heon-Young</p> <p>2017-12-01</p> <p>Solar activity is known to be linked to changes in the Earth’s weather and climate. Nonetheless, for other types of extreme weather, such as <span class="hlt">tropical</span> cyclones (TCs), the available evidence is less conclusive. In this study the modulation of TC genesis over the western North <span class="hlt">Pacific</span> by the solar activity is investigated, in comparison with a large-scale environmental parameter, i.e., El-Niño-Southern Oscillation (ENSO). For this purpose, we have obtained the best track data for TCs in the western North <span class="hlt">Pacific</span> from 1977 to 2016, spanning from the solar cycle 21 to the solar cycle 24. We have confirmed that in the El-Niño periods TCs tend to form in the southeast, reach its maximum strength in the southeast, and end its life as TSs in the northeast, compared with the La-Niña periods. TCs occurring in the El-Niño periods are found to last longer compared with the La-Niña periods. Furthermore, TCs occurring in the El-Niño periods have a lower <span class="hlt">central</span> pressure at their maximum strength than those occurring in the La-Niña periods. We have found that TCs occurring in the solar maximum periods resemble those in the El-Niño periods in their properties. We have also found that TCs occurring in the solar descending periods somehow resemble those in the El-Niño periods in their properties. To make sure that it is not due to the ENSO effect, we have excluded TCs both in the El-Niño periods and in the La-Niña periods from the data set and repeated the analysis. In addition to this test, we have also reiterated our analysis twice with TCs whose maximum sustained winds speed exceeds 17 m/s, instead of 33 m/s, as well as TCs designated as a typhoon, which ends up with the same conclusions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFMGC54B..04A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFMGC54B..04A"><span>Weather-forced variations of <span class="hlt">Central</span> and East <span class="hlt">Pacific</span> ENSO events</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Alexander, M. A.; Newman, M.; Shin, S.</p> <p>2010-12-01</p> <p>It has been suggested that a possible outcome of climate change is an increase in the occurrence of “Modoki” or <span class="hlt">central</span> <span class="hlt">Pacific</span> El Nino events relative to canonical eastern <span class="hlt">Pacific</span> El Nino events, and that this change may already be occurring. Such a determination, however, is complicated by possible natural variations of the two types of events. How large a change in the relative occurrence can be expected from purely internal variability? To explore this question, a “patterns-based” red noise null hypothesis is constructed from 40 years of observed seasonally-averaged SST, 20 deg C thermocline depth, and surface zonal wind stress anomalies. Patterns-based (or multivariate) red noise differs from “local” (or univariate) red noise since it allows for non-local advective processes; for example, weather noise driving surface wind stress in one location to produce an ocean response in a different location. It is shown that natural random variations of the <span class="hlt">central</span> <span class="hlt">Pacific</span> to east <span class="hlt">Pacific</span> El Nino occurrence ratio are large enough that they could account for all past observed differences as well as all differences found in the SRESA1B runs of all AR4 climate models. Additionally, the correlation between Nino3 and Nino4 SST indices over 30-yr periods can range between 0.7 and 0.9 simply due to such variations in noise, with apparent multidecadal “trends” during which the value increases or decreases. Further analysis shows the different spatial patterns of “noise” (i.e., random weather forcing) that can lead to the development of <span class="hlt">central</span> vs. eastern <span class="hlt">Pacific</span> ENSO events or various combinations thereof.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_12 --> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70031476','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70031476"><span>Coral-gravel storm ridges: examples from the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> and Caribbean</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Richmond, Bruce M.; Morton, Robert A.</p> <p>2007-01-01</p> <p>Extreme storms in reef environments have long been recognized as a mechanism for depositing ridges of reef-derived coarse clastic sediment. This study revisits the storm ridges formed by <span class="hlt">Tropical</span> Cyclone Bebe on Funafuti, Tuvalu and <span class="hlt">Tropical</span> Cyclone Ofa on Upolu, Western Samoa in the South <span class="hlt">Pacific</span>, and Hurricane Lenny on Bonaire, Netherlands Antilles in the Caribbean. Ridge characteristics produced by these storms include: heights of 1–4 m, widths of 8–50 m, and lengths up to 18 km. The ridges tend to be higher and steeper on their landward margins than on their seaward margins and are composed mostly of re-worked coral rubble derived from reef front settings with smaller amounts of fresh broken coral (5–30%). Characteristics of these modern gravel storm ridges can be used to help identify ancient storm deposits and to differentiate between other coarse-grained deposits such as those created by tsunamis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012GPC....80..149W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012GPC....80..149W"><span>Climate change impacts on <span class="hlt">tropical</span> cyclones and extreme sea levels in the South <span class="hlt">Pacific</span> — A regional assessment</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Walsh, Kevin J. E.; McInnes, Kathleen L.; McBride, John L.</p> <p>2012-01-01</p> <p>This paper reviews the current understanding of the effect of climate change on extreme sea levels in the South <span class="hlt">Pacific</span> region. This region contains many locations that are vulnerable to extreme sea levels in the current climate, and projections indicate that this vulnerability will increase in the future. The recent publication of authoritative statements on the relationship between global warming and global sea level rise, <span class="hlt">tropical</span> cyclones and the El Niño-Southern Oscillation phenomenon has motivated this review. Confident predictions of global mean sea level rise are modified by regional differences in the steric (density-related) component of sea level rise and changing gravitational interactions between the ocean and the ice sheets which affect the regional distribution of the eustatic (mass-related) contribution to sea level rise. The most extreme sea levels in this region are generated by <span class="hlt">tropical</span> cyclones. The intensity of the strongest <span class="hlt">tropical</span> cyclones is likely to increase, but many climate models project a substantial decrease in <span class="hlt">tropical</span> cyclone numbers in this region, which may lead to an overall decrease in the total number of intense <span class="hlt">tropical</span> cyclones. This projection, however, needs to be better quantified using improved high-resolution climate model simulations of <span class="hlt">tropical</span> cyclones. Future changes in ENSO may lead to large regional variations in <span class="hlt">tropical</span> cyclone incidence and sea level rise, but these impacts are also not well constrained. While storm surges from <span class="hlt">tropical</span> cyclones give the largest sea level extremes in the parts of this region where they occur, other more frequent high sea level events can arise from swell generated by distant storms. Changes in wave climate are projected for the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> due to anthropogenically-forced changes in atmospheric circulation. Future changes in sea level extremes will be caused by a combination of changes in mean sea level, regional sea level trends, <span class="hlt">tropical</span> cyclone incidence and wave</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4267875','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4267875"><span>Rewilding the <span class="hlt">tropics</span>, and other conservation translocations strategies in the <span class="hlt">tropical</span> Asia-<span class="hlt">Pacific</span> region</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Louys, Julien; Corlett, Richard T; Price, Gilbert J; Hawkins, Stuart; Piper, Philip J</p> <p>2014-01-01</p> <p>Alarm over the prospects for survival of species in a rapidly changing world has encouraged discussion of translocation conservation strategies that move beyond the focus of ‘at-risk’ species. These approaches consider larger spatial and temporal scales than customary, with the aim of recreating functioning ecosystems through a combination of large-scale ecological restoration and species introductions. The term ‘rewilding’ has come to apply to this large-scale ecosystem restoration program. While reintroductions of species within their historical ranges have become standard conservation tools, introductions within known paleontological ranges—but outside historical ranges—are more controversial, as is the use of taxon substitutions for extinct species. Here, we consider possible conservation translocations for nine large-bodied taxa in <span class="hlt">tropical</span> Asia-<span class="hlt">Pacific</span>. We consider the entire spectrum of conservation translocation strategies as defined by the IUCN in addition to rewilding. The taxa considered are spread across diverse taxonomic and ecological spectra and all are listed as ‘endangered’ or ‘critically endangered’ by the IUCN in our region of study. They all have a written and fossil record that is sufficient to assess past changes in range, as well as ecological and environmental preferences, and the reasons for their decline, and they have all suffered massive range restrictions since the late Pleistocene. General principles, problems, and benefits of translocation strategies are reviewed as case studies. These allowed us to develop a conservation translocation matrix, with taxa scored for risk, benefit, and feasibility. Comparisons between taxa across this matrix indicated that orangutans, tapirs, Tasmanian devils, and perhaps tortoises are the most viable taxa for translocations. However, overall the case studies revealed a need for more data and research for all taxa, and their ecological and environmental needs. Rewilding the Asian-<span class="hlt">Pacific</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.A43D0246Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.A43D0246Z"><span>Interannual Variability of Sea Level in <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> during 1993-2014</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhu, X.; Greatbatch, R. J.; Claus, M.</p> <p>2016-12-01</p> <p>More than 40 years ago, sea level variability in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> was being studied using linear shallow water models driven by observed estimates of the surface wind stress. At that time, the only available sea level data was from the sparse tide gauge record. However, with the advent of satellite data, there has been a revolution in the available data coverage for sea level. Here, a linear model, consisting of the first five baroclinic normal modes, and driven by ERA-Interim monthly wind stress anomalies, is used to investigate interannual variability in <span class="hlt">tropical</span> <span class="hlt">Pacific</span> sea level as seen in satellite altimeter data. The model output is fitted to the altimeter data along the equator, in order to derive the vertical profile for the wind forcing, and showing that a signature from modes higher than mode six cannot be extracted from the altimeter data. It is shown that the model has considerable skill at capturing interannual sea level variability both on and off the equator. The correlation between modelled and satellite-derived sea level data exceeds 0.8 over a wide range of longitudes along the equator and readily captures the observed ENSO events. Overall, the combination of the first, second and third and fifth modes can provide a robust estimate of the interannual sea level variability, the second mode being the most dominant. A remarkable feature of both the model and the altimeter data is the presence of a pivot point in the western <span class="hlt">Pacific</span> on the equator. We show that the westward displacement of the pivot point from the centre of the basin is partly a signature of the recharge/discharge mechanism but is also strongly influenced by the fact that most of the wind stress variance along the equator is found in the western part of the basin. We also show that the Sverdrup transport plays no role in the recharge/discharge mechanism in our model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011JGRD..11620204L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011JGRD..11620204L"><span>El Niño-Southern Oscillation correlated aerosol Ångström exponent anomaly over the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> discovered in satellite measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Jing; Carlson, Barbara E.; Lacis, Andrew A.</p> <p>2011-10-01</p> <p>El Niño-Southern Oscillation (ENSO) is the dominant mode of interannual variability in the <span class="hlt">tropical</span> atmosphere. ENSO could potentially impact local and global aerosol properties through atmospheric circulation anomalies and teleconnections. By analyzing aerosol properties, including aerosol optical depth (AOD) and Ångström exponent (AE; often used as a qualitative indicator of aerosol particle size) from the Moderate Resolution Imaging Spectrometer, the Multiangle Imaging Spectroradiometer and the Sea-viewing Wide Field-of-view Sensor for the period 2000-2011, we find a strong correlation between the AE data and the multivariate ENSO index (MEI) over the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. Over the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> (WTP), AE increases during El Niño events and decreases during La Niña events, while the opposite is true over the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> (ETP). The difference between AE anomalies in the WTP and ETP has a higher correlation coefficient (>0.7) with the MEI than the individual time series and could be considered another type of ENSO index. As no significant ENSO correlation is found in AOD over the same region, the change in AE (and hence aerosol size) is likely to be associated with aerosol composition changes due to anomalous meteorological conditions induced by the ENSO. Several physical parameters or mechanisms that might be responsible for the correlation are discussed. Preliminary analysis indicates surface wind anomaly might be the major contributor, as it reduces sea-salt production and aerosol transport during El Niño events. Precipitation and cloud fraction are also found to be correlated with <span class="hlt">tropical</span> <span class="hlt">Pacific</span> AE. Possible mechanisms, including wet removal and cloud shielding effects, are considered. Variations in relative humidity, tropospheric ozone concentration, and ocean color during El Niño have been ruled out. Further investigation is needed to fully understand this AE-ENSO covariability and the underlying physical processes responsible</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUOSME24E0761D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUOSME24E0761D"><span>Three-Dimensional Distribution of Larval Fish Habitats in the Shallow Oxygen Minimum Zone in the Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Ocean off Mexico</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Davies, S.; Sanchez Velasco, L.; Beier, E.; Godinez, V. M.; Barton, E. D.; Tamayo, A.</p> <p>2016-02-01</p> <p>Three-dimensional distribution of larval fish habitats was analyzed, from the upper limit of the shallow oxygen minimum zone ( 0.2 mL/L) to the sea surface, in the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean off Mexico in February 2010.The upper limit rises from 250 m depth in the entrance of the Gulf of California to 80 m depth off Cabo Corrientes. Three larval fish habitats were defined statistically: (i) a Gulf of California habitat dominated by Anchoa spp. larvae (epipelagic species), constrained to the oxygenated surface layer (>3.5 mL/L) in and above the thermocline ( 60 m depth), and separated by a salinity front from the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> habitat; (ii) a <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> habitat, dominated by Vinciguerria lucetia larvae (mesopelagic species), located throughout the sampled water column, but with the highest abundance in the oxygenated upper layer above the thermocline; (iii) an Oxygen Minimum habitat defined mostly below the thermocline in hypoxic (<1 mL/L; 70 m depth) and anoxic (<0.2 mL/L; 80 m depth) water off Cabo Corrientes. This subsurface hypoxic habitat had the highest species richness and larval abundance, with dominance of Bregmaceros bathymaster, an endemic neritic pelagic species; which was an unexpected result. This maybe associated with the shoaling of the upper limit of the shallow oxygen minimum zone near the coast, a result of the strong costal upwelling detected by the Bakun Index. In this region of strong and semi-continuous coastal upwelling in the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> off Mexico, the shallow hypoxic water does not have dramatic effects on the total larval fish abundance but appears to affect species composition.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUFM.A13C1362A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUFM.A13C1362A"><span>Factors Influencing Aerosol Concentrations and Properties over the <span class="hlt">Tropical</span> Eastern <span class="hlt">Pacific</span>: Observations from TC4</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Anderson, B. E.; Chen, G.; Thornhill, K. L.; Winstead, E. L.; Dibb, J.; Scheuer, E.; Lathem, T.</p> <p>2007-12-01</p> <p>The NASA <span class="hlt">Tropical</span> Composition Cloud and Climate Coupling (TC4) mission was conducted during summer 2007 and had the primary objective of gaining a better understanding of composition and dynamics of the upper troposphere over the <span class="hlt">tropical</span> eastern <span class="hlt">pacific</span> region. Based in San Jose, Costa Rica, the mission employed instrumented aircraft along with ground, balloon, and satellite borne sensors to determine the spatial distribution of trace gas and aerosol species as well as moisture and clouds between the surface and roughly 16 km altitude over <span class="hlt">Central</span> America, the eastern <span class="hlt">Pacific</span>, the western Caribbean and northern South America. Because of its heavy payload and long endurance capability, the NASA DC-8 aircraft was the primary sampling platform for the lower-tropospheric altitude regime (i.e., below 12 km). It carried both remote and in situ instruments and was used to characterize cloud inflow and outflow as well as the microphysical properties of maritime convective systems. Because of their roles in regulating atmospheric radiation transfer and cloud formation and microphysics, flight plans placed particular emphasis on determining the sources and properties of the aerosol particles present within the region. A preliminary analysis of the DC-8 data set suggests that the following sources/processes had the greatest impact on aerosol number and mass loading: dust transport from Africa; sea salt production over the ocean; urban and biogenic emissions over the continent; secondary aerosol formation in volcanic plumes; nucleation in cloud outflow; and cloud scavenging. In this presentation, we will examine the microphysical, optical and hydration properties of each aerosol type and assess the overall impact of the source/sink processes to the regional aerosol budget. We will also contrast the microphysical properties of the Saharan Dust sampled over the Caribbean with those measured in fresh dust layers over the eastern Atlantic from the DC-8 during the summer 2006</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ClDy...49.1631X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ClDy...49.1631X"><span>Role of sea surface temperature anomalies in the <span class="hlt">tropical</span> Indo-<span class="hlt">Pacific</span> region in the northeast Asia severe drought in summer 2014: month-to-month perspective</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xu, Zhiqing; Fan, Ke; Wang, HuiJun</p> <p>2017-09-01</p> <p>The severe drought over northeast Asia in summer 2014 and the contribution to it by sea surface temperature (SST) anomalies in the <span class="hlt">tropical</span> Indo-<span class="hlt">Pacific</span> region were investigated from the month-to-month perspective. The severe drought was accompanied by weak lower-level summer monsoon flow and featured an obvious northward movement during summer. The mid-latitude Asian summer (MAS) pattern and East Asia/<span class="hlt">Pacific</span> teleconnection (EAP) pattern, induced by the Indian summer monsoon (ISM) and western North <span class="hlt">Pacific</span> summer monsoon (WNPSM) rainfall anomalies respectively, were two main bridges between the SST anomalies in the <span class="hlt">tropical</span> Indo-<span class="hlt">Pacific</span> region and the severe drought. Warming in the Arabian Sea induced reduced rainfall over northeast India and then triggered a negative MAS pattern favoring the severe drought in June 2014. In July 2014, warming in the <span class="hlt">tropical</span> western North <span class="hlt">Pacific</span> led to a strong WNPSM and increased rainfall over the Philippine Sea, triggering a positive EAP pattern. The equatorial eastern <span class="hlt">Pacific</span> and local warming resulted in increased rainfall over the off-equatorial western <span class="hlt">Pacific</span> and triggered an EAP-like pattern. The EAP pattern and EAP-like pattern contributed to the severe drought in July 2014. A negative Indian Ocean dipole induced an anomalous meridional circulation, and warming in the equatorial eastern <span class="hlt">Pacific</span> induced an anomalous zonal circulation, in August 2014. The two anomalous cells led to a weak ISM and WNPSM, triggering the negative MAS and EAP patterns responsible for the severe drought. Two possible reasons for the northward movement of the drought were also proposed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.A21B0034B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.A21B0034B"><span>Interactive influence of the Atlantic and <span class="hlt">Pacific</span> climates and their contribution to the multidecadal variations of global temperature and precipitation.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Barcikowska, M. J.; Knutson, T. R.; Zhang, R.</p> <p>2016-12-01</p> <p>This study investigates mechanisms and global-scale climate impacts of multidecadal climate variability. Here we show, using observations and CSIRO-Mk3.6.0 model control run, that multidecadal variability of the Atlantic Meridional Overturning Circulation (AMOC) may have a profound impact on the thermal- and hydro-climatic changes over the <span class="hlt">Pacific</span> region. In our model-based analysis we propose a mechanism, which comprises a coupled ocean-atmosphere teleconnection, established through the atmospheric overturning circulation cell between the <span class="hlt">tropical</span> North Atlantic and <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. For example, warming SSTs over the <span class="hlt">tropical</span> North Atlantic intensify local convection and reinforce subsidence, low-level divergence in the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. This is also accompanied with an intensification of trade winds, cooling and drying anomalies in the <span class="hlt">tropical</span> <span class="hlt">central</span>-east <span class="hlt">Pacific</span>. The derived multidecadal changes, associated with the AMOC, contribute remarkably to the global temperature and precipitation variations. This highlights its potential predictive value. Shown here results suggest a possibility that: 1) recently observed slowdown in global warming may partly originate from internal variability, 2) climate system may be undergoing a transition to a cold AMO phase which could prolong the global slowdown.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/FR-2012-02-24/pdf/2012-4300.pdf','FEDREG'); return false;" href="https://www.gpo.gov/fdsys/pkg/FR-2012-02-24/pdf/2012-4300.pdf"><span>77 FR 11192 - Cedar River Railroad Company-Trackage Rights Exemption-Chicago, <span class="hlt">Central</span> & <span class="hlt">Pacific</span> Railroad Company</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR">Federal Register 2010, 2011, 2012, 2013, 2014</a></p> <p></p> <p>2012-02-24</p> <p>... Railroad Company--Trackage Rights Exemption--Chicago, <span class="hlt">Central</span> & <span class="hlt">Pacific</span> Railroad Company Pursuant to a written trackage rights agreement,\\1\\ Chicago, <span class="hlt">Central</span> & <span class="hlt">Pacific</span> Railroad Company (CCP) has agreed to grant nonexclusive overhead trackage rights to Cedar River Railroad Company (CEDR) over approximately 5...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMEP23B0964B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMEP23B0964B"><span>ENSO-Related Variability in Wave Climate Drives Greater Erosion Potential on <span class="hlt">Central</span> <span class="hlt">Pacific</span> Atolls</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bramante, J. F.; Ashton, A. D.; Donnelly, J. P.</p> <p>2015-12-01</p> <p>The El Nino Southern Oscillation (ENSO) modulates atmospheric circulation across the equatorial <span class="hlt">Pacific</span> over a periodic time scale of 2-7 years. Despite the importance of this climate mode in forcing storm generation and trade wind variability, its impact on the wave climate incident on <span class="hlt">central</span> <span class="hlt">Pacific</span> atolls has not been addressed. We used the NOAA Wavewatch III CFSR reanalysis hindcasts (1979-2007) to examine the influence of ENSO on sediment mobility and transport at Kwajalein Atoll (8.8°N, 167.7°E). We found that during El Nino event years, easterly trade winds incident on the atoll weakened by 4% compared to normal years and 17% relative to La Nina event years. Despite this decrease in wind strength, significant wave heights incident on the atoll were 3-4% greater during El Nino event years. Using machine learning to partition these waves revealed that the greater El Nino wave heights originated mainly from greater storm winds near the atoll. The southeastern shift in <span class="hlt">tropical</span> cyclone genesis location during El Nino years forced these storm winds and contributed to the 7% and 16% increases in annual wave energy relative to normal and La Nina years, respectively. Using nested SWAN and XBeach models we determined that the additional wave energy during El Nino event years significantly increased potential sediment mobility at Kwajalein Atoll and led to greater net offshore transport on its most populous island. The larger storm waves likely deplete ocean-facing beaches and reef flats of sediment, but increase the supply of sediment to the atoll lagoon across open reef platforms that are not supporting islands. We discuss further explicit modelling of storms passing over the atoll to elucidate the confounding role of storm surge on the net erosional/depositional effects of these waves. Extrapolating our results to recent Wavewatch III forecasts leads us to conclude that climate change-linked increases in wave height and storm wave energy will increase erosion on</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013CorRe..32..553S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013CorRe..32..553S"><span>Soundscapes from a <span class="hlt">Tropical</span> Eastern <span class="hlt">Pacific</span> reef and a Caribbean Sea reef</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Staaterman, E.; Rice, A. N.; Mann, D. A.; Paris, C. B.</p> <p>2013-06-01</p> <p>Underwater soundscapes vary due to the abiotic and biological components of the habitat. We quantitatively characterized the acoustic environments of two coral reef habitats, one in the <span class="hlt">Tropical</span> Eastern <span class="hlt">Pacific</span> (Panama) and one in the Caribbean (Florida Keys), over 2-day recording durations in July 2011. We examined the frequency distribution, temporal variability, and biological patterns of sound production and found clear differences. The <span class="hlt">Pacific</span> reef exhibited clear biological patterns and high temporal variability, such as the onset of snapping shrimp noise at night, as well as a 400-Hz daytime band likely produced by damselfish. In contrast, the Caribbean reef had high sound levels in the lowest frequencies, but lacked clear temporal patterns. We suggest that acoustic measures are an important element to include in reef monitoring programs, as the acoustic environment plays an important role in the ecology of reef organisms at multiple life-history stages.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMPP41B1356B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMPP41B1356B"><span>Holocene Evolution of Precipitation Patterns in the Southwestern US, Mexico, <span class="hlt">Central</span> America, and Caribbean: Comparison with <span class="hlt">Tropical</span> SST Records</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Barron, J. A.; Metcalfe, S. E.; Davies, S. J.</p> <p>2014-12-01</p> <p>We evaluate proxy reconstructions of Holocene records precipitation in the North American Monsoon region (SW US and northern Mexico) and regions to the south (southern Mexico, <span class="hlt">Central</span> America, and the Caribbean). Seventy-seven precipitation records are tabulated at 2-3 kyr increments for the past 12 kyr, with results displayed mainly on maps. Sites currently dominated by summer precipitation, coupled with proxy records that distinguish summer vs. winter vegetation are used to estimate summer precipitation. Resulting patterns of precipitation variability are evaluated against SST reconstructions from surrounding <span class="hlt">tropical</span> seas -eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, Gulf of California (GoC), Caribbean, and Gulf of Mexico (GoM), which are source areas for summer precipitation. During the Younger Dryas, ca. 12 ka, widespread drying in southern regions contrasted with evidence for wetter conditions in multiple records from the SW US. By 9 ka wetter conditions had spread to the southern regions, likely reflecting an increased Caribbean low-level jet associated with an enhanced Bermuda High. <span class="hlt">Pacific</span> westerlies contributed significant winter precipitation to the southwestern US and northernmost Mexico at 9 ka. The modern geographical pattern of summer precipitation was established by 6 ka, as the Bermuda High moved northward following the demise of the Laurentide Ice Sheet. SSTs in the GoC and GoM increased, and the NAM strengthened. Increased regional precipitation differences are apparent by 4 ka, likely reflecting enhanced ENSO variability. Most of the southern region experienced increased precipitation during the Medieval Climate Anomaly (MCA), whereas winter drought dominated in the north. In contrast, much of the Little Ice Age (LIA) was characterized by generally drier conditions in <span class="hlt">Central</span> America and Mexico, with wetter conditions in the SW US. Results are broadly supportive of enhanced La Niña-like conditions during the MCA vs. increased ENSO variability during the LIA.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMPP51D2329S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMPP51D2329S"><span>Coral Ensemble Estimates of <span class="hlt">Central</span> <span class="hlt">Pacific</span> Mean Climate During the Little Ice Age</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sayani, H. R.; Cobb, K. M.; O'Connor, G.; Khare, A.; Atwood, A. R.; Grothe, P. R.; Chen, T.; Hagos, M. M.; Hitt, N. T.; Thompson, D. M.; Deocampo, D.; Lu, Y.; Cheng, H.; Edwards, R. L.</p> <p>2016-12-01</p> <p>Multi-century, robust records of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> sea-surface temperature (SST) and salinity (SSS) variability from the pre-industrial era are needed to quantify anthropogenic contributions to present-day climate trends and to improve the accuracy of regional climate projections. However, high-resolution reconstructions of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> climate are scarce prior to the 20th century, and only a handful exist from the Little Ice Age (LIA, 1500-1850CE) immediately prior to the documented rise of anthropogenic greenhouse gases. Modern and fossil corals from the northern Line Islands (2-6°N, 157-162°W) have been used to extend the instrumental climate record back into the LIA and beyond, primarily for paleo-ENSO investigations [Cobb et al., 2003, 2013]. However, large offsets in mean coral Sr/Ca and δ18O values observed across overlapping coral colonies translate into 1-2°C (1σ) uncertainties for mean climate reconstructions based on any single fossil coral colony. Here we present the results of a new approach to reconstructing mean climate during the LIA using a large ensemble (N>10) of relatively short (7-15yr long), U/Th-dated fossil corals from Christmas Island (2°N, 157°W). We employ pseudo-coral estimates of paleo-SST and paleo-seawater δ18O variations as benchmarks for our reconstructions, with a focus on quantifying the maximum and minimum potential <span class="hlt">tropical</span> <span class="hlt">Pacific</span> SST changes during the LIA that are consistent with our new ensemble of coral data. Lastly, by comparing bulk and high-resolution coral d18O and Sr/Ca records, we identify the strengths and limitations of using a high-N, ensemble approach to climate reconstruction from fossil corals. References:Cobb, K. M., et al. (2003) Nature. doi:10.1038/nature01779Cobb, K. M., et al. (2013) Science. doi: 10.1126/science.1228246</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.A12H..07Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.A12H..07Z"><span>Impacts of <span class="hlt">Tropical</span> North Atlantic SST on Western North <span class="hlt">Pacific</span> Landfalling <span class="hlt">Tropical</span> Cyclones</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, W.; Gao, S.; Chen, Z.</p> <p>2017-12-01</p> <p>This study examines the impacts of <span class="hlt">tropical</span> North Atlantic (TNA) sea surface temperature (SST) anomaly (SSTA) on <span class="hlt">tropical</span> cyclones (TCs) making landfall over East Asia. We find that TNA SSTA has significant negative correlations with the frequency of TCs making landfall over China, Vietnam, Korea and Japan, and the entire East Asia. TNA SST influences the frequency of TC landfalls over these regions by regulating TC genesis location and frequency and steering flow associated with modulated environmental conditions. During cold TNA SST years, larger low-level relative vorticity and weaker vertical wind shear lead to more TC formations in the northern SCS and to the east of Philippines, and larger low-level relative vorticity, higher mid-level relative humidity, and weaker vertical wind shear result in more TC formations over the eastern part of WNP. Anomalous northeasterly steering flow favors more TCs to move westward or west-northwestward and make landfall over Vietnam, South China and Taiwan Island and thus in the entire China, and more TCs take regular northeastward recurving tracks and make landfall over Korea and Japan because of insignificant steering flow anomalies in the vicinity. The modulation of large-scale environments by TNA SSTA may be through two possible pathways proposed in previous studies, i.e., Indian Ocean relaying effect and subtropical eastern <span class="hlt">Pacific</span> relaying effect. Our results suggest that TNA SSTA is a potential predictor for the frequency of TCs making landfall over China, Vietnam, Korea and Japan, and the entire East Asia.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29206219','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29206219"><span>Long-term monitoring of coral reef fish assemblages in the Western <span class="hlt">central</span> <span class="hlt">pacific</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Heenan, Adel; Williams, Ivor D; Acoba, Tomoko; DesRochers, Annette; Kosaki, Randall K; Kanemura, Troy; Nadon, Marc O; Brainard, Russell E</p> <p>2017-12-05</p> <p>Throughout the <span class="hlt">tropics</span>, coral reef ecosystems, which are critically important to people, have been greatly altered by humans. Differentiating human impacts from natural drivers of ecosystem state is essential to effective management. Here we present a dataset from a large-scale monitoring program that surveys coral reef fish assemblages and habitats encompassing the bulk of the US-affiliated <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, and spanning wide gradients in both natural drivers and human impact. Currently, this includes >5,500 surveys from 39 islands and atolls in Hawaii (including the main and Northwestern Hawaiian Islands) and affiliated geo-political regions of American Samoa, the Commonwealth of the Northern Mariana Islands, Guam, and the <span class="hlt">Pacific</span> Remote Islands Areas. The dataset spans 2010-2017, during which time, each region was visited at least every three years, and ~500-1,000 surveys performed annually. This standardised dataset is a powerful resource that can be used to understand how human, environmental and oceanographic conditions influence coral reef fish community structure and function, providing a basis for research to support effective management outcomes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5716063','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5716063"><span>Long-term monitoring of coral reef fish assemblages in the Western <span class="hlt">central</span> <span class="hlt">pacific</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Heenan, Adel; Williams, Ivor D.; Acoba, Tomoko; DesRochers, Annette; Kosaki, Randall K.; Kanemura, Troy; Nadon, Marc O.; Brainard, Russell E.</p> <p>2017-01-01</p> <p>Throughout the <span class="hlt">tropics</span>, coral reef ecosystems, which are critically important to people, have been greatly altered by humans. Differentiating human impacts from natural drivers of ecosystem state is essential to effective management. Here we present a dataset from a large-scale monitoring program that surveys coral reef fish assemblages and habitats encompassing the bulk of the US-affiliated <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, and spanning wide gradients in both natural drivers and human impact. Currently, this includes >5,500 surveys from 39 islands and atolls in Hawaii (including the main and Northwestern Hawaiian Islands) and affiliated geo-political regions of American Samoa, the Commonwealth of the Northern Mariana Islands, Guam, and the <span class="hlt">Pacific</span> Remote Islands Areas. The dataset spans 2010–2017, during which time, each region was visited at least every three years, and ~500–1,000 surveys performed annually. This standardised dataset is a powerful resource that can be used to understand how human, environmental and oceanographic conditions influence coral reef fish community structure and function, providing a basis for research to support effective management outcomes. PMID:29206219</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012DyAtO..57....1C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012DyAtO..57....1C"><span>Influence of the Western <span class="hlt">Pacific</span> teleconnection pattern on Western North <span class="hlt">Pacific</span> <span class="hlt">tropical</span> cyclone activity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Choi, Ki-Seon; Moon, Il-Ju</p> <p>2012-09-01</p> <p>This study analyzes the characteristics of Western North <span class="hlt">Pacific</span> (WNP) <span class="hlt">tropical</span> cyclone (TC) activity and large-scale environments according to the Western <span class="hlt">Pacific</span> (WP) teleconnection pattern in summer. In the positive WP phase, an anomalous cyclone and an anomalous anticyclone develop in the low and middle latitudes of the East Asia area, respectively. As a result, southeasterlies are reinforced in the northeast area of East Asia (including Korea and Japan), which facilitates the movement of TC to this area, whereas northwesterlies are reinforced in the southwest area of East Asia (including southern China and the Indochina Peninsula) which blocks the movement of TC to that area. Due to the spatial distribution of this reinforced pressure system, TCs that develop during the positive WP phase move and turn more to the northeast of the WNP than TCs which develop during the negative WP phase. The characteristics of this TC activity during the positive WP phase are associated with the upper tropospheric jet being located farther to the northeast. TCs during the negative WP phase mainly move to the west from the Philippines toward southern China and the Indochina Peninsula. Due to the terrain effect caused by the passage of TCs in mainland China, the intensity of TCs during the negative WP phase is weaker than those during the positive WP phase.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19800043104&hterms=nitrous+oxide&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dnitrous%2Boxide','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19800043104&hterms=nitrous+oxide&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dnitrous%2Boxide"><span>Nitrous oxide measurements in the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Pierotti, D.; Rasmussen, R. A.</p> <p>1980-01-01</p> <p>The paper considers nitrous oxide measurements in the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean. The concentration of N2O in the marine air showed a direct relationship to the N2O in the surface sea water, with the highest N2O mixing ratios over highly supersaturated regions; water samples were also collected down to depths of 300 m at seven hydrocast stations. The stations showed two distribution patterns for N2O concentration vs depth for the region between the surface and 300 m; two stations in the oxygen deficient region off the coast of Peru showed considerable N2O super-saturation at all depths, and results indicate that the role of N2O in the nitrogen cycle of the ocean may be more complex than previously suggested.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JGRD..123...89C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JGRD..123...89C"><span>Autumn Cooling of Western East Antarctica Linked to the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Clem, Kyle R.; Renwick, James A.; McGregor, James</p> <p>2018-01-01</p> <p>Over the past 60 years, the climate of East Antarctica cooled while portions of West Antarctica were among the most rapidly warming regions on the planet. The East Antarctic cooling is attributed to a positive trend in the Southern Annular Mode (SAM) and a strengthening of the westerlies, while West Antarctic warming is tied to zonally asymmetric circulation changes forced by the <span class="hlt">tropics</span>. This study finds recent (post-1979) surface cooling of East Antarctica during austral autumn to also be tied to <span class="hlt">tropical</span> forcing, namely, an increase in La Niña events. The recent increase in La Niña conditions forces a Rossby wave into the Southern Hemisphere that increases anticyclonic circulation over the South Atlantic. The South Atlantic anticyclone is associated with cold air advection, weakened northerlies, and increased sea ice concentrations across the western East Antarctic coast, which has increased the rate of cooling at Novolazarevskaya and Syowa stations after 1979. This enhanced cooling over western East Antarctica is tied more broadly to a zonally asymmetric temperature trend pattern across East Antarctica during autumn that is consistent with a <span class="hlt">tropically</span> forced Rossby wave rather than a SAM pattern; the positive SAM pattern is associated with ubiquitous cooling across East Antarctica, which is not seen in temperature observations after 1979. We conclude that El Niño-Southern Oscillation-related circulation anomalies, particularly zonal asymmetries that locally enhance meridional wind, are an important component of East Antarctic climate variability during autumn, and future changes in <span class="hlt">tropical</span> <span class="hlt">Pacific</span> climate will likely have implications for East Antarctica.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3286223','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3286223"><span>Review of the Capitellidae (Annelida, Polychaeta) from the Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> region, with notes on selected species</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>García-Garza, María Elena; León-González, Jesús Angel De</p> <p>2011-01-01</p> <p>Abstract The main objective of this work is to contribute to the taxonomic knowledge of the species of Capitellidae reported for the Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span>. This catalogue includes the original name of each species, new names, synonymies, type localities, the museum or institution where the type material is deposited, revision of the material reported for the region by different authors, new examined material, previous reports from other regions of the world, and comments on systematics and distributions. The catalogue lists 43 species in 19 genera. Of these, 6 species were erroneously recorded for the region (Decamastus gracilis Hartman, 1963; Decamastus nudus Thomassin, 1970; Mastobranchus variabilis Edwing, 1984; Notomastus aberans Day, 1957; Notomastus americanus Day, 1973; Notomastus latericeus Sars, 1851) and 5 species are found here to be questionable records for the Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> (Capitella capitata (Fabricius, 1780); Dasybranchus glabrus Moore, 1909; Decamastus lumbricoides Grube, 1878; Notomastus lineatus Claparède, 1870 and Notomastus tenuis Moore, 1909). PMID:22368451</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMOS51A2020S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMOS51A2020S"><span>Distribution and Magnitude of Dinitrogen Fixation in the Eastern <span class="hlt">Tropical</span> North <span class="hlt">Pacific</span> Oxygen Deficient Zone.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Selden, C.; Mulholland, M. R.; Widner, B.; Bernhardt, P. W.; Macías Tapia, A.; Jayakumar, A.</p> <p>2016-12-01</p> <p>The Eastern <span class="hlt">Tropical</span> North <span class="hlt">Pacific</span> Ocean (ETNP) hosts one of the world's three major open ocean oxygen deficient zones (ODZs). Hotspots for fixed nitrogen (N) loss processes, ODZs have classically been discounted as areas of significant dinitrogen (N2) fixation, the microbe-mediated reduction of N2 to ammonium (NH4+), which has historically been ascribed primarily to euphotic, nutrient-deplete <span class="hlt">tropical</span> waters. Challenging this paradigm, active expression of nifH (the dinitrogen reductase structural gene) has recently been documented in the ETNP, Eastern <span class="hlt">Tropical</span> South <span class="hlt">Pacific</span>, and Arabian Sea ODZs, implying a closer coupling of fixed nitrogen input and loss processes than previously thought. Here, we report rates of N2 fixation measured in the ETNP ODZ along vertical gradients of oxygen, light, and dissolved N concentrations. Detailed vertical profiles of N2 fixation rates and dissolved N concentrations made within the ODZ were compared with similar profiles from oxic waters outside the ODZ. In addition, different organic carbon sources were investigated as potential rate-limiting factors for N2 fixation in sub-euphotic waters. By establishing the magnitude and distribution of N2 fixation in the ETNP ODZ, this study contributes to current understanding of N cycling in anoxic and aphotic waters, and serves to elucidate nuances in the global N budget, enabling more accurate biogeochemical modeling. Understanding these processes in present day ODZs is crucial for predicting how ongoing anthropogenic intensification of coastal ODZs will alter biogeochemical cycles in the future.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70159418','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70159418"><span>Deep divergence and structure in the <span class="hlt">Tropical</span> Oceanic <span class="hlt">Pacific</span>: a multilocus phylogeography of a widespread gekkonid lizard (Squamata: Gekkonidae: Gehyra oceanica)</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Tonione, Maria A.; Fisher, Robert N.; Zhu, Catherine; Moritz, Craig</p> <p>2016-01-01</p> <p>Aim The islands of the <span class="hlt">Tropical</span> Oceanic <span class="hlt">Pacific</span> (TOP) host both local radiations and widespread, colonizing species. The few phylogeographical analyses of widespread species often point to recent human-aided expansions through the <span class="hlt">Pacific</span>, suggesting that the communities are recently assembled. Here we apply multilocus data to infer biogeographical history of the gekkonid lizard, Gehyra oceanica, which is widespread, but for which prior analyses suggested a pre-human history and in situ diversification. Location <span class="hlt">Tropical</span> Oceanic <span class="hlt">Pacific</span>. Methods We generated a data set including mtDNA and diagnostic SNPs for 173 individuals of G. oceanica spanning Micronesia, Melanesia, and Polynesia. For a subset of these individuals, we also sequenced nuclear loci. From these data, we performed maximum likelihood and Bayesian inference to reveal major clades. We also performed Bayesian clustering analyses and coalescence–based species delimitation tests to infer the number of species in this area. Results We found evidence for six independent evolutionary lineages (candidate species) within G. oceanica that diverged between the Pliocene and the early Pleistocene, with high diversity through northern Melanesia, and pairing of northern Melanesian endemic taxa with widespread lineages across Micronesia and Polynesia. Main conclusions The islands of northern Melanesia not only have unrecognized diversity, but also were the source of independent expansions of lineages through the more remote northern and eastern <span class="hlt">Pacific</span>. These results highlight the very different evolutionary histories of island faunas on remote archipelagos versus those across Melanesia and point to the need for more intensive studies of fauna within Melanesia if we are to understand the evolution of diversity across the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017GBioC..31.1454K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017GBioC..31.1454K"><span>Distribution of Dissolved Zinc in the Western and <span class="hlt">Central</span> Subarctic North <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kim, Taejin; Obata, Hajime; Nishioka, Jun; Gamo, Toshitaka</p> <p>2017-09-01</p> <p>We investigated the biogeochemical cycling of dissolved zinc (Zn) in the western and <span class="hlt">central</span> subarctic North <span class="hlt">Pacific</span> during the GEOTRACES GP 02 cruise. The relationship between dissolved Zn and silicate in the subarctic North <span class="hlt">Pacific</span> plotted as a concave curve. Values of Zn* were strongly positive in the intermediate waters (26.6-27.5 σθ) of both the western and the <span class="hlt">central</span> subarctic North <span class="hlt">Pacific</span>. There was a distinct kink in the relationship between dissolved Zn and soluble reactive phosphorus (SRP) at the transition from shallow to intermediate water, which is similar to what has been reported for other open oceans. The high Zn:SRP ratio and high Zn* in the intermediate water suggest that intermediate water masses play an important role in the decoupling of dissolved Zn and silicate in the subarctic North <span class="hlt">Pacific</span>, which implies that the biogeochemical processes that control dissolved Zn and silicate in the intermediate water are different from those in other oceanic regions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.A33L3369K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.A33L3369K"><span>Possible relationship between East Indian Ocean SST and <span class="hlt">tropical</span> cyclone affecting Korea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kim, J. Y.; Choi, K. S.; Kim, B. J.</p> <p>2014-12-01</p> <p>In this study, a strong negative correlation was found between East Indian Ocean (EIO) SST and frequency of summertime <span class="hlt">tropical</span> cyclone (TC) affecting Korea.For the Warm EIO SST years, the TCs mostly occurred in the southwestern region of <span class="hlt">tropical</span> and subtropical western <span class="hlt">Pacific</span>, and migrated west toward the southern coast of China and Indochinese peninsula through the South China Sea. This is because the anomalous easterlies, induced by the development of anomalous anticyclone (weakening of monsoon trough) from the <span class="hlt">tropical</span> <span class="hlt">central</span> <span class="hlt">Pacific</span> to the southern coast of China, served as the steering flows for the westward migration of TCs. In contrast, for the cold EIO SST years, the TCs mostly occurred in the northeastern region of <span class="hlt">tropical</span> and subtropical western <span class="hlt">Pacific</span>, and migrated toward Korea and Japan located in the mid-latitudes of East Asia through the East China Sea. This is because the northeastward retreat of subtropical western North <span class="hlt">Pacific</span> high (SWNPH) was more distinct for the cold EIO SST years compared to the warm EIO SST years. Therefore, the TCs of warm EIO SST years weakened or dissipated shortly due to the effect of geographical features as they land on the southern coast of China and Indochinese peninsula, whereas the TCs of cold EIO SST years had stronger intensity than the TCs of warm EIO SST years as sufficient energy is supplied from the ocean while moving toward Korea and Japan.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28854201','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28854201"><span>Association of whale sharks (Rhincodon typus) with thermo-biological frontal systems of the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ryan, John P; Green, Jonathan R; Espinoza, Eduardo; Hearn, Alex R</p> <p>2017-01-01</p> <p>Satellite tracking of 27 whale sharks in the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, examined in relation to environmental data, indicates preferential occupancy of thermo-biological frontal systems. In these systems, thermal gradients are caused by wind-forced circulation and mixing, and biological gradients are caused by associated nutrient enrichment and enhanced primary productivity. Two of the frontal systems result from upwelling, driven by divergence in the current systems along the equator and the west coast of South America; the third results from wind jet dynamics off <span class="hlt">Central</span> America. All whale sharks were tagged near Darwin Island, Galápagos, within the equatorial <span class="hlt">Pacific</span> upwelling system. Occupancy of frontal habitat is pronounced in synoptic patterns of shark locations in relation to serpentine, temporally varying thermal fronts across a zonal expanse > 4000 km. 80% of shark positions in northern equatorial upwelling habitat and 100% of positions in eastern boundary upwelling habitat were located within the upwelling front. Analysis of equatorial shark locations relative to thermal gradients reveals occupancy of a transition point in environmental stability. Equatorial subsurface tag data show residence in shallow, warm (>22°C) water 94% of the time. Surface zonal current speeds for all equatorial tracking explain only 16% of the variance in shark zonal movement speeds, indicating that passive drifting is not a primary determinant of movement patterns. Movement from equatorial to eastern boundary frontal zones occurred during boreal winter, when equatorial upwelling weakens seasonally. Off Peru sharks tracked upwelling frontal positions within ~100-350 km from the coast. Off <span class="hlt">Central</span> America, the largest tagged shark (12.8 m TL) occupied an oceanic front along the periphery of the Panama wind jet. Seasonal movement from waning equatorial upwelling to productive eastern boundary habitat is consistent with underlying trophic dynamics. Persistent shallow residence in</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018AcO....88...71H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018AcO....88...71H"><span>Gibbons (Nomascus gabriellae) provide key seed dispersal for the <span class="hlt">Pacific</span> walnut (Dracontomelon dao), in Asia's lowland <span class="hlt">tropical</span> forest</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hai, Bach Thanh; Chen, Jin; McConkey, Kim R.; Dayananda, Salindra K.</p> <p>2018-04-01</p> <p>Understanding the mutualisms between frugivores and plants is essential for developing successful forest management and conservation strategies, especially in <span class="hlt">tropical</span> rainforests where the majority of plants are dispersed by animals. Gibbons are among the most effective seed dispersers in South East Asia's <span class="hlt">tropical</span> forests, but are also one of the highly threatened arboreal mammals in the region. Here we studied the seed dispersal of the <span class="hlt">Pacific</span> walnut (Dracontomelon dao), a canopy tree which produces fruit that are common in the diet of the endangered southern yellow-cheeked crested gibbon (Nomascus gabriellae). We found that gibbons were the most effective disperser for this species; they consumed approximately 45% of the fruit crop, which was four times more than that consumed by macaques - the only other legitimate disperser. Gibbons tracked the temporal (but not spatial) abundance of ripe fruits, indicating this fruit was a preferred species for the gibbon. Both gibbons and macaques dispersed the majority (>90%) of the seeds at least 20 m away from parent crowns, with mean dispersal distances by gibbons measuring 179.3 ± 98.0 m (range: 4-425 m). Seeds defecated by gibbons germinated quicker and at greater rates than seeds spat by macaques, or in undispersed fruits. Gibbon-dispersed seeds were also more likely to be removed by unknown seed predators or unknown secondary dispersers. Overall, gibbons play a key role in the regeneration of the <span class="hlt">Pacific</span> walnut. Our findings have significant implications both for the management of the <span class="hlt">Pacific</span> walnut tree dominating <span class="hlt">tropical</span> rainforest as well as the reintroduction program of the Southern yellow-cheeked crested gibbon.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19890035218&hterms=Wave+Energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DWave%2BEnergy','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19890035218&hterms=Wave+Energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DWave%2BEnergy"><span>An estimate of equatorial wave energy flux at 9- to 90-day periods in the <span class="hlt">Central</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Eriksen, Charles C.; Richman, James G.</p> <p>1988-01-01</p> <p>Deep fluctuations in current along the equator in the <span class="hlt">Central</span> <span class="hlt">Pacific</span> are dominated by coherent structures which correspond closely to narrow-band propagating equatorial waves. Currents were measured roughly at 1500 and 3000 m depths at five moorings between 144 and 148 deg W from January 1981 to March 1983, as part of the <span class="hlt">Pacific</span> Equatorial Ocean Dynamics program. In each frequency band resolved, a single complex empirical orthogonal function accounts for half to three quarters of the observed variance in either zonal or meridional current. Dispersion for equatorial first meridional Rossby and Rossby gravity waves is consistent with the observed vertical-zonal coherence structure. The observations indicate that energy flux is westward and downward in long first meridional mode Rossby waves at periods 45 days and longer, and eastward and downward in short first meridional mode Rossby waves and Rossby-gravity waves at periods 30 days and shorter. A local minimum in energy flux occurs at periods corresponding to a maximum in upper-ocean meridional current energy contributed by <span class="hlt">tropical</span> instability waves. Total vertical flux across the 9- to 90-day period range is 2.5 kW/m.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFMPP41A1417A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFMPP41A1417A"><span>Oxygen Isotope Composition of Phytoliths From Australian <span class="hlt">Tropical</span> Forests: Towards a New Paleoclimate Tool for the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> area</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Alexandre, A.; Crespin, J.; Sonzogni, C.; Sylvestre, F.; Hilbert, D.</p> <p>2008-12-01</p> <p>Obtaining new continental δ18Ophytolith records from the <span class="hlt">tropical</span> <span class="hlt">pacific</span> area would help to further investigate 1) synchronicity between vegetation and climate changes, and 2) climate interactions between ocean and continent through comparison with oceanic reference δ18O records. In this aim, we produce a calibration of the thermo-dependant relationship between δ18Ophytolith and δ18Orainfall for present phytolith assemblages from Queensland rainforests (Australia). Phytoliths were extracted from soil humic horizons sampled along several elevation, temperature and rainfall gradients. Phytolith samples of 1.6mg were analyzed using a newly calibrated IR-laser fluorination technique, performed after a controlled isotopic exchanged procedure. The long term reproducibility on δ18O measurements is < ±0.5‰ (1SD), that leads to an estimated uncertainty on δ18Ophytolith close to ±0.5‰ and fit in the precision required for inter-<span class="hlt">tropical</span> paleo-environmental reconstructions. Globular granulate phytoliths, produced in the secondary xylem of dicots, account from 60 to 90% of the phytolith assemblages. As transpiration is non-significant in the wood, δ18Owood sap should equal to δ18Osoil water. Moreover, because relative humidity is close to 100%, soil evaporation is weak and δ18Osoil water is assumed to be similar to δ18Orainfall. The obtained thermo-dependant relationship between δ18Ophytolith and δ18O mean monthly rainfall of the wet season (r=0.68) is close to the equilibrium fractionation equations obtained for quartz and diatoms. Effects of forest fires on phytoliths dehydration and δ18Ophytolith are tested through heating experiments. Provided that phytolith assemblages present a morphological <span class="hlt">tropical</span> forest pattern, δ18Ophytolith records from sediments can now be interpreted in term of δ18Osoil water, or δ18Orainfall (provided that no soil evaporation is assumed), and temperature changes. This is a first step in further investigating synchronicity</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AGUFMPP43A1210K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AGUFMPP43A1210K"><span>Holocene East Asian Monsoon Variability: Links to Solar and <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Forcing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kandasamy, S.; Chen, C. A.; Lou, J.</p> <p>2006-12-01</p> <p>Sedimentary geochemical records from subalpine Retreat Lake, subtropical Taiwan, document the unstable East Asian Monsoon (EAM) climate for the last ~10250 calendar years before the present (cal yr B.P.). The proxy records demonstrate cool, glacial conditions with weak EAM between ~10250 and 8640 cal yr B.P., the strongest EAM during the "Holocene optimum" (8640-4500 cal yr B.P.) with an abrupt, decadal onset of postglacial EAM (8640-8600 cal yr B.P.), and relatively dry conditions since 4500 cal yr B.P. Although after 8600 cal yr B.P., EAM strength reduces gradually in response to the Northern Hemisphere summer insolation, heat and moisture transport and the development of late Holocene El-Niño-Southern Oscillation in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> appear to corroborate the periods of abrupt monsoon changes. Our proxy records reveal several weak monsoon intervals that correlate to low sea surface temperatures in the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> and cold events in the North Atlantic, suggesting a mechanistic link. Among those, four weak EAM events at 8170, 5400, 4500-2100 and 2000-1600 cal yr B.P. are in phase with the timings of low concentrations of atmospheric methane and periods of reduced North Atlantic Deep Water production as well as the `8.2 ka cold spell' and widespread event of low-latitude cultural collapse. Our EAM records exhibit strong correlations with high- and low-latitude climate and monsoon records; thus, provide robust evidences that the centennial-millennial scale monsoon variability during the Holocene are globally-mediated via sun- ocean-monsoon-North Atlantic linkages.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JGRC..118.2367C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JGRC..118.2367C"><span>Observed near-surface flows under all <span class="hlt">tropical</span> cyclone intensity levels using drifters in the northwestern <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chang, Yu-Chia; Chen, Guan-Yu; Tseng, Ruo-Shan; Centurioni, Luca R.; Chu, Peter C.</p> <p>2013-05-01</p> <p>Data from drifters of the surface velocity program and <span class="hlt">tropical</span> cyclones (TCs) of the Joint Typhoon Warning Center during 1985-2009 were analyzed to demonstrate strong currents under various storm intensities such as category-4 to -5, category-2 to -3, and <span class="hlt">tropical</span> storm to category-1 TCs in the northwestern <span class="hlt">Pacific</span>. Current speeds over 2.0 m s-1 are observed under major TCs with the strongest mean currents to the right of the storm track. This study provides the characterization of the near-surface velocity response to all recorded TCs, and agrees roughly with Geisler's theory (1970). Our observations also verify earlier modeling results of Price (1983).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23112174','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23112174"><span>Indian Ocean warming modulates <span class="hlt">Pacific</span> climate change.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Luo, Jing-Jia; Sasaki, Wataru; Masumoto, Yukio</p> <p>2012-11-13</p> <p>It has been widely believed that the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> trade winds weakened in the last century and would further decrease under a warmer climate in the 21st century. Recent high-quality observations, however, suggest that the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> winds have actually strengthened in the past two decades. Precise causes of the recent <span class="hlt">Pacific</span> climate shift are uncertain. Here we explore how the enhanced <span class="hlt">tropical</span> Indian Ocean warming in recent decades favors stronger trade winds in the western <span class="hlt">Pacific</span> via the atmosphere and hence is likely to have contributed to the La Niña-like state (with enhanced east-west Walker circulation) through the <span class="hlt">Pacific</span> ocean-atmosphere interactions. Further analysis, based on 163 climate model simulations with centennial historical and projected external radiative forcing, suggests that the Indian Ocean warming relative to the <span class="hlt">Pacific</span>'s could play an important role in modulating the <span class="hlt">Pacific</span> climate changes in the 20th and 21st centuries.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.prh.noaa.gov/cphc/pages/hurrsafety.php','SCIGOVWS'); return false;" href="http://www.prh.noaa.gov/cphc/pages/hurrsafety.php"><span>Hurricane Safety and Information - <span class="hlt">Central</span> <span class="hlt">Pacific</span> Hurricane Center -</span></a></p> <p><a target="_blank" href="http://www.science.gov/aboutsearch.html">Science.gov Websites</a></p> <p></p> <p></p> <p>NOAA NWS United States Department of Commerce <span class="hlt">Central</span> <span class="hlt">Pacific</span> <em>Hurricane</em> Center National Oceanic and Distance Calculator Blank Tracking Maps â¾ Educational Resources Be Prepared! NWS <em>Hurricane</em> Prep Week Search For Go NWS All NOAA â¾ <em>Hurricane</em> Safety <em>Hurricane</em> Awareness Week Information from CPHC Red Cross</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUOSCT31A..08K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUOSCT31A..08K"><span>Distribution of dissolved zinc in the western and <span class="hlt">central</span> subarctic North <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kim, T.; Obata, H.; Gamo, T.</p> <p>2016-02-01</p> <p>Zinc (Zn) is an essential micronutrient for bacteria and phytoplankton in the ocean as it plays an important role in numerous enzyme systems involved in various metabolic processes. However, large-scale distributions of total dissolved Zn in the subarctic North <span class="hlt">Pacific</span> have not been investigated yet. In this study, we investigated the distributions of total dissolved Zn to understand biogeochemical cycling of Zn in the western and <span class="hlt">central</span> subarctic North <span class="hlt">Pacific</span> as a Japanese GEOTRACES project. Seawater samples were collected during the R/V Hakuho-maru KH-12-4 GEOTRACES GP 02 cruise (from August to October 2012), by using acid-cleaned Teflon-coated X-type Niskin samplers. Total dissolved Zn in seawater was determined using cathodic stripping voltammetry (CSV) after UV-digestion. In this study, total dissolved Zn concentrations in the western and <span class="hlt">central</span> subarctic North <span class="hlt">Pacific</span> commonly showed Zn increase from surface to approximately 400-500 m, just above the oxygen minimum layer. However, in the western subarctic North <span class="hlt">Pacific</span>, relatively higher Zn concentrations have also been observed at intermediate depths (800-1200 m), in comparison with those observed in deep waters. The relationship between Zn and Si in the western subarctic North <span class="hlt">Pacific</span> showed that Zn is slightly enriched at intermediate depths. These results may indicate that there are additional sources of Zn to intermediate water of the western subarctic North <span class="hlt">Pacific</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70155525','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70155525"><span>Modeled changes in extreme wave climates of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> over the 21st century: Implications for U.S. and U.S.-Affiliated atoll islands</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Shope, J.B.; Storlazzi, Curt; Erikson, Li H.; Hegermiller, C.A.</p> <p>2015-01-01</p> <p>Wave heights, periods, and directions were forecast for 2081–2100 using output from four coupled atmosphere–ocean global climate models for representative concentration pathway scenarios RCP4.5 and RCP8.5. Global climate model wind fields were used to drive the global WAVEWATCH-III wave model to generate hourly time-series of bulk wave parameters for 25 islands in the mid to western <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. December–February 95th percentile extreme significant wave heights under both climate scenarios decreased by 2100 compared to 1976–2010 historical values. Trends under both scenarios were similar, with the higher-emission RCP8.5 scenario displaying a greater decrease in extreme significant wave heights than where emissions are reduced in the RCP4.5 scenario. <span class="hlt">Central</span> equatorial <span class="hlt">Pacific</span> Islands displayed the greatest departure from historical values; significant wave heights decreased there by as much as 0.32 m during December–February and associated wave directions rotated approximately 30° clockwise during June–August compared to hindcast data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA137362','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA137362"><span>An Evaluation of 700 mb Aircraft Reconnaissance Data for Selected Northwest <span class="hlt">Pacific</span> <span class="hlt">Tropical</span> Cyclones.</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1983-09-01</p> <p>ccesearch flights inte both Atlantic and ncr-.hwust <span class="hlt">Pacific</span> <span class="hlt">tropical</span> cyclones. Infcrmation providal by these studies expanded and, in some cases, altered...This assumption iaplies t at the curl of the tangential frictional drag is equal to zero. This further implies that the partial derivative of the sur...20) at 30 NM1, prior to the period of most rapidl deepening, Is reflecti at 60 NNl, and possibly at 90 NMl. In the case of super typhoon. rip (Fig</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002SPIE.4480..307K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002SPIE.4480..307K"><span>Determination of the spatial variability of temperature and moisture near a <span class="hlt">tropical</span> <span class="hlt">Pacific</span> island with MTI satellite images</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kurzeja, Robert J.; O'Steen, Byron L.; Pendergast, Malcolm M.</p> <p>2002-01-01</p> <p>The <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Island of Nauru is a US DOE ARM observation site that monitors <span class="hlt">tropical</span> climate and atmospheric radiation. This observation site is ideal for validating MTI images because of the extensive deployment of continuously operating instruments. MTI images are also useful in assessing the effect of the island on the ocean climate and on the ARM data. An MTI image has been used to determine the spatial distribution of water vapor and sea-surface temperature near the island. The results are compared with a three-dimensional numerical model simulation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/1134073','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/1134073"><span>Final Report for UW-Madison Portion of DE-SC0005301, "Collaborative Project: <span class="hlt">Pacific</span> Decadal Variability and <span class="hlt">Central</span> <span class="hlt">Pacific</span> Warming El Niño in a Changing Climate"</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Vimont, Daniel</p> <p></p> <p>This project funded two efforts at understanding the interactions between <span class="hlt">Central</span> <span class="hlt">Pacific</span> ENSO events, the mid-latitude atmosphere, and decadal variability in the <span class="hlt">Pacific</span>. The first was an investigation of conditions that lead to <span class="hlt">Central</span> <span class="hlt">Pacific</span> (CP) and East <span class="hlt">Pacific</span> (EP) ENSO events through the use of linear inverse modeling with defined norms. The second effort was a modeling study that combined output from the National Center for Atmospheric Research (NCAR) Community Atmospheric Model (CAM4) with the Battisti (1988) intermediate coupled model. The intent of the second activity was to investigate the relationship between the atmospheric North <span class="hlt">Pacific</span> Oscillation (NPO), themore » <span class="hlt">Pacific</span> Meridional Mode (PMM), and ENSO. These two activities are described herein.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1997JAtS...54..725C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1997JAtS...54..725C"><span>Asymmetric Impact of <span class="hlt">Tropical</span> SST Anomalies on Atmospheric Internal Variability over the North <span class="hlt">Pacific</span>.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Wilbur Y.; van den Dool, Huug M.</p> <p>1997-03-01</p> <p>A substantial asymmetric impact of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> SST anomalies on the internal variability of the extratropical atmosphere is found. A variety of diagnoses is performed to help reveal the dynamical processes leading to the large impact. Thirty-five years of geopotential heights and 29 years of wind fields analyzed operationally at the National Centers for Environmental Prediction (NCEP), formerly the National Meteorological Center, and three sets of 10-yr-long perpetual January integrations run with a low-resolution NCEP global spectral model are investigated in detail for the impact of the SST anomalies on the blocking flows over the North <span class="hlt">Pacific</span>. The impact on large-scale deep trough flows is also examined.Both the blocking and deep trough flows develop twice as much over the North <span class="hlt">Pacific</span> during La Niña as during El Niño winters. Consequently, the internal dynamics associated low-frequency variability (LFV), with timescales between 7 and 61 days examined in this study, display distinct characteristics: much larger magnitude for the La Niña than the El Niño winters over the eastern North <span class="hlt">Pacific</span>, where the LFV is highest in general.The diagnosis of the localized Eliassen-Palm fluxes and their divergence reveals that the high-frequency transient eddies (1-7 days) at high latitudes are effective in forming and maintaining the large-scale blocking flows, while the midlatitude transients are less effective. The mean deformation field over the North <span class="hlt">Pacific</span> is much more diffluent for the La Niña than the El Niño winters, resulting in more blocking flows being developed and maintained during La Niña by the high-frequency transients over the <span class="hlt">central</span> North <span class="hlt">Pacific</span>.In addition to the above dynamical process operating on the high-frequency end of the spectrum, the local barotropic energy conversion between the LFV components and the time-mean flows is also operating and playing a crucial role. The kinetic energy conversion represented by the scalar product</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JAMES..10..961H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JAMES..10..961H"><span>The Role of Convective Gustiness in Reducing Seasonal Precipitation Biases in the <span class="hlt">Tropical</span> West <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Harrop, Bryce E.; Ma, Po-Lun; Rasch, Philip J.; Neale, Richard B.; Hannay, Cecile</p> <p>2018-04-01</p> <p>Precipitation is an important climate quantity that is critically relevant to society. In spite of intense efforts, significant precipitation biases remain in most climate models. One pervasive and persistent bias found in many general circulation models occurs in the <span class="hlt">Tropical</span> West <span class="hlt">Pacific</span> where northern hemisphere summer-time precipitation is often underestimated compared to observations. Using the DOE-E3SM model, the inclusion of a missing process, convective gustiness, is shown to reduce those biases through a net increase in surface evaporation. Gustiness in surface wind fields is assumed to arise empirically in proportion to the intensity of convective precipitation. The increased evaporation can be treated as an increase in the moist static energy forcing into the atmosphere. A Normalized Gross Moist Stability (NGMS) framework (which characterizes the relationship between convective forcing and convective response) is used to explore the processes responsible for the precipitation bias, and the impact of the gustiness parameterization in reducing that bias. Because the NGMS of the <span class="hlt">Tropical</span> West <span class="hlt">Pacific</span> is less than unity in the E3SMv1 model, the increase in energy forcing amplifies the increase in precipitation to exceed that of the evaporative flux. Convective gustiness favors increased precipitation in regions where the resolved surface winds are weak and convection is present.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27682252','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27682252"><span>Expansion and Contraction of the Indo-<span class="hlt">Pacific</span> <span class="hlt">Tropical</span> Rain Belt over the Last Three Millennia.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Denniston, Rhawn F; Ummenhofer, Caroline C; Wanamaker, Alan D; Lachniet, Matthew S; Villarini, Gabriele; Asmerom, Yemane; Polyak, Victor J; Passaro, Kristian J; Cugley, John; Woods, David; Humphreys, William F</p> <p>2016-09-29</p> <p>The seasonal north-south migration of the intertropical convergence zone (ITCZ) defines the <span class="hlt">tropical</span> rain belt (TRB), a region of enormous terrestrial and marine biodiversity and home to 40% of people on Earth. The TRB is dynamic and has been shown to shift south as a coherent system during periods of Northern Hemisphere cooling. However, recent studies of Indo-<span class="hlt">Pacific</span> hydroclimate suggest that during the Little Ice Age (LIA; AD 1400-1850), the TRB in this region contracted rather than being displaced uniformly southward. This behaviour is not well understood, particularly during climatic fluctuations less pronounced than those of the LIA, the largest centennial-scale cool period of the last millennium. Here we show that the Indo-<span class="hlt">Pacific</span> TRB expanded and contracted numerous times over multi-decadal to centennial scales during the last 3,000 yr. By integrating precisely-dated stalagmite records of <span class="hlt">tropical</span> hydroclimate from southern China with a newly enhanced stalagmite time series from northern Australia, our study reveals a previously unidentified coherence between the austral and boreal summer monsoon. State-of-the-art climate model simulations of the last millennium suggest these are linked to changes in the structure of the regional manifestation of the atmosphere's meridional circulation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5041111','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5041111"><span>Expansion and Contraction of the Indo-<span class="hlt">Pacific</span> <span class="hlt">Tropical</span> Rain Belt over the Last Three Millennia</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Denniston, Rhawn F.; Ummenhofer, Caroline C.; Wanamaker, Alan D.; Lachniet, Matthew S.; Villarini, Gabriele; Asmerom, Yemane; Polyak, Victor J.; Passaro, Kristian J.; Cugley, John; Woods, David; Humphreys, William F.</p> <p>2016-01-01</p> <p>The seasonal north-south migration of the intertropical convergence zone (ITCZ) defines the <span class="hlt">tropical</span> rain belt (TRB), a region of enormous terrestrial and marine biodiversity and home to 40% of people on Earth. The TRB is dynamic and has been shown to shift south as a coherent system during periods of Northern Hemisphere cooling. However, recent studies of Indo-<span class="hlt">Pacific</span> hydroclimate suggest that during the Little Ice Age (LIA; AD 1400–1850), the TRB in this region contracted rather than being displaced uniformly southward. This behaviour is not well understood, particularly during climatic fluctuations less pronounced than those of the LIA, the largest centennial-scale cool period of the last millennium. Here we show that the Indo-<span class="hlt">Pacific</span> TRB expanded and contracted numerous times over multi-decadal to centennial scales during the last 3,000 yr. By integrating precisely-dated stalagmite records of <span class="hlt">tropical</span> hydroclimate from southern China with a newly enhanced stalagmite time series from northern Australia, our study reveals a previously unidentified coherence between the austral and boreal summer monsoon. State-of-the-art climate model simulations of the last millennium suggest these are linked to changes in the structure of the regional manifestation of the atmosphere’s meridional circulation. PMID:27682252</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatSR...634485D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatSR...634485D"><span>Expansion and Contraction of the Indo-<span class="hlt">Pacific</span> <span class="hlt">Tropical</span> Rain Belt over the Last Three Millennia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Denniston, Rhawn F.; Ummenhofer, Caroline C.; Wanamaker, Alan D.; Lachniet, Matthew S.; Villarini, Gabriele; Asmerom, Yemane; Polyak, Victor J.; Passaro, Kristian J.; Cugley, John; Woods, David; Humphreys, William F.</p> <p>2016-09-01</p> <p>The seasonal north-south migration of the intertropical convergence zone (ITCZ) defines the <span class="hlt">tropical</span> rain belt (TRB), a region of enormous terrestrial and marine biodiversity and home to 40% of people on Earth. The TRB is dynamic and has been shown to shift south as a coherent system during periods of Northern Hemisphere cooling. However, recent studies of Indo-<span class="hlt">Pacific</span> hydroclimate suggest that during the Little Ice Age (LIA; AD 1400-1850), the TRB in this region contracted rather than being displaced uniformly southward. This behaviour is not well understood, particularly during climatic fluctuations less pronounced than those of the LIA, the largest centennial-scale cool period of the last millennium. Here we show that the Indo-<span class="hlt">Pacific</span> TRB expanded and contracted numerous times over multi-decadal to centennial scales during the last 3,000 yr. By integrating precisely-dated stalagmite records of <span class="hlt">tropical</span> hydroclimate from southern China with a newly enhanced stalagmite time series from northern Australia, our study reveals a previously unidentified coherence between the austral and boreal summer monsoon. State-of-the-art climate model simulations of the last millennium suggest these are linked to changes in the structure of the regional manifestation of the atmosphere’s meridional circulation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ClDy...50.4707C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ClDy...50.4707C"><span>Indo-<span class="hlt">Pacific</span> climate during the decaying phase of the 2015/16 El Niño: role of southeast <span class="hlt">tropical</span> Indian Ocean warming</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Zesheng; Du, Yan; Wen, Zhiping; Wu, Renguang; Wang, Chunzai</p> <p>2018-06-01</p> <p>This study investigates the influence of southeast <span class="hlt">tropical</span> Indian Ocean (SETIO) sea surface temperature (SST) warming on Indo-<span class="hlt">Pacific</span> climate during the decaying phase of the 2015/16 El Niño by using observations and model experiments. The results show that the SETIO SST warming in spring 2016 enhanced local convection and forced a "C-shape" wind anomaly pattern in the lower troposphere. The "C-shape" wind anomaly pattern over the eastern <span class="hlt">tropical</span> Indian Ocean consists of anomalous westerly flow south of the equator and anomalous easterly flow north of the equator. The anomalous easterly flow then extended eastward into the western North <span class="hlt">Pacific</span> (WNP) and facilitates the development or the maintenance of an anomalous anticyclone over the South China Sea (SCS). Correspondingly, the eastern part of the Bay of Bengal, the SCS and the WNP suffered less rainfall. Such precipitation features and the associated "C-shape" wind anomaly pattern shifted northward about five latitudes in summer 2016. Additionally, the SETIO warming can induce local meridional circulation anomalies, which directly affect Indo-<span class="hlt">Pacific</span> climate. Numerical model experiments further confirm that the SETIO SST warming plays an important role in modulating Indo-<span class="hlt">Pacific</span> climate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29666367','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29666367"><span>Westward migration of <span class="hlt">tropical</span> cyclone rapid-intensification over the Northwestern <span class="hlt">Pacific</span> during short duration El Niño.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Guo, Yi-Peng; Tan, Zhe-Min</p> <p>2018-04-17</p> <p>The El Niño-Southern Oscillation (ENSO) can significantly affect the rapid intensification of <span class="hlt">tropical</span> cyclones over the western North <span class="hlt">Pacific</span> (WNP). However, ENSO events have various durations, which can lead to different atmospheric and oceanic conditions. Here we show that during short duration El Niño events, the WNP <span class="hlt">tropical</span> cyclone rapid-intensification mean occurrence position migrates westward by ~8.0° longitude, which is caused by reduced vertical wind shear, increased mid-tropospheric humidity, and enhanced <span class="hlt">tropical</span> cyclone heat potential over the westernmost WNP. The changes in these factors are caused by westward advected upper ocean heat during the decaying phase of a short duration El Niño. As super El Niño events tend to have short durations and their frequency is projected to increase under global warming, our findings have important implications for future projections of WNP <span class="hlt">tropical</span> cyclone activity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001WRR....37.2143S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001WRR....37.2143S"><span><span class="hlt">Tropical</span> storms and the flood hydrology of the <span class="hlt">central</span> Appalachians</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sturdevant-Rees, Paula; Smith, James A.; Morrison, Julia; Baeck, Mary Lynn</p> <p>2001-08-01</p> <p>Flooding from Hurricane Fran is examined as a prototype for <span class="hlt">central</span> Appalachian flood events that dominate the upper tail of flood peak distributions at basin scales between 100 and 10,000 km2. Hurricane Fran, which resulted in 34 deaths and more than $3.2 billion in damages, made land fall on the North Carolina coast at 0000 UTC, September 6, 1996. By 1200 UTC on September 6, Fran had weakened to a <span class="hlt">tropical</span> storm, and the center of circulation was located at the North Carolina-Virginia border. Rain bands surrounding the <span class="hlt">tropical</span> depression produced extreme rainfall and flooding in Virginia and West Virginia, with the most intense rainfall concentrated near ridge tops in the Blue Ridge and Valley and Ridge physiographic provinces. The most severe flooding occurred in the Shenandoah River watershed of Virginia, where peak discharges exceeded the 100-year magnitude at 11 of 19 U.S. Geological Survey stream-gaging stations. The availability of high-resolution discharge and rainfall data sets provides the opportunity to study the hydrologic and hydrometeorological mechanisms associated with extreme floods produced by <span class="hlt">tropical</span> storms. Analyses indicate that orographie enhancement of <span class="hlt">tropical</span> storm precipitation plays a <span class="hlt">central</span> role in the hydrology of extreme floods in the <span class="hlt">central</span> Appalachian region. The relationships between drainage network structure and storm motion also play a major role in Appalachian flood hydrology. Runoff processes for Hurricane Fran reflected a mixture of saturation excess and infiltration excess mechanisms. Antecedent soil moisture played a significant role in the hydrology of extreme flooding from Hurricane Fran. Land use, in particular, the presence of forest cover, was of secondary importance to the terrain-based distribution of precipitation in determining extreme flood response.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29769741','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29769741"><span><span class="hlt">Tropical</span> Meridional Overturning Circulation Observed by Subsurface Moorings in the Western <span class="hlt">Pacific</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Song, Lina; Li, Yuanlong; Wang, Jianing; Wang, Fan; Hu, Shijian; Liu, Chuanyu; Diao, Xinyuan; Guan, Cong</p> <p>2018-05-16</p> <p>Meridional ocean current in the northwestern <span class="hlt">Pacific</span> was documented by seven subsurface moorings deployed at 142°E during August 2014-October 2015. A sandwich structure of the <span class="hlt">tropical</span> meridional overturning circulation (TMOC) was revealed between 0-6°N that consists of a surface northward flow (0-80 m), a thermocline southward flow (80-260 m; 22.6-26.5 σ θ ), and a subthermocline northward flow (260-500 m; 26.5-26.9 σ θ ). Based on mooring data, along with satellite and reanalysis data, prominent seasonal-to-interannual variations were observed in all three layers, and the equatorial zonal winds were found to be a dominant cause of the variations. The TMOC is generally stronger in boreal winter and weaker in summer. During 2014-2015, the TMOC was greatly weakened by westerly wind anomalies associated with the El Niño condition. Further analysis suggests that the TMOC can affect equatorial surface temperature in the western <span class="hlt">Pacific</span> through anomalous upwelling/downwelling and likely plays a vital role in the El Niño-Southern Oscillation (ENSO).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AtmEn.122..148K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AtmEn.122..148K"><span>Enhancement in the upper tropospheric humidity associated with aerosol loading over <span class="hlt">tropical</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kottayil, Ajil; Satheesan, K.</p> <p>2015-12-01</p> <p>Many modeling studies have indicated that aerosol interactions with clouds increase the upper tropospheric humidity (UTH), but observational evidences are sparse. Using satellite datasets of upper tropospheric humidity and aerosols, this study shows that aerosols increase the upper tropospheric humidity over the <span class="hlt">tropical</span> North West <span class="hlt">Pacific</span> (NWP) and North East <span class="hlt">Pacific</span> (NEP). The observations show an increase in the UTH by 2.8%RH over NEP for an increment of 0.12 in aerosol optical depth (AOD) and 2%RH increase in UTH over NWP for an increment of 0.19 in AOD. The study also quantifies the change in longwave cloud radiative forcing (LWCRF) as a consequence of the increase in UTH due to aerosols. The LWCRF increases by 3.38 W m-2 over NEP and by 4.46 W m-2 over NWP. The result that aerosols increase the upper tropospheric humidity is significant since the latter plays a crucial role in regulating the Earth's radiation budget and water vapor feedback.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.A53F..01C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.A53F..01C"><span>Relationships Among Atmospheric Rivers, <span class="hlt">Tropical</span> Moisture Exports, and Warm Conveyor Belts over the Northeast <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cordeira, J. M.</p> <p>2015-12-01</p> <p>Extreme precipitation and attendant floods annually result in 80 fatalities and $5 Billion in damages across the U.S. and account for 50% of annual average U.S. natural disaster losses. The mechanisms that produce extreme precipitation are well known and are relatively well simulated by modern numerical weather prediction models in conjunction with synoptic-scale and mesoscale lift, instability, moisture, and boundaries. The focus of this presentation is on moisture in the form of synoptic-scale water vapor transport and its role in extreme precipitation along the U.S. West Coast. Many different terms have been used to describe synoptic-scale water vapor transport over the Northeast <span class="hlt">Pacific</span>, including: moisture conveyor belts, warm conveyor belts, <span class="hlt">tropical</span> moisture exports, <span class="hlt">tropical</span> plumes, moisture plumes, pineapple express events, and atmospheric rivers. Each term respectively attempts to quantify or represent the propagation or instantaneous movement of water vapor from the Lagrangian and Eulerian frameworks in which they exist. These differences in frameworks often makes comparing and contrasting, for example, warm conveyor belts and atmospheric rivers difficult and may lead to misguided interpretations of long-range trans-oceanic water vapor transport. The purpose of this presentation is to discuss the dynamics of water vapor transport over the Northeast <span class="hlt">Pacific</span> from the Eulerian and Lagrangian frameworks and illustrate to what degree the two- and three-dimensional structures of these rivers, exports, and belts overlap. Illustration of overlap between these processes will be shown via case study analysis of synoptic-scale water vapor transport over the Northeast <span class="hlt">Pacific</span> that led to heavy precipitation along the U.S. West Coast during February 2014 and February 2015.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002JGRD..107.8402K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002JGRD..107.8402K"><span>Effects of biomass burning, lightning, and convection on O3, CO, and NOy over the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> and Australia in August-October 1998 and 1999</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kondo, Y.; Koike, M.; Kita, K.; Ikeda, H.; Takegawa, N.; Kawakami, S.; Blake, D.; Liu, S. C.; Ko, M.; Miyazaki, Y.; Irie, H.; Higashi, Y.; Liley, B.; Nishi, N.; Zhao, Y.; Ogawa, T.</p> <p>2002-02-01</p> <p>In situ aircraft measurements of O3, CO, total reactive nitrogen (NOy), NO, and non-methane hydrocarbons (NMHCs) were made over the western <span class="hlt">Pacific</span> Ocean and Australia during the Biomass Burning and Lightning Experiment (BIBLE) A and B conducted in August-October 1998 and 1999. Generally, similar features were seen in the BIBLE A and B data in the latitudinal variations of these species in the troposphere from 35°N to 28°S at longitudes of 120°-150°E. The focus of this paper is to describe the characteristics of air masses sampled at 15°N-10°S (<span class="hlt">tropical</span> <span class="hlt">Pacific</span>) and 10°S-28°S (over Australia). With the exception of occasional enhancements in reactive nitrogen seen over New Guinea associated with lightning activities, the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> region is distinguished from the rest of the region by smaller concentrations of these trace species. This can be explained in terms of the absence of surface sources over the ocean, lack of stratospheric intrusion, and the preclusion of midlatitude air and air from the west due to active convection throughout the troposphere. The median O3, CO, NOy, and NO mixing ratios in <span class="hlt">tropical</span> air above 4 km were about 15-20 parts per billion by volume (ppbv), 60-75 ppbv, 20-100 parts per trillion by volume (pptv), and 5-40 pptv, respectively. Data obtained from PEM-West A and B conducted in 1991 and 1994 showed similar latitudinal features, although the PEM-West A values were somewhat elevated due to dominating westerly winds in the lower troposphere associated with El Niño. Over Australia, the levels of O3, CO, NOy, NO, and NMHCs were elevated throughout the troposphere over those observed in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> both in 1998 and 1999. The effect from biomass burning that occurred in northern Australia was limited to within the boundary layer because of strong subsidence in the period. Analyses based on 14-day back trajectories identified free tropospheric air over Australia that originated from Indonesia, the Indian Ocean, Africa</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003JGRD..108.8402K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003JGRD..108.8402K"><span>Effects of biomass burning, lightning, and convection on O3, CO, and NOy over the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> and Australia in August-October 1998 and 1999</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kondo, Y.; Koike, M.; Kita, K.; Ikeda, H.; Takegawa, N.; Kawakami, S.; Blake, D.; Liu, S. C.; Ko, M.; Miyazaki, Y.; Irie, H.; Higashi, Y.; Liley, B.; Nishi, N.; Zhao, Y.; Ogawa, T.</p> <p>2003-02-01</p> <p>In situ aircraft measurements of O3, CO, total reactive nitrogen (NOy), NO, and non-methane hydrocarbons (NMHCs) were made over the western <span class="hlt">Pacific</span> Ocean and Australia during the Biomass Burning and Lightning Experiment (BIBLE) A and B conducted in August-October 1998 and 1999. Generally, similar features were seen in the BIBLE A and B data in the latitudinal variations of these species in the troposphere from 35°N to 28°S at longitudes of 120°-150°E. The focus of this paper is to describe the characteristics of air masses sampled at 15°N-10°S (<span class="hlt">tropical</span> <span class="hlt">Pacific</span>) and 10°S-28°S (over Australia). With the exception of occasional enhancements in reactive nitrogen seen over New Guinea associated with lightning activities, the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> region is distinguished from the rest of the region by smaller concentrations of these trace species. This can be explained in terms of the absence of surface sources over the ocean, lack of stratospheric intrusion, and the preclusion of midlatitude air and air from the west due to active convection throughout the troposphere. The median O3, CO, NOy, and NO mixing ratios in <span class="hlt">tropical</span> air above 4 km were about 15-20 parts per billion by volume (ppbv), 60-75 ppbv, 20-100 parts per trillion by volume (pptv), and 5-40 pptv, respectively. Data obtained from PEM-West A and B conducted in 1991 and 1994 showed similar latitudinal features, although the PEM-West A values were somewhat elevated due to dominating westerly winds in the lower troposphere associated with El Niño. Over Australia, the levels of O3, CO, NOy, NO, and NMHCs were elevated throughout the troposphere over those observed in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> both in 1998 and 1999. The effect from biomass burning that occurred in northern Australia was limited to within the boundary layer because of strong subsidence in the period. Analyses based on 14-day back trajectories identified free tropospheric air over Australia that originated from Indonesia, the Indian Ocean, Africa</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20010125151&hterms=ozone+layer&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dozone%2Blayer','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20010125151&hterms=ozone+layer&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dozone%2Blayer"><span>Low Ozone in the Marine Boundary Layer of the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Singh, Hanwant B.; Gregory, G. L.; Andesrson, B.; Browell, E.; Sachse, G. W.; Davis, D. D.; Crawford, J.; Bradshaw, J. D.; Talbot, R.; Blake, D. R.; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20010125151'); toggleEditAbsImage('author_20010125151_show'); toggleEditAbsImage('author_20010125151_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20010125151_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20010125151_hide"></p> <p>1994-01-01</p> <p>Aircraft measurements of ozone, its key precursors, and a variety of chemical tracers were made in the troposphere of the western and <span class="hlt">central</span> <span class="hlt">Pacific</span> in October 1991. These data are presented and analyzed to examine the occurrence of low ozone concentrations in the remote marine boundary layer of the <span class="hlt">tropical</span> and equatorial <span class="hlt">Pacific</span> Ocean. The data from these flights out of Guam, covering an area extending from the equator to 20 N and from south of the Philippines to Hawaii, show average O3 concentrations as low as 8-9 ppb (ppb=10(exp-9)v/v) at altitudes of 0.3-0.5 km in the boundary layer. Individual measurements as low as 2-5 ppb were recorded. Low O3 concentrations do not always persist in space and time. High O3, generally associated with the transport of upper tropospheric air, was also encountered in the boundary layer. In practically all cases, O3 increased to values as large as 25-30 ppb within 2 km above the boundary layer top. Steady state model computations are used to suggest that these low O3 concentrations are a result of net photochemical O3 destruction in a low NO environment, sea-surface deposition, and extremely low net entrainment rates (1-2 mm per second) from the free troposphere. Day/night measurements of ethane, propane, gaseous and aerosol Cl suggest that daytime (morning) Cl atom concentrations in the vicinity of 10(exp 5) molecules per cubic centimeter may be present in the marine boundary layer. This Cl atom abundance can be rationalized only if sea salt aerosols can release free chlorine (Cl2) to the gas phase in the presence of sun light (and possibly O3). These Cl atom concentrations, however, are still insufficient and Cl (or Br) chemistry is not likely to be an important cause of the observed low O3.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017GeoRL..44.7945D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017GeoRL..44.7945D"><span>The relative contributions of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> sea surface temperatures and atmospheric internal variability to the recent global warming hiatus</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Deser, Clara; Guo, Ruixia; Lehner, Flavio</p> <p>2017-08-01</p> <p>The recent slowdown in global mean surface temperature (GMST) warming during boreal winter is examined from a regional perspective using 10-member initial-condition ensembles with two global coupled climate models in which observed <span class="hlt">tropical</span> <span class="hlt">Pacific</span> sea surface temperature anomalies (TPAC SSTAs) and radiative forcings are specified. Both models show considerable diversity in their surface air temperature (SAT) trend patterns across the members, attesting to the importance of internal variability beyond the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> that is superimposed upon the response to TPAC SSTA and radiative forcing. Only one model shows a close relationship between the realism of its simulated GMST trends and SAT trend patterns. In this model, Eurasian cooling plays a dominant role in determining the GMST trend amplitude, just as in nature. In the most realistic member, intrinsic atmospheric dynamics and teleconnections forced by TPAC SSTA cause cooling over Eurasia (and North America), and contribute equally to its GMST trend.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMPP41E..06M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMPP41E..06M"><span>The <span class="hlt">Pacific</span> SST response to volcanic eruptions over the past millennium based on the CESM-LME</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Man, W.; Zuo, M.</p> <p>2017-12-01</p> <p>The impact of the northern hemispheric, <span class="hlt">tropical</span> and southern hemispheric volcanic eruptions on the <span class="hlt">Pacific</span> sea surface temperature (SST) and its mechanism are investigated using the Community Earth System Model Last Millennium Ensemble. Analysis of the simulations indicates that the <span class="hlt">Pacific</span> SST features a significant El Niño-like pattern a few months after the northern hemispheric and <span class="hlt">tropical</span> eruptions, and with a weaker such tendency after the southern hemispheric eruptions. Furthermore, the Niño3 index peaks lagging one and a half years after the northern hemispheric and <span class="hlt">tropical</span> eruptions. Two years after all three types of volcanic eruptions, a La Niña-like pattern over the equatorial <span class="hlt">Pacific</span> is observed, which seems to form an El Niño-Southern Oscillation (ENSO) cycle. In addition, the westerly anomalies at 850 hPa over the western-to-<span class="hlt">central</span> <span class="hlt">Pacific</span> appear ahead of the warm SST; hence, the El Niño-like warming over the eastern <span class="hlt">Pacific</span> can be attributed to the weakening of the trade winds. We further examined the causes of westerly anomalies and find that a shift of the intertropical convergence zone (ITCZ) can explain the El Niño-like response to the northern hemispheric eruptions, which is not applicable for <span class="hlt">tropical</span> or southern hemispheric eruptions. Instead, the reduction in the zonal equatorial SST gradient through the ocean dynamical thermostat mechanism, combined with the land-sea thermal contrast between the Maritime Continent (MC) and the surrounding ocean and the divergent wind induced by the decreased precipitation over the MC, can trigger the westerly anomalies over the equatorial <span class="hlt">Pacific</span>, which is applicable for all three types of eruptions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMPP33B1324H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMPP33B1324H"><span><span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Mean State and ENSO Variability across Marine Isotope Stage 3</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hertzberg, J. E.; Schmidt, M. W.; Marcantonio, F.; Bianchi, T. S.</p> <p>2017-12-01</p> <p>The El Niño/Southern Oscillation (ENSO) phenomenon is the largest natural interannual signal in the Earth's climate system and has widespread effects on global climate that impact millions of people worldwide. A series of recent research studies predict an increase in the frequency of extreme El Niño and La Niña events as Earth's climate continues to warm. In order for climate scientists to forecast how ENSO will evolve in response to global warming, it is necessary to have accurate, comprehensive records of how the system has naturally changed in the past, especially across past abrupt warming events. Nevertheless, there remains significant uncertainty about past changes in <span class="hlt">tropical</span> <span class="hlt">Pacific</span> climate and how ENSO variability relates to the millennial-scale warming events of the last ice age. This study aims to reconstruct changes in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> mean state and ENSO variability across Marine Isotope Stage 3 from a sediment core recovered from the Eastern Equatorial <span class="hlt">Pacific</span> cold tongue (MV1014-02-17JC, 0°10.8' S, 85°52.0' W, 2846 m water depth). In this region, thermocline temperatures are significantly correlated to ENSO variability - thus, we analyzed Mg/Ca ratios in the thermocline dwelling foraminifera Neogloboquadrina dutertrei as a proxy for thermocline temperatures in the past. Bulk ( 50 tests/sample) foraminifera Mg/Ca temperatures are used to reconstruct long-term variability in the mean state, while single shell ( 1 test/sample, 60 samples) Mg/Ca analyses are used to assess thermocline temperature variance. Based on our refined age model, we find that thermocline temperature increases of up to 3.5°C occur in-step with interstadial warming events recorded in Greenland ice cores. Cooler thermocline temperatures prevail during stadial intervals and Heinrich Events. This suggests that interstadials were more El-Niño like, while stadials and Heinrich Events were more La-Niña like. These temperature changes are compared to new records of dust flux</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhDT.......446K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhDT.......446K"><span>Global warming and <span class="hlt">tropical</span> cyclone climate in the western North <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kang, Nam-Young</p> <p></p> <p>Violent <span class="hlt">tropical</span> cyclones (TCs) continue to inflict serious impacts on national economies and welfare, but how they are responding to global warming has not been fully clarified. Here I construct an empirical framework that shows the observations supporting a strong link between rising global ocean warmth and increasing trade-off between TC intensity and frequency in the western North <span class="hlt">Pacific</span>. Thermodynamic structure of the <span class="hlt">tropical</span> western North <span class="hlt">Pacific</span> with high global ocean warmth is characterized by convectively more unstable lower troposphere with greater heat and moisture, but this instability is simultaneously accompanied by anomalous high pressure in the middle and upper troposphere over the same region. Increasing trade-off level between TC intensity and frequency in a warmer year proves that this environment further inhibits the TC occurrences over the region, but TCs that form tend to discharge stored energy to upper troposphere with stronger intensities. By increasing the intensity threshold at higher levels we confirmed that the TC climate connection with global ocean warmth occurs throughout the strongest portion of TCs, and the environmental connection of the TC climate is more conspicuous in the extreme portion of TCs. Intensities at the strongest 10~% of the western North <span class="hlt">Pacific</span> TCs are comparable to super typhoons on average, the increasing trade-off magnitude clearly suggests that super typhoons in a warmer year gets stronger. Conclusively, the negative collinear feature of the thermodynamics influences the portion of TCs at the highest intensities, and super typhoons are likely to become stronger at the expense of overall TC frequencies in a warmer world. The consequence of this finding is that record-breaking TC intensities occur at the expense of overall TC frequencies under global warming. TC activity is understood as a variation which is independent of global warming, and could be assumed to be an internal variability having no trend</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatCC...6..275L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatCC...6..275L"><span>Atlantic-induced pan-<span class="hlt">tropical</span> climate change over the past three decades</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Xichen; Xie, Shang-Ping; Gille, Sarah T.; Yoo, Changhyun</p> <p>2016-03-01</p> <p>During the past three decades, <span class="hlt">tropical</span> sea surface temperature (SST) has shown dipole-like trends, with warming over the <span class="hlt">tropical</span> Atlantic and Indo-western <span class="hlt">Pacific</span> but cooling over the eastern <span class="hlt">Pacific</span>. Competing hypotheses relate this cooling, identified as a driver of the global warming hiatus, to the warming trends in either the Atlantic or Indian Ocean. However, the mechanisms, the relative importance and the interactions between these teleconnections remain unclear. Using a state-of-the-art climate model, we show that the Atlantic plays a key role in initiating the <span class="hlt">tropical</span>-wide teleconnection, and the Atlantic-induced anomalies contribute ~55-75% of the <span class="hlt">tropical</span> SST and circulation changes during the satellite era. The Atlantic warming drives easterly wind anomalies over the Indo-western <span class="hlt">Pacific</span> as Kelvin waves and westerly anomalies over the eastern <span class="hlt">Pacific</span> as Rossby waves. The wind changes induce an Indo-western <span class="hlt">Pacific</span> warming through the wind-evaporation-SST effect, and this warming intensifies the La Niña-type response in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> by enhancing the easterly trade winds and through the Bjerknes ocean dynamical processes. The teleconnection develops into a <span class="hlt">tropical</span>-wide SST dipole pattern. This mechanism, supported by observations and a hierarchy of climate models, reveals that the <span class="hlt">tropical</span> ocean basins are more tightly connected than previously thought.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ChJOL..34..567D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ChJOL..34..567D"><span>Difference in the influence of Indo-<span class="hlt">Pacific</span> Ocean heat content on South Asian Summer Monsoon intensity before and after 1976/1977</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dong, Yujie; Feng, Junqiao; Hu, Dunxin</p> <p>2016-05-01</p> <p>Monthly ocean temperature from ORAS4 datasets and atmospheric data from NCEP/NCAR Reanalysis I/II were used to analyze the relationship between the intensity of the South Asian summer monsoon (SASM) and upper ocean heat content (HC) in the <span class="hlt">tropical</span> Indo-<span class="hlt">Pacific</span> Ocean. The monsoon was differentiated into a Southwest Asian Summer Monsoon (SWASM) (2.5°-20°N, 35°-70°E) and Southeast Asian Summer Monsoon (SEASM) (2.5°-20°N, 70°-110°E). Results show that before the 1976/77 climate shift, the SWASM was strongly related to HC in the southern Indian Ocean and <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean. The southern Indian Ocean affected SWASM by altering the pressure gradient between southern Africa and the northern Indian Ocean and by enhancing the Somali cross-equatorial flow. The <span class="hlt">tropical</span> <span class="hlt">Pacific</span> impacted the SWASM through the remote forcing of ENSO. After the 1976/77 shift, there was a close relationship between equatorial <span class="hlt">central</span> <span class="hlt">Pacific</span> HC and the SEASM. However, before that shift, their relationship was weak.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMOS13A1795Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMOS13A1795Y"><span>Indo-<span class="hlt">Pacific</span> sea level variability during recent decades</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yamanaka, G.; Tsujino, H.; Nakano, H.; Urakawa, S. L.; Sakamoto, K.</p> <p>2016-12-01</p> <p>Decadal variability of sea level in the Indo-<span class="hlt">Pacific</span> region is investigated using a historical OGCM simulation. The OGCM driven by the atmospheric forcing removing long-term trends clearly exhibits decadal sea level variability in the <span class="hlt">Pacific</span> Ocean, which is associated with eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> thermal anomalies. During the period of 1977-1987, the sea level anomalies are positive in the eastern equatorial <span class="hlt">Pacific</span> and show deviations from a north-south symmetric distribution, with strongly negative anomalies in the western <span class="hlt">tropical</span> South <span class="hlt">Pacific</span>. During the period of 1996-2006, in contrast, the sea level anomalies are negative in the eastern equatorial <span class="hlt">Pacific</span> and show a nearly north-south symmetric pattern, with positive anomalies in both hemispheres. Concurrently, sea level anomalies in the south-eastern Indian Ocean vary with those in the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. These sea level variations are closely related to large-scale wind fields. Indo-<span class="hlt">Pacific</span> sea level distributions are basically determined by wind anomalies over the equatorial region as well as wind stress curl anomalies over the off-equatorial region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NHESS..16.1431M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NHESS..16.1431M"><span>An intercomparison of <span class="hlt">tropical</span> cyclone best-track products for the southwest <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Magee, Andrew D.; Verdon-Kidd, Danielle C.; Kiem, Anthony S.</p> <p>2016-06-01</p> <p>Recent efforts to understand <span class="hlt">tropical</span> cyclone (TC) activity in the southwest <span class="hlt">Pacific</span> (SWP) have led to the development of numerous TC databases. The methods used to compile each database vary and are based on data from different meteorological centres, standalone TC databases and archived synoptic charts. Therefore the aims of this study are to (i) provide a spatio-temporal comparison of three TC best-track (BT) databases and explore any differences between them (and any associated implications) and (ii) investigate whether there are any spatial, temporal or statistical differences between pre-satellite (1945-1969), post-satellite (1970-2011) and post-geostationary satellite (1982-2011) era TC data given the changing observational technologies with time. To achieve this, we compare three best-track TC databases for the SWP region (0-35° S, 135° E-120° W) from 1945 to 2011: the Joint Typhoon Warning Center (JTWC), the International Best Track Archive for Climate Stewardship (IBTrACS) and the Southwest <span class="hlt">Pacific</span> Enhanced Archive of <span class="hlt">Tropical</span> Cyclones (SPEArTC). The results of this study suggest that SPEArTC is the most complete repository of TCs for the SWP region. In particular, we show that the SPEArTC database includes a number of additional TCs, not included in either the JTWC or IBTrACS database. These SPEArTC events do occur under environmental conditions conducive to <span class="hlt">tropical</span> cyclogenesis (TC genesis), including anomalously negative 700 hPa vorticity (VORT), anomalously negative vertical shear of zonal winds (VSZW), anomalously negative 700 hPa geopotential height (GPH), cyclonic (absolute) 700 hPa winds and low values of absolute vertical wind shear (EVWS). Further, while changes in observational technologies from 1945 have undoubtedly improved our ability to detect and monitor TCs, we show that the number of TCs detected prior to the satellite era (1945-1969) are not statistically different to those in the post-satellite era (post-1970). Although data from</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.3932V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.3932V"><span>Paleoenvironments, Evolution, and Geomicrobiology in a <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Lake: The Lake Towuti Drilling Project (TOWUTI)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vogel, Hendrik; Russell, James M.; Bijaksana, Satria; Crowe, Sean; Fowle, David; Haffner, Douglas; King, John; Marwoto, Ristiyanti; Melles, Martin; von Rintelen, Thomas; Stevenson, Janelle; Watkinson, Ian; Wattrus, Nigel</p> <p>2014-05-01</p> <p>Lake Towuti (2.5°S, 121°E) is a, 560 km2, 200-m deep tectonic lake at the downstream end of the Malili lake system, a set of five, ancient (1-2 MYr) tectonic lakes in <span class="hlt">central</span> Sulawesi, Indonesia. Lake Towuti's location in <span class="hlt">central</span> Indonesia provides a unique opportunity to reconstruct long-term paleoclimate change in a crucially important yet understudied region- the Indo-<span class="hlt">Pacific</span> warm pool (IPWP), heart of the El Niño-Southern Oscillation. The Malili Lakes have extraordinarily high rates of floral and faunal endemism, and the lakes are surrounded by one of the most diverse <span class="hlt">tropical</span> forests on Earth. Drilling in Lake Towuti will identify the age and origin of the lake and the environmental and climatic context that shaped the evolution of this unique lacustrine and terrestrial ecosystem. The ultramafic (ophiolitic) rocks and lateritic soils surrounding Lake Towuti provide metal substrates that feed a diverse, exotic microbial community, analogous to the microbial ecosystems that operated in the Archean Oceans. Drill core will provide unique insight into long-term changes in this ecosystem, as well as microbial processes operating at depth in the sediment column. High-resolution seismic reflection data (CHIRP and airgun) combined with numerous long sediment piston cores collected from 2007-2013 demonstrate the enormous promise of Lake Towuti for an ICDP drilling campaign. Well-stratified sequences of up to 150 m thickness, uninterrupted by unconformities or erosional truncation, are present in multiple sub-basins within Towuti, providing ideal sites for long-term environmental, climatic, and limnological reconstructions. Multiproxy analyses of our piston cores document a continuous and detailed record of moisture balance variations in Lake Towuti during the past 60 kyr BP. In detail our datasets show that wet conditions and rainforest ecosystems in <span class="hlt">central</span> Indonesia persisted during Marine Isotope Stage 3 (MIS3) and the Holocene, and were interrupted by severe</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25119567','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25119567"><span>Hydroclimate variations in <span class="hlt">central</span> and monsoonal Asia over the past 700 years.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Fang, Keyan; Chen, Fahu; Sen, Asok K; Davi, Nicole; Huang, Wei; Li, Jinbao; Seppä, Heikki</p> <p>2014-01-01</p> <p>Hydroclimate variations since 1300 in <span class="hlt">central</span> and monsoonal Asia and their interplay on interannual and interdecadal timescales are investigated using the tree-ring based Palmer Drought Severity Index (PDSI) reconstructions. Both the interannual and interdecadal variations in both regions are closely to the <span class="hlt">Pacific</span> Decadal Oscillation (PDO). On interannual timescale, the most robust correlations are observed between PDO and hydroclimate in <span class="hlt">central</span> Asia. Interannual hydroclimate variations in <span class="hlt">central</span> Asia are more significant during the warm periods with high solar irradiance, which is likely due to the enhanced variability of the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean, the high-frequency component of PDO, during the warm periods. We observe that the periods with significant interdecadal hydroclimate changes in <span class="hlt">central</span> Asia often correspond to periods without significant interdecadal variability in monsoonal Asia, particularly before the 19th century. The PDO-hydroclimate relationships appear to be bridged by the atmospheric circulation between <span class="hlt">central</span> North <span class="hlt">Pacific</span> Ocean and Tibetan Plateau, a key area of PDO. While, in some periods the atmospheric circulation between <span class="hlt">central</span> North <span class="hlt">Pacific</span> Ocean and monsoonal Asia may lead to significant interdecadal hydroclimate variations in monsoonal Asia.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4131873','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4131873"><span>Hydroclimate Variations in <span class="hlt">Central</span> and Monsoonal Asia over the Past 700 Years</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Fang, Keyan; Chen, Fahu; Sen, Asok K.; Davi, Nicole; Huang, Wei; Li, Jinbao; Seppä, Heikki</p> <p>2014-01-01</p> <p>Hydroclimate variations since 1300 in <span class="hlt">central</span> and monsoonal Asia and their interplay on interannual and interdecadal timescales are investigated using the tree-ring based Palmer Drought Severity Index (PDSI) reconstructions. Both the interannual and interdecadal variations in both regions are closely to the <span class="hlt">Pacific</span> Decadal Oscillation (PDO). On interannual timescale, the most robust correlations are observed between PDO and hydroclimate in <span class="hlt">central</span> Asia. Interannual hydroclimate variations in <span class="hlt">central</span> Asia are more significant during the warm periods with high solar irradiance, which is likely due to the enhanced variability of the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean, the high-frequency component of PDO, during the warm periods. We observe that the periods with significant interdecadal hydroclimate changes in <span class="hlt">central</span> Asia often correspond to periods without significant interdecadal variability in monsoonal Asia, particularly before the 19th century. The PDO-hydroclimate relationships appear to be bridged by the atmospheric circulation between <span class="hlt">central</span> North <span class="hlt">Pacific</span> Ocean and Tibetan Plateau, a key area of PDO. While, in some periods the atmospheric circulation between <span class="hlt">central</span> North <span class="hlt">Pacific</span> Ocean and monsoonal Asia may lead to significant interdecadal hydroclimate variations in monsoonal Asia. PMID:25119567</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23019644','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23019644"><span>Out of the <span class="hlt">tropics</span>: the <span class="hlt">Pacific</span>, Great Basin lakes, and late Pleistocene water cycle in the western United States.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lyle, Mitchell; Heusser, Linda; Ravelo, Christina; Yamamoto, Masanobu; Barron, John; Diffenbaugh, Noah S; Herbert, Timothy; Andreasen, Dyke</p> <p>2012-09-28</p> <p>The water cycle in the western United States changed dramatically over glacial cycles. In the past 20,000 years, higher precipitation caused desert lakes to form which have since dried out. Higher glacial precipitation has been hypothesized to result from a southward shift of <span class="hlt">Pacific</span> winter storm tracks. We compared <span class="hlt">Pacific</span> Ocean data to lake levels from the interior west and found that Great Basin lake high stands are older than coastal wet periods at the same latitude. Westerly storms were not the source of high precipitation. Instead, air masses from the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> were transported northward, bringing more precipitation into the Great Basin when coastal California was still dry. The changing climate during the deglaciation altered precipitation source regions and strongly affected the regional water cycle.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70048039','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70048039"><span>Out of the <span class="hlt">tropics</span>: the <span class="hlt">Pacific</span>, Great Basin lakes, and late Pleistocene water cycle in the western United States</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Lyle, Mitchell; Heusser, Linda; Ravelo, Christina; Yamamoto, Masanobu; Barron, John; Diffenbaugh, Noah S.; Herbert, Timothy; Andreasen, Dyke</p> <p>2012-01-01</p> <p>The water cycle in the western U.S. changed dramatically over glacial cycles. In the last 20,000 years, higher precipitation caused desert lakes to form which have since dried out. Higher glacial precipitation is hypothesized to result from a southward shift of <span class="hlt">Pacific</span> winter storm tracks. We compared <span class="hlt">Pacific</span> Ocean data to lake levels from the interior west and found that Great Basin lake high stands are older than coastal wet periods at the same latitude. Westerly storms were not the source of high precipitation. Instead, air masses from the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> were transported northward, bringing more precipitation into the Great Basin when coastal California was still dry. The changing climate during the deglaciation altered precipitation source regions and strongly affected the regional water cycle.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.loc.gov/pictures/collection/hh/item/ut0700.photos.364225p/','SCIGOV-HHH'); return false;" href="https://www.loc.gov/pictures/collection/hh/item/ut0700.photos.364225p/"><span>Trestles #2 and #1 (center), long view from <span class="hlt">Central</span> <span class="hlt">Pacific</span> ...</span></a></p> <p><a target="_blank" href="http://www.loc.gov/pictures/collection/hh/">Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey</a></p> <p></p> <p></p> <p>Trestles #2 and #1 (center), long view from <span class="hlt">Central</span> <span class="hlt">Pacific</span> Railroad grade. Note Adams Ranch (right). View to north - Promontory Route Railroad Trestles, S.P. Trestle 779.91, One mile southwest of junction of State Highway 83 and Blue Creek, Corinne, Box Elder County, UT</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ClDy..tmp..919P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ClDy..tmp..919P"><span>What drove the <span class="hlt">Pacific</span> and North America climate anomalies in winter 2014/15?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Peng, Peitao; Kumar, Arun; Hu, Zeng-Zhen</p> <p>2017-12-01</p> <p>In late 2014 and early 2015, the canonical atmospheric response to the El Niño and Southern Oscillation (ENSO) event was not observed in the <span class="hlt">central</span> and eastern equatorial <span class="hlt">Pacific</span>, although Niño3.4 index exceeded the threshold for a weak El Niño. In an effort to understand why it was so, this study deconvoluted the observed 2014/15 December-January-February (DJF) mean sea surface temperature (SST), precipitation and 200 hPa stream function anomalies into the leading patterns related to the principal components of DJF SST variability. It is noted that the anomalies of these variables were primarily determined by the patterns related to two SST modes: one is the North <span class="hlt">Pacific</span> mode (NPM), and the other the ENSO mode. The NPM was responsible for the apparent lack of coupled air-sea relationship in the <span class="hlt">central</span> equatorial <span class="hlt">Pacific</span> and the east-west structure of the circulation anomalies over North America, while the ENSO mode linked to SSTs in the <span class="hlt">central</span> and eastern equatorial <span class="hlt">Pacific</span> as well as the circulation in the <span class="hlt">central</span> equatorial <span class="hlt">Pacific</span>. Further, the ENSO signal in DJF 2014/15 likely evolved from the NPM pattern in winter 2013/14. Its full development, however, was impeded by the easterly anomalies in the <span class="hlt">central</span> equatorial <span class="hlt">Pacific</span> that was associated with negative SST anomalies in the southeastern subtropical <span class="hlt">Pacific</span>. In addition, the analyses also indicates that the SST anomalies in the Niño3.4 region alone were not adequate for capturing the coupling of oceanic and atmospheric anomalies in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, due to the fact that this index cannot distinguish whether the SST anomaly in the Niño3.4 region is associated with the ENSO mode or NPM, or both.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25471884','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25471884"><span>Eastern <span class="hlt">Pacific</span> <span class="hlt">tropical</span> cyclones intensified by El Niño delivery of subsurface ocean heat.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Jin, F-F; Boucharel, J; Lin, I-I</p> <p>2014-12-04</p> <p>The El Niño Southern Oscillation (ENSO) creates strong variations in sea surface temperature in the eastern equatorial <span class="hlt">Pacific</span>, leading to major climatic and societal impacts. In particular, ENSO influences the yearly variations of <span class="hlt">tropical</span> cyclone (TC) activities in both the <span class="hlt">Pacific</span> and Atlantic basins through atmospheric dynamical factors such as vertical wind shear and stability. Until recently, however, the direct ocean thermal control of ENSO on TCs has not been taken into consideration because of an apparent mismatch in both timing and location: ENSO peaks in winter and its surface warming occurs mostly along the Equator, a region without TC activity. Here we show that El Niño--the warm phase of an ENSO cycle--effectively discharges heat into the eastern North <span class="hlt">Pacific</span> basin two to three seasons after its wintertime peak, leading to intensified TCs. This basin is characterized by abundant TC activity and is the second most active TC region in the world. As a result of the time involved in ocean transport, El Niño's equatorial subsurface 'heat reservoir', built up in boreal winter, appears in the eastern North <span class="hlt">Pacific</span> several months later during peak TC season (boreal summer and autumn). By means of this delayed ocean transport mechanism, ENSO provides an additional heat supply favourable for the formation of strong hurricanes. This thermal control on intense TC variability has significant implications for seasonal predictions and long-term projections of TC activity over the eastern North <span class="hlt">Pacific</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/1432724-role-convective-gustiness-reducing-seasonal-precipitation-biases-tropical-west-pacific','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/1432724-role-convective-gustiness-reducing-seasonal-precipitation-biases-tropical-west-pacific"><span>The Role of Convective Gustiness in Reducing Seasonal Precipitation Biases in the <span class="hlt">Tropical</span> West <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Harrop, Bryce E.; Ma, Po -Lun; Rasch, Philip J.</p> <p></p> <p>Precipitation is an important climate quantity that is critically relevant to society. In spite of intense efforts, significant precipitation biases remain in most climate models. One pervasive and persistent bias found in many general circulation models occurs in the <span class="hlt">Tropical</span> West <span class="hlt">Pacific</span> where northern hemisphere summer-time precipitation is often underestimated compared to observations. Using the DOE-E3SM model, the inclusion of a missing process, convective gustiness, is shown to reduce those biases through a net increase in surface evaporation. Gustiness in surface wind fields is assumed to arise empirically in proportion to the intensity of convective precipitation. The increased evaporation canmore » be treated as an increase in the moist static energy forcing into the atmosphere. A Normalized Gross Moist Stability (NGMS) framework (which characterizes the relationship between convective forcing and convective response) is used to explore the processes responsible for the precipitation bias, and the impact of the gustiness parameterization in reducing that bias. Because the NGMS of the <span class="hlt">Tropical</span> West <span class="hlt">Pacific</span> is less than unity in the E3SMv1 model, the increase in energy forcing amplifies the increase in precipitation to exceed that of the evaporative flux. Convective gustiness favors increased precipitation in regions where the resolved surface winds are weak and convection is present.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1432724-role-convective-gustiness-reducing-seasonal-precipitation-biases-tropical-west-pacific','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1432724-role-convective-gustiness-reducing-seasonal-precipitation-biases-tropical-west-pacific"><span>The Role of Convective Gustiness in Reducing Seasonal Precipitation Biases in the <span class="hlt">Tropical</span> West <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Harrop, Bryce E.; Ma, Po -Lun; Rasch, Philip J.; ...</p> <p>2018-03-12</p> <p>Precipitation is an important climate quantity that is critically relevant to society. In spite of intense efforts, significant precipitation biases remain in most climate models. One pervasive and persistent bias found in many general circulation models occurs in the <span class="hlt">Tropical</span> West <span class="hlt">Pacific</span> where northern hemisphere summer-time precipitation is often underestimated compared to observations. Using the DOE-E3SM model, the inclusion of a missing process, convective gustiness, is shown to reduce those biases through a net increase in surface evaporation. Gustiness in surface wind fields is assumed to arise empirically in proportion to the intensity of convective precipitation. The increased evaporation canmore » be treated as an increase in the moist static energy forcing into the atmosphere. A Normalized Gross Moist Stability (NGMS) framework (which characterizes the relationship between convective forcing and convective response) is used to explore the processes responsible for the precipitation bias, and the impact of the gustiness parameterization in reducing that bias. Because the NGMS of the <span class="hlt">Tropical</span> West <span class="hlt">Pacific</span> is less than unity in the E3SMv1 model, the increase in energy forcing amplifies the increase in precipitation to exceed that of the evaporative flux. Convective gustiness favors increased precipitation in regions where the resolved surface winds are weak and convection is present.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUFM.A11G..01K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFM.A11G..01K"><span>Sensitivity of South American <span class="hlt">tropical</span> climate to Last Glacial Maximum boundary conditions: focus on teleconnections with <span class="hlt">tropics</span> and extratropics (Invited)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Khodri, M.; Kageyama, M.; Roche, D. M.</p> <p>2009-12-01</p> <p> dynamical equilibrium due to both reduced GHG and land ice sheets. We also show that the overall <span class="hlt">tropical</span> <span class="hlt">Pacific</span> circulation response to land ice albedo alone consists in a substantial thermo-dynamical stabilisation of the equatorial atmosphere. The upper troposphere warming spreading out from South East <span class="hlt">Central</span> <span class="hlt">Pacific</span>, analogous to the atmosphere response to El-Niño conditions, results in enhanced rainfall over Nordeste and Southeastern Brazil. Such <span class="hlt">tropics-tropics</span> teleconnection is essential to explain the moistening of the southern <span class="hlt">tropics</span>, amplifying thereby the influence of the extratropical atmosphere on the LGM <span class="hlt">tropical</span> climate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5576648','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5576648"><span>Association of whale sharks (Rhincodon typus) with thermo-biological frontal systems of the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Green, Jonathan R.; Espinoza, Eduardo; Hearn, Alex R.</p> <p>2017-01-01</p> <p>Satellite tracking of 27 whale sharks in the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, examined in relation to environmental data, indicates preferential occupancy of thermo-biological frontal systems. In these systems, thermal gradients are caused by wind-forced circulation and mixing, and biological gradients are caused by associated nutrient enrichment and enhanced primary productivity. Two of the frontal systems result from upwelling, driven by divergence in the current systems along the equator and the west coast of South America; the third results from wind jet dynamics off <span class="hlt">Central</span> America. All whale sharks were tagged near Darwin Island, Galápagos, within the equatorial <span class="hlt">Pacific</span> upwelling system. Occupancy of frontal habitat is pronounced in synoptic patterns of shark locations in relation to serpentine, temporally varying thermal fronts across a zonal expanse > 4000 km. 80% of shark positions in northern equatorial upwelling habitat and 100% of positions in eastern boundary upwelling habitat were located within the upwelling front. Analysis of equatorial shark locations relative to thermal gradients reveals occupancy of a transition point in environmental stability. Equatorial subsurface tag data show residence in shallow, warm (>22°C) water 94% of the time. Surface zonal current speeds for all equatorial tracking explain only 16% of the variance in shark zonal movement speeds, indicating that passive drifting is not a primary determinant of movement patterns. Movement from equatorial to eastern boundary frontal zones occurred during boreal winter, when equatorial upwelling weakens seasonally. Off Peru sharks tracked upwelling frontal positions within ~100–350 km from the coast. Off <span class="hlt">Central</span> America, the largest tagged shark (12.8 m TL) occupied an oceanic front along the periphery of the Panama wind jet. Seasonal movement from waning equatorial upwelling to productive eastern boundary habitat is consistent with underlying trophic dynamics. Persistent shallow residence</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015BGD....12.4495L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015BGD....12.4495L"><span>Water column biogeochemistry of oxygen minimum zones in the eastern <span class="hlt">tropical</span> North Atlantic and eastern <span class="hlt">tropical</span> South <span class="hlt">Pacific</span> Oceans</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Löscher, C. R.; Bange, H. W.; Schmitz, R. A.; Callbeck, C. M.; Engel, A.; Hauss, H.; Kanzow, T.; Kiko, R.; Lavik, G.; Loginova, A.; Melzner, F.; Neulinger, S. C.; Pahlow, M.; Riebesell, U.; Schunck, H.; Thomsen, S.; Wagner, H.</p> <p>2015-03-01</p> <p>Recent modeling results suggest that oceanic oxygen levels will decrease significantly over the next decades to centuries in response to climate change and altered ocean circulation. Hence the future ocean may experience major shifts in nutrient cycling triggered by the expansion and intensification of <span class="hlt">tropical</span> oxygen minimum zones (OMZs). There are numerous feedbacks between oxygen concentrations, nutrient cycling and biological productivity; however, existing knowledge is insufficient to understand physical, chemical and biological interactions in order to adequately assess past and potential future changes. We investigated the pelagic biogeochemistry of OMZs in the eastern <span class="hlt">tropical</span> North Atlantic and eastern <span class="hlt">tropical</span> South <span class="hlt">Pacific</span> during a series of cruise expeditions and mesocosm studies. The following summarizes the current state of research on the influence of low environmental oxygen conditions on marine biota, viruses, organic matter formation and remineralization with a particular focus on the nitrogen cycle in OMZ regions. The impact of sulfidic events on water column biogeochemistry, originating from a specific microbial community capable of highly efficient carbon fixation, nitrogen turnover and N2O production is further discussed. Based on our findings, an important role of sinking particulate organic matter in controlling the nutrient stochiometry of the water column is suggested. These particles can enhance degradation processes in OMZ waters by acting as microniches, with sharp gradients enabling different processes to happen in close vicinity, thus altering the interpretation of oxic and anoxic environments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013NHESS..13..115W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013NHESS..13..115W"><span><span class="hlt">Tropical</span> cyclone-related socio-economic losses in the western North <span class="hlt">Pacific</span> region</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Welker, C.; Faust, E.</p> <p>2013-01-01</p> <p>The western North <span class="hlt">Pacific</span> (WNP) is the area of the world most frequently affected by <span class="hlt">tropical</span> cyclones (TCs). However, little is known about the socio-economic impacts of TCs in this region, probably because of the limited relevant loss data. Here, loss data from Munich RE's NatCatSERVICE database is used, a high-quality and widely consulted database of natural disasters. In the country-level loss normalisation technique we apply, the original loss data are normalised to present-day exposure levels by using the respective country's nominal gross domestic product at purchasing power parity as a proxy for wealth. The main focus of our study is on the question of whether the decadal-scale TC variability observed in the Northwest <span class="hlt">Pacific</span> region in recent decades can be shown to manifest itself economically in an associated variability in losses. It is shown that since 1980 the frequency of TC-related loss events in the WNP exhibited, apart from seasonal and interannual variations, interdecadal variability with a period of about 22 yr - driven primarily by corresponding variations of Northwest <span class="hlt">Pacific</span> TCs. Compared to the long-term mean, the number of loss events was found to be higher (lower) by 14% (9%) in the positive (negative) phase of the decadal-scale WNP TC frequency variability. This was identified for the period 1980-2008 by applying a wavelet analysis technique. It was also possible to demonstrate the same low-frequency variability in normalised direct economic losses from TCs in the WNP region. The identification of possible physical mechanisms responsible for the observed decadal-scale Northwest <span class="hlt">Pacific</span> TC variability will be the subject of future research, even if suggestions have already been made in earlier studies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMPP43D..05K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMPP43D..05K"><span>Using multi-resolution proxies to assess ENSO impacts on the mean state of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Karamperidou, C.; Conroy, J. L.</p> <p>2016-12-01</p> <p>Observations and model simulations indicate that the relationship between ENSO and the mean state of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> is a two-way interaction. On one hand, a strong zonal SST gradient (dSST) in the <span class="hlt">Pacific</span> (colder cold tongue) increases the potential intensity of upcoming ENSO events and may lead to increased ENSO variance. On the other hand, in a period of increased ENSO activity, large events can warm the cold tongue at decadal scales via residual heating, and thus lead to reduced zonal SST gradient (ENSO rectification mechanism). The short length of the observational record hinders our ability to confidently evaluate which mechanism dominates in each period, and whether it is sensitive to external climate forcing. This question is effectively a question of interaction between two timescales: interannual and decadal. Paleoclimate proxies of different resolutions can help elucidate this question, since they can be independent records of variability in these separate timescales. Here, we use coral proxies of ENSO variability from across the <span class="hlt">Pacific</span> and multi-proxy records of dSST at longer timescales. Proxies, models, and observations indicate that in periods of increased ENSO activity, dSST is negatively correlated with ENSO variance at decadal timescales, indicating that strong ENSO events may affect the decadal mean state via warming the cold tongue. Using climate model simulations we attribute this effect to residual nonlinear dynamical heating, thus supporting the ENSO rectification mechanism. On the contrary, in periods without strong events, ENSO variance and dSST are positively correlated, which indicates that the primary mechanism at work is the effect of the mean state on ENSO. Our analysis also quantitatively identifies the regions where paleoclimate proxies are needed in order to reduce the existing uncertainties in ENSO-mean state interactions. Hence, this study is a synthesis of observations, model simulations and paleoclimate proxy evidence</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMPP33B1325R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMPP33B1325R"><span>Calibrating a Method for Reconstructing ENSO Variance in the Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Using Mg/Ca in Individual Planktic Foraminifera</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rongstad, B.; Marchitto, T. M., Jr.; Koutavas, A.; Mekik, F.</p> <p>2017-12-01</p> <p>El Niño Southern Oscillation (ENSO) is Earth's dominant mode of interannual climate variability, and is responsible for widespread climatic, ecological and societal impacts, such as reduced upwelling and fishery collapse in the eastern equatorial <span class="hlt">Pacific</span> during El Niño events. While corals offer high resolution records of paleo-ENSO, continuous and gap-free records for the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> are rare. Individual foraminifera analyses provide an opportunity to create continuous down-core records of ENSO through the construction and comparison of species-specific sea surface temperature (SST) distributions at different time periods; however, there has been little focus on calibrating this technique to modern ENSO conditions. Here, we present data from a core-top calibration of individual Mg/Ca measurements in planktic foraminifera in the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, using surface dweller G. ruber and thermocline dweller N. dutertrei. We convert the individual Mg/Ca measurements to inferred temperature distributions for each species, and then compare the distributions to modern day temperature characteristics including vertical structure, annual mean, seasonality, and interannual variability. ENSO variance is theoretically inferred from the tails of the distributions: El Niño events affect the warm tail and La Niña events affect the cool tail. Finally, we discuss the utility of individual measurements of Mg/Ca in planktic foraminifera to reconstruct ENSO in down-core sections.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA432612','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA432612"><span>Influence of Antarctic Oscillation on Intraseasonal Variability of Large-Scale Circulations Over the Western North <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2005-03-01</p> <p>quartiles, and thus locates the <span class="hlt">central</span> 50% of the data. The center bar through each box represents the persistence median. The whiskers extend away from...level of <span class="hlt">tropical</span> cyclone activity. Numerous factors (e.g., scarcity of observations over large ocean basins , various scales of motion present in the... <span class="hlt">central</span> South Indian Ocean, South <span class="hlt">Pacific</span> Ocean east of New Zealand, and South Atlantic Ocean near the Falkland Islands. The increased pressure gradient</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AdAtS..31.1305L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AdAtS..31.1305L"><span>Numerical experiments on the impact of spring north <span class="hlt">pacific</span> SSTA on NPO and unusually cool summers in Northeast China</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lian, Yi; Zhao, Bin; Shen, Baizhu; Li, Shangfeng; Liu, Gang</p> <p>2014-11-01</p> <p>A set of numerical experiments designed to analyze the oceanic forcing in spring show that the combined forcing of cold (warm) El Niño (La Niña) phases in the Niño4 region and sea surface temperature anomalies (SSTA) in the westerly drifts region would result in abnormally enhanced NorthEast Cold Vortex (NECV) activities in early summer. In spring, the <span class="hlt">central</span> equatorial <span class="hlt">Pacific</span> El Niño phase and westerly drift SSTA forcing would lead to the retreat of non-adiabatic waves, inducing elliptic low-frequency anomalies of <span class="hlt">tropical</span> air flows. This would enhance the anomalous cyclone-anticyclone-cyclone-anticyclone low-frequency wave train that propagates from the <span class="hlt">tropics</span> to the extratropics and further to the mid-high latitudes, constituting a major physical mechanism that contributes to the early summer circulation anomalies in the subtropics and in the North <span class="hlt">Pacific</span> mid-high latitudes. The <span class="hlt">central</span> equatorial <span class="hlt">Pacific</span> La Niña forcing in the spring would, on the one hand, induce teleconnection anomalies of high pressure from the Sea of Okhotsk to the Sea of Japan in early summer, and on the other hand indirectly trigger a positive low-frequency East Asia-<span class="hlt">Pacific</span> teleconnection (EAP) wave train in the lower troposphere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://images.nasa.gov/#/details-PIA03457.html','SCIGOVIMAGE-NASA'); return false;" href="https://images.nasa.gov/#/details-PIA03457.html"><span><span class="hlt">Pacific</span> Decadal Oscillation Still Rules in <span class="hlt">Pacific</span>; No Niño Anytime Soon</span></a></p> <p><a target="_blank" href="https://images.nasa.gov/">NASA Image and Video Library</a></p> <p></p> <p>2001-08-27</p> <p>These data, taken during a 10-day collection cycle ending August 18, 2001, show that above-normal sea-surface heights and warmer ocean temperatures still blanket the far-western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> and much of the north and south mid-<span class="hlt">Pacific</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70013415','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70013415"><span>Accumulation of organic matter in Cretaceous oxygen-deficient depositional environments in the <span class="hlt">central</span> <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Dean, W.E.; Claypool, G.E.; Thide, J.</p> <p>1984-01-01</p> <p>Complete records of organic-carbon-rich Cretaceous strata were continuouslycored on the flanks of the Mid-<span class="hlt">Pacific</span> Mountains and southern Hess Rise in the <span class="hlt">central</span> North <span class="hlt">Pacific</span> Ocean during DSDP Leg 62. Organic-carbon-rich laminated silicified limestones were deposited in the western Mid-<span class="hlt">Pacific</span> Mountains during the early Aptian, a time when that region was south of the equator and considerably shallower than at present. Organic-carbon-rich, laminated limestone on southern Hess Rise overlies volcanic basement and includes 136 m of stratigraphic section of late Albian to early Cenomanian age. This limestone unit was deposited rapidly as Hess Rise was passing under the equatorial high-productivity zone and was subsiding from shallow to intermediate depths. The association of volcanogenic components with organic-carbon-rich strata on Hess Rise in the Mid-<span class="hlt">Pacific</span> Mountains is striking and suggests that there was a coincidence of mid-plate volcanic activity and the production and accumulation of organic matter at intermediate water depths in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean during the middle Cretaceous. Pyrolysis assays and analyses of extractable hydrocarbons indicate that the organic matter in the limestone on Hess Rise is composed mainly of lipid-rich kerogen derived from aquatic marine organisms and bacteria. Limestones from the Mid-<span class="hlt">Pacific</span> Mountains generally contain low ratios of pyrolytic hydrocarbons to organic carbon and low hydrogen indices, suggesting that the organic matter may contain a significant proportion of land-derived material, possibly derived from numerous volcanic islands that must have existed before the area subsided. The organic carbon in all samples analyzed is isotopically light (??13C - 24 to - 29 per mil) relative to most modern rine organic carbon, and the lightest carbon is also the most lipid-rich. There is a positive linear correlation between sulfur and organic carbon in samples from Hess Rise and from the Mid-<span class="hlt">Pacific</span> Mountains. The slopes</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70145850','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70145850"><span>Plant invasions in protected areas of <span class="hlt">tropical</span> <span class="hlt">pacific</span> islands, with special reference to Hawaii</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Hughes, R. Flint; Meyer, Jean-Yves; Loope, Lloyd L.</p> <p>2013-01-01</p> <p>Isolated <span class="hlt">tropical</span> islands are notoriously vulnerable to plant invasions. Serious management for protection of native biodiversity in Hawaii began in the 1970s, arguably at Hawaii Volcanoes National Park. Concerted alien plant management began there in the 1980s and has in a sense become a model for protected areas throughout Hawaii and <span class="hlt">Pacific</span> Island countries and territories. We review the relative successes of their strategies and touch upon how their experience has been applied elsewhere. Protected areas in Hawaii are fortunate in having relatively good resources for addressing plant invasions, but many invasions remain intractable, and invasions from outside the boundaries continue from a highly globalised society with a penchant for horticultural novelty. There are likely few efforts in most <span class="hlt">Pacific</span> Islands to combat alien plant invasions in protected areas, but such areas may often have fewer plant invasions as a result of their relative remoteness and/or socio-economic development status. The greatest current needs for protected areas in this region may be for establishment of yet more protected areas, for better resources to combat invasions in <span class="hlt">Pacific</span> Island countries and territories, for more effective control methods including biological control programme to contain intractable species, and for meaningful efforts to address prevention and early detection of potential new invaders.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JGRC..119.4029F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JGRC..119.4029F"><span>How much does heat content of the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean modulate the South China Sea summer monsoon onset in the last four decades?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Feng, Junqiao; Hu, Dunxin</p> <p>2014-07-01</p> <p>The role of the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean heat content in the South China Sea summer monsoon (SCSSM) onset is investigated in the present paper, by using atmospheric data from NCEP and ocean subsurface temperature data from Japan Meteorology Agency. It is showed from the result that the heat content (HC) of the upper 400 m layer in the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> (WTP), especially in the region of (130°E-150°E, 0°N-14°N) in the last four decades, is a good predictive indicator for the SCSSM onset. Positive (negative) HC anomalies can induce a strong (weak) convection over the WTP, leading to stronger (weaker) Walker circulation and weaker (stronger) western North <span class="hlt">Pacific</span> subtropical high (WNPSH) in the boreal spring. Consequently, the anomalous westerly (easterly) in the <span class="hlt">tropical</span> Indian Ocean is favorable (unfavorable) for the airflow into the SCS and for an early (late) WNPSH retreat from the SCS and hence for an early (late) SCSSM onset. It is elucidated that the long-term trend of SCSSM onset changes its sign around 1993/94 from decline to rise, which is responding and attributed to the WTP HC trend. During the period of 1971-1993, the WTP HC shows a significant decrease trend. In particular, a significant decline trend is observed in the HC difference between the WTP and western <span class="hlt">tropical</span> Indian Ocean, which causes an easterly trend in the SCS and strengthened WNPSH trend, leading to a late onset trend of SCSSM. The situation is reverse after 1993/94.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29844498','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29844498"><span>Patterns of species richness and the center of diversity in modern Indo-<span class="hlt">Pacific</span> larger foraminifera.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Förderer, Meena; Rödder, Dennis; Langer, Martin R</p> <p>2018-05-29</p> <p>Symbiont-bearing Larger Benthic Foraminifera (LBF) are ubiquitous components of shallow <span class="hlt">tropical</span> and subtropical environments and contribute substantially to carbonaceous reef and shelf sediments. Climate change is dramatically affecting carbonate producing organisms and threatens the diversity and structural integrity of coral reef ecosystems. Recent invertebrate and vertebrate surveys have identified the Coral Triangle as the planet's richest center of marine life delineating the region as a top priority for conservation. We compiled and analyzed extensive occurrence records for 68 validly recognized species of LBF from the Indian and <span class="hlt">Pacific</span> Ocean, established individual range maps and applied Minimum Convex Polygon (MCP) and Species Distribution Model (SDM) methodologies to create the first ocean-wide species richness maps. SDM output was further used for visualizing latitudinal and longitudinal diversity gradients. Our findings provide strong support for assigning the <span class="hlt">tropical</span> <span class="hlt">Central</span> Indo-<span class="hlt">Pacific</span> as the world's species-richest marine region with the <span class="hlt">Central</span> Philippines emerging as the bullseye of LBF diversity. Sea surface temperature and nutrient content were identified as the most influential environmental constraints exerting control over the distribution of LBF. Our findings contribute to the completion of worldwide research on <span class="hlt">tropical</span> marine biodiversity patterns and the identification of targeting centers for conservation efforts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19800020491','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19800020491"><span><span class="hlt">Tropical</span> cyclone intensities from satellite microwave data</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Vonderhaar, T. H.; Kidder, S. Q.</p> <p>1980-01-01</p> <p>Radial profiles of mean 1000 mb to 250 mb temperature from the Nimbus 6 scanning microwave spectrometer (SCAMS) were constructed around eight intensifying <span class="hlt">tropical</span> storms in the western <span class="hlt">Pacific</span>. Seven storms showed distinct inward temperature gradients required for intensification; the eighth displayed no inward gradient and was decaying 24 hours later. The possibility that satellite data might be used to forecast <span class="hlt">tropical</span> cyclone turning motion was investigated using estimates obtained from Nimbus 6 SCAMS data tapes of the mean 1000 mb to 250 mb temperature field around eleven <span class="hlt">tropical</span> storms in 1975. Analysis of these data show that for turning storms, in all but one case, the turn was signaled 24 hours in advance by a significant temperature gradient perpendicular to the storm's path, at a distance of 9 deg to 13 deg in front of the storm. A thresholding technique was applied to the North <span class="hlt">Central</span> U.S. during the summer to estimate precipitation frequency. except</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://images.nasa.gov/#/details-S75-29719.html','SCIGOVIMAGE-NASA'); return false;" href="https://images.nasa.gov/#/details-S75-29719.html"><span>ASTP Apollo Command Module nears touchdown in <span class="hlt">Central</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="https://images.nasa.gov/">NASA Image and Video Library</a></p> <p></p> <p>1975-07-24</p> <p>S75-29719 (24 July 1975) --- The ASTP Apollo Command Module, with astronauts Thomas P. Stafford, Vance D. Brand and Donald K. Slayton aboard, nears a touchdown in the <span class="hlt">Central</span> <span class="hlt">Pacific</span> Ocean to conclude the historic joint U.S.-USSR Apollo-Soyuz Test Project docking mission in Earth orbit. The spacecraft splashed down in the Hawaiian Islands area at 4:18 p.m. (CDT), July 24, 1975.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMOS51B0974O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMOS51B0974O"><span>Influence of hydrography of <span class="hlt">Central</span> Mexican <span class="hlt">Pacific</span> in the spatial variation of inorganic nutrients during 2010</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Olivos-Ortiz, A.; Gaviño-Rodríguez, J. H.; Quijano-Scheggia, S.; Pelayo-Martinez, G.; Torres-Orozco, E.; Calva-Chavez, M.</p> <p>2014-12-01</p> <p>The Mexican <span class="hlt">Central</span> <span class="hlt">Pacific</span> (MCP) is considered an oligotrophic area that holds important populations of different species with ecological and economic importance like marine mammals, billfish and tunas. Hydrographic mechanisms are responsible to interplay with the biogeochemical cycles of nutrients to support primary productivity for these food webs. It is argued that seasonal upwelling of bottom waters rich in nutrients generates distributed in patches of high-productivity, which are also linked to topographic continental forcing. The goal of this study is determine the presence of water masses, depth of the mixed layer, temperature, salinity, patterns of geostrophic currents and their influence on the spatiotemporal variability of inorganic nutrients. For that pupose, three oceanographic cruises were conducted in January, May-June, and October of 2010 off the coast of the MCP. Each campaign consisted of 15 stations in five perpendicular transects with stations at 2, 50 and 100 nm offshore. At each station samples were taken to determine the concentration of NO3-+ NO2-, NH4+, PO43- and SiO2 at 0, 10, 25, 50, 75, 100, 150 and 200 m depth. CTD casts were made up to 500m to obtain profiles of salinity, temperature, water masses, and identify geostrophic currents (direction and intensity). Identified water masses were: <span class="hlt">Pacific</span> <span class="hlt">Tropical</span> Surface Water (PTSW), <span class="hlt">Pacific</span> Equatorial Surface Water (PESW), Equatorial <span class="hlt">Pacific</span> Water (EPW), California Current Water (CCW), Subtropical Subsurface Water (STSsW), and <span class="hlt">Pacific</span> Intermediate Water (PIT); these water masses were present in all three seasons being more clear the presence of CCW during autumn and PTSW in winter. The interaction between coastal topography, geostrophic circulation, and the depth of the mixed layer (55m oceanic part in January and 10m coastal area in October) were the factors that determined the location of areas of high concentration of nutrients. The distribution of nutrients was heterogeneous</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3496911','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3496911"><span>Redescription of the poorly known planktonic copepod Pontellopsis lubbockii (Giesbrecht, 1889) (Pontellidae) from the Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> with a key to species</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Suárez-Morales, Eduardo; Kozak, Eva</p> <p>2012-01-01</p> <p>Abstract During a survey of the epipelagic zooplankton carried out off the coast of the Mexican states of Jalisco and Colima, in the Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span>, female and male specimens of the poorly known calanoid copepod Pontellopsis lubbockii (Giesbrecht, 1889) were collected. Because previous descriptions and illustrations are largely incomplete and have caused some taxonomical confusion, this species is fully redescribed from specimens from the Mexican <span class="hlt">Pacific</span>. The species has some characters that have been overlooked, but those related to the female genital double-somite are the most striking, it has two conical dorsal protuberances and a long ventral spiniform process unique of this species. The mouthparts of this species have not been hitherto described and figured, the flexible terminal setae of legs 3 and 4 is noteworthy. The male general morphology agrees in general with previous data, but new details of the leg 5 and geniculate antennule are added. Its mouthparts, with strong, serrate setae on the maxillae and maxillules, and a strong mandibular edge, suggest that this is a predator form. A dichotomous key for the identification of males and females of the species of Pontellopsis known from the Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> is included. PMID:23372406</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27698122','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27698122"><span>Simple dynamical models capturing the key features of the <span class="hlt">Central</span> <span class="hlt">Pacific</span> El Niño.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chen, Nan; Majda, Andrew J</p> <p>2016-10-18</p> <p>The <span class="hlt">Central</span> <span class="hlt">Pacific</span> El Niño (CP El Niño) has been frequently observed in recent decades. The phenomenon is characterized by an anomalous warm sea surface temperature (SST) confined to the <span class="hlt">central</span> <span class="hlt">Pacific</span> and has different teleconnections from the traditional El Niño. Here, simple models are developed and shown to capture the key mechanisms of the CP El Niño. The starting model involves coupled atmosphere-ocean processes that are deterministic, linear, and stable. Then, systematic strategies are developed for incorporating several major mechanisms of the CP El Niño into the coupled system. First, simple nonlinear zonal advection with no ad hoc parameterization of the background SST gradient is introduced that creates coupled nonlinear advective modes of the SST. Secondly, due to the recent multidecadal strengthening of the easterly trade wind, a stochastic parameterization of the wind bursts including a mean easterly trade wind anomaly is coupled to the simple atmosphere-ocean processes. Effective stochastic noise in the wind burst model facilitates the intermittent occurrence of the CP El Niño with realistic amplitude and duration. In addition to the anomalous warm SST in the <span class="hlt">central</span> <span class="hlt">Pacific</span>, other major features of the CP El Niño such as the rising branch of the anomalous Walker circulation being shifted to the <span class="hlt">central</span> <span class="hlt">Pacific</span> and the eastern <span class="hlt">Pacific</span> cooling with a shallow thermocline are all captured by this simple coupled model. Importantly, the coupled model succeeds in simulating a series of CP El Niño that lasts for 5 y, which resembles the two CP El Niño episodes during 1990-1995 and 2002-2006.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ClDy...50.1471K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ClDy...50.1471K"><span>Model under-representation of decadal <span class="hlt">Pacific</span> trade wind trends and its link to <span class="hlt">tropical</span> Atlantic bias</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kajtar, Jules B.; Santoso, Agus; McGregor, Shayne; England, Matthew H.; Baillie, Zak</p> <p>2018-02-01</p> <p>The strengthening of the <span class="hlt">Pacific</span> trade winds in recent decades has been unmatched in the observational record stretching back to the early twentieth century. This wind strengthening has been connected with numerous climate-related phenomena, including accelerated sea-level rise in the western <span class="hlt">Pacific</span>, alterations to Indo-<span class="hlt">Pacific</span> ocean currents, increased ocean heat uptake, and a slow-down in the rate of global-mean surface warming. Here we show that models in the Coupled Model Intercomparison Project phase 5 underestimate the observed range of decadal trends in the <span class="hlt">Pacific</span> trade winds, despite capturing the range in decadal sea surface temperature (SST) variability. Analysis of observational data suggests that <span class="hlt">tropical</span> Atlantic SST contributes considerably to the <span class="hlt">Pacific</span> trade wind trends, whereas the Atlantic feedback in coupled models is muted. Atmosphere-only simulations forced by observed SST are capable of recovering the time-variation and the magnitude of the trade wind trends. Hence, we explore whether it is the biases in the mean or in the anomalous SST patterns that are responsible for the under-representation in fully coupled models. Over interannual time-scales, we find that model biases in the patterns of Atlantic SST anomalies are the strongest source of error in the precipitation and atmospheric circulation response. In contrast, on decadal time-scales, the magnitude of the model biases in Atlantic mean SST are directly linked with the trade wind variability response.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUOSPC53A..07L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUOSPC53A..07L"><span>Atlantic Induced Pan-<span class="hlt">tropical</span> Climate Variability in the Upper-ocean and Atmosphere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, X.; Xie, S. P.; Gille, S. T.; Yoo, C.</p> <p>2016-02-01</p> <p>During the last three decades, <span class="hlt">tropical</span> sea surface temperature (SST) exhibited dipole-like trends, with warming over the <span class="hlt">tropical</span> Atlantic and Indo-Western <span class="hlt">Pacific</span> but cooling over the Eastern <span class="hlt">Pacific</span>. The Eastern <span class="hlt">Pacific</span> cooling has recently been identified as a driver of the global warming hiatus. Previous studies revealed atmospheric bridges between the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, Atlantic, and Indian Ocean, which could potentially contribute to this zonally asymmetric SST pattern. However, the mechanisms and the interactions between these teleconnections remain unclear. To investigate these questions, we performed a `pacemaker' simulation by restoring the <span class="hlt">tropical</span> Atlantic SST changes in a state-of-the-art climate model - the CESM1. Results show that the Atlantic plays a key role in initiating the <span class="hlt">tropical</span>-wide teleconnections, and the Atlantic-induced anomalies contribute 55%-75% of the total <span class="hlt">tropical</span> SST and circulation changes during the satellite era. A hierarchy of oceanic and atmospheric models are then used to investigate the physical mechanisms of these teleconnections: the Atlantic warming enhances atmospheric deep convection, drives easterly wind anomalies over the Indo-Western <span class="hlt">Pacific</span> through the Kelvin wave, and westerly anomalies over the eastern <span class="hlt">Pacific</span> as Rossby waves, in line with Gill's solution (Fig1a). These wind changes induce an Indo-Western <span class="hlt">Pacific</span> warming via the wind-evaporation-SST effect, and this warming intensifies the La Niña-type response in the upper <span class="hlt">Pacific</span> Ocean by enhancing the easterly trade winds and through the Bjerknes ocean-dynamical processes (Fig1b). The teleconnection finally develops into a <span class="hlt">tropical</span>-wide SST dipole pattern with an enhanced trade wind and Walker circulation, similar as the observed changes during the satellite era. This mechanism reveals that the <span class="hlt">tropical</span> ocean basins are more tightly connected than previously thought, and the Atlantic plays a key role in the <span class="hlt">tropical</span> climate pattern formation and further the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JMetR..31..987L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JMetR..31..987L"><span>Theories on formation of an anomalous anticyclone in western North <span class="hlt">Pacific</span> during El Niño: A review</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Tim; Wang, Bin; Wu, Bo; Zhou, Tianjun; Chang, Chih-Pei; Zhang, Renhe</p> <p>2017-12-01</p> <p>The western North <span class="hlt">Pacific</span> anomalous anticyclone (WNPAC) is an important atmospheric circulation system that conveys El Niño impact on East Asian climate. In this review paper, various theories on the formation and maintenance of the WNPAC, including warm pool atmosphere-ocean interaction, Indian Ocean capacitor, a combination mode that emphasizes nonlinear interaction between ENSO and annual cycle, moist enthalpy advection/Rossby wave modulation, and <span class="hlt">central</span> <span class="hlt">Pacific</span> SST forcing, are discussed. It is concluded that local atmosphere-ocean interaction and moist enthalpy advection/Rossby wave modulation mechanisms are essential for the initial development and maintenance of the WNPAC during El Niño mature winter and subsequent spring. The Indian Ocean capacitor mechanism does not contribute to the earlier development but helps maintain the WNPAC in El Niño decaying summer. The cold SST anomaly in the western North <span class="hlt">Pacific</span>, although damped in the summer, also plays a role. An interbasin atmosphere-ocean interaction across the Indo-<span class="hlt">Pacific</span> warm pool emerges as a new mechanism in summer. In addition, the <span class="hlt">central</span> <span class="hlt">Pacific</span> cold SST anomaly may induce the WNPAC during rapid El Niño decaying/La Niña developing or La Niña persisting summer. The near-annual periods predicted by the combination mode theory are hardly detected from observations and thus do not contribute to the formation of the WNPAC. The <span class="hlt">tropical</span> Atlantic may have a capacitor effect similar to the <span class="hlt">tropical</span> Indian Ocean.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.A21I2266A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.A21I2266A"><span>Seasonal Differences in <span class="hlt">Tropical</span> Western <span class="hlt">Pacific</span> Cloud Ice, Water Vapor and Aerosols Observed From Space During ATTREX-III and POSIDON</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Avery, M. A.; Rosenlof, K. H.; Vaughan, M.; Getzewich, B. J.; Thornberry, T. D.; Gao, R. S.; Rollins, A. W.; Woods, S.; Yorks, J. E.; Jensen, E. J.</p> <p>2017-12-01</p> <p>Recent aircraft missions sampling the <span class="hlt">tropical</span> tropopause layer (TTL) in the <span class="hlt">tropical</span> Western <span class="hlt">Pacific</span> have provided a wealth of detailed cloud microphysical and associated aerosol, water vapor and temperature data for understanding processes that regulate stratospheric composition and hydration. This presentation seeks to provide a regional context for these measurements by comparing and contrasting active space-based observations from these time periods (Feb-Mar 2014 for ATTREX-III and Oct 2016 for POSIDON), primarily from the Clouds and Aerosol Lidar with Orthogonal Polarization (CALIOP), with the addition of Cloud Profiling Radar (CPR) and the Cloud-Aerosol Transport System (CATS) where these data sets are available. While the ATTREX III and POSIDON aircraft field missions both took place from Guam in the Western <span class="hlt">Pacific</span>, there were striking differences between the amount, geographical distribution and properties of cirrus clouds and aerosols in the <span class="hlt">Tropical</span> TTL. In addition to cloud and aerosol amount and location, we present geometric properties, including cloud top heights, transparent cloud and aerosol layer thicknesses and location of the 532 nm backscatter centroid, which is roughly equivalent to the layer vertical center of mass. We also present differences in the distribution of cirrus cloud extinction coefficients and ice water content, and aerosol optical depths, as detected from space, and compare these with in situ measurements and with temperature and water vapor distributions from the Microwave Limb Sounder (MLS). We find that there is more intense convection reaching the <span class="hlt">tropical</span> tropopause during the POSIDON mission, and consequently more associated cloud ice observed during POSIDON than during ATTREX-III.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMPP22A..07G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMPP22A..07G"><span>Indo-<span class="hlt">Pacific</span> hydroclimate over the past millennium and links with global climate variabilty</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Griffiths, M. L.; Drysdale, R.; Kimbrough, A. K.; Hua, Q.; Johnson, K. R.; Gagan, M. K.; Cole, J. E.; Cook, B. I.; Zhao, J. X.; Hellstrom, J. C.; Hantoro, W. S.</p> <p>2016-12-01</p> <p> records from the <span class="hlt">central</span>-eastern equatorial <span class="hlt">Pacific</span> Ocean and western Indian Ocean, and eastern Australia), and thus, the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> may have played a critical role in amplifying the radiative-forced global cooling already underway.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28931881','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28931881"><span>Contrasting subtropical PV intrusion frequency and their impact on tropospheric Ozone distribution over <span class="hlt">Pacific</span> Ocean in El-Niño and La-Niña conditions.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Nath, Debashis; Chen, Wen; Graf, Hans-F; Lan, Xiaoqiang; Gong, Hainan</p> <p>2017-09-20</p> <p>Upper tropospheric equatorial westerly ducts over the <span class="hlt">Pacific</span> Ocean are the preferred location for Rossby wave breaking events during boreal winter and spring. These subtropical wave breaking events lead to the intrusion of high PV (potential vorticity) air along the extra-<span class="hlt">tropical</span> tropopause and transport ozone rich dry stratospheric air into the <span class="hlt">tropics</span>. The intrusion frequency has strong interannual variability due to ENSO (El-Niño/Southern Oscillation), with more events under La-Niña and less under El-Niño conditions. This may result from stronger equatorial westerly ducts and subtropical jets during La-Niña and weaker during El-Niño. It was previously suggested that the interannual variability of the tropospheric ozone distribution over the <span class="hlt">central</span>-eastern <span class="hlt">Pacific</span> Ocean is mainly driven by convective activity related to ENSO and that the barotropic nature of the subtropical intrusions restricts the tracers within the UT. However, our analysis shows that tropospheric ozone concentration and subtropical intrusions account ~65% of the co- variability (below 5 km) in the outer <span class="hlt">tropical</span> (10-25°N) <span class="hlt">central</span> <span class="hlt">Pacific</span> Ocean, particularly during La-Niña conditions. Additionally, we find a two-fold increase and westward shift in the intrusion frequency over the <span class="hlt">Pacific</span> Ocean, due to the climate regime shift in SST pattern during 1997/98.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ClDy...49.3787P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ClDy...49.3787P"><span>Interannual variability of western North <span class="hlt">Pacific</span> SST anomalies and its impact on North <span class="hlt">Pacific</span> and North America</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Park, Jae-Heung; An, Soon-Il; Kug, Jong-Seong</p> <p>2017-12-01</p> <p>In this study, the interannual variability of sea surface temperature (SST) and its atmospheric teleconnection over the western North <span class="hlt">Pacific</span> (WNP) toward the North <span class="hlt">Pacific</span>/North America during boreal winter are investigated. First, we defined the WNP mode as the first empirical orthogonal function (EOF) mode of SST anomalies over the WNP region (100-165°E, 0-35°N), of which the principle component time-series are significantly correlated with several well-known climate modes such as the warm pool mode which is the second EOF mode of the <span class="hlt">tropical</span> to North <span class="hlt">Pacific</span> SST anomalies, North <span class="hlt">Pacific</span> oscillation (NPO), North <span class="hlt">Pacific</span> gyre oscillation (NPGO), and <span class="hlt">central</span> <span class="hlt">Pacific</span> (CP)-El Niño at 95% confidence level, but not correlated with the eastern <span class="hlt">Pacific</span> (EP)-El Niño. The warm phase of the WNP mode (sea surface warming) is initiated by anomalous southerly winds through reduction of wind speed with the background of northerly mean winds over the WNP during boreal winter, i.e., reduced evaporative cooling. Meanwhile, the atmospheric response to the SST warming pattern and its diabatic heating further enhance the southerly wind anomaly, referred to the wind-evaporation-SST (WES) feedback. Thus, the WNP mode is developed and maintained through winter until spring, when the northerly mean wind disappears. Furthermore, it is also known that anomalous upper-level divergence associated with WNP mode leads to the NPO-like structure over the North <span class="hlt">Pacific</span> and the east-west pressure contrast pattern over the North America through Rossby wave propagation, impacting the climate over the North <span class="hlt">Pacific</span> and North America.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20160006463','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20160006463"><span>The ENSO Effects on <span class="hlt">Tropical</span> Clouds and Top-of-Atmosphere Cloud Radiative Effects in CMIP5 Models</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Su, Wenying; Wang, Hailan</p> <p>2015-01-01</p> <p>The El Nino-Southern Oscillation (ENSO) effects on <span class="hlt">tropical</span> clouds and top-of-atmosphere (TOA) cloud radiative effects (CREs) in Coupled Model Intercomparison Project Phase5 (CMIP5) models are evaluated using satellite-based observations and International Satellite Cloud Climatology Project satellite simulator output. Climatologically, most CMIP5 models produce considerably less total cloud amount with higher cloud top and notably larger reflectivity than observations in <span class="hlt">tropical</span> Indo-<span class="hlt">Pacific</span> (60 degrees East - 200 degrees East; 10 degrees South - 10 degrees North). During ENSO, most CMIP5 models considerably underestimate TOA CRE and cloud changes over western <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. Over <span class="hlt">central</span> <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, while the multi-model mean resembles observations in TOA CRE and cloud amount anomalies, it notably overestimates cloud top pressure (CTP) decreases; there are also substantial inter-model variations. The relative effects of changes in cloud properties, temperature and humidity on TOA CRE anomalies during ENSO in the CMIP5 models are assessed using cloud radiative kernels. The CMIP5 models agree with observations in that their TOA shortwave CRE anomalies are primarily contributed by total cloud amount changes, and their TOA longwave CRE anomalies are mostly contributed by changes in both total cloud amount and CTP. The model biases in TOA CRE anomalies particularly the strong underestimations over western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> are, however, mainly explained by model biases in CTP and cloud optical thickness (tau) changes. Despite the distinct model cloud biases particularly in tau regime, the TOA CRE anomalies from cloud amount changes are comparable between the CMIP5 models and observations, because of the strong compensations between model underestimation of TOA CRE anomalies from thin clouds and overestimation from medium and thick clouds.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018GeoRL..45.4238B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018GeoRL..45.4238B"><span>Increasing Magnitude of Hurricane Rapid Intensification in the <span class="hlt">Central</span> and Eastern <span class="hlt">Tropical</span> Atlantic</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Balaguru, Karthik; Foltz, Gregory R.; Leung, L. Ruby</p> <p>2018-05-01</p> <p>Rapid intensification (RI) of hurricanes is notoriously difficult to predict and can contribute to severe destruction and loss of life. While past studies examined the frequency of RI occurrence, changes in RI magnitude were not considered. Here we explore changes in RI magnitude over the 30-year satellite period of 1986-2015. In the <span class="hlt">central</span> and eastern <span class="hlt">tropical</span> Atlantic, which includes much of the main development region, the 95th percentile of 24-hr intensity changes increased at 3.8 knots per decade. In the western <span class="hlt">tropical</span> Atlantic, encompassing the Caribbean Sea and the Gulf of Mexico, trends are insignificant. Our analysis reveals that warming of the upper ocean coinciding with the positive phase of Atlantic Multidecadal Oscillation, and associated changes in the large-scale environment, has predominantly favored RI magnitude increases in the <span class="hlt">central</span> and eastern <span class="hlt">tropical</span> Atlantic. These results have substantial implications for the eastern Caribbean Islands, some of which were devastated during the 2017 hurricane season.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/FR-2013-04-19/pdf/2013-09242.pdf','FEDREG'); return false;" href="https://www.gpo.gov/fdsys/pkg/FR-2013-04-19/pdf/2013-09242.pdf"><span>78 FR 23633 - Union <span class="hlt">Pacific</span> Railroad Company-Trackage Rights Exemption-Illinois <span class="hlt">Central</span> Railroad Company</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR">Federal Register 2010, 2011, 2012, 2013, 2014</a></p> <p></p> <p>2013-04-19</p> <p>... Railroad Company--Trackage Rights Exemption-- Illinois <span class="hlt">Central</span> Railroad Company Illinois <span class="hlt">Central</span> Railroad... trackage rights to Union <span class="hlt">Pacific</span> Railroad Company (UP) over IC's Chicago Subdivision between milepost 21.0... predecessor railroads, it currently maintains trackage rights over approximately 60 miles of IC's rail line...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70010137','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70010137"><span>Latitudinal gradients in tertiary molluscan faunas of the <span class="hlt">Pacific</span> coast</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Addicott, W.O.</p> <p>1970-01-01</p> <p>Tertiary molluscan faunas of the middle latitudes of the marginal eastern North <span class="hlt">Pacific</span> are characterized by warm-water taxa whose descendants now live in more southerly latitudes. A series of profiles in which cumulative percentages of warm-water faunal elements are plotted against latitude show progressive northward decreases in the percentage of these elements in the faunas of <span class="hlt">Pacific</span> coast Tertiary stages. Systematic changes in the relative position of these latitudinal gradients during the Middle and Late Tertiary are related to climatic change in the <span class="hlt">Pacific</span> Basin. Widespread <span class="hlt">tropical</span> marine climate in the middle latitudes of the eastern North <span class="hlt">Pacific</span> during the Eocene is indicated by widespread faunal units characterized by high levels of taxonomic diversity. Succeeding Early Oligocene faunas are less diverse, suggesting cooler climatic conditions. Unusually low representations of warm-water genera characterize the molluscan faunas of the Acila shumardi Zone in <span class="hlt">central</span> California (latitude 34??-37??N). The anomalously cool-water aspect of these faunas may record the occurrence of upwelling along a bold linear segment of the <span class="hlt">Pacific</span> coast. During the Late Oligocene or the Early Miocene, they are replaced by faunas of unusually warm-water aspect resulting in positive anomalies in Miocene latitudinal faunal gradients in <span class="hlt">central</span> California. The Miocene anomalies seem to result from the development of an irregular Neogene coastline with extensive, newly established shallow-water embayments. ?? 1970.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011GeCoA..75..460W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011GeCoA..75..460W"><span>Dissolved iron anomaly in the deep <span class="hlt">tropical</span>-subtropical <span class="hlt">Pacific</span>: Evidence for long-range transport of hydrothermal iron</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wu, Jingfeng; Wells, Mark L.; Rember, Robert</p> <p>2011-01-01</p> <p>Dissolved iron profiles along a north-south transect along 158°W in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> show evidence of two deepwater anomalies. The first extends from Station ALOHA (22.78°N) to the equator at ˜1000-1500 m and lies below the maximum apparent oxygen utilization and nutrient (N, P) concentrations. The feature is not supported by vertical export processes, but instead corresponds with the lateral dilution field of δ 3He derived from the Loihi seamount, Hawaii, though a sediment source associated with the Hawaiian Island Chain cannot be entirely ruled out. The second, deeper (2000-3000 m) anomaly occurs in <span class="hlt">tropical</span> South <span class="hlt">Pacific</span> waters (7°S) and also does not correlate with the depths of maximum nutrient concentrations or apparent oxygen utilization, but it does coincide closely with δ 3He emanating from the East <span class="hlt">Pacific</span> Rise, more than 5000 km to the east. We hypothesize that these anomalies represent the long-range (>2000 km) transport of hydrothermal iron residuals, stabilized against scavenging by complexation with excess organic ligands in the plume source regions. Such trace leakage of hydrothermal iron to distal plume regions would have been difficult to identify in most hydrothermal vent mapping studies because low analytical detection limits were not needed for the proximal plume regions. These findings suggest that hydrothermal activity may represent a major source of dissolved iron throughout the South <span class="hlt">Pacific</span> deep basin today, as well as other regions having high mid-ocean spreading rates in the geologic past. In particular, we hypothesize that high spreading rates along the South Atlantic and Southern Ocean mid-oceanic ridges, combined with the upwelling ventilation of these distal hydrothermal plumes, may have increased ocean productivity and carbon export in the Southern Ocean. Assessing the magnitude and persistence of dissolved hydrothermal iron in basin scale deep waters will be important for understanding the marine biogeochemistry of iron</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFMPP51A1582S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFMPP51A1582S"><span>Holocene Climate Variability in the <span class="hlt">Central</span> North <span class="hlt">Pacific</span>: An Organic Geochemical Record from Ka'au Crater Swamp, O'ahu, Hawai'i</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Street, J. H.; Beilman, D.; Timmermann, A.; Gaidos, E.; Paytan, A.</p> <p>2010-12-01</p> <p>North <span class="hlt">Pacific</span> climate is known to have varied during the Holocene, with significant “downstream” effects on the regional climate and hydrology of western North America. Evidence from paleoclimatic studies along the northeast <span class="hlt">Pacific</span> margin hints at several broad-scale regime shifts since the early Holocene, with spatial expressions analogous to those observed during phase shifts of the modern ENSO and PDO, though occurring on much longer (centennial to millennial) timescales. Nonetheless, the timing, magnitude and spatial patterns of Holocene rearrangements in oceanic and atmospheric circulation in the North <span class="hlt">Pacific</span> remain incompletely defined. The main Hawaiian Islands (19 - 22 °N, 155 - 160 °W) are uniquely situated to “sample” climate variability in the subtropical, <span class="hlt">central</span> North <span class="hlt">Pacific</span>. Precipitation in Hawai’i is strongly influenced by the seasonal migration of the <span class="hlt">Pacific</span> Anticyclone and the associated trade winds, and, during the winter, the frequency and intensity of westerly moisture-bearing storms. On interannual to decadal timescales, basin-wide circulation changes related to ENSO and PDO modulate trade wind strength and the occurrence of winter storm patterns, leading to local variations in precipitation. Terrestrial paleoclimatic records from Hawai’i are rare, but of great potential value to reconstruct aspects of <span class="hlt">central</span> North <span class="hlt">Pacific</span> atmospheric circulation during the Holocene, including the influence of the <span class="hlt">tropical</span> ENSO system. In this study we present initial results from a 4.5 m, ~14 kyr sedimentary sequence recovered from Ka’au Crater Swamp, located near the leeward crest of the Ko’olau range of southeastern O’ahu, in a zone of high precipitation (>330 cm/yr). We utilize carbon and nitrogen elemental abundances (TOC, TN, C/N) and isotopic compositions (δ13C, δ15N) of bulk organic matter and ratios of biomarker compounds to reconstruct changes in vegetation, organic matter sources, and biogeochemical cycling in relation to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.fs.usda.gov/treesearch/pubs/37809','TREESEARCH'); return false;" href="https://www.fs.usda.gov/treesearch/pubs/37809"><span>Taxonomy and remote sensing of leaf mass per area (LMA) in humid <span class="hlt">tropical</span> forests</span></a></p> <p><a target="_blank" href="http://www.fs.usda.gov/treesearch/">Treesearch</a></p> <p>Gregory P. Asner; Roberta E. Martin; Raul Tupayachi; Ruth Emerson; Paola Martinez; Felipe Sinca; George V.N. Powell; S. Joseph Wright; Ariel E. Lugo</p> <p>2011-01-01</p> <p>Leaf mass per area (LMA) is a trait of <span class="hlt">central</span> importance to plant physiology and ecosystem function, but LMA patterns in the upper canopies of humid <span class="hlt">tropical</span> forests have proved elusive due to tall species and high diversity. We collected top-of-canopy leaf samples from 2873 individuals in 57 sites spread across the Neotropics, Australasia, and Caribbean and <span class="hlt">Pacific</span>...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.fs.usda.gov/treesearch/pubs/45931','TREESEARCH'); return false;" href="https://www.fs.usda.gov/treesearch/pubs/45931"><span>Patterns of natural and anthropogenic disturbance of the mangroves on a small <span class="hlt">Pacific</span> island.</span></a></p> <p><a target="_blank" href="http://www.fs.usda.gov/treesearch/">Treesearch</a></p> <p>James A. Allen; Katherine C. Ewel; Jason Jack</p> <p>2001-01-01</p> <p>Mangroves in many parts of the world are subjected to frequent, large-scale disturbances. A possible exception is Kosrae, Federated States of Micronesia (FSM), a small volcanic island in the west-<span class="hlt">central</span> <span class="hlt">Pacific</span> Ocean. Relative sea level has been stable for most of the last 1000 years and the last <span class="hlt">tropical</span> cyclone to affect the island was in 1905. Many trees on Kosrae...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140013024','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140013024"><span>Contrasting Effects of <span class="hlt">Central</span> <span class="hlt">Pacific</span> and Eastern <span class="hlt">Pacific</span> El Nino on Stratospheric Water Vapor</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Garfinkel, Chaim I.; Hurwitz, Margaret M.; Oman, Luke D.; Waugh, Darryn W.</p> <p>2013-01-01</p> <p>Targeted experiments with a comprehensive chemistry-climate model are used to demonstrate that seasonality and the location of the peak warming of sea surface temperatures dictate the response of stratospheric water vapor to El Nino. In spring, El Nino events in which sea surface temperature anomalies peak in the eastern <span class="hlt">Pacific</span> lead to a warming at the tropopause above the warm pool region, and subsequently to more stratospheric water vapor (consistent with previous work). However, in fall and in early winter, and also during El Nino events in which the sea surface temperature anomaly is found mainly in the <span class="hlt">central</span> <span class="hlt">Pacific</span>, the response is qualitatively different: temperature changes in the warm pool region are nonuniform and less water vapor enters the stratosphere. The difference in water vapor in the lower stratosphere between the two variants of El Nino approaches 0.3 ppmv, while the difference between the winter and spring responses exceeds 0.5 ppmv.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19930049771&hterms=skills&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dskills','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19930049771&hterms=skills&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dskills"><span>An evaluation of the real-time <span class="hlt">tropical</span> cyclone forecast skill of the Navy Operational Global Atmospheric Prediction System in the western North <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fiorino, Michael; Goerss, James S.; Jensen, Jack J.; Harrison, Edward J., Jr.</p> <p>1993-01-01</p> <p>The paper evaluates the meteorological quality and operational utility of the Navy Operational Global Atmospheric Prediction System (NOGAPS) in forecasting <span class="hlt">tropical</span> cyclones. It is shown that the model can provide useful predictions of motion and formation on a real-time basis in the western North <span class="hlt">Pacific</span>. The meterological characteristics of the NOGAPS <span class="hlt">tropical</span> cyclone predictions are evaluated by examining the formation of low-level cyclone systems in the <span class="hlt">tropics</span> and vortex structure in the NOGAPS analysis and verifying 72-h forecasts. The adjusted NOGAPS track forecasts showed equitable skill to the baseline aid and the dynamical model. NOGAPS successfully predicted unusual equatorward turns for several straight-running cyclones.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005AdAtS..22..915Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005AdAtS..22..915Z"><span>South Asian high and Asian-<span class="hlt">Pacific</span>-American climate teleconnection</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Peiqun; Song, Yang; Kousky, Vernon E.</p> <p>2005-11-01</p> <p>Growing evidence indicates that the Asian monsoon plays an important role in affecting the weather and climate outside of Asia. However, this active role of the monsoon has not been demonstrated as thoroughly as has the variability of the monsoon caused by various impacting factors such as sea surface temperature and land surface. This study investigates the relationship between the Asian monsoon and the climate anomalies in the Asian-<span class="hlt">Pacific</span>-American (APA) sector. A hypothesis is tested that the variability of the upper-tropospheric South Asian high (SAH), which is closely associated with the overall heating of the large-scale Asian monsoon, is linked to changes in the subtropical western <span class="hlt">Pacific</span> high (SWPH), the mid-<span class="hlt">Pacific</span> trough, and the Mexican high. The changes in these circulation systems cause variability in surface temperature and precipitation in the APA region. A stronger SAH is accompanied by a stronger and more extensive SWPH. The enlargement of the SWPH weakens the mid-<span class="hlt">Pacific</span> trough. As a result, the southern portion of the Mexican high becomes stronger. These changes are associated with changes in atmospheric teleconnections, precipitation, and surface temperature throughout the APA region. When the SAH is stronger, precipitation increases in southern Asia, decreases over the <span class="hlt">Pacific</span> Ocean, and increases over the <span class="hlt">Central</span> America. Precipitation also increases over Australia and <span class="hlt">central</span> Africa and decreases in the Mediterranean region. While the signals in surface temperature are weak over the <span class="hlt">tropical</span> land portion, they are apparent in the mid latitudes and over the eastern <span class="hlt">Pacific</span> Ocean.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/FR-2012-02-15/pdf/2012-3546.pdf','FEDREG'); return false;" href="https://www.gpo.gov/fdsys/pkg/FR-2012-02-15/pdf/2012-3546.pdf"><span>77 FR 8759 - International Fisheries; Western and <span class="hlt">Central</span> <span class="hlt">Pacific</span> Fisheries for Highly Migratory Species...</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR">Federal Register 2010, 2011, 2012, 2013, 2014</a></p> <p></p> <p>2012-02-15</p> <p>... Convention on the Conservation and Management of Highly Migratory Fish Stocks in the Western and <span class="hlt">Central</span>... Management Area'' (Eastern SMA) and requirements relating to discards from purse seine fishing vessels. This... and Management of Highly Migratory Fish Stocks in the Western and <span class="hlt">Central</span> <span class="hlt">Pacific</span> Ocean (Commission or...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25225388','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25225388"><span>Functional over-redundancy and high functional vulnerability in global fish faunas on <span class="hlt">tropical</span> reefs.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mouillot, David; Villéger, Sébastien; Parravicini, Valeriano; Kulbicki, Michel; Arias-González, Jesus Ernesto; Bender, Mariana; Chabanet, Pascale; Floeter, Sergio R; Friedlander, Alan; Vigliola, Laurent; Bellwood, David R</p> <p>2014-09-23</p> <p>When <span class="hlt">tropical</span> systems lose species, they are often assumed to be buffered against declines in functional diversity by the ability of the species-rich biota to display high functional redundancy: i.e., a high number of species performing similar functions. We tested this hypothesis using a ninefold richness gradient in global fish faunas on <span class="hlt">tropical</span> reefs encompassing 6,316 species distributed among 646 functional entities (FEs): i.e., unique combinations of functional traits. We found that the highest functional redundancy is located in the <span class="hlt">Central</span> Indo-<span class="hlt">Pacific</span> with a mean of 7.9 species per FE. However, this overall level of redundancy is disproportionately packed into few FEs, a pattern termed functional over-redundancy (FOR). For instance, the most speciose FE in the <span class="hlt">Central</span> Indo-<span class="hlt">Pacific</span> contains 222 species (out of 3,689) whereas 38% of FEs (180 out of 468) have no functional insurance with only one species. Surprisingly, the level of FOR is consistent across the six fish faunas, meaning that, whatever the richness, over a third of the species may still be in overrepresented FEs whereas more than one third of the FEs are left without insurance, these levels all being significantly higher than expected by chance. Thus, our study shows that, even in high-diversity systems, such as <span class="hlt">tropical</span> reefs, functional diversity remains highly vulnerable to species loss. Although further investigations are needed to specifically address the influence of redundant vs. vulnerable FEs on ecosystem functioning, our results suggest that the promised benefits from <span class="hlt">tropical</span> biodiversity may not be as strong as previously thought.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4183327','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4183327"><span>Functional over-redundancy and high functional vulnerability in global fish faunas on <span class="hlt">tropical</span> reefs</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Mouillot, David; Villéger, Sébastien; Parravicini, Valeriano; Kulbicki, Michel; Arias-González, Jesus Ernesto; Bender, Mariana; Chabanet, Pascale; Floeter, Sergio R.; Friedlander, Alan; Vigliola, Laurent; Bellwood, David R.</p> <p>2014-01-01</p> <p>When <span class="hlt">tropical</span> systems lose species, they are often assumed to be buffered against declines in functional diversity by the ability of the species-rich biota to display high functional redundancy: i.e., a high number of species performing similar functions. We tested this hypothesis using a ninefold richness gradient in global fish faunas on <span class="hlt">tropical</span> reefs encompassing 6,316 species distributed among 646 functional entities (FEs): i.e., unique combinations of functional traits. We found that the highest functional redundancy is located in the <span class="hlt">Central</span> Indo-<span class="hlt">Pacific</span> with a mean of 7.9 species per FE. However, this overall level of redundancy is disproportionately packed into few FEs, a pattern termed functional over-redundancy (FOR). For instance, the most speciose FE in the <span class="hlt">Central</span> Indo-<span class="hlt">Pacific</span> contains 222 species (out of 3,689) whereas 38% of FEs (180 out of 468) have no functional insurance with only one species. Surprisingly, the level of FOR is consistent across the six fish faunas, meaning that, whatever the richness, over a third of the species may still be in overrepresented FEs whereas more than one third of the FEs are left without insurance, these levels all being significantly higher than expected by chance. Thus, our study shows that, even in high-diversity systems, such as <span class="hlt">tropical</span> reefs, functional diversity remains highly vulnerable to species loss. Although further investigations are needed to specifically address the influence of redundant vs. vulnerable FEs on ecosystem functioning, our results suggest that the promised benefits from <span class="hlt">tropical</span> biodiversity may not be as strong as previously thought. PMID:25225388</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20000027563&hterms=Environmental+Chemistry&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DEnvironmental%2BChemistry','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20000027563&hterms=Environmental+Chemistry&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DEnvironmental%2BChemistry"><span>Dependence of Cumulus Anvil Radiative Properties on Environmental Conditions in the <span class="hlt">Tropical</span> West <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ye, B.; DelGenio, A. D.</p> <p>1999-01-01</p> <p>Areally extensive, optically thick anvil clouds associated with mesoscale convective clusters dominate the shortwave cloud forcing in the <span class="hlt">tropics</span> and provide longwave forcing comparable to that of thin cirrus. Changes in the cover and optical thickness of <span class="hlt">tropical</span> anvils as climate warms can regulate the sign of cloud feedback. As a prelude to the study of MMCR data from the ARM TWP sites, we analyze ISCCP-derived radiative characteristics of anvils observed in the <span class="hlt">tropical</span> west <span class="hlt">Pacific</span> during the TOGA-COARE IOP. Anvils with radius greater than 100 km were identified and tracked from inception to decay using the Machado-Rossow algorithm. Corresponding environmental conditions just prior to the start of the convectove event were diagnosed using the Lin-Johnson objective analysis product. Small clusters (100-200 km radius) are observed to have a broad range of optical thicknesses (10-50), while intermediate optical thickness clusters are observed to range in size from 100 km to almost 1000 km. Large-size clusters appear to be favored by strong pre-storm large scale upward motion throughout the troposphere, moist low-to-midlevel relative humidities, environments with slightly higher CAPE than those for smaller clusters, and strong front-to-rear flow. Optically thick anvils are favored in situations of strong low-level moisture convergence and strong upper-level shear.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ThApC.tmp..180A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ThApC.tmp..180A"><span>Unstable relationships between tree ring δ18O and climate variables over southwestern China: possible impacts from increasing <span class="hlt">central</span> <span class="hlt">Pacific</span> SSTs</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>An, Wenling; Liu, Xiaohong; Hou, Shugui; Zeng, Xiaomin; Sun, Weizhen; Wang, Wenzhi; Wang, Yu; Xu, Guobao; Ren, Jiawen</p> <p>2018-05-01</p> <p>In this study, we investigated the potential influence of <span class="hlt">central</span> and eastern <span class="hlt">Pacific</span> sea surface temperatures (SSTs) on the unstable relationship between earlywood δ18O and climatic factors in the southwestern China from 1902 to 2005. The results show that the strength of the climate signals recorded in the earlywood δ18O series has declined since the late 1970s. This reduction in signal strength may have been caused by the changes in the local hydroclimate, which is associated with the increasing SSTs in the <span class="hlt">central</span> <span class="hlt">Pacific</span> Ocean over recent decades. Alongside these increasing SSTs in the <span class="hlt">central</span> <span class="hlt">Pacific</span>, southwestern China has experienced more droughts, as well as more severe droughts through the late spring and early summer during the <span class="hlt">central</span> <span class="hlt">Pacific</span> (CP) El Niño years than during the eastern <span class="hlt">Pacific</span> (EP) El Niño years in recent decades. This increased drought frequency may have weakened the response of earlywood δ18O to climate variables.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/6585348-southern-oscillation-surface-circulation-climate-over-tropical-atlantic-eastern-pacific-indian-oceans-captured-cluster-analysis','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/6585348-southern-oscillation-surface-circulation-climate-over-tropical-atlantic-eastern-pacific-indian-oceans-captured-cluster-analysis"><span>Southern Oscillation in surface circulation and climate over the <span class="hlt">tropical</span> Atlantic, eastern <span class="hlt">Pacific</span>, and Indian Oceans as captured by cluster analysis</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Wolter, K.</p> <p></p> <p>Clusters of sea level pressure (SLP), surface wind, cloudiness, and sea surface temperature (SST) in the domain of the <span class="hlt">tropical</span> Atlantic, eastern <span class="hlt">Pacific</span>, and Indian Oceans are introduced and discussed in terms of general circulation and climate. They appear to capture well the large-scale degrees of freedom of the seasonal fields. In the Atlantic, and, to a lesser extent, in the eastern <span class="hlt">Pacific</span>, most analyzed fields group into zonally oriented trade wind clusters. These are separated distinctly by the near-equatorial trough axis. By contrast, the Indian Ocean features strong interhemispheric connections associations with the monsoon systems of boreal summer and,more » to a lesser degree, of boreal winter. The usefulness of clusters thus established is elucidated with respect to the Southern Oscillation (SO). General circulation changes associated with this planetary pressure seesaw are deduced from the correlation maps of surface field clusters for January/February and July/August. During the positive SO phase (i.e., anomalously high pressure over the eastern <span class="hlt">Pacific</span> and anomalously low pressure over Indonesia), both the Atlantic and eastern <span class="hlt">Pacific</span> near-equatorial troughs are inferred to be shifted towards the north from July/August SLP, wind, and cloudiness fields. While eastern <span class="hlt">Pacific</span> trade winds are weakened in both seasons in the positive PO phase, the Atlantic trades appear strengthened at the same time in the winter hemisphere only. Over the Indian Ocean, the monsoon circulation seems to be strengthened during the positive SO phase, with the summer monsoon displaying a more complex picture. Its SLP, cloudiness, and SST fields support an enhanced southwest monsoon, while its surface winds appear largely inconclusive. SST is lowered during the positive SO phase in all three <span class="hlt">tropical</span> oceans.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19800031585&hterms=Lamontagne&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DLamontagne','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19800031585&hterms=Lamontagne&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DLamontagne"><span>Trace gas concentrations, intertropical convergence, atmospheric fronts, and ocean currents in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wilkniss, P. E.; Rodgers, E. B.; Swinnerton, J. W.; Larson, R. E.; Lamontagne, R. A.</p> <p>1979-01-01</p> <p>Descriptions of the intertropical convergence zones (ITCZ) in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> have been obtained from shipboard measurements of Rn-222, CO, and CH4 in combination with conventional meteorological data and satellite images. The intertropical convergence zone is marked by light shifting waves near an area of heavy cloud cover and precipitation, and appears to be located north and south of the south equatorial current. A 'second' ITCZ with the same atmospheric features was encountered just north of the south equatorial current in the Southern Hemisphere. Atmospheric Rn-222 increases north of the ITCZ and serves as a sensitive indicator for this atmospheric boundary.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001ClDy...17..205P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001ClDy...17..205P"><span>The relative importance of ENSO and <span class="hlt">tropical</span> Atlantic sea surface temperature anomalies for seasonal precipitation over South America: a numerical study</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pezzi, L. P.; Cavalcanti, I. F. A.</p> <p></p> <p>The role of <span class="hlt">tropical</span> Atlantic sea surface temperature (SST) anomalies during ENSO episodes over northeast Brazil (Nordeste) is investigated using the CPTEC/COLA Atmospheric General Circulation Model (AGCM). Four sets of integrations are performed using SST in El Niño and La Niña (ENSO) episodes, changing the SST of the Atlantic Ocean. A positive dipole (SST higher than normal in the <span class="hlt">tropical</span> North Atlantic and below normal in the <span class="hlt">tropical</span> South Atlantic) and a negative dipole (opposite conditions), are set as the boundary conditions of SST in the Atlantic Ocean. The four experiments are performed using El Niño or La Niña SST in all oceans, except in the <span class="hlt">tropical</span> Atlantic where the two phases of the SST dipole are applied. Five initial conditions were integrated in each case in order to obtain four ensemble results. The positive SST dipole over the <span class="hlt">tropical</span> Atlantic Ocean and El Niño conditions over the <span class="hlt">Pacific</span> Ocean resulted in dry conditions over the Nordeste. When the negative dipole and El Niño conditions over the <span class="hlt">Pacific</span> Ocean were applied, the results showed precipitation above normal over the north of Nordeste. When La Niña conditions over <span class="hlt">Pacific</span> Ocean were tested together with a negative dipole, positive precipitation anomalies occurred over the whole Nordeste. Using the positive dipole over the <span class="hlt">tropical</span> Atlantic, the precipitation over Nordeste was below average. During La Niña episodes, the Atlantic Ocean conditions have a larger effect on the precipitation of Nordeste than the <span class="hlt">Pacific</span> Ocean. In El Niño conditions, only the north region of Nordeste is affected by the Atlantic SST. Other <span class="hlt">tropical</span> areas of South America show a change only in the intensity of anomalies. <span class="hlt">Central</span> and southeast regions of South America are affected by the Atlantic conditions only during La Niña conditions, whereas during El Niño these regions are influenced only by conditions in the <span class="hlt">Pacific</span> Ocean.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24403331','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24403331"><span>Predicting bycatch hotspots for endangered leatherback turtles on longlines in the <span class="hlt">Pacific</span> Ocean.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Roe, John H; Morreale, Stephen J; Paladino, Frank V; Shillinger, George L; Benson, Scott R; Eckert, Scott A; Bailey, Helen; Tomillo, Pilar Santidrián; Bograd, Steven J; Eguchi, Tomoharu; Dutton, Peter H; Seminoff, Jeffrey A; Block, Barbara A; Spotila, James R</p> <p>2014-02-22</p> <p>Fisheries bycatch is a critical source of mortality for rapidly declining populations of leatherback turtles, Dermochelys coriacea. We integrated use-intensity distributions for 135 satellite-tracked adult turtles with longline fishing effort to estimate predicted bycatch risk over space and time in the <span class="hlt">Pacific</span> Ocean. Areas of predicted bycatch risk did not overlap for eastern and western <span class="hlt">Pacific</span> nesting populations, warranting their consideration as distinct management units with respect to fisheries bycatch. For western <span class="hlt">Pacific</span> nesting populations, we identified several areas of high risk in the north and <span class="hlt">central</span> <span class="hlt">Pacific</span>, but greatest risk was adjacent to primary nesting beaches in <span class="hlt">tropical</span> seas of Indo-<span class="hlt">Pacific</span> islands, largely confined to several exclusive economic zones under the jurisdiction of national authorities. For eastern <span class="hlt">Pacific</span> nesting populations, we identified moderate risk associated with migrations to nesting beaches, but the greatest risk was in the South <span class="hlt">Pacific</span> Gyre, a broad pelagic zone outside national waters where management is currently lacking and may prove difficult to implement. Efforts should focus on these predicted hotspots to develop more targeted management approaches to alleviate leatherback bycatch.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3896015','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3896015"><span>Predicting bycatch hotspots for endangered leatherback turtles on longlines in the <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Roe, John H.; Morreale, Stephen J.; Paladino, Frank V.; Shillinger, George L.; Benson, Scott R.; Eckert, Scott A.; Bailey, Helen; Tomillo, Pilar Santidrián; Bograd, Steven J.; Eguchi, Tomoharu; Dutton, Peter H.; Seminoff, Jeffrey A.; Block, Barbara A.; Spotila, James R.</p> <p>2014-01-01</p> <p>Fisheries bycatch is a critical source of mortality for rapidly declining populations of leatherback turtles, Dermochelys coriacea. We integrated use-intensity distributions for 135 satellite-tracked adult turtles with longline fishing effort to estimate predicted bycatch risk over space and time in the <span class="hlt">Pacific</span> Ocean. Areas of predicted bycatch risk did not overlap for eastern and western <span class="hlt">Pacific</span> nesting populations, warranting their consideration as distinct management units with respect to fisheries bycatch. For western <span class="hlt">Pacific</span> nesting populations, we identified several areas of high risk in the north and <span class="hlt">central</span> <span class="hlt">Pacific</span>, but greatest risk was adjacent to primary nesting beaches in <span class="hlt">tropical</span> seas of Indo-<span class="hlt">Pacific</span> islands, largely confined to several exclusive economic zones under the jurisdiction of national authorities. For eastern <span class="hlt">Pacific</span> nesting populations, we identified moderate risk associated with migrations to nesting beaches, but the greatest risk was in the South <span class="hlt">Pacific</span> Gyre, a broad pelagic zone outside national waters where management is currently lacking and may prove difficult to implement. Efforts should focus on these predicted hotspots to develop more targeted management approaches to alleviate leatherback bycatch. PMID:24403331</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=S72-36293&hterms=need+touch&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dneed%2Btouch','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=S72-36293&hterms=need+touch&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dneed%2Btouch"><span>Apollo 16 spacecraft touches down in the <span class="hlt">central</span> <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1972-01-01</p> <p>The Apollo 16 spacecraft touches down in the <span class="hlt">central</span> <span class="hlt">Pacific</span> Ocean at the end of its mission. Splashdown occured at 1:45:06 p.m., Thursday, April 27, 1972, at coordinates of 00:45.2 degrees south latitude and 156:11.4 degrees west longitude, a point approximately 215 miles southeast of Christmas Island. All its parachutes are fully deployed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ClDy...47.2601K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ClDy...47.2601K"><span>The tropospheric biennial oscillation defined by a biennial mode of sea surface temperature and its impact on the atmospheric circulation and precipitation in the <span class="hlt">tropical</span> eastern Indo-western <span class="hlt">Pacific</span> region</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kim, Jinju; Kim, Kwang-Yul</p> <p>2016-10-01</p> <p>Temporal and spatial patterns of anomalous atmospheric circulation and precipitation over the Indo-<span class="hlt">Pacific</span> region are analyzed in conjunction with the Tropospheric Biennial Oscillation as represented by the biennial mode of sea surface temperature anomalies (SSTA). The biennial components of key variables are identified independently of other variability via CSEOF analysis. Then, its impact on the Asian-Australian monsoon is examined. The biennial mode exhibits a seasonally distinctive atmospheric response over the <span class="hlt">tropical</span> eastern Indo-western <span class="hlt">Pacific</span> (EIWP) region (90°-150°E, 20°S-20°N). In boreal summer, local meridional circulation is a distinguishing characteristic over the <span class="hlt">tropical</span> EIWP region, whereas a meridionally expanded branch of intensified zonal circulation develops in austral summer. Temporally varying evolution and distinct timing of SSTA phase transition in the Indian and <span class="hlt">Pacific</span> Oceans is considered a main factor for this variation of circulation in the <span class="hlt">tropical</span> EIWP region. The impact of the biennial mode is not the same between the two seasons, with different impacts over ocean areas in Asian monsoon and Australian monsoon regions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.loc.gov/pictures/collection/hh/item/nv0233.photos.375095p/','SCIGOV-HHH'); return false;" href="https://www.loc.gov/pictures/collection/hh/item/nv0233.photos.375095p/"><span>5. Plat of Carlin Shops, 1884. Copied from <span class="hlt">Central</span> <span class="hlt">Pacific</span> ...</span></a></p> <p><a target="_blank" href="http://www.loc.gov/pictures/collection/hh/">Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey</a></p> <p></p> <p></p> <p>5. Plat of Carlin Shops, 1884. Copied from <span class="hlt">Central</span> <span class="hlt">Pacific</span> Railroad bound book of station plats entitled 'Station Plans, CPRR, Mill City to Ogden,' in collection of Nevada Historical Society, Reno; credit Nevada Historical Society. Caption reads, 'Sand House - Hose Carriage Ho. - Casting Shed - Tank 'h' - Coal Shed 'I' and Iron Rack - finished in Oct. 1882. Tank 'c' built Nov. 1883 - Old Tank opp. & near main track taken down Nov. '83. E.C. Pierce's boarding house built May 1884. 172' old 1' pipe laid to Boarding house May 1884. 142 ft. 1' gas pipe - 2 Globe Valves laid to Div. Sup'ts Office Sept 1884.' Engine Stores Building is shown as building k. - Southern <span class="hlt">Pacific</span> Railroad, Carlin Shops, Foot of Sixth Street, Carlin, Elko County, NV</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3546052','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3546052"><span>A comparative study of Taiwan's short-term medical missions to the South <span class="hlt">Pacific</span> and <span class="hlt">Central</span> America</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p></p> <p>2012-01-01</p> <p>Background Taiwan has been dispatching an increasing number of short-term medical missions (STMMs) to its allied nations to provide humanitarian health care; however, overall evaluations to help policy makers strengthen the impact of such missions are lacking. Our primary objective is to identify useful strategies by comparing STMMs to the South <span class="hlt">Pacific</span> and <span class="hlt">Central</span> America. Methods The data for the evaluation come from two main sources: the official reports of 46 missions to 11 countries in <span class="hlt">Central</span> America and 25 missions to 8 countries in the South <span class="hlt">Pacific</span>, and questionnaires completed by health professionals who had participated in the above missions. In <span class="hlt">Central</span> America, STMMs were staffed by volunteer health professionals from multiple institutions. In the South <span class="hlt">Pacific</span>, STMMs were staffed by volunteer health professionals from single institutions. Results In comparison to STMMs to <span class="hlt">Central</span> America, STMMs to the South <span class="hlt">Pacific</span> accomplished more educational training for local health providers, including providing heath-care knowledge and skills (p<0.05), and training in equipment administration (p<0.001) and drug administration (p<0.005). In addition, language constraints were more common among missions to <span class="hlt">Central</span> America (p<0.001). There was no significant difference in the performance of clinical service between the two regions. Conclusions Health-care services provided by personnel from multiple institutions are as efficient as those from single institutions. Proficiency in the native language and provision of education for local health-care workers are essential for conducting a successful STMM. Our data provide implications for integrating evidence into the deployment of STMMs. PMID:23270459</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110007278','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110007278"><span>Electrically-Active Convection and <span class="hlt">Tropical</span> Cyclogenesis in the Atlantic and East <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Leppert, Kenneth D., II; Petersen, Walter A.</p> <p>2010-01-01</p> <p>It has been hypothesized that deep, intense convective-scale "hot" towers may aid the process of <span class="hlt">tropical</span> cyclogenesis and intensification through dynamic and thermodynamic feedbacks on the larger meso-to-synoptic scale circulation. In this study, we make use of NCEP Reanalysis data and <span class="hlt">Tropical</span> Rainfall Measurement Mission (TRMM) lightning imaging sensor (LIS), precipitation radar (PR), and microwave imager (TMI) data to investigate the role that widespread and/or intense lightning-producing convection (i.e., "electrically-hot towers") present in African easterly waves (AEWs) may play in <span class="hlt">tropical</span> cyclogenesis over the Atlantic, Caribbean, and East <span class="hlt">Pacific</span> regions. NCEP Reanalysis 700 hPa meridional winds for the months of June to November for the years 2001-2009 were analyzed for the domain of 5degN-20degN and 130degW-20degE in order to partition individual AEWs into northerly, southerly, trough, and ridge phases. Subsequently, information from National Hurricane Center (NHC) storm reports was used to divide the waves into developing and non-developing waves and to further divide the developing waves into those waves that spawned storms that only developed to <span class="hlt">tropical</span> storm strength and those that spawned storms that reached hurricane strength. The developing waves were also divided by the region in which they developed. To help determine the gross nature of the smaller convective scale, composites were created of all developing and non-developing waves as a function of AEW wave phase over the full analysis domain and over various smaller longitude bands by compositing TRMM PR, TMI, LIS, and IR brightness temperature data extracted from the NASA global-merged IR brightness temperature dataset. Finally, similar composites were created using various NCEP variables to assess the nature of the larger scale environment and circulation. Results suggest a clear distinction between developing and non-developing waves as developing waves near their region of development in</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUFM.U22B..02L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUFM.U22B..02L"><span><span class="hlt">Central</span> American rainfall variations since 100 ka and moisture delivery to Greenland</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lachniet, M. S.; Asmerom, Y.; Johnson, L.; Burns, S.; Polyak, V.; Patterson, W.</p> <p>2007-12-01</p> <p>We present a rainfall history for <span class="hlt">Central</span> America based on oxygen isotope values in Uranium-series dated stalagmites collected from the <span class="hlt">Pacific</span> Coast of Costa Rica over parts of the Holocene and from 25 to 100 ka. The oxygen isotope values of modern rainfall in our study area within the heart of the Intertropical Convergence Zone (ITCZ) are dominated by the amount effect and moisture source, and we interpret our data as a paleorainfall proxy. Our data show substantial oxygen isotope variability on centennial to multi-millennial time scales. Further, our paleorainfall time series is strongly correlated with the deuterium excess parameter in Greenland Ice, which suggests that the strength of the <span class="hlt">tropical</span> hydrological cycle has modulated the flow of low-latitude moisture to Greenland on millennial time scales. Our results indicate a strong coupling between <span class="hlt">tropical</span> and high latitude paleoclimate, that was likely linked via variations in the strength of the Hadley cell and its associated export of atmospheric moisture to the high latitudes. We observe the wettest periods in <span class="hlt">Central</span> America when the Caribbean was warmer than 26.5 degrees C and the Caribbean to <span class="hlt">Pacific</span> (cold tongue) SST gradient was largest, suggesting a combined Atlantic and <span class="hlt">Pacific</span> Ocean control on ITCZ rainfall.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25540693','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25540693"><span>Population structure and phylogeography reveal pathways of colonization by a migratory marine reptile (Chelonia mydas) in the <span class="hlt">central</span> and eastern <span class="hlt">Pacific</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Dutton, Peter H; Jensen, Michael P; Frey, Amy; LaCasella, Erin; Balazs, George H; Zárate, Patricia; Chassin-Noria, Omar; Sarti-Martinez, Adriana Laura; Velez, Elizabeth</p> <p>2014-11-01</p> <p>Climate, behavior, ecology, and oceanography shape patterns of biodiversity in marine faunas in the absence of obvious geographic barriers. Marine turtles are an example of highly migratory creatures with deep evolutionary lineages and complex life histories that span both terrestrial and marine environments. Previous studies have focused on the deep isolation of evolutionary lineages (>3 mya) through vicariance; however, little attention has been given to the pathways of colonization of the eastern <span class="hlt">Pacific</span> and the processes that have shaped diversity within the most recent evolutionary time. We sequenced 770 bp of the mtDNA control region to examine the stock structure and phylogeography of 545 green turtles from eight different rookeries in the <span class="hlt">central</span> and eastern <span class="hlt">Pacific</span>. We found significant differentiation between the geographically separated nesting populations and identified five distinct stocks (F ST = 0.08-0.44, P < 0.005). <span class="hlt">Central</span> and eastern <span class="hlt">Pacific</span> Chelonia mydas form a monophyletic group containing 3 subclades, with Hawaii more closely related to the eastern <span class="hlt">Pacific</span> than western <span class="hlt">Pacific</span> populations. The split between sampled <span class="hlt">central</span>/eastern and western <span class="hlt">Pacific</span> haplotypes was estimated at around 0.34 mya, suggesting that the <span class="hlt">Pacific</span> region west of Hawaii has been a more formidable barrier to gene flow in C. mydas than the East <span class="hlt">Pacific</span> Barrier. Our results suggest that the eastern <span class="hlt">Pacific</span> was colonized from the western <span class="hlt">Pacific</span> via the <span class="hlt">Central</span> North <span class="hlt">Pacific</span> and that the Revillagigedos Islands provided a stepping-stone for radiation of green turtles from the Hawaiian Archipelago to the eastern <span class="hlt">Pacific</span>. Our results fit with a broader paradigm that has been described for marine biodiversity, where oceanic islands, such as Hawaii and Revillagigedo, rather than being peripheral evolutionary "graveyards", serve as sources and recipients of diversity and provide a mechanism for further radiation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4267870','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4267870"><span>Population structure and phylogeography reveal pathways of colonization by a migratory marine reptile (Chelonia mydas) in the <span class="hlt">central</span> and eastern <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Dutton, Peter H; Jensen, Michael P; Frey, Amy; LaCasella, Erin; Balazs, George H; Zárate, Patricia; Chassin-Noria, Omar; Sarti-Martinez, Adriana Laura; Velez, Elizabeth</p> <p>2014-01-01</p> <p>Climate, behavior, ecology, and oceanography shape patterns of biodiversity in marine faunas in the absence of obvious geographic barriers. Marine turtles are an example of highly migratory creatures with deep evolutionary lineages and complex life histories that span both terrestrial and marine environments. Previous studies have focused on the deep isolation of evolutionary lineages (>3 mya) through vicariance; however, little attention has been given to the pathways of colonization of the eastern <span class="hlt">Pacific</span> and the processes that have shaped diversity within the most recent evolutionary time. We sequenced 770 bp of the mtDNA control region to examine the stock structure and phylogeography of 545 green turtles from eight different rookeries in the <span class="hlt">central</span> and eastern <span class="hlt">Pacific</span>. We found significant differentiation between the geographically separated nesting populations and identified five distinct stocks (FST = 0.08–0.44, P < 0.005). <span class="hlt">Central</span> and eastern <span class="hlt">Pacific</span> Chelonia mydas form a monophyletic group containing 3 subclades, with Hawaii more closely related to the eastern <span class="hlt">Pacific</span> than western <span class="hlt">Pacific</span> populations. The split between sampled <span class="hlt">central</span>/eastern and western <span class="hlt">Pacific</span> haplotypes was estimated at around 0.34 mya, suggesting that the <span class="hlt">Pacific</span> region west of Hawaii has been a more formidable barrier to gene flow in C. mydas than the East <span class="hlt">Pacific</span> Barrier. Our results suggest that the eastern <span class="hlt">Pacific</span> was colonized from the western <span class="hlt">Pacific</span> via the <span class="hlt">Central</span> North <span class="hlt">Pacific</span> and that the Revillagigedos Islands provided a stepping-stone for radiation of green turtles from the Hawaiian Archipelago to the eastern <span class="hlt">Pacific</span>. Our results fit with a broader paradigm that has been described for marine biodiversity, where oceanic islands, such as Hawaii and Revillagigedo, rather than being peripheral evolutionary “graveyards”, serve as sources and recipients of diversity and provide a mechanism for further radiation. PMID:25540693</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950048105&hterms=orbiting+wind&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dorbiting%2Bwind','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950048105&hterms=orbiting+wind&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dorbiting%2Bwind"><span>One- to two-month oscillations in SSMI surface wind speed in western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Collins, Michael L.; Stanford, John L.; Halpern, David</p> <p>1994-01-01</p> <p>The 10-m wind speed over the ocean can be estimated from microwave brightness temperature measurements recorded by the Special Sensor Microwave Imager (SSMI) instrument mounted on a polar-orbiting spacecraft. Four-year (1988-1991) time series of average daily 1 deg x 1 deg SSMI wind speeds were analyzed at selected sites in the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean. One- to two-month period wind speed oscillations with amplitudes statistically significant at the 95% confidence level were observed near Kanton, Eniwetok, Guam, and Truk. This is the first report of such an oscillation in SSMI wind speeds.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMPP43A2293Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMPP43A2293Y"><span>Cenozoic dynamics of shallow-marine biodiversity in the Western <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yasuhara, M.; Iwatani, H.; Hunt, G.; Okahashi, H.; Kase, T.; Hayashi, H.; Irizuki, T.; Aguilar, Y. M.; Fernando, A. G. S.; Renema, W.</p> <p>2016-12-01</p> <p>Cenozoic dynamics of large-scale species diversity patterns remain poorly understood, especially for the Western <span class="hlt">Pacific</span>, in part because of the paucity of well-dated fossil records from the <span class="hlt">tropics</span>. Here we show the spatiotemporal dynamics of species diversity in the Western <span class="hlt">Pacific</span> through the Cenozoic, focusing on the <span class="hlt">tropical</span> Indo-Australian Archipelago (IAA) biodiversity hotspot. We analysed well-preserved fossil ostracodes from the <span class="hlt">tropical</span> Western <span class="hlt">Pacific</span> and combined their diversity data with other published data from the region to reconstruct Cenozoic dynamics of species diversity in the <span class="hlt">tropical</span>- and northwestern <span class="hlt">Pacific</span> Ocean. We fit generalized additive models to test for differences in richness over time and across geographic regions while accounting for sample size variation among samples. Low-, mid- and high-latitude regions all show a similar diversity trajectory: diversity is low in the Eocene and Oligocene, increases from the Early Miocene to the Plio-Pleistocene but then declines to the present day. Present day high biodiversity in these regions was established during the Pliocene with a remarkable diversification at that time. Latitudinal diversity patterns are relatively flat and never show as simple decline from the <span class="hlt">tropics</span> to higher latitudes. Western <span class="hlt">Pacific</span> Cenozoic ostracodes exhibit a spatiotemporal pattern of species diversity that is inconsistent with the commonly reported and persistent pattern of declining diversity from the <span class="hlt">tropics</span> to the extratropics. While this inconsistency could be interpreted as evidence that ostracodes are a contrarian clade, Atlantic ostracodes display a standard latitudinal species diversity gradient. Contrasting patterns between oceans suggests an important role for regional factors (e.g., plate tectonics and temporal geomorphological dynamics) in shaping the biodiversity of the Western <span class="hlt">Pacific</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000JCli...13.2177S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000JCli...13.2177S"><span>Interaction between <span class="hlt">Tropical</span> Atlantic Variability and El Niño-Southern Oscillation.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Saravanan, R.; Chang, Ping</p> <p>2000-07-01</p> <p>The interaction between <span class="hlt">tropical</span> Atlantic variability and El Niño-Southern Oscillation (ENSO) is investigated using three ensembles of atmospheric general circulation model integrations. The integrations are forced by specifying observed sea surface temperature (SST) variability over a forcing domain. The forcing domain is the global ocean for the first ensemble, limited to the <span class="hlt">tropical</span> ocean for the second ensemble, and further limited to the <span class="hlt">tropical</span> Atlantic region for the third ensemble. The ensemble integrations show that extratropical SST anomalies have little impact on <span class="hlt">tropical</span> variability, but the effect of ENSO is pervasive in the <span class="hlt">Tropics</span>. Consistent with previous studies, the most significant influence of ENSO is found during the boreal spring season and is associated with an anomalous Walker circulation. Two important aspects of ENSO's influence on <span class="hlt">tropical</span> Atlantic variability are noted. First, the ENSO signal contributes significantly to the `dipole' correlation structure between <span class="hlt">tropical</span> Atlantic SST and rainfall in the Nordeste Brazil region. In the absence of the ENSO signal, the correlations are dominated by SST variability in the southern <span class="hlt">tropical</span> Atlantic, resulting in less of a dipole structure. Second, the remote influence of ENSO also contributes to positive correlations between SST anomalies and downward surface heat flux in the <span class="hlt">tropical</span> Atlantic during the boreal spring season. However, even when ENSO forcing is absent, the model integrations provide evidence for a positive surface heat flux feedback in the deep <span class="hlt">Tropics</span>, which is analyzed in a companion study by Chang et al. The analysis of model simulations shows that interannual atmospheric variability in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>-Atlantic system is dominated by the interaction between two distinct sources of <span class="hlt">tropical</span> heating: (i) an equatorial heat source in the eastern <span class="hlt">Pacific</span> associated with ENSO and (ii) an off-equatorial heat source associated with SST anomalies near the Caribbean</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMPP41C2267S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMPP41C2267S"><span>North <span class="hlt">Pacific</span> Meridional Mode over the Common Era</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sanchez, S. C.; Charles, C. D.; Amaya, D. J.; Miller, A. J.</p> <p>2016-12-01</p> <p>The <span class="hlt">Pacific</span> Meridional Mode (PMM) has been increasingly recognized as an influential mode of variability for channeling extratropical anomalies to the equatorial ocean-atmosphere system. The PMM has been identified as an important precursor for ENSO, a source of much decadal power in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, and is potentially intensifying. It is still unknown why the <span class="hlt">Pacific</span> Meridional Mode might be intensifying; most arguments center around the changing mean state associated with anthropogenic global warming. There are a number of processes by which the background state could influence the PMM: altering the location of trade winds, the characteristics of stochastic forcing, the sensitivity of latent heat flux to surface wind anomalies, the wind response to SST anomalies, or changing the Intertropical Convergence Zone (ITCZ) structure. Recent work has found that the PMM is particularly sensitive to ITCZ shifts in intensity and location (using a simple linear coupled model, [Martinez-Villalobos and Vimont 2016]). Over the last millennium the ITCZ has experienced epochs of notable latitudinal shifts to balance the cross equatorial energy transport. Here we investigate how the strength of the PMM may have varied with these shifts in the ITCZ over the Common Era using the CESM-Last Millennium Ensemble (LME). We assess the strength of the PMM pathway by the degree of air-sea coupling and the amplitude of <span class="hlt">tropical</span> decadal variability. We expect the ITCZ location and the degree of air-sea coupling (WES feedback) to play a critical role in determining the effectiveness and intensity of the PMM pathway. We verify our inferences in the LME with coral paleoproxy records from the <span class="hlt">central</span> <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. Chiefly we target records from the Line Islands (spanning 1°N to 6°N) to infer variations in the location of the ITCZ and the amplitude of decadal variability. This work enables us to discuss the idea of an intensifying PMM in a more historical context.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018NatCC...8...64H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018NatCC...8...64H"><span>Inverse relationship between present-day <span class="hlt">tropical</span> precipitation and its sensitivity to greenhouse warming</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ham, Yoo-Geun; Kug, Jong-Seong; Choi, Jun-Young; Jin, Fei-Fei; Watanabe, Masahiro</p> <p>2018-01-01</p> <p>Future changes in rainfall have serious impacts on human adaptation to climate change, but quantification of these changes is subject to large uncertainties in climate model projections. To narrow these uncertainties, significant efforts have been made to understand the intermodel differences in future rainfall changes. Here, we show a strong inverse relationship between present-day precipitation and its future change to possibly calibrate future precipitation change by removing the present-day bias in climate models. The results of the models with less <span class="hlt">tropical</span> (40° S-40° N) present-day precipitation are closely linked to the dryness over the equatorial <span class="hlt">central</span>-eastern <span class="hlt">Pacific</span>, and project weaker regional precipitation increase due to the anthropogenic greenhouse forcing1-6 with stronger zonal Walker circulation. This induces Indo-western <span class="hlt">Pacific</span> warming through Bjerknes feedback, which reduces relative humidity by the enhanced atmospheric boundary-layer mixing in the future projection. This increases the air-sea humidity difference to enhance <span class="hlt">tropical</span> evaporation and the resultant precipitation. Our estimation of the sensitivity of the <span class="hlt">tropical</span> precipitation per 1 K warming, after removing a common bias in the present-day simulation, is about 50% greater than the original future multi-model projection.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017GBioC..31.1470Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017GBioC..31.1470Y"><span>ENSO-Driven Variability of Denitrification and Suboxia in the Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yang, Simon; Gruber, Nicolas; Long, Matthew C.; Vogt, Meike</p> <p>2017-10-01</p> <p>The Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> (ETP) hosts two of the world's three Oxygen Deficient Zones (ODZs), large bodies of suboxic water that are subject to high rates of water column denitrification (WCD). In the mean, these two ODZs are responsible for about 15 to 40% of all fixed N loss in the ocean, but little is known about how this loss varies in time. Here we use a hindcast simulation with the ocean component of the National Center for Atmospheric Research (NCAR) Community Earth System Model over the period 1948 to 2009 to show that the El Niño-Southern Oscillation (ENSO) drives large variations in the rates of WCD in this region. During mature La Niña (El Niño) conditions, peak denitrification rates are up to 70% higher (lower) than the mean rates. This large variability is the result of wind-driven changes in circulation and isopycnal structure concurrently modifying the thermocline distribution of O2 and organic matter export in such a way that the response of WCD is strongly amplified. During average La Niña (El Niño) conditions, the overall changes in ODZ structure and primarily the shoaling (deepening) of the upper boundary of both ODZs by 40 to 100 m explains 50% of the changes in WCD in the North <span class="hlt">Pacific</span> and 94% in the South <span class="hlt">Pacific</span>. Such a large variability of WCD in the ETP has strong implications for the assessments of trends, the balance of the marine N cycle and the emission of the greenhouse gas N2O.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=S72-36297&hterms=need+touch&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dneed%2Btouch','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=S72-36297&hterms=need+touch&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dneed%2Btouch"><span>Apollo 16 spacecraft touches down in the <span class="hlt">central</span> <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1972-01-01</p> <p>The Apollo 16 spacecraft touches down in the <span class="hlt">central</span> <span class="hlt">Pacific</span> Ocean at the end of its mission. Splashdown occurred at 1:45:06 p.m., Thursday, April 27, 1972 at coordinates of 00:45.2 degrees south latitude and 156:11.4 degrees west longitude, a point approximately 215 miles southeast of Christmas Island. All its parachutes are collapsing in the ocean around the Command Module.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004AGUFMPP23C..01M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004AGUFMPP23C..01M"><span>A Review of <span class="hlt">Pacific</span> Interdecadal Climate Variability: Possible Mechanisms and Surface Climate Signatures in the <span class="hlt">Pacific</span> Sector</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mantua, N. J.</p> <p>2004-12-01</p> <p>Many investigators have examined historical surface climate records from the <span class="hlt">Pacific</span> sector and identified a relatively small number of spatial patterns varying at decadal to interdecadal time scales. "<span class="hlt">Pacific</span> Decadal Variability" (PDV) is a label that has been used to describe this family of climate variations. Some patterns of PDV are contained completely within the northern extratropics, while others have signatures throughout the <span class="hlt">Pacific</span> hemisphere on both sides of the equator. Mechanisms for observed patterns of PDV are not yet known, though a wide variety of hypotheses have been proposed. Various ocean-atmosphere mechanisms for PDV are contained within the extratropics, others within the <span class="hlt">tropics</span>, while others involve <span class="hlt">tropical</span>-extratropical interactions. Some investigators have proposed external forcing (solar, lunar, or volcanic) as potentially important for driving PDV. A relatively simple hypothesis couples ENSO forcing with upper ocean heat storage for extratropical PDV, and it suggests PDV predictability may be limited to ~2 year lead times. Paleo-PDV reconstructions have been based on materials throughout the <span class="hlt">Pacific</span> sector using such things as extratropical tree-rings, <span class="hlt">tropical</span> corals, extratropical clam shell growth rings, and ice cores. These different proxy records have generally provided different perspectives on paleo-PDV behavior.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ams.confex.com/ams/93Annual/webprogram/Paper219818.html','USGSPUBS'); return false;" href="https://ams.confex.com/ams/93Annual/webprogram/Paper219818.html"><span>The anomalous circulation associated with the ENSO-related west <span class="hlt">Pacific</span> sea surface temperature gradient</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Hoell, Andrew; Funk, Christopher C.</p> <p>2013-01-01</p> <p>The temporal evolution and distribution of <span class="hlt">Pacific</span> SST as well as the near-surface <span class="hlt">tropical</span> <span class="hlt">Pacific</span> zonal wind, <span class="hlt">tropical</span> divergence and vertical velocity are considerably different during ENSO events partitioned according to the strength of the WPG. Modifications to the <span class="hlt">tropical</span> circulation result in changes to the Indo-west <span class="hlt">Pacific</span> precipitation and vertically integrated energy budgets and are linked to strong and consistent circulation and precipitation modifications throughout the Northern Hemisphere during winter.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/FR-2012-12-03/pdf/2012-29028.pdf','FEDREG'); return false;" href="https://www.gpo.gov/fdsys/pkg/FR-2012-12-03/pdf/2012-29028.pdf"><span>77 FR 71501 - International Fisheries; Western and <span class="hlt">Central</span> <span class="hlt">Pacific</span> Fisheries for Highly Migratory Species...</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR">Federal Register 2010, 2011, 2012, 2013, 2014</a></p> <p></p> <p>2012-12-03</p> <p>...NMFS issues regulations under the authority of the Western and <span class="hlt">Central</span> <span class="hlt">Pacific</span> Fisheries Convention Implementation Act (WCPFC Implementation Act) to implement requirements for U.S. fishing vessels used for commercial fishing that offload or receive transshipments of highly migratory species (HMS), U.S. fishing vessels used for commercial fishing that provide bunkering or other support services to fishing vessels, and U.S. fishing vessels used for commercial fishing that receive bunkering or engage in other support services, in the area of application of the Convention on the Conservation and Management of Highly Migratory Fish Stocks in the Western and <span class="hlt">Central</span> <span class="hlt">Pacific</span> Ocean (Convention). Some of the requirements also apply to transshipments of fish caught in the area of application of the Convention (Convention Area) and transshipped elsewhere. NMFS also issues requirements regarding notification of entry into and exit from the ``Eastern High Seas Special Management Area'' (Eastern SMA) and requirements relating to discards from purse seine fishing vessels. This action is necessary for the United States to implement decisions of the Commission for the Conservation and Management of Highly Migratory Fish Stocks in the Western and <span class="hlt">Central</span> <span class="hlt">Pacific</span> Ocean (Commission or WCPFC) and to satisfy its obligations under the Convention, to which it is a Contracting Party.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1617208','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1617208"><span>Marine lake ecosystem dynamics illustrate ENSO variation in the <span class="hlt">tropical</span> western <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Martin, Laura E; Dawson, Michael N; Bell, Lori J; Colin, Patrick L</p> <p>2005-01-01</p> <p>Understanding El Niño/Southern Oscillation (ENSO) and its biological consequences is hindered by a lack of high-resolution, long-term data from the <span class="hlt">tropical</span> western <span class="hlt">Pacific</span>. We describe a preliminary, 6 year dataset that shows tightly coupled ENSO-related bio-physical dynamics in a seawater lake in Palau, Micronesia. The lake is more strongly stratified during La Niña than El Niño conditions, temperature anomalies in the lake co-vary strongly with the Niño 3.4 climate index, and the abundance of the dominant member of the pelagic community, an endemic subspecies of zooxanthellate jellyfish, is temperature associated. These results have broad relevance because the lake: (i) illustrates an ENSO signal that is partly obscured in surrounding semi-enclosed lagoon waters and, therefore, (ii) may provide a model system for studying the effects of climate change on community evolution and cnidarian–zooxanthellae symbioses, which (iii) should be traceable throughout the Holocene because the lake harbours a high quality sediment record; the sediment record should (iv) provide a sensitive and regionally unique record of Holocene climate relevant to predicting ENSO responses to future global climate change and, finally, (v) seawater lake ecosystems elsewhere in the <span class="hlt">Pacific</span> may hold similar potential for past, present, and predictive measurements of climate variation and ecosystem response. PMID:17148349</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17148349','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17148349"><span>Marine lake ecosystem dynamics illustrate ENSO variation in the <span class="hlt">tropical</span> western <span class="hlt">Pacific</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Martin, Laura E; Dawson, Michael N; Bell, Lori J; Colin, Patrick L</p> <p>2006-03-22</p> <p>Understanding El Niño/Southern Oscillation (ENSO) and its biological consequences is hindered by a lack of high-resolution, long-term data from the <span class="hlt">tropical</span> western <span class="hlt">Pacific</span>. We describe a preliminary, 6 year dataset that shows tightly coupled ENSO-related bio-physical dynamics in a seawater lake in Palau, Micronesia. The lake is more strongly stratified during La Niña than El Niño conditions, temperature anomalies in the lake co-vary strongly with the Niño 3.4 climate index, and the abundance of the dominant member of the pelagic community, an endemic subspecies of zooxanthellate jellyfish, is temperature associated. These results have broad relevance because the lake: (i) illustrates an ENSO signal that is partly obscured in surrounding semi-enclosed lagoon waters and, therefore, (ii) may provide a model system for studying the effects of climate change on community evolution and cnidarian-zooxanthellae symbioses, which (iii) should be traceable throughout the Holocene because the lake harbours a high quality sediment record; the sediment record should (iv) provide a sensitive and regionally unique record of Holocene climate relevant to predicting ENSO responses to future global climate change and, finally, (v) seawater lake ecosystems elsewhere in the <span class="hlt">Pacific</span> may hold similar potential for past, present, and predictive measurements of climate variation and ecosystem response.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMGC41B1015W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMGC41B1015W"><span>Interannual to Decadal SST Variability in the <span class="hlt">Tropical</span> Indian Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, G.; Newman, M.; Han, W.</p> <p>2017-12-01</p> <p>The Indian Ocean has received increasing attention in recent years for its large impacts on regional and global climate. However, due mainly to the close interdependence of the climate variation within the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> and the Indian Ocean, the internal sea surface temperature (SST) variability within the Indian Ocean has not been studied extensively on longer time scales. In this presentation we will show analysis of the interannual to decadal SST variability in the <span class="hlt">Tropical</span> Indian Ocean in observations and Linear Inverse Model (LIM) results. We also compare the decoupled Indian Ocean SST variability from the <span class="hlt">Pacific</span> against fully coupled one based on LIM integrations, to test the factors influence the features of the leading SST modes in the Indian Ocean. The result shows the Indian Ocean Basin (IOB) mode, which is strongly related to global averaged SST variability, passively responses to the <span class="hlt">Pacific</span> variation. Without <span class="hlt">tropical</span> Indo-<span class="hlt">Pacific</span> coupling interaction, the intensity of IOB significantly decreases by 80%. The Indian Ocean Dipole (IOD) mode demonstrates its independence from the <span class="hlt">Pacific</span> SST variability since the IOD does not change its long-term characteristics at all without inter-basin interactions. The overall SSTA variance decreases significantly in the <span class="hlt">Tropical</span> Indian Ocean in the coupling restricted LIM runs, especially when the one-way impact from the <span class="hlt">Pacific</span> to the Indian Ocean is turned off, suggesting that most of the variability in the Indian Ocean comes from the <span class="hlt">Pacific</span> influence. On the other hand, the Indian Ocean could also transport anomalies to the <span class="hlt">Pacific</span>, making the interaction a complete two-way process.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatCo...712571W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatCo...712571W"><span>El Niño and coral larval dispersal across the eastern <span class="hlt">Pacific</span> marine barrier</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wood, S.; Baums, I. B.; Paris, C. B.; Ridgwell, A.; Kessler, W. S.; Hendy, E. J.</p> <p>2016-08-01</p> <p>More than 5,000 km separates the frequently disturbed coral reefs of the Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> (ETP) from western sources of population replenishment. It has been hypothesized that El Niño events facilitate eastward dispersal across this East <span class="hlt">Pacific</span> Barrier (EPB). Here we present a biophysical coral larval dispersal model driven by 14.5 years of high-resolution surface ocean current data including the extreme 1997-1998 El Niño. We find no eastward cross-EPB connections over this period, which implies that ETP coral populations decimated by the 1998 bleaching event can only have recovered from eastern <span class="hlt">Pacific</span> sources, in congruence with genetic data. Instead, rare connections between eastern and <span class="hlt">central</span> <span class="hlt">Pacific</span> reefs are simulated in a westward direction. Significant complexity and variability in the surface flows transporting larvae mean that generalized upper-ocean circulation patterns are poor descriptors of inter-regional connectivity, complicating the assessment of how climate change will impact coral gene flow <span class="hlt">Pacific</span> wide.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4996977','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4996977"><span>El Niño and coral larval dispersal across the eastern <span class="hlt">Pacific</span> marine barrier</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Wood, S.; Baums, I. B.; Paris, C. B.; Ridgwell, A.; Kessler, W. S.; Hendy, E. J.</p> <p>2016-01-01</p> <p>More than 5,000 km separates the frequently disturbed coral reefs of the Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> (ETP) from western sources of population replenishment. It has been hypothesized that El Niño events facilitate eastward dispersal across this East <span class="hlt">Pacific</span> Barrier (EPB). Here we present a biophysical coral larval dispersal model driven by 14.5 years of high-resolution surface ocean current data including the extreme 1997–1998 El Niño. We find no eastward cross-EPB connections over this period, which implies that ETP coral populations decimated by the 1998 bleaching event can only have recovered from eastern <span class="hlt">Pacific</span> sources, in congruence with genetic data. Instead, rare connections between eastern and <span class="hlt">central</span> <span class="hlt">Pacific</span> reefs are simulated in a westward direction. Significant complexity and variability in the surface flows transporting larvae mean that generalized upper-ocean circulation patterns are poor descriptors of inter-regional connectivity, complicating the assessment of how climate change will impact coral gene flow <span class="hlt">Pacific</span> wide. PMID:27550393</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29692041','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29692041"><span>[Trophic niche partitioning of pelagic sharks in <span class="hlt">Central</span> Eastern <span class="hlt">Pacific</span> inferred from stable isotope analysis.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Li, Yun Kai; Gao, Xiao di; Wang, Lin Yu; Fang, Lin</p> <p>2018-01-01</p> <p>As the apex predators of the open ocean ecosystems, pelagic sharks play important roles in stabilizing the marine food web through top-down control. Stable isotope analysis is a powerful tool to investigate the feeding ecology. The carbon and nitrogen isotope ratios can be used to trace food source and evaluate the trophic position of marine organisms. In this study, the isotope values of 130 pelagic sharks from 8 species in <span class="hlt">Central</span> Eastern <span class="hlt">Pacific</span> were analyzed and their trophic position and niche were calculated to compare the intra/inter-specific resource partitioning in the <span class="hlt">Central</span> Eastern <span class="hlt">Pacific</span> ecosystem. The results exhibited significant differences in both carbon and nitrogen isotope values among the shark species. The trophic levels ranged from 4.3 to 5.4 in the <span class="hlt">Central</span> Eastern <span class="hlt">Pacific</span> shark community. The trophic niche of blue sharks and shortfin mako sharks showed no overlap with the other shark species, exhibiting unique ecological roles in the open ocean food web. These data highlighted the diverse roles among pelagic sharks, supporting previous findings that this species is not trophically redundant and the trophic niche of pelagic sharks can not be simply replaced by those of other top predator species.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26900916','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26900916"><span>Hydrology Affects Environmental and Spatial Structuring of Microalgal Metacommunities in <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Coast Wetlands.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Rojo, Carmen; Mesquita-Joanes, Francesc; Monrós, Juan S; Armengol, Javier; Sasa, Mahmood; Bonilla, Fabián; Rueda, Ricardo; Benavent-Corai, José; Piculo, Rubén; Segura, M Matilde</p> <p>2016-01-01</p> <p>The alternating climate between wet and dry periods has important effects on the hydrology and therefore on niche-based processes of water bodies in <span class="hlt">tropical</span> areas. Additionally, assemblages of microorganism can show spatial patterns, in the form of a distance decay relationship due to their size or life form. We aimed to test spatial and environmental effects, modulated by a seasonal flooding climatic pattern, on the distribution of microalgae in 30 wetlands of a <span class="hlt">tropical</span> dry forest region: the <span class="hlt">Pacific</span> coast of Costa Rica and Nicaragua. Three surveys were conducted corresponding to the beginning, the highest peak, and the end of the hydrological year during the wet season, and species abundance and composition of planktonic and benthic microalgae was determined. Variation partitioning analysis (as explained by spatial distance or environmental factors) was applied to each seasonal dataset by means of partial redundancy analysis. Our results show that microalgal assemblages were structured by spatial and environmental factors depending on the hydrological period of the year. At the onset of hydroperiod and during flooding, neutral effects dominated community dynamics, but niche-based local effects resulted in more structured algal communities at the final periods of desiccating water bodies. Results suggest that climate-mediated effects on hydrology can influence the relative role of spatial and environmental factors on metacommunities of microalgae. Such variability needs to be accounted in order to describe accurately community dynamics in <span class="hlt">tropical</span> coastal wetlands.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4762632','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4762632"><span>Hydrology Affects Environmental and Spatial Structuring of Microalgal Metacommunities in <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Coast Wetlands</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Rojo, Carmen; Mesquita-Joanes, Francesc; Monrós, Juan S.; Armengol, Javier; Sasa, Mahmood; Bonilla, Fabián; Rueda, Ricardo; Benavent-Corai, José; Piculo, Rubén; Segura, M. Matilde</p> <p>2016-01-01</p> <p>The alternating climate between wet and dry periods has important effects on the hydrology and therefore on niche-based processes of water bodies in <span class="hlt">tropical</span> areas. Additionally, assemblages of microorganism can show spatial patterns, in the form of a distance decay relationship due to their size or life form. We aimed to test spatial and environmental effects, modulated by a seasonal flooding climatic pattern, on the distribution of microalgae in 30 wetlands of a <span class="hlt">tropical</span> dry forest region: the <span class="hlt">Pacific</span> coast of Costa Rica and Nicaragua. Three surveys were conducted corresponding to the beginning, the highest peak, and the end of the hydrological year during the wet season, and species abundance and composition of planktonic and benthic microalgae was determined. Variation partitioning analysis (as explained by spatial distance or environmental factors) was applied to each seasonal dataset by means of partial redundancy analysis. Our results show that microalgal assemblages were structured by spatial and environmental factors depending on the hydrological period of the year. At the onset of hydroperiod and during flooding, neutral effects dominated community dynamics, but niche-based local effects resulted in more structured algal communities at the final periods of desiccating water bodies. Results suggest that climate-mediated effects on hydrology can influence the relative role of spatial and environmental factors on metacommunities of microalgae. Such variability needs to be accounted in order to describe accurately community dynamics in <span class="hlt">tropical</span> coastal wetlands. PMID:26900916</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3928928','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3928928"><span>Predicting connectivity of green turtles at Palmyra Atoll, <span class="hlt">central</span> <span class="hlt">Pacific</span>: a focus on mtDNA and dispersal modelling</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Naro-Maciel, Eugenia; Gaughran, Stephen J.; Putman, Nathan F.; Amato, George; Arengo, Felicity; Dutton, Peter H.; McFadden, Katherine W.; Vintinner, Erin C.; Sterling, Eleanor J.</p> <p>2014-01-01</p> <p>Population connectivity and spatial distribution are fundamentally related to ecology, evolution and behaviour. Here, we combined powerful genetic analysis with simulations of particle dispersal in a high-resolution ocean circulation model to investigate the distribution of green turtles foraging at the remote Palmyra Atoll National Wildlife Refuge, <span class="hlt">central</span> <span class="hlt">Pacific</span>. We analysed mitochondrial sequences from turtles (n = 349) collected there over 5 years (2008–2012). Genetic analysis assigned natal origins almost exclusively (approx. 97%) to the West <span class="hlt">Central</span> and South <span class="hlt">Central</span> <span class="hlt">Pacific</span> combined Regional Management Units. Further, our modelling results indicated that turtles could potentially drift from rookeries to Palmyra Atoll via surface currents along a near-Equatorial swathe traversing the <span class="hlt">Pacific</span>. Comparing findings from genetics and modelling highlighted the complex impacts of ocean currents and behaviour on natal origins. Although the Palmyra feeding ground was highly differentiated genetically from others in the Indo-<span class="hlt">Pacific</span>, there was no significant differentiation among years, sexes or stage-classes at the Refuge. Understanding the distribution of this foraging population advances knowledge of green turtles and contributes to effective conservation planning for this threatened species. PMID:24451389</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70150325','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70150325"><span>Predicting connectivity of green turtles at Palmyra Atoll, <span class="hlt">central</span> <span class="hlt">Pacific</span>: a focus on mtDNA and dispersal modelling</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Naro-Maciel, Eugenia; Gaughran, Stephen J.; Putman, Nathan F.; Amato, George; Arengo, Felicity; Dutton, Peter H.; McFadden, Katherine W.; Vintinner, Erin C.; Sterling, Eleanor J.</p> <p>2014-01-01</p> <p>Population connectivity and spatial distribution are fundamentally related to ecology, evolution and behaviour. Here, we combined powerful genetic analysis with simulations of particle dispersal in a high-resolution ocean circulation model to investigate the distribution of green turtles foraging at the remote Palmyra Atoll National Wildlife Refuge, <span class="hlt">central</span> <span class="hlt">Pacific</span>. We analysed mitochondrial sequences from turtles (n = 349) collected there over 5 years (2008–2012). Genetic analysis assigned natal origins almost exclusively (approx. 97%) to the West <span class="hlt">Central</span> and South <span class="hlt">Central</span> <span class="hlt">Pacific</span> combined Regional Management Units. Further, our modelling results indicated that turtles could potentially drift from rookeries to Palmyra Atoll via surface currents along a near-Equatorial swathe traversing the <span class="hlt">Pacific</span>. Comparing findings from genetics and modelling highlighted the complex impacts of ocean currents and behaviour on natal origins. Although the Palmyra feeding ground was highly differentiated genetically from others in the Indo-<span class="hlt">Pacific</span>, there was no significant differentiation among years, sexes or stage-classes at the Refuge. Understanding the distribution of this foraging population advances knowledge of green turtles and contributes to effective conservation planning for this threatened species.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70176949','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70176949"><span>Current and potential impacts of mosquitoes and the pathogens they vector in the <span class="hlt">Pacific</span> region</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>LaPointe, Dennis</p> <p>2007-01-01</p> <p>Mosquitoes and the pathogens they transmit are ubiquitous throughout most of the temperate and <span class="hlt">tropical</span> regions of the world. The natural and pre-European distribution and diversity of mosquitoes and mosquito-borne diseases throughout much of the <span class="hlt">Pacific</span> region, however, depicts a depauperate and relatively benign fauna reinforcing the dream of “paradise regained”. In the <span class="hlt">central</span> and South <span class="hlt">Pacific</span> few mosquito species were able to colonize the remotest islands and atolls. Native mosquitoes are limited to a few far-ranging species and island endemics are typically restricted to the genera of Aedes and Culex. Only lymphatic filariasis appears to have been present as an endemic mosquito-borne disease before European contact. In nearby Australia, however, some 242 species of mosquitoes are known to occur and more than 70 arboviruses have been identified (Mackenzie 1999). In this regard Australia is more similar to the rest of the <span class="hlt">tropic</span> and subtropical world than the smaller islands of Oceania. In our ever-shrinking world of global commerce, military activity and travel, the nature of mosquito-borne disease in the <span class="hlt">Pacific</span> was bound to change. This paper is a brief summary of introduced mosquitoes in the <span class="hlt">Pacific</span> and their potential impacts on human and wildlife health.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRC..121.6351A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRC..121.6351A"><span>Bomb-produced radiocarbon in the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean: Guam coral reveals operation-specific signals from the <span class="hlt">Pacific</span> Proving Grounds</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Andrews, Allen H.; Asami, Ryuji; Iryu, Yasufumi; Kobayashi, Donald R.; Camacho, Frank</p> <p>2016-08-01</p> <p>High-resolution radiocarbon (14C) analyses on a coral core extracted from Guam, a western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> island, revealed a series of early bomb-produced 14C spikes. The typical marine bomb 14C signal—phase lagged and attenuated relative to atmospheric records—is present in the coral and is consistent with other regional coral records. However, 14C levels well above what can be attributed to air-sea diffusion alone punctuate this pattern. This anomaly was observed in other Indo-<span class="hlt">Pacific</span> coral records, but the Guam record is unmatched in magnitude and temporal resolution. The Guam coral Δ14C record provided three spikes in 1954-1955, 1956-1957, and 1958-1959 that are superimposed on a normal 14C record. Relative to mean prebomb levels, the first peak rises an incredible ˜700‰ and remained elevated for ˜1.2 years. A follow up assay with finer resolution increased the peak by ˜300‰. Subsequent spikes were less intense with a rise of ˜35 and ˜70‰. Each can be linked to thermonuclear testing in the <span class="hlt">Pacific</span> Proving Grounds at Bikini and Enewetak atolls in Operations Castle (1954), Redwing (1956), and Hardtack I (1958). These 14C signals can be explained by vaporization of coral reef material in the nuclear fireball, coupled with neutron activation of atmospheric nitrogen (14C production), and subsequent absorption of 14CO2 to form particulate carbonates of close-in fallout. The lag time in reaching Guam and other coral records abroad was tied to ocean surface currents and modeling provided validation of 14C arrival observations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014GeoRL..41.4332C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014GeoRL..41.4332C"><span>Effects of monsoon trough interannual variation on <span class="hlt">tropical</span> cyclogenesis over the western North <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cao, Xi; Li, Tim; Peng, Melinda; Chen, Wen; Chen, Guanghua</p> <p>2014-06-01</p> <p>The western North <span class="hlt">Pacific</span> monsoon trough (MT) exhibits marked interannual variation (IAV) associated with El Niño-Southern Oscillation forcing. The role of MT IAV in <span class="hlt">tropical</span> cyclone (TC) development was investigated using the Advanced Research Weather Research and Forecasting model placed on a beta plane. It was found that MT IAV has a great influence on vortex development. In strong years, the MT provides more favorable environmental conditions—primarily through enhanced low-level vorticity, convergence and midlevel moisture—for TC formation and vice versa in weak years. Sensitivity experiments that separated the dynamic and thermodynamic (moisture) factors from strong MT IAV showed that the thermodynamic impact associated with MT IAV is comparable to the dynamic impact.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://images.nasa.gov/#/details-GSFC_20171208_Archive_e001013.html','SCIGOVIMAGE-NASA'); return false;" href="https://images.nasa.gov/#/details-GSFC_20171208_Archive_e001013.html"><span>A Triple <span class="hlt">Tropical</span> Tempest Train: Karina, Lowell, Mariest</span></a></p> <p><a target="_blank" href="https://images.nasa.gov/">NASA Image and Video Library</a></p> <p></p> <p>2014-08-22</p> <p>NASA and NOAA satellites are studying the triple <span class="hlt">tropical</span> tempests that are now romping through the Eastern <span class="hlt">Pacific</span> Ocean. NOAA's GOES-West satellite captured <span class="hlt">Tropical</span> Storm Karina, <span class="hlt">Tropical</span> Storm Lowell and newly formed <span class="hlt">Tropical</span> Storm Marie on August 22. NOAA's GOES-West satellite captured all three storms in an infrared image at 0900 UTC (5 a.m. EDT), and <span class="hlt">Tropical</span> Lowell clearly dwarfs Karina to its west, and Marie to the east. The infrared image was created at NASA/NOAA's GOES Project at the NASA Goddard Space Flight Center in Greenbelt, Maryland. For more information about Lowell, visit: www.nasa.gov/content/goddard/12e-eastern-<span class="hlt">pacific</span>-ocean/ For more information about Karina, visit: www.nasa.gov/content/goddard/karina-eastern-<span class="hlt">pacific</span>/ Rob Gutro NASA's Goddard Space Flight Center NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002JCli...15..586S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002JCli...15..586S"><span>Anatomy of North <span class="hlt">Pacific</span> Decadal Variability.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schneider, Niklas; Miller, Arthur J.; Pierce, David W.</p> <p>2002-03-01</p> <p> rain in the KOE region.The preponderance of variance at decadal timescales in the KOE results from the integration of stochastic Ekman pumping along Rossby wave trajectories. The Ekman pumping is primarily due to atmospheric variability that expresses itself worldwide including in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. A positive feedback between the coupled model KOE SST (driven by the ocean streamfunction) and North <span class="hlt">Pacific</span> Ekman pumping is consistent with the enhanced variance of the coupled model at 20-30-yr periods. However, the time series are too short to unambiguously distinguish this positive feedback hypothesis from sampling variability. No evidence is found for a midlatitude gyre ocean-atmosphere delayed negative feedback loop.Comparisons with available observations confirm the seasonality of the forcing, the up to 5-yr time lag between like-signed <span class="hlt">central</span> North <span class="hlt">Pacific</span> and KOE SST anomalies, and the associated damping of SST in the KOE region by the latent heat flux. The coupled model results also suggest that observed SST anomalies in the KOE region may be predictable from the history of the wind-stress curl over the North <span class="hlt">Pacific</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3444395','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3444395"><span>Knowledge exchange in the <span class="hlt">Pacific</span>: The <span class="hlt">TROPIC</span> (Translational Research into Obesity Prevention Policies for Communities) project</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p></p> <p>2012-01-01</p> <p>Background Policies targeting obesogenic environments and behaviours are critical to counter rising obesity rates and lifestyle-related non-communicable diseases (NCDs). Policies are likely to be most effective and enduring when they are based on the best available evidence. Evidence-informed policy making is especially challenging in countries with limited resources. The <span class="hlt">Pacific</span> <span class="hlt">TROPIC</span> (Translational Research for Obesity Prevention in Communities) project aims to implement and evaluate a tailored knowledge-brokering approach to evidence-informed policy making to address obesity in Fiji, a <span class="hlt">Pacific</span> nation challenged by increasingly high rates of obesity and concomitant NCDs. Methods The <span class="hlt">TROPIC</span> project draws on the concept of ‘knowledge exchange’ between policy developers (individuals; organisations) and researchers to deliver a knowledge broking programme that maps policy environments, conducts workshops on evidence-informed policy making, supports the development of evidence-informed policy briefs, and embeds evidence-informed policy making into organisational culture. Recruitment of government and nongovernment organisational representatives will be based on potential to: develop policies relevant to obesity, reach broad audiences, and commit to resourcing staff and building a culture that supports evidence-informed policy development. Workshops will increase awareness of both obesity and policy cycles, as well as develop participants’ skills in accessing, assessing and applying relevant evidence to policy briefs. The knowledge-broking team will then support participants to: 1) develop evidence-informed policy briefs that are both commensurate with national and organisational plans and also informed by evidence from the <span class="hlt">Pacific</span> Obesity Prevention in Communities project and elsewhere; and 2) collaborate with participating organisations to embed evidence-informed policy making structures and processes. This knowledge broking initiative will be evaluated via</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28322846','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28322846"><span>Did biogeographical processes shape the monogenean community of butterflyfishes in the <span class="hlt">tropical</span> Indo-west <span class="hlt">Pacific</span> region?</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Reverter, M; Cribb, T H; Cutmore, S C; Bray, R A; Parravicini, V; Sasal, P</p> <p>2017-07-01</p> <p>Geographical distribution of parasite species can provide insights into the evolution and diversity of parasitic communities. Biogeography of marine parasites is poorly known, especially because it requires an understanding of host-parasite interactions, information that is rare, especially over large spatial scales. Here, we have studied the biogeographical patterns of dactylogyrid parasites of chaetodontids, one of the most well-studied fish families, in the <span class="hlt">tropical</span> Indo-west <span class="hlt">Pacific</span> region. Dactylogyrid parasites were collected from gills of 34 butterflyfish species (n=560) at nine localities within an approximate area of 62millionkm 2 . Thirteen dactylogyrid species were identified, with richness ranging from 6 to 12 species at individual localities. Most dactylogyrid communities were dominated by Haliotrema angelopterum or Haliotrema aurigae, for which relative abundance was negatively correlated (ρ=-0.59). Parasite richness and diversity were highest in French Polynesia and the Great Barrier Reef (Australia) and lowest in Palau. Three biogeographic regions were identified based on dactylogyrid dissimilarities: French Polynesia, characterised by the dominance of H. angelopterum, the western <span class="hlt">Pacific</span> region dominated by H. aurigae, and Ningaloo Reef (Australia), dominated by Euryhaliotrema berenguelae. Structure of host assemblages was the main factor explaining the dissimilarity (turnover and nestedness components of the Bray-Curtis dissimilarity and overall Bray-Curtis dissimilarity) of parasite communities between localities, while environment was only significant in the turnover of parasite communities and overall dissimilarity. Spatial structure of localities explained only 10% of the turnover of parasite communities. The interaction of the three factors (host assemblages, environment and spatial structure), however, explained the highest amounts of variance of the dactylogyrid communities, indicating a strong colinearity between the factors. Our findings</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ClDy...50.4263Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ClDy...50.4263Z"><span>Seasonal dependence of the predictable low-level circulation patterns over the <span class="hlt">tropical</span> Indo-<span class="hlt">Pacific</span> domain</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Tuantuan; Huang, Bohua; Yang, Song; Laohalertchai, Charoon</p> <p>2018-06-01</p> <p>The seasonal dependence of the prediction skill of 850-hPa monthly zonal wind over the <span class="hlt">tropical</span> Indo-<span class="hlt">Pacific</span> domain is examined using the ensemble reforecasts for 1983-2010 from the National Centers for Environmental Prediction (NCEP) Climate Forecast System Reanalysis and Reforecast (CFSRR) project. According to a maximum signal-to-noise empirical orthogonal function analysis, the most predictable patterns of atmospheric low-level circulation are associated with the developing and maturing phases of El Niño-Southern Oscillation (ENSO). The CFSv2 is capable of predicting these ENSO-related patterns up to 9-months in advance for all months, except for May-June when the effect of the spring barrier is strong. The other predictable climate processes associated with the low-level atmospheric circulation are more seasonally dependent. For winter and spring, the second most predictable patterns are associated with the ENSO decaying phase. Within these seasons, the monthly evolution of the predictable patterns is characterized by a southward shift of westerly wind anomalies, generated by the interaction between the annual cycle and the ENSO signals (i.e., the combination-mode). In general, the CFSv2 hindcast well predicts these patterns at least 5 months in advance for spring, while shows much lower skills for winter months. In summer, the second predictable patterns are associated with the western North <span class="hlt">Pacific</span> (WNP) monsoon (i.e., the WNP anticyclone/cyclone) in short leads while associated with ENSO in longer leads (after 4-month lead). The second predictable patterns in fall are mainly associated with <span class="hlt">tropical</span> Indian Ocean Dipole, which can be predicted 3 months in advance.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70171472','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70171472"><span>Changes to extreme wave climates of islands within the Western <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> throughout the 21st century under RCP 4.5 and RCP 8.5, with implications for island vulnerability and sustainability</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Shope, James B.; Storlazzi, Curt; Erikson, Li; Hegermiller, Christie</p> <p>2016-01-01</p> <p>Waves are the dominant influence on coastal morphology and ecosystem structure of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> islands. Wave heights, periods, and directions for the 21st century were projected using near-surface wind fields from four atmosphere-ocean coupled global climate models (GCM) under representative concentration pathways (RCP) 4.5 and 8.5. GCM-derived wind fields forced the global WAVEWATCH-III wave model to generate hourly time-series of bulk wave parameters around 25 islands in the mid to western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean for historical (1976–2005), mid-, and end-of-century time periods. Extreme significant wave heights decreased (~10.0%) throughout the 21st century under both climate scenarios compared to historical wave conditions and the higher radiative forcing 8.5 scenario displayed a greater and more widespread decrease in extreme significant wave heights compared to the lower forcing 4.5 scenario. An exception was for the end-of-century June–August season. Offshore of islands in the <span class="hlt">central</span> equatorial <span class="hlt">Pacific</span>, extreme significant wave heights displayed the largest changes from historical values. The frequency of extreme events during December–February decreased under RCP 8.5, whereas the frequency increased under RCP 4.5. Mean wave directions often rotated more than 30° clockwise at several locations during June–August, which could indicate a weakening of the trade winds’ influence on extreme wave directions and increasing dominance of Southern Ocean swell or eastern shift of storm tracks. The projected changes in extreme wave heights, directions of extreme events, and frequencies at which extreme events occur will likely result in changes to the morphology and sustainability of island nations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20000085549','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20000085549"><span>Contributions of <span class="hlt">Tropical</span> Cyclones to the North Atlantic Climatological Rainfall as Observed from Satellites</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rodgers, Edward B.; Adler, Robert F.; Pierce, Harold F.; Einaudi, Franco (Technical Monitor)</p> <p>2000-01-01</p> <p>The <span class="hlt">tropical</span> cyclone rainfall climatology study that was performed for the North <span class="hlt">Pacific</span> was extended to the North Atlantic. Similar to the North <span class="hlt">Pacific</span> <span class="hlt">tropical</span> cyclone study, mean monthly rainfall within 444 km of the center of the North Atlantic <span class="hlt">tropical</span> cyclones (i.e., that reached storm stage and greater) was estimated from passive microwave satellite observations during, an eleven year period. These satellite-observed rainfall estimates were used to assess the impact of <span class="hlt">tropical</span> cyclone rainfall in altering the geographical, seasonal, and inter-annual distribution of the North Atlantic total rainfall during, June-November when <span class="hlt">tropical</span> cyclones were most abundant. The main results from this study indicate: 1) that <span class="hlt">tropical</span> cyclones contribute, respectively, 4%, 3%, and 4% to the western, eastern, and entire North Atlantic; 2) similar to that observed in the North <span class="hlt">Pacific</span>, the maximum in North Atlantic <span class="hlt">tropical</span> cyclone rainfall is approximately 5 - 10 deg poleward (depending on longitude) of the maximum non-<span class="hlt">tropical</span> cyclone rainfall; 3) <span class="hlt">tropical</span> cyclones contribute regionally a maximum of 30% of the total rainfall 'northeast of Puerto Rico, within a region near 15 deg N 55 deg W, and off the west coast of Africa; 4) there is no lag between the months with maximum <span class="hlt">tropical</span> cyclone rainfall and non-<span class="hlt">tropical</span> cyclone rainfall in the western North Atlantic, while in the eastern North Atlantic, maximum <span class="hlt">tropical</span> cyclone rainfall precedes maximum non-<span class="hlt">tropical</span> cyclone rainfall; 5) like the North <span class="hlt">Pacific</span>, North Atlantic <span class="hlt">tropical</span> cyclones Of hurricane intensity generate the greatest amount of rainfall in the higher latitudes; and 6) warm ENSO events inhibit <span class="hlt">tropical</span> cyclone rainfall.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23342527','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23342527"><span>Crustaceans from a <span class="hlt">tropical</span> estuarine sand-mud flat, <span class="hlt">Pacific</span>, Costa Rica, (1984-1988) revisited.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Vargas-Zamora, José A; Sibaja-Cordero, Jeffrey A; Vargas-Castillo, Rita</p> <p>2012-12-01</p> <p>The availability of data sets for time periods of more than a year is scarce for <span class="hlt">tropical</span> environments. Advances in hardware and software speed-up the re-analysis of old data sets and facilitates the description of population oscillations. Using recent taxonomic literature and software we have updated and re-analized the information on crustacean diversity and population fluctuations from a set of cores collected at a mud-sand flat in the mid upper Gulf of Nicoya estuary, <span class="hlt">Pacific</span> coast of Costa Rica (1984-1988). A total of 112 morphological species of macroinvertebrates was found, of which 29 were crustaceans. Taxonomic problems, maily with the peracarids, prevented the identification of a group of species. The abundance patterns of the crab Pinnixa valerii, the ostracod Cyprideis pacifica, and the cumacean Coricuma nicoyensis were analized with the Generalized Additive Models of the free software R. The models evidenced a variety of population oscillations during the sampling period. These oscillations probably included perturbations induced by external factors, like the strong red tide events of 1985. In additon, early on 1984 the populations might have been at an altered state due to the inpact of El Niño 1982-83. Thus, the oscillations observed during the study period departed from the expected seasonality (dry vs rainy) pattern and are thus considered atypical for this <span class="hlt">tropical</span> estuarine tidal-flat. Crustacean diversity and population peaks were within the range of examples found in worldwide literature. However, abundances of the cumacean C. nicoyensis, an endemic species, are the highest reported for a <span class="hlt">tropical</span> estuary. Comparative data from <span class="hlt">tropical</span> tidal flat crustaceans continues to be scarce. Crustaceans (total vs groups) had population changes in response to the deployment of predator exclusion cages during the dry and rainy seasons of 1985. Temporal and spatial patchiness characterized the abundances of P. valeri, C. pacifica and C. nicoyenis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840016446','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840016446"><span>Preliminary study of microtektites first discovered in the <span class="hlt">central</span> <span class="hlt">Pacific</span> by China</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hanchang, P.; Shong, Y.; Xi, M.; Shijie, S.</p> <p>1984-01-01</p> <p>Electron probe analysis was used to determine the chemical composition of microtektites discovered in the <span class="hlt">Central</span> <span class="hlt">Pacific</span>. An X-ray energy spectrum analysis was made, and the surface microstructure was investigated. The found microtektites appear to be younger than the microtektites reported in the Asia Australia Strewn Field.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/FR-2012-08-10/pdf/2012-19642.pdf','FEDREG'); return false;" href="https://www.gpo.gov/fdsys/pkg/FR-2012-08-10/pdf/2012-19642.pdf"><span>77 FR 47918 - Chicago <span class="hlt">Central</span> and <span class="hlt">Pacific</span> Railroad Company-Abandonment Exemption-in Cook County, IL</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR">Federal Register 2010, 2011, 2012, 2013, 2014</a></p> <p></p> <p>2012-08-10</p> <p>... <span class="hlt">Central</span> and <span class="hlt">Pacific</span> Railroad Company--Abandonment Exemption--in Cook County, IL Chicago <span class="hlt">Central</span> and... North Riverside, Cook County, Ill. The line traverses United States Postal Service Zip Codes 60546 and... system. A copy of any petition filed with the Board should be sent to CCP's representative: Thomas J...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA514364','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA514364"><span>Analysis of a Non-Developing <span class="hlt">Tropical</span> Circulation System During the <span class="hlt">Tropical</span> Cyclone Structure (TCS08) Field Experiment</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2009-12-01</p> <p>Research and Predictability Experiment (THORPEX) <span class="hlt">Pacific</span> Asian Regional Campaigns (T- PARC ). Aircraft dropwindsondes, special ELDORA radar observations...systems within TCS025 at 2030 UTC 24 August 2008. D. ELDORA BACKGROUND For the combined TCS08 and T- PARC field experiment, the ELDORA radar was...SUBJECT TERMS Electra Doppler Radar (ELDORA), <span class="hlt">Tropical</span> Cyclone Structure (TCS08), TCS08, <span class="hlt">Tropical</span> Cyclone Formation, <span class="hlt">Tropical</span> Circulation System</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ClDy...50..705D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ClDy...50..705D"><span>Is the poleward migration of <span class="hlt">tropical</span> cyclone maximum intensity associated with a poleward migration of <span class="hlt">tropical</span> cyclone genesis?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Daloz, Anne Sophie; Camargo, Suzana J.</p> <p>2018-01-01</p> <p>A recent study showed that the global average latitude where <span class="hlt">tropical</span> cyclones achieve their lifetime-maximum intensity has been migrating poleward at a rate of about one-half degree of latitude per decade over the last 30 years in each hemisphere. However, it does not answer a critical question: is the poleward migration of <span class="hlt">tropical</span> cyclone lifetime-maximum intensity associated with a poleward migration of <span class="hlt">tropical</span> cyclone genesis? In this study we will examine this question. First we analyze changes in the environmental variables associated with <span class="hlt">tropical</span> cyclone genesis, namely entropy deficit, potential intensity, vertical wind shear, vorticity, skin temperature and specific humidity at 500 hPa in reanalysis datasets between 1980 and 2013. Then, a selection of these variables is combined into two <span class="hlt">tropical</span> cyclone genesis indices that empirically relate <span class="hlt">tropical</span> cyclone genesis to large-scale variables. We find a shift toward greater (smaller) average potential number of genesis at higher (lower) latitudes over most regions of the <span class="hlt">Pacific</span> Ocean, which is consistent with a migration of <span class="hlt">tropical</span> cyclone genesis towards higher latitudes. We then examine the global best track archive and find coherent and significant poleward shifts in mean genesis position over the <span class="hlt">Pacific</span> Ocean basins.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014OcScD..11.2205C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014OcScD..11.2205C"><span>Circulation, eddies, oxygen and nutrient changes in the eastern <span class="hlt">tropical</span> South <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Czeschel, R.; Stramma, L.; Weller, R. A.; Fischer, T.</p> <p>2014-09-01</p> <p>A large, subsurface oxygen deficiency zone is located in the eastern <span class="hlt">tropical</span> South <span class="hlt">Pacific</span> Ocean (ETSP). The large-scale circulation in the eastern equatorial <span class="hlt">Pacific</span> and off Peru in November/December 2012 shows the influence of the equatorial current system, the eastern boundary currents, and the northern reaches of the subtropical gyre. In November 2012 the Equatorial Undercurrent is centered at 250 m depth, deeper than in earlier observations. In December 2012 the equatorial water is transported southeastward near the shelf in the Peru-Chile Undercurrent with a mean transport of 1.6 Sv. In the oxygen minimum zone (OMZ) the flow is overlaid with strong eddy activity on the poleward side of the OMZ. Floats with parking depth at 400 m show fast westward flow in the mid-depth equatorial channel and sluggish flow in the OMZ. Floats with oxygen sensors clearly show the passage of eddies with oxygen anomalies. The long-term float observations in the upper ocean lead to a net community production estimate at about 18° S of up to 16.7 mmol C m-3 yr1 extrapolated to an annual rate and 7.7 mmol C m-3 yr-1 for the time period below the mixed layer. Oxygen differences between repeated ship sections are influenced by the Interdecadal <span class="hlt">Pacific</span> Oscillation, by the phase of El Niño, by seasonal changes, and by eddies and hence have to be interpreted with care. At and south of the equator the decrease in oxygen in the upper ocean since 1976 is related to an increase in nitrate, phosphate, and in part in silicate.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015OcSci..11..455C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015OcSci..11..455C"><span>Circulation, eddies, oxygen, and nutrient changes in the eastern <span class="hlt">tropical</span> South <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Czeschel, R.; Stramma, L.; Weller, R. A.; Fischer, T.</p> <p>2015-06-01</p> <p>A large subsurface oxygen deficiency zone is located in the eastern <span class="hlt">tropical</span> South <span class="hlt">Pacific</span> Ocean (ETSP). The large-scale circulation in the eastern equatorial <span class="hlt">Pacific</span> and off the coast of Peru in November/December 2012 shows the influence of the equatorial current system, the eastern boundary currents, and the northern reaches of the subtropical gyre. In November 2012 the equatorial undercurrent (EUC) is centered at 250 m depth, deeper than in earlier observations. In December 2012, the equatorial water is transported southeastward near the shelf in the Peru-Chile undercurrent (PCUC) with a mean transport of 1.4 Sv. In the oxygen minimum zone (OMZ), the flow is overlaid with strong eddy activity on the poleward side of the OMZ. Floats with parking depth at 400 m show fast westward flow in the mid-depth equatorial channel and sluggish flow in the OMZ. Floats with oxygen sensors clearly show the passage of eddies with oxygen anomalies. The long-term float observations in the upper ocean lead to a net community production estimate at about 18° S of up to 16.7 mmol C m-3 yr-1 extrapolated to an annual rate and 7.7 mmol C m-3 yr-1 for the time period below the mixed layer. Oxygen differences between repeated ship sections are influenced by the Interdecadal <span class="hlt">Pacific</span> Oscillation (IPO), by the phase of El Niño, by seasonal changes, and by eddies, and hence have to be interpreted with care. At and south of the Equator the decrease in oxygen in the upper ocean since 1976 is related to an increase in nitrate, phosphate, and in part silicate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140013023','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140013023"><span>Temperature Trends in the <span class="hlt">Tropical</span> Upper Troposphere and Lower Stratosphere: Connections with Sea Surface Temperatures and Implications for Water Vapor and Ozone</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Garfinkel, C. I.; Waugh, D. W.; Oman, L. D.; Wang, L.; Hurwitz, M. M.</p> <p>2013-01-01</p> <p>Satellite observations and chemistry-climate model experiments are used to understand the zonal structure of <span class="hlt">tropical</span> lower stratospheric temperature, water vapor, and ozone trends. The warming in the <span class="hlt">tropical</span> upper troposphere over the past 30 years is strongest near the Indo-<span class="hlt">Pacific</span> warm pool, while the warming trend in the western and <span class="hlt">central</span> <span class="hlt">Pacific</span> is much weaker. In the lower stratosphere, these trends are reversed: the historical cooling trend is strongest over the Indo-<span class="hlt">Pacific</span> warm pool and is weakest in the western and <span class="hlt">central</span> <span class="hlt">Pacific</span>. These zonal variations are stronger than the zonal-mean response in boreal winter. Targeted experiments with a chemistry-climate model are used to demonstrate that sea surface temperature (hereafter SST) trends are driving the zonal asymmetry in upper tropospheric and lower stratospheric <span class="hlt">tropical</span> temperature trends. Warming SSTs in the Indian Ocean and in the warm pool region have led to enhanced moist heating in the upper troposphere, and in turn to a Gill-like response that extends into the lower stratosphere. The anomalous circulation has led to zonal structure in the ozone and water vapor trends near the tropopause, and subsequently to less water vapor entering the stratosphere. The radiative impact of these changes in trace gases is smaller than the direct impact of the moist heating. Projected future SSTs appear to drive a temperature and water vapor response whose zonal structure is similar to the historical response. In the lower stratosphere, the changes in water vapor and temperature due to projected future SSTs are of similar strength to, though slightly weaker than, that due directly to projected future CO2, ozone, and methane.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20000083879','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20000083879"><span>A Sea-Surface Radiation Data Set for Climate Applications in the <span class="hlt">Tropical</span> Western <span class="hlt">Pacific</span> and South China Sea</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Chou, Ming-Dah; Chan, Pui-King; Yan, Michael M.-H.</p> <p>2000-01-01</p> <p>The sea-surface shortwave and longwave radiative fluxes have been retrieved from the radiances measured by Japan's Geostationary Meteorological Satellite 5. The surface radiation data set covers the domain 40S-40N and 90E-170W. The temporal resolution is 1 day, and the spatial resolution is 0.5 deg x 0.5 deg latitude-longitude. The retrieved surface radiation have been validated with the radiometric measurements at the Atmospheric Radiation Measuring (ARM) site on Manus island in the equatorial western <span class="hlt">Pacific</span> for a period of 15 months. It has also been validated with the measurements at the radiation site on Dungsha island in the South China Sea during the South China Sea Monsoon Experiment (SCSMEX) Intensive Observing Period (May and June 1998). The data set is used to study the effect of El Nino and East Asian Summer monsoon on the heating of the ocean in the <span class="hlt">tropical</span> western <span class="hlt">Pacific</span> and the South China Sea. Interannual variations of clouds associated with El Nino and the East Asian Summer monsoon have a large impact on the radiative heating of the ocean. It has been found that the magnitude of the interannual variation of the seasonal mean surface radiative heating exceeds 40 W/sq m over large areas. Together with the Clouds and the Earth's Radiant Energy System (CERES) shortwave fluxes at top of the atmosphere and the radiative transfer calculations of clear-sky fluxes, this surface radiation data set is also used to study the impact of clouds on the solar heating of the atmosphere. It is found that clouds enhance the atmospheric solar heating by approx. 20 W/sq m in the <span class="hlt">tropical</span> western <span class="hlt">Pacific</span> and the South China Sea. This result is important for evaluating the accuracy of solar flux calculations in clear and cloudy atmospheres.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMOS53C1704L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMOS53C1704L"><span>Dissolved and Particulate 230Th - 232Th systematics in the <span class="hlt">Central</span> Equatorial <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lopez, G. I.; Marcantonio, F.</p> <p>2013-12-01</p> <p>To complement our work in the eastern Equatorial <span class="hlt">Pacific</span>, we have measured total and dissolved 230Th and 232Th in the <span class="hlt">central</span> Equatorial <span class="hlt">Pacific</span> at two sites, one at 8°N and the other at the equator (ML1208-03CTD; 00° 13.166' S, 155° 57.668' W and ML1208-12CTD; 8° 19.989' N, 159° 18.000' W). The two seawater casts were collected in May 2012 during an NSF-funded "Line Islands" cruise to test for the extent of advection or diffusion of dissolved 230Th from the oligotrophic North <span class="hlt">Pacific</span> gyre (low particle flux) to the more productive equatorial region (high particle flux). Our thorium results are similar to previous data published for the western and <span class="hlt">central</span> North <span class="hlt">Pacific</span> Ocean. Dissolved 230Th concentrations range from 1.1 fg/kg at 100 m to 30.8 fg/kg at 4400 m, while dissolved 232Th concentrations span from 8.1 pg/kg at 900 m to 19.7 pg/kg at 4400 m. The pattern of the dissolved 230Th profile at 8°N is essentially linear from the surface to 2000 m. From 2000 m to 3000 m, the dissolved 230Th concentrations are constant, and then from 3000 m to the bottom, the profile is linear again. At the same site, the particulate fraction of the total seawater 230Th increases exponentially from about 0% at the surface to 38% at 4400 m. From 0 to 3000 m at 8°N, dissolved 232Th concentrations display a relatively constant pattern (variability of about 20%). From 3000 m to 4400 m, dissolved 232Th contents are more variable, but generally increase toward greater depths. The proportion of 232Th in the particulate fraction of the total seawater sample increases exponentially with depth to a value of 58% in the bottommost sample. We will present additional data from the equator and assess the particulate dynamics that control the distribution of thorium isotopes in <span class="hlt">central</span> equatorial <span class="hlt">Pacific</span> seawater.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20000038106&hterms=kalman+filter&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dkalman%2Bfilter','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20000038106&hterms=kalman+filter&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dkalman%2Bfilter"><span>An Extended Kalman Filter to Assimilate Altimetric Data into a Non-Linear Model of the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gourdeau, L.; Verron, J.; Murtugudde, R.; Busalacchi, A. J.</p> <p>1997-01-01</p> <p>A new implementation of the extended Kaman filter is developed for the purpose of assimilating altimetric observations into a primitive equation model of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. Its specificity consists in defining the errors into a reduced basis that evolves in time with the model dynamic. Validation by twin experiments is conducted and the method is shown to be efficient in quasi real conditions. Data from the first 2 years of the Topex/Poseidon mission are assimilated into the Gent & Cane [1989] model. Assimilation results are evaluated against independent in situ data, namely TAO mooring observations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26564801','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26564801"><span>Combined effects of recent <span class="hlt">Pacific</span> cooling and Indian Ocean warming on the Asian monsoon.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ueda, Hiroaki; Kamae, Youichi; Hayasaki, Masamitsu; Kitoh, Akio; Watanabe, Shigeru; Miki, Yurisa; Kumai, Atsuki</p> <p>2015-11-13</p> <p>Recent research indicates that the cooling trend in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean over the past 15 years underlies the contemporaneous hiatus in global mean temperature increase. During the hiatus, the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean displays a La Niña-like cooling pattern while sea surface temperature (SST) in the Indian Ocean has continued to increase. This SST pattern differs from the well-known La Niña-induced basin-wide cooling across the Indian Ocean on the interannual timescale. Here, based on model experiments, we show that the SST pattern during the hiatus explains pronounced regional anomalies of rainfall in the Asian monsoon region and thermodynamic effects due to specific humidity change are secondary. Specifically, Indo-<span class="hlt">Pacific</span> SST anomalies cause convection to intensify over the <span class="hlt">tropical</span> western <span class="hlt">Pacific</span>, which in turn suppresses rainfall in mid-latitude East Asia through atmospheric teleconnection. Overall, the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> SST effect opposes and is greater than the Indian Ocean SST effect.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMPP21B1986S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMPP21B1986S"><span>Lake sediment isotope records of hydroclimatic changes in the <span class="hlt">Pacific</span> Northwest over the last two thousand years</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Steinman, B. A.; Abbott, M.; Mann, M. E.; Ortiz, J. D.</p> <p>2012-12-01</p> <p>Recent drought conditions and greater water demand caused by population expansion are placing increasing stress on the ecosystems and economies of western North America. Variations in drought frequency and intensity in this region are primarily controlled by the El Niño Southern Oscillation (ENSO) and the <span class="hlt">Pacific</span> Decadal Oscillation (PDO), which affect precipitation and temperature on interannual to centennial timescales. During the Little Ice Age (LIA) and Medieval Climate Anomaly (MCA) the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean was likely characterized by shifts toward more El Niño and La Niña like mean state conditions, respectively, which produced changes in water availability that have no historic precedent. Here we report isotopic evidence (sediment δ18O records) from 9 lakes in the southern Yukon, <span class="hlt">central</span> British Columbia, and the northwestern United States indicating that the LIA was a time of exceptional dryness in the <span class="hlt">Pacific</span> Northwest and that the MCA was relatively wetter. We compare the lake sediment isotope data to synoptic ocean-atmosphere paleoproxy datasets as well as records of external forcing (i.e., solar and volcanic) that span the last 1-2 thousand years to ascertain the influence of climate system responses to external forcing on precipitation-evaporation balance in western North America. Modeling and proxy data comparisons have described links between the mean state of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean and radiative forcing on multi-decadal to centennial time scales during the middle and late Holocene. Analysis of proxy data including tree rings and speleothems have documented connections between inferred solar activity maxima, La Niña like conditions in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> and reduced water availability in the American southwest. Lake sediment δ18O data from the <span class="hlt">Pacific</span> Northwest evince a pattern opposite that of the southwest in which periods of greater solar activity correspond with wetter hydroclimatic conditions, and vice versa, similar to the observed</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMOS41B1817L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMOS41B1817L"><span>Lower Boundary Forcing related to the Occurrence of Rain in the <span class="hlt">Tropical</span> Western <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Y.; Carbone, R. E.</p> <p>2013-12-01</p> <p>Global weather and climate models have a long and somewhat tortured history with respect to simulation and prediction of <span class="hlt">tropical</span> rainfall in the relative absence of balanced flow in the geostrophic sense. An important correlate with <span class="hlt">tropical</span> rainfall is sea surface temperature (SST). The introduction of SST information to convective rainfall parameterization in global models has improved model climatologies of <span class="hlt">tropical</span> oceanic rainfall. Nevertheless, large systematic errors have persisted, several of which are common to most atmospheric models. Models have evolved to the point where increased spatial resolution demands representation of the SST field at compatible temporal and spatial scales, leading to common usage of monthly SST fields at scales of 10-100 km. While large systematic errors persist, significant skill has been realized from various atmospheric and coupled ocean models, including assimilation of weekly or even daily SST fields, as tested by the European Center for Medium Range Weather Forecasting. A few investigators have explored the role of SST gradients in relation to the occurrence of precipitation. Some of this research has focused on large scale gradients, mainly associated with surface ocean-atmosphere climatology. These studies conclude that lower boundary atmospheric convergence, under some conditions, could be substantially enhanced over SST gradients, destabilizing the atmosphere, and thereby enabling moist convection. While the concept has a firm theoretical foundation, it has not gained a sizeable following far beyond the realm of western boundary currents. Li and Carbone 2012 examined the role of transient mesoscale (~ 100 km) SST gradients in the western <span class="hlt">Pacific</span> warm pool by means of GHRSST and CMORPH rainfall data. They found that excitation of deep moist convection was strongly associated with the Laplacian of SST (LSST). Specifically, -LSST is associated with rainfall onset in 75% of 10,000 events over 4 years, whereas the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3281911','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3281911"><span>There's No Place Like Home: Crown-of-Thorns Outbreaks in the <span class="hlt">Central</span> <span class="hlt">Pacific</span> Are Regionally Derived and Independent Events</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Timmers, Molly A.; Bird, Christopher E.; Skillings, Derek J.; Smouse, Peter E.; Toonen, Robert J.</p> <p>2012-01-01</p> <p>One of the most significant biological disturbances on a <span class="hlt">tropical</span> coral reef is a population outbreak of the fecund, corallivorous crown-of-thorns sea star, Acanthaster planci. Although the factors that trigger an initial outbreak may vary, successive outbreaks within and across regions are assumed to spread via the planktonic larvae released from a primary outbreak. This secondary outbreak hypothesis is predominantly based on the high dispersal potential of A. planci and the assertion that outbreak populations (a rogue subset of the larger population) are genetically more similar to each other than they are to low-density non-outbreak populations. Here we use molecular techniques to evaluate the spatial scale at which A. planci outbreaks can propagate via larval dispersal in the <span class="hlt">central</span> <span class="hlt">Pacific</span> Ocean by inferring the location and severity of gene flow restrictions from the analysis of mtDNA control region sequence (656 specimens, 17 non-outbreak and six outbreak locations, six archipelagos, and three regions). Substantial regional, archipelagic, and subarchipelagic-scale genetic structuring of A. planci populations indicate that larvae rarely realize their dispersal potential and outbreaks in the <span class="hlt">central</span> <span class="hlt">Pacific</span> do not spread across the expanses of open ocean. On a finer scale, genetic partitioning was detected within two of three islands with multiple sampling sites. The finest spatial structure was detected at Pearl & Hermes Atoll, between the lagoon and forereef habitats (<10 km). Despite using a genetic marker capable of revealing subtle partitioning, we found no evidence that outbreaks were a rogue genetic subset of a greater population. Overall, outbreaks that occur at similar times across population partitions are genetically independent and likely due to nutrient inputs and similar climatic and ecological conditions that conspire to fuel plankton blooms. PMID:22363570</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://images.nasa.gov/#/details-GSFC_20171208_Archive_e001015.html','SCIGOVIMAGE-NASA'); return false;" href="https://images.nasa.gov/#/details-GSFC_20171208_Archive_e001015.html"><span><span class="hlt">Tropical</span> Storm Lowell Becomes 7th Eastern <span class="hlt">Pacific</span> Hurricane</span></a></p> <p><a target="_blank" href="https://images.nasa.gov/">NASA Image and Video Library</a></p> <p></p> <p>2014-08-21</p> <p>NOAA's GOES-West satellite watched as <span class="hlt">Tropical</span> Storm Lowell strengthened into a large hurricane during the morning of August 21 and opened its eye. Hurricane force winds extend outward up to 60 miles (95 km) from the center, while <span class="hlt">tropical</span> storm force winds extend outward up to 185 miles (295 km). The storm stretches over a greater distance. Lowell became the seventh hurricane of the Eastern <span class="hlt">Pacific</span> Ocean season today, August 21 at 11 a.m. EDT (1500 UTC). Maximum sustained winds had increased to 75 mph (120 kph) making Lowell a Category One hurricane on the Saffir-Simpson Wind Scale. Little change in intensity is forecast by the National Hurricane Center (NHC) today, and NHC forecasters expect a slow weakening trend later today through August 22. It was centered near latitude 20.0 north and longitude 122.1 west, about 810 miles (1,300 km) west-southwest of the southern tip of Baja California, Mexico. It is moving to the northwest near 3 mph (4 kph) and is expected to move faster in that direction over the next two days. The NHC said that Lowell should begin to slowly weaken by August 22 as it moves over progressively cooler waters and into a drier and more stable air mass. Since Lowell is such a large cyclone, it will likely take longer than average to spin down. The GOES-West image of Lowell was created at the NASA/NOAA GOES Project, located at NASA's Goddard Space Flight Center in Greenbelt, Maryland. Rob Gutro NASA's Goddard Space Flight Center Credit: NOAA/NASA GOES Project NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950036149&hterms=SSM&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DSSM','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950036149&hterms=SSM&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DSSM"><span>Rainfall variability over the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> from July 1987 through December 1991 as inferred via monthly estimates from SSM/I</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Berg, Wesley; Avery, Susan K.</p> <p>1994-01-01</p> <p>Estimates of monthly rainfall have been computed over the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> using passive microwave satellite observations from the Special Sensor Microwave/Imager (SSM/I) for the preiod from July 1987 through December 1991. The monthly estimates were calibrated using measurements from a network of <span class="hlt">Pacific</span> atoll rain gauges and compared to other satellite-based rainfall estimation techniques. Based on these monthly estimates, an analysis of the variability of large-scale features over intraseasonal to interannual timescales has been performed. While the major precipitation features as well as the seasonal variability distributions show good agreement with expected values, the presence of a moderately intense El Nino during 1986-87 and an intense La Nina during 1988-89 highlights this time period.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008PrOce..77..331K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008PrOce..77..331K"><span>Oxygen minimum zones in the eastern <span class="hlt">tropical</span> Atlantic and <span class="hlt">Pacific</span> oceans</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Karstensen, Johannes; Stramma, Lothar; Visbeck, Martin</p> <p>2008-06-01</p> <p>Within the eastern <span class="hlt">tropical</span> oceans of the Atlantic and <span class="hlt">Pacific</span> basin vast oxygen minimum zones (OMZ) exist in the depth range between 100 and 900 m. Minimum oxygen values are reached at 300-500 m depth which in the eastern <span class="hlt">Pacific</span> become suboxic (dissolved oxygen content <4.5 μmol kg -1) with dissolved oxygen concentration of less than 1 μmol kg -1. The OMZ of the eastern Atlantic is not suboxic and has relatively high oxygen minimum values of about 17 μmol kg -1 in the South Atlantic and more than 40 μmol kg -1 in the North Atlantic. About 20 (40%) of the North <span class="hlt">Pacific</span> volume is occupied by an OMZ when using 45 μmol kg -1 (or 90 μmol kg -1, respectively) as an upper bound for OMZ oxygen concentration for ocean densities lighter than σθ < 27.2 kg m -3. The relative volumes reduce to less than half for the South <span class="hlt">Pacific</span> (7% and 13%, respectively). The abundance of OMZs are considerably smaller (1% and 7%) for the South Atlantic and only ∼0% and 5% for the North Atlantic. Thermal domes characterized by upward displacements of isotherms located in the northeastern <span class="hlt">Pacific</span> and Atlantic and in the southeastern Atlantic are co-located with the centres of the OMZs. They seem not to be directly involved in the generation of the OMZs. OMZs are a consequence of a combination of weak ocean ventilation, which supplies oxygen, and respiration, which consumes oxygen. Oxygen consumption can be approximated by the apparent oxygen utilization (AOU). However, AOU scaled with an appropriate consumption rate (aOUR) gives a time, the oxygen age. Here we derive oxygen ages using climatological AOU data and an empirical estimate of aOUR. Averaging oxygen ages for main thermocline isopycnals of the Atlantic and <span class="hlt">Pacific</span> Ocean exhibit an exponential increase with density without an obvious signature of the OMZs. Oxygen supply originates from a surface outcrop area and can also be approximated by the turn-over time, the ratio of ocean volume to ventilating flux. The turn-over time</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20160003512','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20160003512"><span>Overview of the Airborne <span class="hlt">Tropical</span> TRopopause EX</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Singh, Hanwant B.; Jensen, Eric J.; Pfister, Leonhard</p> <p>2014-01-01</p> <p>The NASA Airborne <span class="hlt">Tropical</span> TRopopause EXperiment (ATTREX) is a series of airborne campaigns focused on understanding physical processes in the <span class="hlt">Tropical</span> Tropopause Layer (TTL) and their role in atmospheric chemistry and climate. ATTREX is using the high-altitude, long-duration NASA Global Hawk Unmanned Air System to make in situ and remote-sensing measurements spanning the <span class="hlt">Pacific</span>. A particular ATIREX emphasis is to better understand the dehydration of air as it passes through the cold <span class="hlt">tropical</span> tropopause region. The ATTREX payload contains 12 in situ and remote sensing instruments that measure water vapor, clouds, multiple gaseous tracers (CO, CO2, CH4, NMHC, SF6, CFCs, N2O), reactive chemical compounds (O3, BrO, NO2), meteorological parameters, and radiative fluxes. ATTREX flight series have been conducted in the fall of 2011 from Armstrong Flight Research Center (AFRC) in California, in the winter of 2013 from AFRC, and in the winter/spring of 2014 from Guam. The first two f light series provided extensive sampling of the <span class="hlt">central</span> and eastern <span class="hlt">Pacific</span>, whereas the last flight series permitted sampling in the western <span class="hlt">Pacific</span>. The sampling strategy has primarily involved repeated ascents and descents through the depth of the TTL (about 13-19 km). Over 100 TTL profiles were obtained on each flight series. The ATTREX dataset includes TTL water vapor measurements with unprecedented accuracy, ice crystal size distributions and habits. The cloud and water measurements provide unique information about TTL cloud formation, the persistence of supersaturation with respect to ice, and dehydration. The plethora of tracers measured on the Global Hawk flights are providing unique information about TTL transport pathways and time scales. The meteorological measurements are revealing dynamical phenomena controlling the TTL thermal structure, and the radiation measurements are providing information about heating rates associated with TTL clouds and water vapor. This presentation</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/FR-2012-06-19/pdf/2012-14852.pdf','FEDREG'); return false;" href="https://www.gpo.gov/fdsys/pkg/FR-2012-06-19/pdf/2012-14852.pdf"><span>77 FR 36487 - Proposed Information Collection; Comment Request; Western and <span class="hlt">Central</span> <span class="hlt">Pacific</span> Fisheries...</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR">Federal Register 2010, 2011, 2012, 2013, 2014</a></p> <p></p> <p>2012-06-19</p> <p>... Collection; Comment Request; Western and <span class="hlt">Central</span> <span class="hlt">Pacific</span> Fisheries Convention Vessel Information Family of... obligations of the United States under the Convention on the Conservation and Management of Highly Migratory... of the Commission for the Conservation and Management of Highly Migratory Fish Stocks in the Western...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/FR-2011-05-27/pdf/2011-13092.pdf','FEDREG'); return false;" href="https://www.gpo.gov/fdsys/pkg/FR-2011-05-27/pdf/2011-13092.pdf"><span>76 FR 31008 - North <span class="hlt">Central</span> Iowa Rail Corridor, LLC-Acquisition Exemption-Union <span class="hlt">Pacific</span> Railroad Company</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR">Federal Register 2010, 2011, 2012, 2013, 2014</a></p> <p></p> <p>2011-05-27</p> <p>... Rail Corridor, LLC--Acquisition Exemption-- Union <span class="hlt">Pacific</span> Railroad Company North <span class="hlt">Central</span> Iowa Rail Corridor, LLC (NCIRC), a noncarrier, has filed a verified notice of exemption under 49 [[Page 31009</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110008657','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110008657"><span>Electrically-Active Convection and <span class="hlt">Tropical</span> Cyclogenesis in the Atlantic and East <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Leppert, Kenneth D., II; Petersen, Walter A.</p> <p>2011-01-01</p> <p>It has been hypothesized that deep, intense convective-scale hot towers may aid the process of <span class="hlt">tropical</span> cyclogenesis and intensification through dynamic and thermodynamic feedbacks on the larger meso-to-synoptic scale circulation. In this study, we make use of NCEP Reanalysis data and <span class="hlt">Tropical</span> Rainfall Measurement Mission (TRMM) lightning imaging sensor (LIS), precipitation radar (PR), and microwave imager (TMI) data to investigate the role that widespread and/or intense lightning-producing convection (i.e., electrically-hot towers) present in African easterly waves (AEWs) may play in <span class="hlt">tropical</span> cyclogenesis over the Atlantic, Caribbean, and East <span class="hlt">Pacific</span> regions. NCEP Reanalysis 700 hPa meridional winds for the months of June to November for the years 2001-2009 were analyzed for the domain of 5 deg. N-20 deg. N and 130 deg. W-20 deg. E in order to partition individual AEWs into northerly, southerly, trough, and ridge phases. Subsequently, information from National Hurricane Center (NHC) storm reports was used to divide the waves into developing and non-developing waves. In addition, information from the NHC reports was used to further divide the developing waves into those waves that spawned storms that only developed to <span class="hlt">tropical</span> storm strength and those that spawned storms that reached hurricane strength. The developing waves were also divided by the region in which they developed. To assess the evolution of convection associated with the AEWs as they propagated across our analysis domain, the full 130 deg. W-20 deg. E domain was divided into five longitude bands, and waves were analyzed for each band. To help determine the gross nature of the smaller convective scale, composites were created of all developing and non-developing waves as a function of AEW wave phase over the full analysis domain and each longitude band by compositing TRMM PR, TMI, LIS, and IR brightness temperature data extracted from the NASA global-merged infrared brightness temperature dataset</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002IJCli..22.1663R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002IJCli..22.1663R"><span>Interannual rainfall variability in the Amazon basin and sea-surface temperatures in the equatorial <span class="hlt">Pacific</span> and the <span class="hlt">tropical</span> Atlantic Oceans</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ronchail, Josyane; Cochonneau, Gérard; Molinier, Michel; Guyot, Jean-Loup; Chaves, Adriana Goretti De Miranda; Guimarães, Valdemar; de Oliveira, Eurides</p> <p>2002-11-01</p> <p>Rainfall variability in the Amazon basin is studied in relation to sea-surface temperatures (SSTs) in the equatorial <span class="hlt">Pacific</span> and the northern and southern <span class="hlt">tropical</span> Atlantic during the 1977-99 period, using the HiBAm original rainfall data set and complementary cluster and composite analyses.The northeastern part of the basin, north of 5 °S and east of 60 °W, is significantly related with <span class="hlt">tropical</span> SSTs: a rainier wet season is observed when the equatorial <span class="hlt">Pacific</span> and the northern (southern) <span class="hlt">tropical</span> Atlantic are anomalously cold (warm). A shorter and drier wet season is observed during El Niño events and negative rainfall anomalies are also significantly associated with a warm northern Atlantic in the austral autumn and a cold southern Atlantic in the spring. The northeastern Amazon rainfall anomalies are closely related with El Niño-southern oscillation during the whole year, whereas the relationships with the <span class="hlt">tropical</span> Atlantic SST anomalies are mainly observed during the autumn. A time-space continuity is observed between El Niño-related rainfall anomalies in the northeastern Amazon, those in the northern Amazon and south-eastern Amazon, and those in northern South America and in the Nordeste of Brazil.A reinforcement of certain rainfall anomalies is observed when specific oceanic events combine. For instance, when El Niño and cold SSTs in the southern Atlantic are associated, very strong negative anomalies are observed in the whole northern Amazon basin. Nonetheless, the comparison of the cluster and the composite analyses results shows that the rainfall anomalies in the northeastern Amazon are not always associated with <span class="hlt">tropical</span> SST anomalies.In the southern and western Amazon, significant <span class="hlt">tropical</span> SST-related rainfall anomalies are very few and spatially variable. The precipitation origins differ from those of the northeastern Amazon: land temperature variability, extratropical perturbations and moisture advection are important rainfall factors, as well</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20000086612','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20000086612"><span>Effect of Radiative Cooling on Cloud-SST Relationship within the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Region</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sui, Chung-Hsiung; Ho, Chang-Hoi; Chou, Ming-Dah; Lau, Ka-Ming; Li, Xiao-Fan; Einaudi, Franco (Technical Monitor)</p> <p>2000-01-01</p> <p>A recent analysis found a negative correlation between the area-mean cloud amount and the corresponding mean Sea Surface Temperature (SST) within the cloudy areas. The SST-cloud relation becomes more evident when the SST contrast between warm pool and surrounding cold pool (DSST) in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> is stronger than normal. The above feature is related to the finding that the strength of subsidence over the cold pool is limited by radiative cooling because of its small variability. As a result, the area of radiatively-driven subsidence must expand in response to enhanced low-boundary forcing due to SST warming or enhanced basin-scale DSST. This leads to more cloud free regions and less cloudy regions. The increased ratio of cloud-free areas to cloudy areas leads to more high SST areas (>29.50C) due to enhanced solar radiation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3153452','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3153452"><span>Population Genetics of an Ecosystem-Defining Reef Coral Pocillopora damicornis in the <span class="hlt">Tropical</span> Eastern <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Combosch, David J.; Vollmer, Steven V.</p> <p>2011-01-01</p> <p>Background Coral reefs in the <span class="hlt">Tropical</span> Eastern <span class="hlt">Pacific</span> (TEP) are amongst the most peripheral and geographically isolated in the world. This isolation has shaped the biology of TEP organisms and lead to the formation of numerous endemic species. For example, the coral Pocillopora damicornis is a minor reef-builder elsewhere in the Indo-West <span class="hlt">Pacific</span>, but is the dominant reef-building coral in the TEP, where it forms large, mono-specific stands, covering many hectares of reef. Moreover, TEP P. damicornis reproduces by broadcast spawning, while it broods mostly parthenogenetic larvae throughout the rest of the Indo-West <span class="hlt">Pacific</span>. Population genetic surveys for P. damicornis from across its Indo-<span class="hlt">Pacific</span> range indicate that gene flow (i.e. larval dispersal) is generally limited over hundreds of kilometers or less. Little is known about the population genetic structure and the dispersal potential of P. damicornis in the TEP. Methodology Using multilocus microsatellite data, we analyzed the population structure of TEP P. damicornis among and within nine reefs and test for significant genetic structure across three geographically and ecologically distinct regions in Panama. Principal Findings/Conclusions We detected significant levels of population genetic structure (global RST = 0.162), indicating restricted gene flow (i.e. larvae dispersal), both among the three regions (RRT = 0.081) as well as within regions (RSR = 0.089). Limited gene flow across a distinct environmental cline, like the regional upwelling gradient in Panama, indicates a significant potential for differential adaptation and population differentiation. Individual reefs were characterized by unexpectedly high genet diversity (avg. 94%), relatively high inbreeding coefficients (global FIS = 0.183), and localized spatial genetic structure among individuals (i.e. unique genets) over 10 m intervals. These findings suggest that gene flow is limited in TEP P. damicornis populations, particularly</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1918417F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1918417F"><span>The role of external forcing and <span class="hlt">Pacific</span> trade winds in recent changes of the global climate system</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Friedman, Andrew; Gastineau, Guillaume; Khodri, Myriam</p> <p>2017-04-01</p> <p>The <span class="hlt">Pacific</span> trade winds experienced an unprecedented strengthening since the mid 1990s. Several studies have proposed that the increased <span class="hlt">Pacific</span> trade winds were associated with the reduced rate of global mean surface temperature warming in the first decade of the 21st century, as well as far-reaching atmospheric teleconnections. We designed a set of ensemble partial coupling experiments using the IPSL-CM5A-LR coupled model that allow us to cleanly distinguish the influence of <span class="hlt">Pacific</span> trade wind variability from that of external forcing over the past few decades. In this study, we quantify the respective impacts of these processes on surface temperature, ocean heat content, and atmospheric teleconnections. We designed two ensembles of coupled simulations using partial coupling with the IPSL-CM5A-LR model to separate the <span class="hlt">Pacific</span> internal variability and that of external radiative forcing. We prescribe surface wind stress in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> (20°S to 20°N) from 1979-2014 in two ensembles of 30 members each: (1) Prescribed climatological model wind stress, which allows us to estimate the influence of external radiative forcing in the absence of variability within the <span class="hlt">Pacific</span> Ocean. (2) Wind stress anomalies from ERA-Interim reanalysis added to the model wind stress climatology, which accounts for the effects of both external radiative forcing and the wind stress variability. We find that the observed wind stress anomalies account for the pattern of eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> cooling when compared to the climatology experiment, so that it resembles the observed trends from 1992-2011. The <span class="hlt">tropical</span> <span class="hlt">Pacific</span> shows dominant heat uptake in the western <span class="hlt">Pacific</span> above the 20°C isotherm, which contributed to slow the warming of <span class="hlt">tropical</span> SST during the 2000s. The trade wind increase is associated with a strengthening of the <span class="hlt">Pacific</span> Walker circulation, and zonal shifts in <span class="hlt">tropical</span> rainfall. Despite <span class="hlt">tropical</span> SST biases which affect the response of <span class="hlt">tropical</span> rainfall and the</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28590557','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28590557"><span>Declines in plant palatability from polar to <span class="hlt">tropical</span> latitudes depend on herbivore and plant identity.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Demko, Alyssa M; Amsler, Charles D; Hay, Mark E; Long, Jeremy D; McClintock, James B; Paul, Valerie J; Sotka, Erik E</p> <p>2017-09-01</p> <p>Long-standing theory predicts that the intensity of consumer-prey interactions declines with increasing latitude, yet for plant-herbivore interactions, latitudinal changes in herbivory rates and plant palatability have received variable support. The topic is of growing interest given that lower-latitude species are moving poleward at an accelerating rate due to climate change, and predicting local interactions will depend partly on whether latitudinal gradients occur in these critical biotic interactions. Here, we assayed the palatability of 50 seaweeds collected from polar (Antarctica), temperate (northeastern <span class="hlt">Pacific</span>; California), and <span class="hlt">tropical</span> (<span class="hlt">central</span> <span class="hlt">Pacific</span>; Fiji) locations to two herbivores native to the <span class="hlt">tropical</span> and subtropical Atlantic, the generalist crab Mithraculus sculptus and sea urchin Echinometra lucunter. Red seaweeds (Rhodophyta) of polar and temperate origin were more readily consumed by urchins than were <span class="hlt">tropical</span> reds. The decline in palatability with decreasing latitude is explained by shifts in tissue organic content along with the quantity and quality of secondary metabolites, degree of calcification or both. We detected no latitudinal shift in palatability of red seaweeds to crabs, nor any latitudinal shifts in palatability of brown seaweeds (Phaeophyta) to either crabs or urchins. Our results suggest that evolutionary pressure from <span class="hlt">tropical</span> herbivores favored red seaweeds with lower palatability, either through the production of greater levels of chemical defenses, calcification, or both. Moreover, our results tentatively suggest that the "<span class="hlt">tropicalization</span>" of temperate habitats is facilitated by the migration of <span class="hlt">tropical</span> herbivores into temperate areas dominated by weakly defended and more nutritious foods, and that the removal of these competing seaweeds may facilitate the invasion of better-defended <span class="hlt">tropical</span> seaweeds. © 2017 by the Ecological Society of America.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010JGRD..11512128S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010JGRD..11512128S"><span>Trend discrepancies among three best track data sets of western North <span class="hlt">Pacific</span> <span class="hlt">tropical</span> cyclones</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Song, Jin-Jie; Wang, Yuan; Wu, Liguang</p> <p>2010-06-01</p> <p>The hot debate over the influence of global warming on <span class="hlt">tropical</span> cyclone (TC) activity in the western North <span class="hlt">Pacific</span> over the past several decades is partly due to the diversity of TC data sets used in recent publications. This study investigates differences of track, intensity, frequency, and the associated long-term trends for those TCs that were simultaneously recorded by the best track data sets of the Joint Typhoon Warning Center (JTWC), the Regional Specialized Meteorological Center (RSMC) Tokyo, and the Shanghai Typhoon Institute (STI). Though the differences in TC tracks among these data sets are negligibly small, the JTWC data set tends to classify TCs of category 2-3 as category 4-5, leading to an upward trend in the annual frequency of category 4-5 TCs and the annual accumulated power dissipation index, as reported by Webster et al. (2005) and Emanuel (2005). This trend and potential destructiveness over the period 1977-2007 are found only with the JTWC data set, but downward trends are apparent in the RSMC and STI data sets. It is concluded that the different algorithms used in determining TC intensity may cause the trend discrepancies of TC activity in the western North <span class="hlt">Pacific</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009aogs...12....1W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009aogs...12....1W"><span>An Equation-Free Reduced-Order Modeling Approach to <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Simulation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Ruiwen; Zhu, Jiang; Luo, Zhendong; Navon, I. M.</p> <p>2009-03-01</p> <p>The “equation-free” (EF) method is often used in complex, multi-scale problems. In such cases it is necessary to know the closed form of the required evolution equations about oscopic variables within some applied fields. Conceptually such equations exist, however, they are not available in closed form. The EF method can bypass this difficulty. This method can obtain oscopic information by implementing models at a microscopic level. Given an initial oscopic variable, through lifting we can obtain the associated microscopic variable, which may be evolved using Direct Numerical Simulations (DNS) and by restriction, we can obtain the necessary oscopic information and the projective integration to obtain the desired quantities. In this paper we apply the EF POD-assisted method to the reduced modeling of a large-scale upper ocean circulation in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> domain. The computation cost is reduced dramatically. Compared with the POD method, the method provided more accurate results and it did not require the availability of any explicit equations or the right-hand side (RHS) of the evolution equation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.A43M..05A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.A43M..05A"><span>Organic Halogen and Related Trace Gases in the <span class="hlt">Tropical</span> Atmosphere: Results from Recent Airborne Campaigns Over the <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Atlas, E. L.; Navarro, M. A.; Donets, V.; Schauffler, S.; Lueb, R.; Hendershot, R.; Gabbard, S.; Hornbrook, R. S.; Apel, E. C.; Riemer, D. D.; Pan, L.; Salawitch, R. J.; Nicely, J. M.; Montzka, S. A.; Miller, B.; Moore, F. L.; Elkins, J. W.; Hintsa, E. J.; Campos, T. L.; Quack, B.; Zhu, X.; Pope, L.</p> <p>2014-12-01</p> <p>Organic halogen gases, especially containing bromine and iodine, play a significant role as precursors to active halogen chemistry and ozone catalytic loss. Much of the reactive organic halogen originates from biological processes in the surface ocean, which can be quite variable by season and location. The <span class="hlt">tropics</span> and coastal margins are potentially important sources that are being examined. The recent coordinated CONTRAST/ATTREX/CAST missions were conducted in the Western <span class="hlt">Tropical</span> <span class="hlt">Pacific</span>, a region that is a major transport pathway for tropospheric air entering the stratosphere. One of the goals of the missions was to identify sources, distributions, and transport of organic halogens from the ocean surface into the <span class="hlt">tropical</span> lower stratosphere. The missions were conducted during the NH winter season, Jan-Feb, 2014. In this presentation, we will discuss the distributions and variability of organic halogen gases in the study region and will examine the input of organic halogen species into the <span class="hlt">Tropical</span> Tropopause Layer (TTL). Comparison with other tracers, such as methyl nitrate and NMHC, will help identify source regions for these gases. We will focus on the measurements obtained in the CONTRAST and ATTREX missions with data from in-situ GC/MS measurements and whole air samples collected on the NSF GV and NASA Global Hawk aircraft. Comparisons with other recent airborne campaigns, such as HIPPO and TC4, and with several ship-based studies will provide an additional context for evaluating the variability of organic halogen species in the <span class="hlt">tropical</span> atmosphere and their role in transporting reactive halogen compounds into the UT/LS.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRG..122.1385G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRG..122.1385G"><span>Approach for estimating the dynamic physical thresholds of phytoplankton production and biomass in the <span class="hlt">tropical</span>-subtropical <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gómez-Ocampo, E.; Gaxiola-Castro, G.; Durazo, Reginaldo</p> <p>2017-06-01</p> <p>Threshold is defined as the point where small changes in an environmental driver produce large responses in the ecosystem. Generalized additive models (GAMs) were used to estimate the thresholds and contribution of key dynamic physical variables in terms of phytoplankton production and variations in biomass in the <span class="hlt">tropical</span>-subtropical <span class="hlt">Pacific</span> Ocean off Mexico. The statistical approach used here showed that thresholds were shallower for primary production than for phytoplankton biomass (pycnocline < 68 m and mixed layer < 30 m versus pycnocline < 45 m and mixed layer < 80 m) but were similar for absolute dynamic topography and Ekman pumping (ADT < 59 cm and EkP > 0 cm d-1 versus ADT < 60 cm and EkP > 4 cm d-1). The relatively high productivity on seasonal (spring) and interannual (La Niña 2008) scales was linked to low ADT (45-60 cm) and shallow pycnocline depth (9-68 m) and mixed layer (8-40 m). Statistical estimations from satellite data indicated that the contributions of ocean circulation to phytoplankton variability were 18% (for phytoplankton biomass) and 46% (for phytoplankton production). Although the statistical contribution of models constructed with in situ integrated chlorophyll a and primary production data was lower than the one obtained with satellite data (11%), the fits were better for the former, based on the residual distribution. The results reported here suggest that estimated thresholds may reliably explain the spatial-temporal variations of phytoplankton in the <span class="hlt">tropical</span>-subtropical <span class="hlt">Pacific</span> Ocean off the coast of Mexico.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.3423G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.3423G"><span>Modulation of Subseasonal <span class="hlt">Tropical</span> Cyclone Genesis In The Western North <span class="hlt">Pacific</span> By Wave Activities</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gao, Jianyun; Cheung, Kevin K. W.</p> <p>2017-04-01</p> <p><span class="hlt">Tropical</span> cyclone (TC) activity is well known to possess variability on multiple timescales, ranging from inter-decadal to intraseasonal. In this study, the subseasonal variability of TC genesis in the western North <span class="hlt">Pacific</span> (WNP) is examined during summer (May-October) for the period of 1979-2015. In particular, clustering of TC activity within subseasonal timescale is the focus. First, three phases (active, normal and inactive phases) of TC clustering are defined based on the statistics of genesis frequency. Then the modes of subseasonal modulation of these three phases by intraseasonal (30-60-day) oscillation (ISO), biweekly (10-20-day) oscillation (BWO), and the convectively coupled equatorial waves (CCEW), including Rossby, Kelvin, and mixed Rossby-gravity and <span class="hlt">tropical</span> depression-type waves are considered. It is found that the embedding large-scale circulation is significantly different between the inactive phase and the other phases. Further, the intensities and propagation phases of the ISO, BWO and CCEW play different roles to modulate TC genesis frequency during the active and normal phase. Considering the lag correlation of these subseasonal modulation modes and TC genesis, it is possible to construct a statistical model for the purpose of extended-range forecasting of subseasonal variability of TC occurrence over the WNP.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ThApC.tmp...81S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ThApC.tmp...81S"><span>Monsoon rainfall over India in June and link with northwest <span class="hlt">tropical</span> <span class="hlt">pacific</span> - June ISMR and link with northwest <span class="hlt">tropical</span> <span class="hlt">pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Surendran, Sajani; Gadgil, Sulochana; Rajendran, Kavirajan; Varghese, Stella Jes; Kitoh, Akio</p> <p>2018-03-01</p> <p>Recent years have witnessed large interannual variation of all-India rainfall (AIR) in June, with intermittent large deficits and excesses. Variability of June AIR is found to have the strongest link with variation of rainfall over northwest <span class="hlt">tropical</span> <span class="hlt">Pacific</span> (NWTP), with AIR deficit (excess) associated with enhancement (suppression) of NWTP rainfall. This association is investigated using high-resolution Meteorological Research Institute model which shows high skill in simulating important features of Asian summer monsoon, its variability and the inverse relationship between NWTP rainfall and AIR. Analysis of the variation of NWTP rainfall shows that it is associated with a change in the latitudinal position of subtropical westerly jet over the region stretching from West of Tibetan Plateau (WTP) to NWTP and the phase of Rossby wave steered in it with centres over NWTP and WTP. In years with large rainfall excess/deficit, the strong link between AIR and NWTP rainfall exists through differences in Rossby wave phase steered in the jet. The positive phase of the WTP-NWTP pattern, with troughs over WTP and west of NWTP, tends to be associated with increased rainfall over NWTP and decreased AIR. This scenario is reversed in the opposite phase. Thus, the teleconnection between NWTP rainfall and AIR is a manifestation of the difference in the phase of Rossby wave between excess and deficit years, with centres over WTP and NWTP. This brings out the importance of prediction of phase of Rossby waves over WTP and NWTP in advance, for prediction of June rainfall over India.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29026014','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29026014"><span>Influence of El Niño on atmospheric CO2 over the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean: Findings from NASA's OCO-2 mission.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chatterjee, A; Gierach, M M; Sutton, A J; Feely, R A; Crisp, D; Eldering, A; Gunson, M R; O'Dell, C W; Stephens, B B; Schimel, D S</p> <p>2017-10-13</p> <p>Spaceborne observations of carbon dioxide (CO 2 ) from the Orbiting Carbon Observatory-2 are used to characterize the response of <span class="hlt">tropical</span> atmospheric CO 2 concentrations to the strong El Niño event of 2015-2016. Although correlations between the growth rate of atmospheric CO 2 concentrations and the El Niño-Southern Oscillation are well known, the magnitude of the correlation and the timing of the responses of oceanic and terrestrial carbon cycle remain poorly constrained in space and time. We used space-based CO 2 observations to confirm that the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean does play an early and important role in modulating the changes in atmospheric CO 2 concentrations during El Niño events-a phenomenon inferred but not previously observed because of insufficient high-density, broad-scale CO 2 observations over the <span class="hlt">tropics</span>. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRC..122.5850T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRC..122.5850T"><span>Equatorial Kelvin waves generated in the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean trigger mass and heat transport within the Middle America Trench off Costa Rica</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Thomson, Richard E.; Davis, Earl E.</p> <p>2017-07-01</p> <p>Sequences of correlated seafloor temperature, current velocity, and acoustic backscatter events recorded at Ocean Drilling Program (ODP) sites at 4300 m depth in the Middle America Trench have been inferred to result from tidally induced turbidity currents generated in the vicinity of the 3300 m deep sill at the southern end of the trench. New data from the borehole observatories extend the temperature records to 11 years (November 2002 to December 2013) and confirm the highly episodic nature of the events. We present satellite altimetry data and ocean circulation model results to show that event timing is correlated with intraseasonal Kelvin wave motions in the equatorial <span class="hlt">Pacific</span>. The observed temperature events had a mean (±1 standard deviation) occurrence interval of 61 (±24) days, which spans the periods of the first two baroclinic modes. Lag times between peak bottom water temperatures at the ODP sites and the passage of eastward-propagating Kelvin wave crests at locations in the eastern equatorial <span class="hlt">Pacific</span> are consistent with the time for mode-1 waves to propagate to the southern end of the trench at a mean phase speed of 2.0 m s-1. Findings indicate that Kelvin wave currents augment tidal motions in the vicinity of the sill, triggering turbidity currents that travel northwestward along the trench axis at mean speeds of ˜0.1 m s-1. We conclude that mode-1 (or, possibly, mixed mode-1 and mode-2) baroclinic Kelvin waves generated by large-scale atmospheric processes in the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> lead to heat and mass transport deep within Middle America Trench in the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.B31G0550L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.B31G0550L"><span>Separating the Effects of <span class="hlt">Tropical</span> Atlantic and <span class="hlt">Pacific</span> SST-driven Climate Variability on Amazon Carbon Exchange</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liptak, J.; Keppel-Aleks, G.</p> <p>2016-12-01</p> <p>Amazon forests store an estimated 25% percent of global terrestrial carbon per year1, 2, but the responses of Amazon carbon uptake to climate change is highly uncertain. One source of this uncertainty is <span class="hlt">tropical</span> sea surface temperature variability driven by teleconnections. El Nino-Southern Oscillation (ENSO) is a key driver of year-to-year Amazon carbon exchange, with associated temperature and precipitation changes favoring net carbon storage in La Nina years, and net carbon release during El Nino years3. To determine how Amazon climate and terrestrial carbon fluxes react to ENSO alone and in concert with other SST-driven teleconnections such as the Atlantic Multidecadal Oscillation (AMO), we force the atmosphere (CAM5) and land (CLM4) components of the CESM(BGC) with prescribed monthly SSTs over the period 1950—2014 in a Historical control simulation. We then run an experiment (PAC) with time-varying SSTs applied only to the <span class="hlt">tropical</span> equatorial <span class="hlt">Pacific</span> Ocean, and repeating SST seasonal cycle climatologies elsewhere. Limiting SST variability to the equatorial <span class="hlt">Pacific</span> indicates that other processes enhance ENSO-driven Amazon climate anomalies. Compared to the Historical control simulation, warming, drying and terrestrial carbon loss over the Amazon during El Nino periods are lower in the PAC simulation, especially prior to 1990 during the cool phase of the AMO. Cooling, moistening, and net carbon uptake during La Nina periods are also reduced in the PAC simulation, but differences are greater after 1990 during the warm phase of the AMO. By quantifying the relationships among climate drivers and carbon fluxes in the Historical and PAC simulations, we both assess the sensitivity of these relationships to the magnitude of ENSO forcing and quantify how other teleconnections affect ENSO-driven Amazon climate feedbacks. We expect that these results will help us improve hypotheses for how Atlantic and <span class="hlt">Pacific</span> climate trends will affect future Amazon carbon carbon</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005IJCli..25.1665W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005IJCli..25.1665W"><span>The coincidence of daily rainfall events in Liberia, Costa Rica and <span class="hlt">tropical</span> cyclones in the Caribbean basin</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Waylen, Peter R.; Harrison, Michael</p> <p>2005-10-01</p> <p>The occurrence of <span class="hlt">tropical</span> cyclones in the Caribbean and North Atlantic basins has been previously noted to have a significant effect both upon individual hydro-climatological events as well as on the quantity of annual precipitation experienced along the <span class="hlt">Pacific</span> flank of <span class="hlt">Central</span> America. A methodology for examining the so-called indirect effects of <span class="hlt">tropical</span> cyclones (i.e. those effects resulting from a <span class="hlt">tropical</span> cyclone at a considerable distance from the area of interest) on a daily rainfall record is established, which uses a variant of contingency table analysis. The method is tested using a single station on the <span class="hlt">Pacific</span> slope of Costa Rica. Employing daily precipitation records from Liberia, north-western Costa Rica (1964-1995), and historic storm tracks of <span class="hlt">tropical</span> cyclones in the North Atlantic, it is determined that precipitation falling in coincidence with the passage of <span class="hlt">tropical</span> depressions, <span class="hlt">tropical</span> storms, and hurricanes accounts for approximately 15% of average annual precipitation. The greatest effects are associated with storms passing within 1300 km of the precipitation station, and are most apparent in the increased frequency of daily rainfall totals in the range of 40-60 mm, rather than in the largest daily totals. The complexity and nonstationarity of factors affecting precipitation in this region are reflected in the decline in the number of <span class="hlt">tropical</span> cyclones and their significance to annual precipitation totals after 1980, simultaneous to an increase in annual precipitation totals. The methodology employed in this study is shown to be a useful tool in illuminating the indirect effects of <span class="hlt">tropical</span> cyclones in the region, with the potential for application in other areas.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27974156','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27974156"><span>Floating Marine Debris in waters of the Mexican <span class="hlt">Central</span> <span class="hlt">Pacific</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Díaz-Torres, Evelyn R; Ortega-Ortiz, Christian D; Silva-Iñiguez, Lidia; Nene-Preciado, Alejandro; Orozco, Ernesto Torres</p> <p>2017-02-15</p> <p>The presence of marine debris has been reported recently in several oceans basins; there is very little information available for Mexican <span class="hlt">Pacific</span> coasts, however. This research examined the composition, possible sources, distribution, and density of Floating Marine Debris (FMD) during nine research surveys conducted during 2010-2012 in the Mexican <span class="hlt">Central</span> <span class="hlt">Pacific</span> (MCP). Of 1820 floating objects recorded, 80% were plastic items. Sources of FMD were determined using key objects, which indicated that the most were related to the presence of the industrial harbor and of a growing fishing industry in the study area. Densities were relatively high, ranging from 40 to 2440objects/km 2 ; the highest densities were recorded in autumn. FMD were distributed near coastal regions, mainly in Jalisco, influenced by river outflow and surface currents. Our results seem to follow worldwide trends and highlight the need for further studies on potential ecological impacts within coastal waters of the MCP. Copyright © 2016 Elsevier Ltd. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25349499','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25349499"><span>Shallow-water zoantharians (Cnidaria, Hexacorallia) from the <span class="hlt">Central</span> Indo-<span class="hlt">Pacific</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Reimer, James D; Poliseno, Angelo; Hoeksema, Bert W</p> <p>2014-01-01</p> <p>Despite the <span class="hlt">Central</span> Indo-<span class="hlt">Pacific</span> (CIP) and the Indonesian Archipelago being a well-known region of coral reef biodiversity, particularly in the 'Coral Triangle', little published information is available on its zoantharians (Cnidaria: Hexacorallia: Zoantharia). In order to provide a basis for future research on the Indo-<span class="hlt">Pacific</span> zoantharian fauna and facilitate comparisons between more well-studied regions such as Japan and the Great Barrier Reef, this report deals with CIP zoantharian specimens in the Naturalis collection in Leiden, the Netherlands; 106 specimens were placed into 24 morpho-species and were supplemented with 88 in situ photographic records from Indonesia, the Philippines, and Papua New Guinea. At least nine morpho-species are likely to be undescribed species, indicating that the region needs more research in order to properly understand zoantharian diversity within the CIP. The Naturalis' zoantharian specimens are listed by species, as well as all relevant collection information, and in situ images are provided to aid in future studies on zoantharians in the CIP.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNH23E2846P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNH23E2846P"><span>Recent Atlantic Hurricanes, <span class="hlt">Pacific</span> Super Typhoons, and <span class="hlt">Tropical</span> Storm Awareness in Underdeveloped Island and Coastal Regions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Plondke, D. L.</p> <p>2017-12-01</p> <p>Hurricane Harvey was the first major hurricane to make landfall in the continental U.S. in 12 years. The next <span class="hlt">tropical</span> storm in the 2017 Atlantic Hurricane Season was Hurricane Irma, a category 5 storm and the strongest storm to strike the U.S. mainland since Hurricane Wilma in 2005. These two storms were the third and fourth in a sequence of 10 consecutive storms to reach hurricane status in this season that ranks at least seventh among the most active seasons as measured by the Accumulate Cyclone Energy (ACE) index. Assessment of damage from Harvey may prove it to be the costliest storm in U.S. history, approaching $190 billion. Irma was the first category 5 hurricane to hit the Leeward Islands, devastating island environments including Puerto Rico, the Virgin Islands, Barbuda, Saint Barthelemy, and Anguilla with sustained winds reaching at times 185 mph. Together with the two super typhoons of the 2017 <span class="hlt">Pacific</span> season, Noru and Lan, the two Atlantic hurricanes rank among the strongest, longest-lasting <span class="hlt">tropical</span> cyclones on record. How many more billions of dollars will be expended in recovery and reconstruction efforts following future mega-disasters comparable to those of Hurricanes Harvey and Irma? Particularly on Caribbean and <span class="hlt">tropical</span> <span class="hlt">Pacific</span> islands with specialized and underdeveloped economies, aging and substandard infrastructure often cannot even partially mitigate against the impacts of major hurricanes. The most frequently used measurements of storm impact are insufficient to assess the economic impact. Analysis of the storm tracks and periods of greatest storm intensity of Hurricanes Harvey and Irma, and Super Typhoons Lan and Noru, in spatial relationship with island and coastal administrative regions, shows that rainfall totals, flooded area estimates, and property/infrastructure damage dollar estimates are all quantitative indicators of storm impact, but do not measure the costs that result from lack of storm preparedness and education of residents</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMPP21C1347P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMPP21C1347P"><span>Mid- to Late Holocene Climate Shift in the Southern Gulf of California and <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Perez-Cruz, L. L.; Fucugauchi, J. U.; Velasco, V.; Rodriguez, A.; Choumiline, K.</p> <p>2014-12-01</p> <p>A multiproxy record has been acquired from a gravity core (DIPAL-I K47) taken in La Paz Basin, an area which is situated in the southwestern sector of the Gulf of California at the junction to the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> Ocean. The high-resolution data sets, from XRF, TOC, magnetic susceptibility and hysteresis measurements, were used to track climatic changes in the <span class="hlt">tropical</span> climate system at sub-centennial time scales over the past 7.3 cal kyr BP. The paleoprecipitation record shows variation trends, with a shift during the mid- to late Holocene, characterized by changes from high to low humidity. Pluvial, biogenic and eolian input, marked by variations in Ti, Si, Fe, K, Ca, Zr/Ti, Ca/Ti and magnetic susceptibility, shows trend changes between 7-5 cal kyr, 5-4.5 cal kyr, 4.5-3.5 cal kyr and 2.15-1.4 kyr. Drought events are recognized from 3.7 to 3.4, 2.8 to 1.8 cal kyr BP, and between 1.4 and 1.2 cal kyr BP. The southern Gulf is well suited for documenting the climatic and precipitation changes in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean associated with ITCZ latitudinal migration, PDO, ENSO events and the North American monsoon. Analysis of sourcing, transport and deposition of sediments is used for reconstructing the changing ocean-atmosphere circulation patterns, particularly sensitive to paleoprecipitation. The Bay receives sediments mainly from the surrounding volcanic ranges of the peninsular Baja California. There are no rivers in the peninsula and sediments are related to pluvial input trough ephemeral creeks along the steep cliff ranges and narrow shelf. Biogenic sediments are associated with productivity and oceanographic conditions through upwellings and mesoscale gyres. Eolian sediments are transported into the basin from the peninsula and continent, including transport of fine dust from the northern desert of Sonora-Mojave and arid terrains in the peninsula. It is important to highlight that a common 1800 yr solar variation spectral periodicity has been captured</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016E%26PSL.453....1R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016E%26PSL.453....1R"><span>Constraints on the magnitude of the deglacial migration of the ITCZ in the <span class="hlt">Central</span> Equatorial <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Reimi, Maria A.; Marcantonio, Franco</p> <p>2016-11-01</p> <p>Accurate paleo-latitudinal reconstructions of the Intertropical Convergence Zone (ITCZ) are necessary for understanding <span class="hlt">tropical</span> hydroclimate and atmospheric circulation. Paleoclimate models and records suggest that as global temperatures increase, the ITCZ should migrate towards the warmer hemisphere. Many uncertainties remain regarding the magnitude of this migration, and few studies have focused on the <span class="hlt">Central</span> Equatorial <span class="hlt">Pacific</span> (CEP). Here, we use eolian dust records recovered from three locations in the CEP to address changes in dust provenance across the paleo ITCZ since the last glacial maximum (LGM). Radiogenic isotope compositions of Nd and Pb show that dust delivered to the CEP was sourced mainly from two regions: East Asia and South America. From these data we deduced that since Marine Oxygen Isotope Stage 2 (MIS2) the ITCZ has migrated north to its modern position, being displaced by as much as 7°, to as little as 2.5°. We find that the ITCZ migrated further north during the early Holocene (∼9 kyr), reaching its position furthest north during the mid-Holocene warm interval (∼7 kyr), based on an increase in South American dust at the northernmost sites.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://cfpub.epa.gov/si/si_public_record_report.cfm?direntryid=167765','PESTICIDES'); return false;" href="https://cfpub.epa.gov/si/si_public_record_report.cfm?direntryid=167765"><span><span class="hlt">TROPICAL</span> COLLECTOR URCHIN, TRIPNEUSTES ...</span></a></p> <p><a target="_blank" href="http://www.epa.gov/pesticides/search.htm">EPA Pesticide Factsheets</a></p> <p></p> <p></p> <p>This document describes a fertilization method to estimate the chronic toxicity of effluents and receiving waters to the gametes of the <span class="hlt">tropical</span> sea urchin (Tripneustes gratilla). This toxicity test measures the fertilizing capacity of sperm following a static, non-renewal 60-minute exposure and a subsequent 20-minute exposure period following the addition of eggs. The purpose of the test is to determine the concentrations of a test substance diluted in sea water that reduce fertilization of exposed gametes relative to that of the control. This method was developed to provide an assessment of the toxicity of materials discharged into the marine environment, using biota indigenous to <span class="hlt">tropical</span> <span class="hlt">Pacific</span> regions, including Hawaii. This method provides an assessment of the toxicity to indigenous biota of materials discharged into the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> marine environment. The use of this method contributes to risk based determinations, and the scientific foundation they provide for regulatory criteria at the state, regional or national levels. General impacts from this contribution include improved understanding by managers and scientists of links between human activities, natural dynamics, ecological stressors and ecosystem condition.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.A41K3210R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.A41K3210R"><span>Subtropical Low Cloud Responses to <span class="hlt">Central</span> and Eastern <span class="hlt">Pacific</span> El Nino Events</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rapp, A. D.; Bennartz, R.; Jiang, J. H.; Kato, S.; Olson, W. S.; Pinker, R. T.; Su, H.; Taylor, P. C.</p> <p>2014-12-01</p> <p>The eastern <span class="hlt">Pacific</span> El Niño event in 2006-2007 and the <span class="hlt">central</span> <span class="hlt">Pacific</span> El Niño event during 2009-2010 exhibit opposite responses in the top of atmosphere (TOA) cloud radiative effects. These responses are driven by differences in large-scale circulation that result in significant low cloud anomalies in the subtropical southeastern <span class="hlt">Pacific</span>. Both the vertical profile of cloud fraction and cloud water content are reduced during the eastern <span class="hlt">Pacific</span> El Niño; however, the shift in the distribution of cloud characteristics and the physical processes underlying these changes need further analysis. The NASA Energy and Water Cycle Study (NEWS) Clouds and Radiation Working Group will use a synthesis of NEWS data products, A-Train satellite measurements, reanalysis, and modeling approaches to further explore the differences in the low cloud response to changes in the large-scale forcing, as well as try to understand the physical mechanism driving the observed changes in the low clouds for the 2006/07 and 2009/10 distinct El Niño events. The distributions of cloud macrophysical, microphysical, and radiative properties over the southeast <span class="hlt">Pacific</span> will first be compared for these two events using a combination of MODIS, CloudSat/CALIPSO, and CERES data. Satellite and reanalysis estimates of changes in the vertical temperature and moisture profiles, lower tropospheric stability, winds, and surface heat fluxes are then used to identify the drivers for observed differences in the clouds and TOA radiative effects.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1914543L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1914543L"><span>Mechanisms for the cooling of the <span class="hlt">central</span> eastern <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Chunlei; Allan, Richard</p> <p>2017-04-01</p> <p>The sea surface temperature variation over the <span class="hlt">Central</span> Eastern <span class="hlt">Pacific</span> (CEP) controls the global mean surface temperature variation (Kosaka and Xie, 2013). The regional cooling over CEP is directly linked to the surface warming slowdown in last twenty years. It is important to understand the mechanisms of the CEP cooling in the warming climate in order to have a robust prediction of the future climate change. Previous studies showed the CEP cooling is related to the pronounced strengthening in <span class="hlt">Pacific</span> trade winds over the past two decades, which is sufficient to account for the cooling of the CEP and a substantial slowdown in surface warming through increased subsurface ocean heat uptake in the <span class="hlt">Pacific</span> shallow overturning cells and equatorial upwelling in the CEP (England et al., 2014). By analysing the cloud data, Zhou et al. (2016) showed the increase of the lower cloud cover (LCC) over the CEP area contributed to the cooling, resulting in positive local feedback and negative global feedback. Using the data from observations, ERA-Interim reanalysis and atmospheric climate simulations, our study shows that the increasing Latent Heat (LH) also plays an important role in the CEP cooling (Liu et al., 2015). After the sensitivity test using the bulk formula, it showed that both wind and total column water vapour content contribute to the cooling trends of the SST in CEP. The observed trends of the wind and LH in CEP also confirmed this. England et al. (2014) Recent intensification of wind-driven circulation in the <span class="hlt">Pacific</span> and the ongoing warming hiatus, Nat. Clim. Change, 4, 222-227, doi:10.1038/nclimate2106. Kosaka, Y., and S. P. Xie (2013), Recent global-warming hiatus tied to equatorial <span class="hlt">Pacific</span> surface cooling, Nature, 501, 403-407, doi:10.1038/nature12534. Liu et al. (2015) Combining satellite observations and reanalysis energy transports to estimate global net surface energy fluxes 1985-2012. J. Geophys. Res. , Atmospheres. ISSN 2169-8996 doi: 10.1002/2015JD</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007E%26PSL.253...57K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007E%26PSL.253...57K"><span>Cenozoic changes in atmospheric lead recorded in <span class="hlt">central</span> <span class="hlt">Pacific</span> ferromanganese crusts</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Klemm, Veronika; Reynolds, Ben; Frank, Martin; Pettke, Thomas; Halliday, Alex N.</p> <p>2007-01-01</p> <p>The possible sources of pre-anthropogenic Pb contributed to the world's oceans have been the focus of considerable study. The role of eolian dust versus riverine inputs has been of particular interest. With better calibration of isotopic records from <span class="hlt">central</span> <span class="hlt">Pacific</span> ferromanganese crusts using Os isotope stratigraphy it now appears that deep water Pb isotopic compositions were effectively homogeneous over a distance of 5000 km for the past 80 Myr. The composition shifted slightly from high 206Pb/ 204Pb ratios in the range of 18.87 ± 0.02 before 65 Ma to lower values of 18.62 ± 0.02 by 45 Ma and then gradually increased again very slightly to the present day ratio of 18.67 ± 0.02. The regional homogeneity provides evidence of a dominant well-mixed atmospheric source the most likely candidate for which is volcanic aerosols contributed either directly or as soluble condensates on eolian dust. The slight shift in Pb isotope composition of deep waters in the <span class="hlt">central</span> <span class="hlt">Pacific</span> between 65 and 45 Ma may be the result of a regional- or perhaps global-scale change in the sources of volcanic exhalations and volcanic activity caused by an increase in the importance of melting and assimilation of older continental crustal components over the Cenozoic.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_22 --> <div id="page_23" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="441"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013DSRI...82...32S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013DSRI...82...32S"><span>Eastern and <span class="hlt">Central</span> <span class="hlt">Pacific</span> ENSO and their relationships to the recharge/discharge oscillator paradigm</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Singh, Awnesh; Delcroix, Thierry</p> <p>2013-12-01</p> <p>One of the leading theories to explain the oscillatory nature of the El Niño Southern Oscillation is the recharge-discharge oscillator paradigm, which roots on warm waters exchanged between the equatorial and off-equatorial regions. This study tests the relevance of this theory to account for the Eastern and recently mediated <span class="hlt">Central</span> <span class="hlt">Pacific</span> El Niño events. The recharge-discharge of the equatorial <span class="hlt">Pacific</span>, measured here as changes in Warm (>20 °C) Water Volume (WWV), is analysed using monthly 1993-2010 sea level anomaly (a proxy for WWV) obtained from altimetry, and a validated 1958-2007 DRAKKAR simulation. An Agglomerative Hierarchical Clustering (AHC) technique performed on the observed and modelled WWV tendency shows the existence of five distinct clusters, which characterise the Eastern <span class="hlt">Pacific</span> (EP) and <span class="hlt">Central</span> <span class="hlt">Pacific</span> (CP) El Niño, La Niña, after EP El Niño and neutral conditions. The AHC results, complemented with an analysis of lagged-regression analysis, and 3-month averages of typical EP and CP El Niño events, indicate that the equatorial band WWV discharge during CP is not as pronounced as during EP El Niño. To understand the differences, we analysed the balance of horizontal mass transports accounting for changes in WWV tendency. The analysis indicates an overall poleward transport during EP El Niño, which is not the case during CP El Niño. Instead, a compensating effect with a poleward (equatorward) transport occurring in the western (eastern) <span class="hlt">Pacific</span> is evident, in line with changes in the zonal thermocline slopes occurring in the western (eastern) half of the basin. The WWV changes are discussed with respect to the conceptual phases of the recharge-discharge oscillator paradigm.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.A12H..06Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.A12H..06Z"><span>Global Survey of Precipitation Properties Observed during <span class="hlt">Tropical</span> Cyclogenesis and Their Differences Compared to Nondeveloping Disturbances</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zawislak, J.</p> <p>2017-12-01</p> <p>This study contributes to a global survey of the precipitation properties of developing and nondeveloping <span class="hlt">tropical</span> disturbances, with a focus on distinguishing properties of those disturbances that develop into <span class="hlt">tropical</span> cyclones (TCs) from those that do not develop. Precipitation properties are quantified using a unique accumulation of overpasses of pre-genesis TCs and nondeveloping disturbances from multiple satellite-borne passive microwave imagers. The overpasses are a subset of a broader <span class="hlt">Tropical</span> Cyclone - Passive Microwave (TC-PMW) dataset that encompasses all stages of the TC life cycle. The TC-PMW consists of 14 years (2003-2016) of overpasses of pre-genesis and nondeveloping disturbances globally (the North Atlantic, East <span class="hlt">Pacific</span>, <span class="hlt">Central</span> <span class="hlt">Pacific</span>, West <span class="hlt">Pacific</span>, northern Indian Ocean, and Southern Hemisphere oceanic basins). Nondeveloping disturbances are defined as those disturbances that do not exceed an "invest" classification by the operational centers (NHC, CPHC, and JTWC). Overall, this study will offer a detailed analysis of the precipitation properties (i.e., areal coverage of rainfall and deep convection, depth, or intensity, of convection, proximity of precipitation to the center) multiple days before genesis. These analyses offer an opportunity to determine whether the properties of precipitation at, and just prior to, genesis are unique compared to previous days of the pre-genesis stage. By evaluating these properties over the robust sample provided by the TC-PMW dataset, results may lend support to the hypothesis that genesis is more closely tied to the fractional coverage of precipitation near the center rather than to any uniquely "intense" convection. The study will also investigate whether there are significant differences among the basins in the properties of precipitation involved in <span class="hlt">tropical</span> cyclogenesis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JGRD..123.3513Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JGRD..123.3513Y"><span>Stratiform and Convective Precipitation Properties of <span class="hlt">Tropical</span> Cyclones in the Northwest <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yang, Zhaohong; Yuan, Tie; Jiang, Haiyan; Zhang, Lei; Zhang, Chen</p> <p>2018-04-01</p> <p>The properties of stratiform and the convective precipitation of <span class="hlt">tropical</span> cyclones (TCs) over the northwest <span class="hlt">Pacific</span> are examined using the <span class="hlt">Tropical</span> Rainfall Measuring Mission data for 1998-2013. TCs are classified into inner core (IC), inner rainband (IB), and outer rainband (OB) regions, and the results show that TCs are dominated by stratiform precipitation, which accounts for more than 78% of the total raining area. The highest fraction of the stratiform raining area exists in the IB region and increases as the TC intensity increases (from 80% to 93%). Strong convective signatures generally occur in the IC region, less often in the IB region, and least often in the OB region. Stratiform precipitation in the IC region generally has comparable or even stronger ice scattering signatures and higher 20 dBZ radar echo heights than the convective precipitation in the IB and OB regions. Weak convection decreases significantly as the TC intensity increases, which leads to increased convective intensity. Stratiform (convective) precipitation accounts for 61% (39%) of the total TC volumetric rain and 25% (75%) of the total TC lightning flash, respectively. Moreover, stratiform precipitation's contribution to the total TC volumetric rain and lightning flash increases as the TC intensity increases, which indicates that stronger TCs are favorable for maintaining more stratiform precipitation. The stratiform and convective precipitation properties in different TC regions and intensities cooperatively change with the enhanced ascending branch in the IC region and the radial outflow at the upper levels of the secondary circulation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20160001334','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20160001334"><span>Overview of the Airborne <span class="hlt">Tropical</span> TRopopause EXperiment (ATTREX)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Jensen, Eric</p> <p>2015-01-01</p> <p>The NASA Airborne <span class="hlt">Tropical</span> TRopopause EXperiment (ATTREX) is a series of airborne campaigns focused on understanding physical processes in the <span class="hlt">Tropical</span> Tropopause Layer (TTL) and their role in atmospheric chemistry and climate. ATTREX is using the high-altitude, long-duration NASA Global Hawk Unmanned Air System to make in situ and remote-sensing measurements spanning the <span class="hlt">Pacific</span>. A particular ATTREX emphasis is to better understand the dehydration of air as it passes through the cold <span class="hlt">tropical</span> tropopause region. The ATTREX payload contains 12 in situ and remote sensing instruments that measure water vapor, clouds, multiple gaseous tracers (CO, CO2, CH4, NMHC, SF6, CFCs, N2O), reactive chemical compounds (O3, BrO, NO2), meteorological parameters, and radiative fluxes. ATTREX flight series have been conducted in the fall of 2011 from Armstrong Flight Research Center (AFRC) in California, in the winter of 2013 from AFRC, and in the winter/spring of 2014 from Guam. The first two flight series provided extensive sampling of the <span class="hlt">central</span> and eastern <span class="hlt">Pacific</span>, whereas the last flight series permitted sampling in the western <span class="hlt">Pacific</span>. The sampling strategy has primarily involved repeated ascents and descents through the depth of the TTL (about 13-19 km). Over 100 TTL profiles were obtained on each flight series. The ATTREX dataset includes TTL water vapor measurements with unprecedented accuracy, ice crystal size distributions and habits. The cloud and water measurements provide unique information about TTL cloud formation, the persistence of super-saturation with respect to ice, and dehydration. The plethora of tracers measured on the Global Hawk flights are providing unique information about TTL transport pathways and time scales. The meteorological measurements are revealing dynamical phenomena controlling the TTL thermal structure, and the radiation measurements are providing information about heating rates associated with TTL clouds and water vapor. This presentation</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28724896','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28724896"><span>Unprecedented drought over <span class="hlt">tropical</span> South America in 2016: significantly under-predicted by <span class="hlt">tropical</span> SST.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Erfanian, Amir; Wang, Guiling; Fomenko, Lori</p> <p>2017-07-19</p> <p><span class="hlt">Tropical</span> and sub-<span class="hlt">tropical</span> South America are highly susceptible to extreme droughts. Recent events include two droughts (2005 and 2010) exceeding the 100-year return value in the Amazon and recurrent extreme droughts in the Nordeste region, with profound eco-hydrological and socioeconomic impacts. In 2015-2016, both regions were hit by another drought. Here, we show that the severity of the 2015-2016 drought ("2016 drought" hereafter) is unprecedented based on multiple precipitation products (since 1900), satellite-derived data on terrestrial water storage (since 2002) and two vegetation indices (since 2004). The ecohydrological consequences from the 2016 drought are more severe and extensive than the 2005 and 2010 droughts. Empirical relationships between rainfall and sea surface temperatures (SSTs) over the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> and Atlantic are used to assess the role of <span class="hlt">tropical</span> oceanic variability in the observed precipitation anomalies. Our results indicate that warmer-than-usual SSTs in the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> (including El Niño events) and Atlantic were the main drivers of extreme droughts in South America, but are unable to explain the severity of the 2016 observed rainfall deficits for a substantial portion of the Amazonia and Nordeste regions. This strongly suggests potential contribution of non-oceanic factors (e.g., land cover change and CO2-induced warming) to the 2016 drought.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://images.nasa.gov/#/details-GSFC_20171208_Archive_e000534.html','SCIGOVIMAGE-NASA'); return false;" href="https://images.nasa.gov/#/details-GSFC_20171208_Archive_e000534.html"><span>NASA Sees Hurricane Olaf Move into <span class="hlt">Central</span> <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="https://images.nasa.gov/">NASA Image and Video Library</a></p> <p></p> <p>2017-12-08</p> <p>On Oct. 19 at 19:35 UTC (3:35 p.m. EDT) the MODIS instrument aboard NASA's Terra satellite saw Hurricane Olaf moving into the <span class="hlt">central</span> <span class="hlt">Pacific</span> Ocean with a visible eye. Powerful thunderstorms circled the eye and extended in a thick band in the eastern quadrant from north to south. At 5 a.m. EDT (0900 UTC) on Oct. 20, Hurricane Olaf's center was located near latitude 10.3 north and longitude 140.4 west. That's about 1,175 miles (1,890 km) east-southeast of Hilo, Hawaii. Despite being so far from Hawaii and because Olaf is a powerful hurricane, large swells generated by Olaf will begin to arrive along east facing shores of the main Hawaiian Islands over the next couple of days. The CPHC said that resultant surf will be large...potentially life-threatening and damaging. Olaf is moving toward the west-northwest near 10 mph (17 kph) and the <span class="hlt">Central</span> <span class="hlt">Pacific</span> Hurricane Center (CPHC), who has taken over forecast responsibilities now that Olaf has crossed the 140 degree longitude line, expects Olaf to turn toward the west-northwest and then northwest by October 21. Maximum sustained winds are near 150 mph (240 kph). Olaf is a category four hurricane on the Saffir-Simpson Hurricane wind scale. Some additional strengthening is forecast on Tuesday, Oct. 20 and fluctuations in intensity are possible Tuesday night and Wednesday. The estimated minimum <span class="hlt">central</span> pressure is 938 millibars. Olaf is expected to remain a major hurricane for the next couple of days and begin curving to the northeast and away from Hawaii by Friday, October 23. For updates, visit: www.prh.noaa.gov/cphc. Credit: NASA Goddard's MODIS Rapid Response Team NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17051216','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17051216"><span>Eastern <span class="hlt">Pacific</span> cooling and Atlantic overturning circulation during the last deglaciation.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kienast, Markus; Kienast, Stephanie S; Calvert, Stephen E; Eglinton, Timothy I; Mollenhauer, Gesine; François, Roger; Mix, Alan C</p> <p>2006-10-19</p> <p>Surface ocean conditions in the equatorial <span class="hlt">Pacific</span> Ocean could hold the clue to whether millennial-scale global climate change during glacial times was initiated through <span class="hlt">tropical</span> ocean-atmosphere feedbacks or by changes in the Atlantic thermohaline circulation. North Atlantic cold periods during Heinrich events and millennial-scale cold events (stadials) have been linked with climatic changes in the <span class="hlt">tropical</span> Atlantic Ocean and South America, as well as the Indian and East Asian monsoon systems, but not with <span class="hlt">tropical</span> <span class="hlt">Pacific</span> sea surface temperatures. Here we present a high-resolution record of sea surface temperatures in the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> derived from alkenone unsaturation measurements. Our data show a temperature drop of approximately 1 degrees C, synchronous (within dating uncertainties) with the shutdown of the Atlantic meridional overturning circulation during Heinrich event 1, and a smaller temperature drop of approximately 0.5 degrees C synchronous with the smaller reduction in the overturning circulation during the Younger Dryas event. Both cold events coincide with maxima in surface ocean productivity as inferred from 230Th-normalized carbon burial fluxes, suggesting increased upwelling at the time. From the concurrence of equatorial <span class="hlt">Pacific</span> cooling with the two North Atlantic cold periods during deglaciation, we conclude that these millennial-scale climate changes were probably driven by a reorganization of the oceans' thermohaline circulation, although possibly amplified by <span class="hlt">tropical</span> ocean-atmosphere interaction as suggested before.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20070020528&hterms=trend+reports&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dtrend%2Breports','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20070020528&hterms=trend+reports&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dtrend%2Breports"><span>Trends in Upper-Level Cloud Cover and Surface Divergence Over the <span class="hlt">Tropical</span> Indo-<span class="hlt">Pacific</span> Ocean Between 1952 And 1997</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Norris, Joel R.</p> <p>2005-01-01</p> <p>This study investigated the spatial pattern of linear trends in surface-observed upper-level (combined mid-level and High-level) cloud cover, precipitation, and surface divergence over the <span class="hlt">tropical</span> Indo-<span class="hlt">Pacific</span> Ocean during 1952-1957. Cloud values were obtained from the Extended Edited Cloud Report Archive (EECRA), precipitation values were obtained from the Hulme/Climate Research Unit Data Set, and surface divergence was alternatively calculated from wind reported Comprehensive Ocean-Atmosphere Data Set and from Smith and Reynolds Extended Reconstructed sea level pressure data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://images.nasa.gov/#/details-PIA00556.html','SCIGOVIMAGE-NASA'); return false;" href="https://images.nasa.gov/#/details-PIA00556.html"><span>Warm Ocean Temperatures Blanket the Far-Western <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="https://images.nasa.gov/">NASA Image and Video Library</a></p> <p></p> <p>2001-03-28</p> <p>Data taken during a 10-day collection cycle ending March 9, 2001, show that above-normal sea-surface heights and warmer ocean temp. red and white areas still blanket the far-western <span class="hlt">tropical</span> <span class="hlt">Pacific</span> and much of the north and south mid-<span class="hlt">Pacific</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28974676','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28974676"><span><span class="hlt">Tropical</span> explosive volcanic eruptions can trigger El Niño by cooling <span class="hlt">tropical</span> Africa.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Khodri, Myriam; Izumo, Takeshi; Vialard, Jérôme; Janicot, Serge; Cassou, Christophe; Lengaigne, Matthieu; Mignot, Juliette; Gastineau, Guillaume; Guilyardi, Eric; Lebas, Nicolas; Robock, Alan; McPhaden, Michael J</p> <p>2017-10-03</p> <p>Stratospheric aerosols from large <span class="hlt">tropical</span> explosive volcanic eruptions backscatter shortwave radiation and reduce the global mean surface temperature. Observations suggest that they also favour an El Niño within 2 years following the eruption. Modelling studies have, however, so far reached no consensus on either the sign or physical mechanism of El Niño response to volcanism. Here we show that an El Niño tends to peak during the year following large eruptions in simulations of the Fifth Coupled Model Intercomparison Project (CMIP5). Targeted climate model simulations further emphasize that Pinatubo-like eruptions tend to shorten La Niñas, lengthen El Niños and induce anomalous warming when occurring during neutral states. Volcanically induced cooling in <span class="hlt">tropical</span> Africa weakens the West African monsoon, and the resulting atmospheric Kelvin wave drives equatorial westerly wind anomalies over the western <span class="hlt">Pacific</span>. This wind anomaly is further amplified by air-sea interactions in the <span class="hlt">Pacific</span>, favouring an El Niño-like response.El Niño tends to follow 2 years after volcanic eruptions, but the physical mechanism behind this phenomenon is unclear. Here the authors use model simulations to show that a Pinatubo-like eruption cools <span class="hlt">tropical</span> Africa and drives westerly wind anomalies in the <span class="hlt">Pacific</span> favouring an El Niño response.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20060025554','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20060025554"><span>Overview of the Field Phase of the NASA <span class="hlt">Tropical</span> Cloud Systems and Processes (TCSP)Experiment</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hood, Robbie E.; Zipser, Edward; Heymsfield, Gerald M.; Kakar, Ramesh; Halverson Jeffery; Rogers, Robert; Black, Michael</p> <p>2006-01-01</p> <p>The <span class="hlt">Tropical</span> Cloud Systems and Processes experiment is sponsored by the National Aeronautics and Space Administration (NASA) to investigate characteristics of <span class="hlt">tropical</span> cyclone genesis, rapid intensification and rainfall using a three-pronged approach that emphasizes satellite information, suborbital observations and numerical model simulations. Research goals include demonstration and assessment of new technology, improvements to numerical model parameterizations, and advancements in data assimilation techniques. The field phase of the experiment was based in Costa Rica during July 2005. A fully instrumented NASA ER-2 high altitude airplane was deployed with Doppler radar, passive microwave instrumentation, lightning and electric field sensors and an airborne simulator of visible and infrared satellite sensors. Other assets brought to TCSP were a low flying uninhabited aerial vehicle, and a surface-based radiosonde network. In partnership with the Intensity Forecasting Experiment of the National Oceanic and Atmospheric Administration (NOAA) Hurricane Research Division, two NOAA P-3 aircraft instrumented with radar, passive microwave, microphysical, and dropsonde instrumentation were also deployed to Costa Rica. The field phase of TCSP was conducted in Costa Rica to take advantage of the geographically compact <span class="hlt">tropical</span> cyclone genesis region of the Eastern <span class="hlt">Pacific</span> Ocean near <span class="hlt">Central</span> America. However, the unusual 2005 hurricane season provided numerous opportunities to sample <span class="hlt">tropical</span> cyclone development and intensification in the Caribbean Sea and Gulf of Mexico as well. Development of Hurricane Dennis and <span class="hlt">Tropical</span> Storm Gert were each investigated over several days in addition to Hurricane Emily as it was close to Saffir-Simpson Category 5 intensity. An overview of the characteristics of these storms along with the pregenesis environment of <span class="hlt">Tropical</span> Storm Eugene in the Eastern <span class="hlt">Pacific</span> will be presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMOS43B1532M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMOS43B1532M"><span>Vertical eddy diffusivity as a control parameter in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Martinez Avellaneda, N.; Cornuelle, B.</p> <p>2011-12-01</p> <p>Ocean models suffer from errors in the treatment of turbulent sub-grid-scale motions responsible for mixing and energy dissipation. Unrealistic small-scale physics in models can have large-scale consequences, such as biases in the upper ocean temperature, a symptom of poorly-simulated upwelling, currents and air-sea interactions. This is of special importance in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean (TP), which is home to energetic air-sea interactions that affect global climate. It has been shown in a number of studies that the simulated ENSO variability is highly dependent on the state of the ocean (e.g.: background mixing). Moreover, the magnitude of the vertical numerical diffusion is of primary importance in properly reproducing the <span class="hlt">Pacific</span> equatorial thermocline. This work is part of a NASA-funded project to estimate the space- and time-varying ocean mixing coefficients in an eddy-permitting (1/3dgr) model of the TP to obtain an improved estimate of its time-varying circulation and its underlying dynamics. While an estimation procedure for the TP (26dgr S - 30dgr N) in underway using the MIT general circulation model, complementary adjoint-based sensitivity studies have been carried out for the starting ocean state from Forget (2010). This analysis aids the interpretation of the estimated mixing coefficients and possible error compensation. The focus of the sensitivity tests is the Equatorial Undercurrent and sub-thermocline jets (i.e., Tsuchiya Jets), which have been thought to have strong dependence on vertical diffusivity and should provide checks on the estimated mixing parameters. In order to build intuition for the vertical diffusivity adjoint results in the TP, adjoint and forward perturbed simulations were carried out for an idealized sharp thermocline in a rectangular domain.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMPP23A2275R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMPP23A2275R"><span>Late Holocene Sea Surface Temperature Trends in the Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rustic, G. T.; Koutavas, A.; Marchitto, T. M., Jr.</p> <p>2015-12-01</p> <p>The Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> (ETP) is a highly dynamic ocean region capable of exerting influencing on global climate as illustrated by the El Niño-Southern Oscillation (ENSO). The sea surface temperature (SST) history of this region in past millennia is poorly constrained due to the lack of in situ records with appropriate resolution. Here we present a ~2700 year sub-centennially resolved SST reconstruction from Mg/Ca ratios of the planktonic foraminifer Globigerinoides ruber from Galápagos sediments. The ETP SST record exhibits a long-term cooling trend of over 0.2°C/ky that is similar to Northern Hemisphere multi-proxy temperature trends suggesting a common origin, likely due to insolation forcing. The ETP remains in-phase with Northern Hemisphere climate records through the warm Roman Climate Optimum (~0-400CE), cooler Dark Ages Cold Period (~450-850CE), and through the peak warming of the Medieval Climate Anomaly (900-1150 CE) when SST is within error of modern. Following peak MCA, the ETP cooled rapidly and then rebounded at ~1500 CE during the coldest portion of the Little Ice Age. Overall the data suggest an out-of-phase relationship during much of the last millennium, which we attribute to dynamical adjustments consistent with the "dynamical ocean thermostat" mechanism. Further evidence for these dynamical adjustments comes from reconstructions of the east-west zonal SST gradient using existing Mg/Ca SST reconstructions from the western <span class="hlt">Pacific</span> warm pool. The last millennium has been the most dynamic period over the past 2700 years, with significant (~1 °C) SST variability in the ETP and modulation of the zonal gradient. A combination of dynamical and thermodynamic mechanisms are invoked to explain the region's complex SST history.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/1203854-quantifying-diurnal-cloud-radiative-effects-cloud-type-tropical-western-pacific','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/1203854-quantifying-diurnal-cloud-radiative-effects-cloud-type-tropical-western-pacific"><span>Quantifying Diurnal Cloud Radiative Effects by Cloud Type in the <span class="hlt">Tropical</span> Western <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Burleyson, Casey D.; Long, Charles N.; Comstock, Jennifer M.</p> <p>2015-06-01</p> <p>Cloud radiative effects are examined using long-term datasets collected at the three Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facilities in the <span class="hlt">tropical</span> western <span class="hlt">Pacific</span>. We quantify the surface radiation budget, cloud populations, and cloud radiative effects by partitioning the data by cloud type, time of day, and as a function of large scale modes of variability such as El Niño Southern Oscillation (ENSO) phase and wet/dry seasons at Darwin. The novel facet of our analysis is that we break aggregate cloud radiative effects down by cloud type across the diurnal cycle. The Nauru cloud populations andmore » subsequently the surface radiation budget are strongly impacted by ENSO variability whereas the cloud populations over Manus only shift slightly in response to changes in ENSO phase. The Darwin site exhibits large seasonal monsoon related variations. We show that while deeper convective clouds have a strong conditional influence on the radiation reaching the surface, their limited frequency reduces their aggregate radiative impact. The largest source of shortwave cloud radiative effects at all three sites comes from low clouds. We use the observations to demonstrate that potential model biases in the amplitude of the diurnal cycle and mean cloud frequency would lead to larger errors in the surface energy budget compared to biases in the timing of the diurnal cycle of cloud frequency. Our results provide solid benchmarks to evaluate model simulations of cloud radiative effects in the <span class="hlt">tropics</span>.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29662073','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29662073"><span>Global warming hiatus contributed to the increased occurrence of intense <span class="hlt">tropical</span> cyclones in the coastal regions along East Asia.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhao, Jiuwei; Zhan, Ruifen; Wang, Yuqing</p> <p>2018-04-16</p> <p>The recent global warming hiatus (GWH) was characterized by a La Niña-like cooling in the <span class="hlt">tropical</span> Eastern <span class="hlt">Pacific</span> accompanied with the Indian Ocean and the <span class="hlt">tropical</span> Atlantic Ocean warming. Here we show that the recent GWH contributed significantly to the increased occurrence of intense <span class="hlt">tropical</span> cyclones in the coastal regions along East Asia since 1998. The GWH associated sea surface temperature anomalies triggered a pair of anomalous cyclonic and anticyclonic circulations and equatorial easterly anomalies over the Northwest <span class="hlt">Pacific</span>, which favored TC genesis and intensification over the western Northwest <span class="hlt">Pacific</span> but suppressed TC genesis and intensification over the southeastern Northwest <span class="hlt">Pacific</span> due to increased vertical wind shear and anticyclonic circulation anomalies. Results from atmospheric general circulation model experiments demonstrate that the <span class="hlt">Pacific</span> La Niña-like cooling dominated the Indian Ocean and the <span class="hlt">tropical</span> Atlantic Ocean warming in contributing to the observed GWH-related anomalous atmospheric circulation over the Northwest <span class="hlt">Pacific</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.A23D0217Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.A23D0217Y"><span>Contribution of <span class="hlt">Tropical</span> Cyclones to the Interannual Variability of Baiu Precipitation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yamaura, T.; Tomita, T.</p> <p>2011-12-01</p> <p>This work examines the contribution of <span class="hlt">tropical</span> cyclones to the interannual variability of Baiu precipitation with the large-scale interannual variations in the <span class="hlt">tropics</span>, that is, the El Niño/Southern Oscillation (ENSO) and the Tropospheric Biennial Oscillation (TBO) in the Asian monsoon. The data used are the Global Precipitation Climatology Project, the Japanese 25-year Reanalysis Project/Japan Meteorological Agency Climate Data Assimilation System, and the Joint Typhoon Warning Center. The diagnosed months and the time period are June and July, and 30 years from 1979 to 2008. When the negative precipitation anomalies appear in the entire Baiu front with the cold ENSO phase, the number of <span class="hlt">tropical</span> cyclones increases around the northern part of the Philippines, and a larger-scale anomalous cyclone is formed there. <span class="hlt">Tropical</span> cyclones contribute to strengthening the anomalous cyclone. Anomalous convective activity in the anomalous cyclone excites Rossby waves that propagate northward within the low-level jet and form an anomalous anticyclone around Japan. The anomalous anticyclone decreases the Baiu precipitation. On the other hand, the number of <span class="hlt">tropical</span> cyclones decreases, and an anomalous anticyclone is set around the northern part of the Philippines, when the positive precipitation anomalies are observed in the Baiu front with the warm ENSO phase. The contribution of <span class="hlt">tropical</span> cyclones is insignificant in this phase. The warm and cold TBO phases are judged from sea surface temperature (SST) anomalies in the equatorial <span class="hlt">central</span> <span class="hlt">Pacific</span> that is different from the region for ENSO. In the cold TBO phase with the negative SST anomalies, there appear the negative precipitation anomalies around Kyushu and the positive ones to the southeast of Japan. Concurrently, an anomalous cyclone appears, and the accumulated cyclone energy estimated from the <span class="hlt">tropical</span> cyclones increases to the southeast of Japan. <span class="hlt">Tropical</span> cyclones contribute to forming the anomalous cyclone, which</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMPP51C..04G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMPP51C..04G"><span>Evidence for Shifts in Indo-<span class="hlt">Pacific</span> Hydrology over the Last Two Millennia from Indonesian Speleothems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Griffiths, M. L.; Gagan, M. K.; Drysdale, R.; Kimbrough, A. K.; Johnson, K. R.; Cole, J. E.; Zhao, J.; Ayliffe, L. K.; Hellstrom, J.; Hantoro, W. S.</p> <p>2012-12-01</p> <p>A suite of climate proxy records from the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> have provided detailed information on the behaviour of the El Niño-Southern Oscillation and associated <span class="hlt">Pacific</span> Walker Circulation (PWC) over the past millennium. However, there is still disagreement as to the precise evolution of this phenomenon, because some records have indicated that the PWC was stronger during the Medieval Climate Anomaly (MCA; ~950-1250 A.D. as defined in northern midlatitudes) and weaker during the Little Ice Age (LIA; 1450-1750 A.D.), whilst other records have suggested quite the opposite. These conflicting hypotheses are partly due to the lack of well-dated and continuous reconstructions of <span class="hlt">tropical</span> <span class="hlt">Pacific</span> climate, with the resolution capable of resolving the interannual ENSO and related decadal variability. Here we address these shortcomings by constructing an annually resolved record of Indonesian monsoon (IM) variability over the past two millennia from 18O/16O in speleothems situated within the ascending branch of the PWC in south-<span class="hlt">central</span> Indonesia. Our replicated 18O/16O record reveals that the IM was substantially weaker (relative to modern) between ~950 and 1350 A.D., and became stronger immediately thereafter between ~1350 and 1700 A.D. These patterns, which are synchronous with other proxy records from the Indo-<span class="hlt">Pacific</span>, are anti-phased with records of Indian and East Asian summer monsoon variability, suggesting that the latitudinal migration of the Intertropical Convergence Zone may have been responsible for the observed phase relationships between the northern- and southern-hemisphere low latitude regions. However, comparison of our IM record with hydrological records from the <span class="hlt">central</span>/eastern equatorial <span class="hlt">Pacific</span> shows marked anti-phasing between these regions too. Hence, zonal changes in the PWC may also explain the observed hydrologic shifts in Indonesia. Evidence for a weaker PWC during the MCA is provided by a time-space wavelet transform of our 18O/16O profile which</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1997JGR...10228489T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1997JGR...10228489T"><span>Transport of sulfur dioxide from the Asian <span class="hlt">Pacific</span> Rim to the North <span class="hlt">Pacific</span> troposphere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Thornton, Donald C.; Bandy, Alan R.; Blomquist, Byron W.; Talbot, Robert W.; Dibb, Jack E.</p> <p>1997-12-01</p> <p>The NASA <span class="hlt">Pacific</span> Exploratory Mission over the Western <span class="hlt">Pacific</span> Ocean (PEM-West B) field experiment provided an opportunity to study sulfur dioxide (SO2) in the troposphere over the western <span class="hlt">Pacific</span> Ocean from the <span class="hlt">tropics</span> to 60°N during February-March 1993. The large suite of chemical and physical measurements yielded a complex matrix in which to understand the distribution of sulfur dioxide over the western <span class="hlt">Pacific</span> region. In contrast to the late summer period of <span class="hlt">Pacific</span> Exploratory Mission-West A (PEM-West A) (1991) over this same area, SO2 showed little increase with altitude, and concentrations were much lower in the free troposphere than during the PEM-West B period. Volcanic impacts on the upper troposphere were again found as a result of deep convection in the <span class="hlt">tropics</span>. Extensive emission of SO2 from the <span class="hlt">Pacific</span> Rim land masses were primarily observed in the lower well-mixed part of the boundary layer but also in the upper part of the boundary layer. Analyses of the SO2 data with aerosol sulfate, beryllium-7, and lead-210 indicated that SO2 contributed to half or more of the observed total oxidized sulfur (SO2 plus aerosol sulfate) in free tropospheric air. The combined data set suggests that SO2 above 8.5 km is transported from the surface but with aerosol sulfate being removed more effectively than SO2. Cloud processing and rain appeared to be responsible for lower SO2 levels between 3 and 8.5 km than above or below this region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/FR-2013-09-23/pdf/2013-23106.pdf','FEDREG'); return false;" href="https://www.gpo.gov/fdsys/pkg/FR-2013-09-23/pdf/2013-23106.pdf"><span>78 FR 58240 - International Fisheries; Western and <span class="hlt">Central</span> <span class="hlt">Pacific</span> Fisheries for Highly Migratory Species...</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collection.action?collectionCode=FR">Federal Register 2010, 2011, 2012, 2013, 2014</a></p> <p></p> <p>2013-09-23</p> <p>... rule. SUMMARY: NMFS issues regulations under authority of the Western and <span class="hlt">Central</span> <span class="hlt">Pacific</span> Fisheries... has a legal and moral mandate to reduce bigeye tuna mortality immediately. Response: As stated in the... sections of this final rule, above. The analysis follows: Significant Issues Raised by Public Comments in...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19800024538','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19800024538"><span>An atlas of 1977 and 1978 GEOS-3 radar altimeter data for <span class="hlt">tropical</span> cyclone studies</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stanley, H. R.; Taylor, R. L.</p> <p>1980-01-01</p> <p>All of the GEOS 3 satellite altimeter schedule information were collected with all of the available 1977 and 1978 <span class="hlt">tropical</span> cyclone positional information. The time period covers from March 23, 1977 through Nov. 23, 1978. The geographical region includes all ocean area north of the equator divided into the following operational areas: the Atlantic area (which includes the Caribbean and Gulf of Mexico); the eastern <span class="hlt">Pacific</span> area; the <span class="hlt">central</span> and western <span class="hlt">Pacific</span> area; and the Indian Ocean area. All available source material concerning <span class="hlt">tropical</span> cyclones was collected. The date/time/location information was extracted for each disturbance. This information was compared with the GEOS 3 altimeter ON/OFF history information to determine the existence of any altimeter data close enough in both time and location to make the data potentially useful for further study (the very liberal criteria used was time less than 24 hours and location within 25 degrees). Geographic plots (cyclone versus GEOS 3 orbit track) were produced for all of the events found showing the approximate location of the cyclone and the GEOS 3 orbit traces for the full day.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_23 --> <div id="page_24" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="461"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20170011687','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20170011687"><span>Meteorological Drivers of Cold Temperatures in the Western <span class="hlt">Pacific</span> TTL</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Pfister, Leonhard; Ueyama, Rei; Jensen, Eric J.</p> <p>2017-01-01</p> <p>During the recent October 2016 aircraft sampling mission of the <span class="hlt">Tropical</span> Tropopause Layer (POSIDON -- <span class="hlt">Pacific</span> Oxidants, Sulfur, Ice, Dehydration, and cONvection), Western <span class="hlt">Pacific</span> October TTL temperatures were anomalously cold due to a combination of La Nina conditions and a very stationary convective pattern. POSIDON also had more October <span class="hlt">Tropical</span> Cyclones than typical, and <span class="hlt">tropical</span> cyclones have substantial negative TTL temperatures associated with them. This paper investigates how meteorology in the troposphere drives TTL temperatures, and how these temperatures, coupled with the circulation, produce TTL clouds. We will also compare October TTL cloud distributions in different years, examining the relationship of clouds to October temperature anomalies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeoRL..4311358B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoRL..4311358B"><span>Modes of hurricane activity variability in the eastern <span class="hlt">Pacific</span>: Implications for the 2016 season</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Boucharel, Julien; Jin, Fei-Fei; England, Matthew H.; Lin, I. I.</p> <p>2016-11-01</p> <p>A gridded product of accumulated cyclone energy (ACE) in the eastern <span class="hlt">Pacific</span> is constructed to assess the dominant mode of <span class="hlt">tropical</span> cyclone (TC) activity variability. Results of an empirical orthogonal function decomposition and regression analysis of environmental variables indicate that the two dominant modes of ACE variability (40% of the total variance) are related to different flavors of the El Niño-Southern Oscillation (ENSO). The first mode, more active during the later part of the hurricane season (September-November), is linked to the eastern <span class="hlt">Pacific</span> El Niño through the delayed oceanic control associated with the recharge-discharge mechanism. The second mode, dominant in the early months of the hurricane season, is related to the <span class="hlt">central</span> <span class="hlt">Pacific</span> El Niño mode and the associated changes in atmospheric variability. A multilinear regression forecast model of the dominant principal components of ACE variability is then constructed. The wintertime subsurface state of the eastern equatorial <span class="hlt">Pacific</span> (characterizing ENSO heat discharge), the east-west tilt of the thermocline (describing ENSO phase transition), the anomalous ocean surface conditions in the TC region in spring (portraying atmospheric changes induced by persistence of local surface anomalies), and the intraseasonal atmospheric variability in the western <span class="hlt">Pacific</span> are found to be good predictors of TC activity. Results complement NOAA's official forecast by providing additional spatial and temporal information. They indicate a more active 2016 season ( 2 times the ACE mean) with a spatial expansion into the <span class="hlt">central</span> <span class="hlt">Pacific</span> associated with the heat discharge from the 2015/2016 El Niño.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1999PhDT........13V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1999PhDT........13V"><span><span class="hlt">Tropical</span> storm interannual and interdecadal variability in an ensemble of GCM integrations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vitart, Frederic Pol.</p> <p>1999-11-01</p> <p>A T42L18 Atmospheric General Circulation Model forced by observed SSTs has been integrated for 10 years with 9 different initial conditions. An objective procedure for tracking model-generated <span class="hlt">tropical</span> storms has been applied to this ensemble. Statistical tools have been applied to the ensemble frequency, intensity and location of <span class="hlt">tropical</span> storms, leading to the conclusion that the potential predictability is particularly strong over the western North <span class="hlt">Pacific</span>, the eastern North <span class="hlt">Pacific</span> and the western North Atlantic. An EOF analysis of local SSts and a combined EOF analysis of vertical wind shear, 200 mb and 850 mb vorticity indicate that the simulated <span class="hlt">tropical</span> storm interannual variability is mostly constrained by the large scale circulation as in observations. The model simulates a realistic interannual variability of <span class="hlt">tropical</span> storms over the western North Atlantic, eastern North <span class="hlt">Pacific</span>, western North <span class="hlt">Pacific</span> and Australian basin where the model simulates a realistic large scale circulation. Several experiments with the atmospheric GCM forced by imposed SSTs demonstrate that the GCM simulates a realistic impact of ENSO on the simulated Atlantic <span class="hlt">tropical</span> storms. In addition the GCM simulates fewer <span class="hlt">tropical</span> storms over the western North Atlantic with SSTs of the 1950s than with SSTs of the 1970s in agreement with observations. <span class="hlt">Tropical</span> storms simulated with RAS and with MCA have been compared to evaluate their sensitivity to a change in cumulus parameterization. Composites of <span class="hlt">tropical</span> storm structure indicate stronger <span class="hlt">tropical</span> storms with higher warm cores with MCA. An experiment using the GFDL hurricane model and several theoretical calculations indicate that the mean state may be responsible for the difference in intensity and in the height of the warm core. With the RAS scheme, increasing the threshold which determines when convection can occur increases the <span class="hlt">tropical</span> storm frequency almost linearly. The increase of <span class="hlt">tropical</span> storm frequency seems to be linked to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUSMIN33A..09F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUSMIN33A..09F"><span>A training course on <span class="hlt">tropical</span> cyclones over the eastern <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Farfan, L. M.; Pozo, D.; Raga, G.; Romero, R.; Zavala, J.</p> <p>2008-05-01</p> <p>As part of a research project funded by the Inter-American Institute for Global Change Research (IAI), we are performing a short course based on the current understanding of <span class="hlt">tropical</span> cyclones in the eastern <span class="hlt">Pacific</span> basin. In particular, we are focused in discussing the formation and intensification off the Mexican coast. Our main goal is to train students from higher-education institutions from selected countries in Latin America. Our approach includes the review of climatological features derived from the best-track dataset issued by the National Hurricane Center. Using this dataset, we built a climatology of relevant positions and storm tracks for the base period 1970-2006. Additionally, we designed hands-on sessions in which students analyze satellite imagery from several platforms (GOES, QuikSCATT and TRMM) along with mesoscale model simulations from the WRF model. Case studies that resulted in landfall over northwestern Mexico are used; this includes Hurricanes John, Lane and Paul all of which developed during the season of 2006. So far, the course has been taught in the Atmospheric Sciences Department at the University of Buenos Aires, Argentina, and in La Paz, Mexico, with students from Mexico, Chile, Brazil, Costa Rica and Cuba.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70020423','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70020423"><span>Foods of Buller's shearwaters (Puffinus bulleri) associated with driftnet fisheries in the <span class="hlt">central</span> North <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Gould, P.; Ostrom, P.; Walker, W.</p> <p>1998-01-01</p> <p>We examined digestive tract contents and stable nitrogen isotope ratios (??15N) in breast muscles of Buller's shearwaters (Puffinus bulleri) salvaged from squid and largemesh driftnets in the <span class="hlt">central</span> North <span class="hlt">Pacific</span> Ocean. The epipelagic <span class="hlt">Pacific</span> saury (Cololabis saira) was the predominant prey, making up 71% of prey mass in digestive tracts. The remainder of the diet included small numbers of crustaceans, small fishes, and squids. The high degree of specialization in the diet seems to indicate that in the North <span class="hlt">Pacific</span>, Buller's Shearwaters usually feed at or near the water surface and rarely pursue food under water. Although these birds have been observed feeding on scraps from fishing vessels, our data suggest that offal comprises less than 10% of the diet. Stable nitrogen isotope values provided quantified information on the timing of arrival of migrants into the North <span class="hlt">Pacific</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20070037460&hterms=bateman&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dbateman','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20070037460&hterms=bateman&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dbateman"><span>Electric Field Profiles over Hurricanes, <span class="hlt">Tropical</span> Cyclones, and Thunderstorms with an Instrumented ER-2 Aircraft</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mach, Doug M.; Blakeslee, Richard J.; Bateman, Monte G.; Bailey, Jeff C.</p> <p>2007-01-01</p> <p>Over the past several years, we have flown a set of calibrated electric field meters (FMs) on the NASA high altitude ER-2 aircraft over oceanic and landbased storms in a number of locations. These included <span class="hlt">tropical</span> oceanic cyclones and hurricanes in the Caribbean and Atlantic ocean during the Third and Fourth Convection And Moisture EXperiment (CAMEX-3,1998; CAMEX-4, 2001), thunderstorms in Florida during the TExas FLorida UNderflight (TEFLUN, 1998) experiment, <span class="hlt">tropical</span> thunderstorms in Brazil during the <span class="hlt">Tropical</span> Rainfall Measuring Mission - Large Scale Biosphere-Atmosphere Experiment in Amazonia (TRMM LBA, 1999), and finally, hurricanes and <span class="hlt">tropical</span> cyclones in the Caribbean and Western <span class="hlt">Pacific</span> and thunderstorms in <span class="hlt">Central</span> America during the <span class="hlt">Tropical</span> Cloud Systems and Processes (TCSP, 2005) mission. Between these various missions we have well over 50 sorties that provide a unique insights on the different electrical environment, evolution and activity occurring in and around these various types of storms. In general, the electric fields over the <span class="hlt">tropical</span> oceanic storms and hurricanes were less than a few kilovolts per meter at the ER-2 altitude, while the lightning rates were low. Land-based thunderstorms often produced high lightning activity and correspondingly higher electric fields.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4205731','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4205731"><span>Shallow-water zoantharians (Cnidaria, Hexacorallia) from the <span class="hlt">Central</span> Indo-<span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Reimer, James D.; Poliseno, Angelo; Hoeksema, Bert W.</p> <p>2014-01-01</p> <p>Abstract Despite the <span class="hlt">Central</span> Indo-<span class="hlt">Pacific</span> (CIP) and the Indonesian Archipelago being a well-known region of coral reef biodiversity, particularly in the ‘Coral Triangle’, little published information is available on its zoantharians (Cnidaria: Hexacorallia: Zoantharia). In order to provide a basis for future research on the Indo-<span class="hlt">Pacific</span> zoantharian fauna and facilitate comparisons between more well-studied regions such as Japan and the Great Barrier Reef, this report deals with CIP zoantharian specimens in the Naturalis collection in Leiden, the Netherlands; 106 specimens were placed into 24 morpho-species and were supplemented with 88 in situ photographic records from Indonesia, the Philippines, and Papua New Guinea. At least nine morpho-species are likely to be undescribed species, indicating that the region needs more research in order to properly understand zoantharian diversity within the CIP. The Naturalis’ zoantharian specimens are listed by species, as well as all relevant collection information, and in situ images are provided to aid in future studies on zoantharians in the CIP. PMID:25349499</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.5746K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.5746K"><span>Influence of global warming on western North <span class="hlt">Pacific</span> <span class="hlt">tropical</span> cyclone intensities during 2015</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kang, Nam-Young; Yang, Se-Hwan; Elsner, James</p> <p>2017-04-01</p> <p>The climate of 2015 was characterized by a strong El Niño, global warmth, and record-setting <span class="hlt">tropical</span> cyclone (TC) intensity for western North <span class="hlt">Pacific</span> typhoons. In this study, the highest TC intensity in 32 years (1984-2015) is shown to be a consequence of above normal TC activity—following natural internal variation—and greater efficiency of intensity. The efficiency of intensity (EINT) is termed the 'blasting' effect and refers to typhoon intensification at the expense of occurrence. Statistical models show that the EINT is mostly due to the anomalous warmth in the environment as indicated by global mean sea-surface temperature. In comparison, the EINT due to El Niño is negligible. This implies that the record-setting intensity of 2015 might not have occurred without environmental warming and suggests that a year with even greater TC intensity is possible in the near future when above normal activity coincides with another record EINT due to continuous warming.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.A33Q..06B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.A33Q..06B"><span>Poleward <span class="hlt">Tropical</span> Moisture Transport and its Link to Four Sequential Extreme Weather Events over North America in October 2007</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bosart, L. F.; Cordeira, J. M.; Archambault, H. M.; Moore, B. J.</p> <p>2014-12-01</p> <p>A case of four sequentially linked extreme weather events (EWEs) during 22 - 31 October 2007 which included wildfires in southern California, cold surges in northern and eastern Mexico, widespread heavy rain in the eastern United Sates, and heavy rains in southern Mexico is presented. These EWEs were preceded by a rapid dynamically driven rapid amplification of the upper-level flow across the North <span class="hlt">Pacific</span> and North America associated with the formation of a large-amplitude Rossby wave train (RWT) through downstream baroclinic development involving multiple <span class="hlt">tropical</span> and polar disturbance interactions with the North <span class="hlt">Pacific</span> jet stream. The primary contributors to the formation of the large-amplitude RWT were two sequential upper-level polar disturbances, a diabatic Rossby vortex, western North <span class="hlt">Pacific</span> TC Kajiki, and migratory extratropical cyclones (ECs). Deep subtropical and <span class="hlt">tropical</span> moisture plumes resembling "atmospheric rivers" drawn poleward along warm conveyor belts into the warm sectors of these ECs played a critical role in further amplifying the downstream upper-level ridges based on an Eulerian analysis of negative potential vorticity advection by the irrotational wind and a Lagrangian trajectory analysis of <span class="hlt">tropical</span> and subtropical moisture sources. In particular, these atmospheric rivers extending poleward from TC Kajiki and from the subtropical eastern North <span class="hlt">Pacific</span> into the warm sectors of polar disturbance-generated ECs over the western and eastern North <span class="hlt">Pacific</span>, respectively, bolstered latent heat release and ridge building and contributed to additional upper-level flow amplification. The EWEs occurred subsequent to anticyclonic wave breaking over western North America and the concomitant downstream formation of a meridionally elongated potential vorticity streamer over the <span class="hlt">central</span> United States. The resulting high-amplitude flow pattern over North America favored the formation of the aforementioned EWEs by promoting an extensive meridional exchange</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.A12E..04R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.A12E..04R"><span>Sources of enhanced SO2 in the <span class="hlt">tropical</span> Western <span class="hlt">Pacific</span> UT/LS</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rollins, A. W.; Thornberry, T. D.; Liu, S.; Ray, E. A.; Atlas, E. L.; Navarro, M. A.; Schauffler, S.; Bui, T. V.; Gao, R. S.</p> <p>2017-12-01</p> <p>Sulfur dioxide is an important precursor to aerosols in the stratosphere. Typical mixing ratios of SO2 in the <span class="hlt">tropical</span> upper troposphere and lower stratosphere (UT/LS) are on the order of a few pptv. Convective transport of SO2 from source regions near the surface can produce local enhancements in the UT/LS of more than one order of magnitude compared to typical values. These local enhancements if sufficient in number and/or magnitude might be important for the stratospheric aerosol budget. Here we analyze three such local enhancements observed during the NASA POSIDON mission. We use back-trajectories and tracer species to demonstrate that significant SO2 in the UT/LS on different occasions originated from 1) a volcano in Papua New Guinea, 2) convection over Asia, and 3) transport of air by a typhoon. These examples that were observed on three out of ten flights indicate that significant SO2 over the Western <span class="hlt">Pacific</span> is not uncommon, and may be an important fraction of the stratospheric aerosol budget.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.A12H..01L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.A12H..01L"><span>Interdecadal Change of <span class="hlt">Tropical</span> Cyclone Genesis Controlling Parameter in Western North <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, T.</p> <p>2017-12-01</p> <p>The main environmental parameter controlling <span class="hlt">tropical</span> cyclone (TC) genesis in the western North <span class="hlt">Pacific</span> (WNP) changed in different interdecadal periods. The interannual variability of TC genesis frequency was primarily control by specific humidity in 1950-1976, sea surface temperature (SST) in 1977-1998, and vorticity in 1999-2014. A further diagnosis shows that the change of environmental specific humidity during 1950-1976 was attributed to anomalous advection of mean moisture during ENSO developing summer. The SST change during 1977-1998 was associated with circulation change during ENSO decaying summer. The change of environment vorticity was primarily related to CP-type El Niño during 1999-2014. The ultimate cause of the controlling parameter change is attributed to the change of ENSO behavior. Compared to the first period, a stronger EP-type ENSO variability in the second period leads to a stronger circulation/SST response during ENSO decaying phase. The occurrence of more frequent CP type El Niño in the third period was responsible for greater vorticity controlling in the WNP.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5016894','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5016894"><span>Hydroclimatic contrasts over Asian monsoon areas and linkages to <span class="hlt">tropical</span> <span class="hlt">Pacific</span> SSTs</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Xu, Hai; Lan, Jianghu; Sheng, Enguo; Liu, Bin; Yu, Keke; Ye, Yuanda; Shi, Zhengguo; Cheng, Peng; Wang, Xulong; Zhou, Xinying; Yeager, Kevin M.</p> <p>2016-01-01</p> <p>Knowledge of spatial and temporal hydroclimatic differences is critical in understanding climatic mechanisms. Here we show striking hydroclimatic contrasts between northern and southern parts of the eastern margin of the Tibetan Plateau (ETP), and those between East Asian summer monsoon (EASM) and Indian summer monsoon (ISM) areas during the past ~2,000 years. During the Medieval Period, and the last 100 to 200 years, the southern ETP (S-ETP) area was generally dry (on average), while the northern ETP (N-ETP) area was wet. During the Little Ice Age (LIA), hydroclimate over S-ETP areas was wet, while that over N-ETP area was dry (on average). Such hydroclimatic contrasts can be broadly extended to ISM and EASM areas. We contend that changes in sea surface temperatures (SSTs) of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> Ocean could have played important roles in producing these hydroclimatic contrasts, by forcing the north-south movement of the Intertropical Convergence Zone (ITCZ) and intensification/slowdown of Walker circulation. The results of sensitivity experiments also support such a proposition. PMID:27609356</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ESD.....9..285T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ESD.....9..285T"><span>Sensitivity of the <span class="hlt">tropical</span> climate to an interhemispheric thermal gradient: the role of <span class="hlt">tropical</span> ocean dynamics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Talento, Stefanie; Barreiro, Marcelo</p> <p>2018-03-01</p> <p>This study aims to determine the role of the <span class="hlt">tropical</span> ocean dynamics in the response of the climate to extratropical thermal forcing. We analyse and compare the outcomes of coupling an atmospheric general circulation model (AGCM) with two ocean models of different complexity. In the first configuration the AGCM is coupled with a slab ocean model while in the second a reduced gravity ocean (RGO) model is additionally coupled in the <span class="hlt">tropical</span> region. We find that the imposition of extratropical thermal forcing (warming in the Northern Hemisphere and cooling in the Southern Hemisphere with zero global mean) produces, in terms of annual means, a weaker response when the RGO is coupled, thus indicating that the <span class="hlt">tropical</span> ocean dynamics oppose the incoming remote signal. On the other hand, while the slab ocean coupling does not produce significant changes to the equatorial <span class="hlt">Pacific</span> sea surface temperature (SST) seasonal cycle, the RGO configuration generates strong warming in the <span class="hlt">central</span>-eastern basin from April to August balanced by cooling during the rest of the year, strengthening the seasonal cycle in the eastern portion of the basin. We hypothesize that such changes are possible via the dynamical effect that zonal wind stress has on the thermocline depth. We also find that the imposed extratropical pattern affects El Niño-Southern Oscillation, weakening its amplitude and low-frequency behaviour.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1999JGR...104.5865O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1999JGR...104.5865O"><span>Frequency and distribution of forest, savanna, and crop fires over <span class="hlt">tropical</span> regions during PEM-<span class="hlt">Tropics</span> A</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Olson, Jennifer R.; Baum, Bryan A.; Cahoon, Donald R.; Crawford, James H.</p> <p>1999-03-01</p> <p>Advanced very high resolution radiometer 1.1 km resolution satellite radiance data were used to locate active fires throughout much of the <span class="hlt">tropical</span> region during NASA's Global Tropospheric Experiment (GTE) <span class="hlt">Pacific</span> Exploratory Mission-<span class="hlt">Tropics</span> (PEM-<span class="hlt">Tropics</span> A) aircraft campaign, held in September and October 1996. The spatial and temporal distributions of the fires in Australia, southern Africa, and South America are presented here. The number of fires over northern Australia, <span class="hlt">central</span> Africa, and South America appeared to decrease toward the end of the mission period. Fire over eastern Australia was widespread, and temporal patterns showed a somewhat consistent amount of burning with periodic episodes of enhanced fire counts observed. At least one episode of enhanced fire counts corresponded to the passage of a frontal system which brought conditions conducive to fire to the region, with strong westerlies originating over the hot, dry interior continent. Regions that were affected by lower than normal rainfall during the previous wet season (e.g., northern Australia and southwestern Africa) showed relatively few fires during this period. This is consistent with a drought-induced decrease in vegetation and therefore a decreased availability of fuel for burning. Alternatively, a heavier than normal previous wet season along the southeastern coast of South Africa may have contributed to high fuel loading and an associated relatively heavy amount of burning compared to data from previous years.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017NatSR...741354P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017NatSR...741354P"><span>Asymmetric response of <span class="hlt">tropical</span> cyclone activity to global warming over the North Atlantic and western North <span class="hlt">Pacific</span> from CMIP5 model projections</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Park, Doo-Sun R.; Ho, Chang-Hoi; Chan, Johnny C. L.; Ha, Kyung-Ja; Kim, Hyeong-Seog; Kim, Jinwon; Kim, Joo-Hong</p> <p>2017-01-01</p> <p>Recent improvements in the theoretical understanding of the relationship between <span class="hlt">tropical</span> cyclones (TCs) and their large-scale environments have resulted in significant improvements in the skill for forecasting TC activity at daily and seasonal time-scales. However, future changes in TC activity under a warmer climate remain uncertain, particularly in terms of TC genesis locations and subsequent pathways. Applying a track-pattern-based statistical model to 22 Coupled Model Intercomparison Project Phase 5 (CMIP5) model runs for the historical period and the future period corresponding to the Representative Concentration Pathway 8.5 emissions scenarios, this study shows that in future climate conditions, TC passage frequency will decrease over the North Atlantic, particularly in the Gulf of Mexico, but will increase over the western North <span class="hlt">Pacific</span>, especially that hits Korea and Japan. Unlike previous studies based on fine-resolution models, an ensemble mean of CMIP5 models projects an increase in TC activity in the western North <span class="hlt">Pacific</span>, which is owing to enhanced subtropical deep convection and favorable dynamic conditions therein in conjunction with the expansion of the <span class="hlt">tropics</span> and vice versa for the North Atlantic. Our results suggest that North America will experience less TC landfalls, while northeast Asia will experience more TCs than in the present-day climate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28134343','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28134343"><span>Asymmetric response of <span class="hlt">tropical</span> cyclone activity to global warming over the North Atlantic and western North <span class="hlt">Pacific</span> from CMIP5 model projections.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Park, Doo-Sun R; Ho, Chang-Hoi; Chan, Johnny C L; Ha, Kyung-Ja; Kim, Hyeong-Seog; Kim, Jinwon; Kim, Joo-Hong</p> <p>2017-01-30</p> <p>Recent improvements in the theoretical understanding of the relationship between <span class="hlt">tropical</span> cyclones (TCs) and their large-scale environments have resulted in significant improvements in the skill for forecasting TC activity at daily and seasonal time-scales. However, future changes in TC activity under a warmer climate remain uncertain, particularly in terms of TC genesis locations and subsequent pathways. Applying a track-pattern-based statistical model to 22 Coupled Model Intercomparison Project Phase 5 (CMIP5) model runs for the historical period and the future period corresponding to the Representative Concentration Pathway 8.5 emissions scenarios, this study shows that in future climate conditions, TC passage frequency will decrease over the North Atlantic, particularly in the Gulf of Mexico, but will increase over the western North <span class="hlt">Pacific</span>, especially that hits Korea and Japan. Unlike previous studies based on fine-resolution models, an ensemble mean of CMIP5 models projects an increase in TC activity in the western North <span class="hlt">Pacific</span>, which is owing to enhanced subtropical deep convection and favorable dynamic conditions therein in conjunction with the expansion of the <span class="hlt">tropics</span> and vice versa for the North Atlantic. Our results suggest that North America will experience less TC landfalls, while northeast Asia will experience more TCs than in the present-day climate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19930052121&hterms=SSM&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3DSSM','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19930052121&hterms=SSM&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3DSSM"><span>Estimation and analysis of interannual variations in <span class="hlt">tropical</span> oceanic rainfall using data from SSM/I</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Berg, Wesley</p> <p>1992-01-01</p> <p>Rainfall over <span class="hlt">tropical</span> ocean regions, particularly in the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>, is estimated using Special Sensor Microwave/Imager (SSM/I) data. Instantaneous rainfall estimates are derived from brightness temperature values obtained from the satellite data using the Hughes D-Matrix algorithm. Comparisons with other satellite techniques are made to validate the SSM/I results for the <span class="hlt">tropical</span> <span class="hlt">Pacific</span>. The correlation coefficients are relatively high for the three data sets investigated, especially for the annual case.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUOS.A54B2719M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUOS.A54B2719M"><span>Analysis of the interannual variability of <span class="hlt">tropical</span> cyclones striking the California coast based on statistical downscaling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mendez, F. J.; Rueda, A.; Barnard, P.; Mori, N.; Nakajo, S.; Espejo, A.; del Jesus, M.; Diez Sierra, J.; Cofino, A. S.; Camus, P.</p> <p>2016-02-01</p> <p>Hurricanes hitting California have a very low ocurrence probability due to typically cool ocean temperature and westward tracks. However, damages associated to these improbable events would be dramatic in Southern California and understanding the oceanographic and atmospheric drivers is of paramount importance for coastal risk management for present and future climates. A statistical analysis of the historical events is very difficult due to the limited resolution of atmospheric and oceanographic forcing data available. In this work, we propose a combination of: (a) statistical downscaling methods (Espejo et al, 2015); and (b) a synthetic stochastic <span class="hlt">tropical</span> cyclone (TC) model (Nakajo et al, 2014). To build the statistical downscaling model, Y=f(X), we apply a combination of principal component analysis and the k-means classification algorithm to find representative patterns from a potential TC index derived from large-scale SST fields in Eastern <span class="hlt">Central</span> <span class="hlt">Pacific</span> (predictor X) and the associated <span class="hlt">tropical</span> cyclone ocurrence (predictand Y). SST data comes from NOAA Extended Reconstructed SST V3b providing information from 1854 to 2013 on a 2.0 degree x 2.0 degree global grid. As data for the historical occurrence and paths of <span class="hlt">tropical</span> cycloneas are scarce, we apply a stochastic TC model which is based on a Monte Carlo simulation of the joint distribution of track, minimum sea level pressure and translation speed of the historical events in the Eastern <span class="hlt">Central</span> <span class="hlt">Pacific</span> Ocean. Results will show the ability of the approach to explain seasonal-to-interannual variability of the predictor X, which is clearly related to El Niño Southern Oscillation. References Espejo, A., Méndez, F.J., Diez, J., Medina, R., Al-Yahyai, S. (2015) Seasonal probabilistic forecasting of <span class="hlt">tropical</span> cyclone activity in the North Indian Ocean, Journal of Flood Risk Management, DOI: 10.1111/jfr3.12197 Nakajo, S., N. Mori, T. Yasuda, and H. Mase (2014) Global Stochastic <span class="hlt">Tropical</span> Cyclone Model Based on</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016E%26PSL.446...45Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016E%26PSL.446...45Y"><span>Co-evolution of monsoonal precipitation in East Asia and the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> ENSO system since 2.36 Ma: New insights from high-resolution clay mineral records in the West Philippine Sea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yu, Zhaojie; Wan, Shiming; Colin, Christophe; Yan, Hong; Bonneau, Lucile; Liu, Zhifei; Song, Lina; Sun, Hanjie; Xu, Zhaokai; Jiang, Xuejun; Li, Anchun; Li, Tiegang</p> <p>2016-07-01</p> <p>Clay mineralogical analysis and scanning electron microscope (SEM) analysis were performed on deep-sea sediments cored on the Benham Rise (core MD06-3050) in order to reconstruct long-term evolution of East Asian Summer Monsoon (EASM) rainfall in the period since 2.36 Ma. Clay mineralogical variations are due to changes in the ratios of smectite, which derive from weathering of volcanic rocks in Luzon Island during intervals of intensive monsoon rainfall, and illite- and chlorite-rich dusts, which are transported from East Asia by winds associated with the East Asian Winter Monsoon (EAWM). Since Luzon is the main source of smectite to the Benham Rise, long-term consistent variations in the smectite/(illite + chlorite) ratio in core MD06-3050 as well as ODP site 1146 in the Northern South China Sea suggest that minor contributions of eolian dust played a role in the variability of this mineralogical ratio and indicate strengthening EASM precipitation in SE Asia during time intervals from 2360 to 1900 kyr, 1200 to 600 kyr, and after 200 kyr. The EASM rainfall record displays a 30 kyr periodicity suggesting the influence of El Niño-Southern Oscillation (ENSO). These intervals of rainfall intensification on Luzon Island are coeval with a reduction in precipitation over <span class="hlt">central</span> China and an increase in zonal SST gradient in the equatorial <span class="hlt">Pacific</span> Ocean, implying a reinforcement of La Niña-like conditions. In contrast, periods of reduced rainfall on Luzon Island are associated with higher precipitation in <span class="hlt">central</span> China and a weakening zonal SST gradient in the equatorial <span class="hlt">Pacific</span> Ocean, thereby suggesting the development of dominant El Niño-like conditions. Our study, therefore, highlights for the first time a long-term temporal and spatial co-evolution of monsoonal precipitation in East Asia and of the <span class="hlt">tropical</span> <span class="hlt">Pacific</span> ENSO system over the past 2.36 Ma.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19900047965&hterms=Phytoplankton&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3DPhytoplankton','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19900047965&hterms=Phytoplankton&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3DPhytoplankton"><span>Sources of variability in satellite-derived estimates of phytoplankton production in the eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Banse, Karl; Yong, Marina</p> <p>1990-01-01</p> <p>As a proxy for satellite CZCS observations and concurrent measurements of primary production rates, data from 138 stations occupied seasonally during 1967-1968 in the offshore eastern <span class="hlt">tropical</span> <span class="hlt">Pacific</span> were analyzed in terms of six temporal groups and our current regimes. Multiple linear regressions on column production Pt show that simulated satellite pigment is generally weakly correlated, but sometimes not correlated with Pt, and that incident irradiance, sea surface temperature, nitrate, transparency, and depths of mixed layer or nitracline assume little or no importance. After a proxy for the light-saturated chlorophyll-specific photosynthetic rate P(max) is added, the coefficient of determination ranges from 0.55 to 0.91 (median of 0.85) for the 10 cases. In stepwise multiple linear regressions the P(max) proxy is the best predictor for Pt.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_24 --> <div id="page_25" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="481"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29321624','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29321624"><span>Strong trans-<span class="hlt">Pacific</span> break and local conservation units in the Galapagos shark (Carcharhinus galapagensis) revealed by genome-wide cytonuclear markers.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Pazmiño, Diana A; Maes, Gregory E; Green, Madeline E; Simpfendorfer, Colin A; Hoyos-Padilla, E Mauricio; Duffy, Clinton J A; Meyer, Carl G; Kerwath, Sven E; Salinas-de-León, Pelayo; van Herwerden, Lynne</p> <p>2018-05-01</p> <p>The application of genome-wide cytonuclear molecular data to identify management and adaptive units at various spatio-temporal levels is particularly important for overharvested large predatory organisms, often characterized by smaller, localized populations. Despite being "near threatened", current understanding of habitat use and population structure of Carcharhinus galapagensis is limited to specific areas within its distribution. We evaluated population structure and connectivity across the <span class="hlt">Pacific</span> Ocean using genome-wide single-nucleotide polymorphisms (~7200 SNPs) and mitochondrial control region sequences (945 bp) for 229 individuals. Neutral SNPs defined at least two genetically discrete geographic groups: an East <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> (Mexico, east and west Galapagos Islands), and another <span class="hlt">central</span>-west <span class="hlt">Pacific</span> (Lord Howe Island, Middleton Reef, Norfolk Island, Elizabeth Reef, Kermadec, Hawaii and Southern Africa). More fine-grade population structure was suggested using outlier SNPs: west <span class="hlt">Pacific</span>, Hawaii, Mexico, and Galapagos. Consistently, mtDNA pairwise Φ ST defined three regional stocks: east, <span class="hlt">central</span> and west <span class="hlt">Pacific</span>. Compared to neutral SNPs (F ST = 0.023-0.035), mtDNA exhibited more divergence (Φ ST = 0.258-0.539) and high overall genetic diversity (h = 0.794 ± 0.014; π = 0.004 ± 0.000), consistent with the longstanding eastern <span class="hlt">Pacific</span> barrier between the east and <span class="hlt">central</span>-west <span class="hlt">Pacific</span>. Hawaiian and Southern African populations group within the west <span class="hlt">Pacific</span> cluster. Effective population sizes were moderate/high for east/west populations (738 and 3421, respectively). Insights into the biology, connectivity, genetic diversity, and population demographics informs for improved conservation of this species, by delineating three to four conservation units across their <span class="hlt">Pacific</span> distribution. Implementing such conservation management may be challenging, but is necessary to achieve long-term population resilience at basin and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27394632','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27394632"><span>A new species of Indo-<span class="hlt">Pacific</span> Modulidae (Mollusca: Caenogastropoda).</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lozouet, Pierre; Krygelmans, Anouchka</p> <p>2016-04-12</p> <p>Modulidae is a littoral cerithioid family exclusively encountered in <span class="hlt">tropical</span> and subtropical regions. It contains 12 to 15 living species (some species are not clearly delimited). Only one species is known to occur in the vast Indo-<span class="hlt">Pacific</span> region (Bouchet 2015) and two species in the eastern Atlantic. By comparison, the <span class="hlt">tropical</span> American regions are relatively rich with at least eleven living species (two or three species in the eastern <span class="hlt">Pacific</span> and nine or more in the western Atlantic), and an equivalent number or more of fossil species (Landau et al. 2014).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017APS..MARY40002H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017APS..MARY40002H"><span>Climate Change in the <span class="hlt">Pacific</span> Islands</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hamnett, Michael P.</p> <p></p> <p>Climate change have been a major concern among <span class="hlt">Pacific</span> Islanders since the late 1990s. During that period, Time Magazine featured a cover story that read: Say Goodbye to the Marshall Islands, Kiribati, and Tuvalu from sea level rise. Since that time, the South <span class="hlt">Pacific</span> Regional Environment Programme, UN and government agencies and academic researchers have been assessing the impacts of long-term climate change and seasonal to inter-annual climate variability on the <span class="hlt">Pacific</span> Islands. The consensus is that long-term climate change will result in more extreme weather and tidal events including droughts, floods, <span class="hlt">tropical</span> cyclones, coastal erosion, and salt water inundation. Extreme weather events already occur in the <span class="hlt">Pacific</span> Islands and they are patterned. El Niño Southern Oscillation (ENSO) events impact rainfall, <span class="hlt">tropical</span> cyclone and tidal patterns. In 2000, the first National Assessment of the Consequences of Climate Variability and Change concluded that long-term climate change will result in more El Niño events or a more El Niño like climate every year. The bad news is that will mean more natural disasters. The good news is that El Niño events can be predicted and people can prepare for them. The reallly bad news is that some <span class="hlt">Pacific</span> Islands are already becoming uninhabitable because of erosion of land or the loss of fresh water from droughts and salt water intrusion. Many of the most vulnerable countries already overseas populations in New Zealand, the US, or larger <span class="hlt">Pacific</span> Island countries. For some <span class="hlt">Pacific</span> Islander abandoning their home countries will be their only option.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.1840R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.1840R"><span>Nor<span class="hlt">Tropical</span> Warm Pool variability and its effects on the climate of Colombia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ricaurte Villota, Constanza; Romero-Rodriguez, Deisy; Coca-Domínguez, Oswaldo</p> <p>2015-04-01</p> <p>Much has been said about the effects of El Niño Southern Oscillation (ENSO) on oceanographic and climatic conditions in Colombia, but little is known about the influence of the Atlantic Warm Pool (AWP), which includes the gulf of Mexico, the Caribbean and the western <span class="hlt">tropical</span> North Atlantic. The AWP has been identified by some authors as an area that influences the Earth's climate, associated with anomalous summer rainfall and hurricane activity in the Atlantic. The aim of this study was to understand the variation in the AWP and its effects on the climate of Colombia. An annual average of sea surface temperature (SST) was obtained from the composition of monthly images of the Spectroradiometer Moderate Resolution Imaging Spectroradiometer (MODIS), with resolution of 4 km, for one area that comprises the marine territory of Colombia, Panama, Costa Rica both the <span class="hlt">Pacific</span> and the Caribbean, and parts of the Caribbean coast of Nicaragua, for the period between 2007 and 2013. The results suggest that warm pool is not restricted to the Caribbean, but it also covers a strip <span class="hlt">Pacific</span> bordering <span class="hlt">Central</span> America and the northern part of the Colombian coast, so it should be called the Nor-<span class="hlt">Tropical</span> Warm pool (NTWP). Within the NTWP higher SST correspond to a marine area extending about 1 degree north and south of <span class="hlt">Central</span> and out of the Colombian Caribbean coast. The NTWP also showed large interannual variability, with the years 2008 and 2009 with lower SST in average, while 2010, 2011 and 2013 years with warmer conditions, matching with greater precipitation. It was also noted that during warmer conditions (high amplitude NTWP) the cold tongue from the south <span class="hlt">Pacific</span> has less penetration on Colombian coast. Finally, the results suggest a strong influence of NTWP in climatic conditions in Colombia.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20040084065&hterms=tropospheric+ozone&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dtropospheric%2Bozone','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20040084065&hterms=tropospheric+ozone&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dtropospheric%2Bozone"><span><span class="hlt">Tropical</span> Tropospheric Ozone Climatology: Approaches Based on SHADOZ Observations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Thompson, Anne M.; Witte, Jacquelyn C.; Chatfield, Robert B.; Hudson, Robert D.; Andrade, Marcos; Coetzee, Geert J. R.; Posny, Francoise</p> <p>2004-01-01</p> <p>The SHADOZ (Southern Hemisphere Additional Ozonesondes) ozone sounding network was initiated in 1998 to improve the coverage of <span class="hlt">tropical</span> in-situ ozone measurements for satellite validation, algorithm development and related process studies. Over 2000 soundings have been archived at the <span class="hlt">central</span> website, <http://croc.gsfc.nasa.gov/shadoz>, for 12 stations that span the entire equatorial zone [Thompson et al., JGR, 108,8238, 2003]. The most striking features of tropospheric ozone profiles in SHADOZ are: (1) persistent longitudinal variability in tropospheric ozone profiles, with a 10-15 DU column-integrated difference between Atlantic and <span class="hlt">Pacific</span> sites; (2) intense short-term variability triggered by changing meteorological conditions and advection of pollution. The implications of these results for profile climatologies and trends are described along with several approaches to classifying ozone profiles: 1) Seasonal means during MAM (March-April-May) and SON (September-October-November); 2) Maxima and minima, identified through correlation of TOMS-derived TTO (<span class="hlt">tropical</span> tropospheric ozone) column depth with the sonde integrated tropospheric ozone column; and 3) Meteorological regimes, a technique that is effective in the subtropics where <span class="hlt">tropical</span> and mid-latitude conditions alternate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002AGUFMOS21C..02W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002AGUFMOS21C..02W"><span>The <span class="hlt">Tropical</span> Western Hemisphere Warm Pool</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, C.; Enfield, D. B.</p> <p>2002-12-01</p> <p>The paper describes and examines variability of the <span class="hlt">tropical</span> Western Hemisphere warm pool (WHWP) of water warmer than 28.5oC. The WHWP is the second-largest <span class="hlt">tropical</span> warm pool on Earth. Unlike the Eastern Hemisphere warm pool in the western <span class="hlt">Pacific</span>, which straddles the equator, the WHWP is entirely north of the equator. At various stages of development the WHWP extends over parts of the eastern North <span class="hlt">Pacific</span>, the Gulf of Mexico, the Caribbean, and the western <span class="hlt">tropical</span> North Atlantic. It has a large seasonal cycle and its interannual fluctuations of area and intensity are significant. Surface heat fluxes warm the WHWP through the boreal spring to an annual maximum of SST and WHWP area in the late summer/early fall, associated with eastern North <span class="hlt">Pacific</span> and Atlantic hurricane activities and rainfall from northern South America to the southern tier of the United States. Observations suggest that a positive ocean-atmosphere feedback operating through longwave radiation and associated cloudiness seems to operate in the WHWP. During winter preceding large warm pool, there is an alteration of the Walker and Hadley circulation cells that serves as a "tropospheric bridge" for transferring <span class="hlt">Pacific</span> ENSO effects to the Atlantic sector and inducing initial warming of warm pool. Associated with the warm SST anomalies is a decrease in sea level pressure anomalies and an anomalous increase in atmospheric convection and cloudiness. The increase in convective activity and cloudiness results in less net longwave radiation loss from the sea surface, which then reinforces SST anomalies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.A22F..08M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.A22F..08M"><span>Major collapse of the South <span class="hlt">Pacific</span> Convergence Zone in the future and its consequences on <span class="hlt">tropical</span> cyclones.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Menkes, C.; Dutheil, C.; Bador, M.; Lengaigne, M.; Lefèvre, J.; Jourdain, N.; Jullien, S.; Vialard, J.; Peltier, A.</p> <p>2017-12-01</p> <p>The South <span class="hlt">Pacific</span> convergence zone (SPCZ) is poorly represented in global climate models, with trademark biases such as the "double ITCZ" or related cold tongue biases. Such biases decrease our confidence in climate change projections for this region. We first show that WRF atmospheric simulations using a 1°x1° regional configuration capture the SPCZ mean state and interannual variability well over the 1980-2016 period. We then perform climate change experiments by adding the RCP8.5, 2080-2100 CMIP5 multi-model mean boundary anomalies to the present conditions. We find a 4° equatorward shift of the SPCZ west of 170°W, and associated 40% rainfall reduction in the southwestern <span class="hlt">Pacific</span>. These results strongly contrast with previous studies based on CMIP5 simulations that suggest a much weaker southwestern <span class="hlt">Pacific</span> drying ( 7%). Regional sensitivity experiments show that this CMIP5 weak response can be tracked to climatological CMIP5 SST biases, which weaken the humidity transport reduction in the south <span class="hlt">Pacific</span> in the future and result in an underestimated projected drying of the southwest <span class="hlt">Pacific</span>. Our experiments also point toward a large increase in the future SPCZ variability with increased frequency of zonal SPCZ events. Next we explore the fate of <span class="hlt">tropical</span> cyclones by downscaling the previous models to 20 km. The seasonal and spatial distribution of TC genesis and occurrence are in good agreement with the observations albeit with weaker than observed annual numbers. Our reference simulation is able to simulate intense category 4 and 5 TCs. In the future climate, we show a drastic decrease in the number of TCs ( 75%), and the disappearance of the most intense (Cat 4-5) cyclones. Additional regional simulations using a completely different set of physical parameterizations yield very similar results for the SPCZ collapse, including the strong decrease of TC numbers ( 63%), underlining the robustness of our results.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://images.nasa.gov/#/details-s72-36293.html','SCIGOVIMAGE-NASA'); return false;" href="https://images.nasa.gov/#/details-s72-36293.html"><span>Apollo 16 spacecraft touches down in the <span class="hlt">central</span> <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="https://images.nasa.gov/">NASA Image and Video Library</a></p> <p></p> <p>1972-04-27</p> <p>S72-36293 (27 April 1972) --- The Apollo 16 Command Module (CM), with astronauts John W. Young, Thomas K. Mattingly II, and Charles M. Duke Jr. aboard, splashed down in the <span class="hlt">central</span> <span class="hlt">Pacific</span> Ocean to successfully conclude their lunar landing mission. The splashdown occurred at 290:37:06 ground elapsed time, 1:45:06 p.m. (CST) Thursday, April 27, 1972, at coordinates of 00:43.2 degrees south latitude and 156:11.4 degrees west longitude. A point approximately 215 miles southeast of Christmas Island. Later the three crewmen were picked up by a helicopter from the prime recovery ship USS Ticonderoga.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ThApC.131.1235K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ThApC.131.1235K"><span>Indian summer monsoon rainfall variability during 2014 and 2015 and associated Indo-<span class="hlt">Pacific</span> upper ocean temperature patterns</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kakatkar, Rashmi; Gnanaseelan, C.; Chowdary, J. S.; Parekh, Anant; Deepa, J. S.</p> <p>2018-02-01</p> <p>In this study, factors responsible for the deficit Indian Summer Monsoon (ISM) rainfall in 2014 and 2015 and the ability of Indian Institute of <span class="hlt">Tropical</span> Meteorology-Global Ocean Data Assimilation System (IITM-GODAS) in representing the oceanic features are examined. IITM-GODAS has been used to provide initial conditions for seasonal forecast in India during 2014 and 2015. The years 2014 and 2015 witnessed deficit ISM rainfall but were evolved from two entirely different preconditions over <span class="hlt">Pacific</span>. This raises concern over the present understanding of the role of <span class="hlt">Pacific</span> Ocean on ISM variability. Analysis reveals that the mechanisms associated with the rainfall deficit over the Indian Subcontinent are different in the two years. It is found that remote forcing in summer of 2015 due to El Niño is mostly responsible for the deficit monsoon rainfall through changes in Walker circulation and large-scale subsidence. In the case of the summer of 2014, both local circulation with anomalous anticyclone over <span class="hlt">central</span> India and intrusion of mid-latitude dry winds from north have contributed for the deficit rainfall. In addition to the above, <span class="hlt">Tropical</span> Indian Ocean (TIO) sea surface temperature (SST) and remote forcing from <span class="hlt">Pacific</span> Ocean also modulated the ISM rainfall. It is observed that <span class="hlt">Pacific</span> SST warming has extended westward in 2014, making it a basin scale warming unlike the strong El Niño year 2015. The eastern equatorial Indian Ocean is anomalously warmer than west in summer of 2014, and vice versa in 2015. These differences in SST in both <span class="hlt">tropical</span> <span class="hlt">Pacific</span> and TIO have considerable impact on ISM rainfall in 2014 and 2015. The study reveals that initializing coupled forecast models with proper upper ocean temperature over the Indo-<span class="hlt">Pacific</span> is therefore essential for improved model forecast. It is important to note that the IITM-GODAS which assimilates only array for real-time geostrophic oceanography (ARGO) temperature and salinity profiles could capture most of the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1990DSRA...37.1513L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1990DSRA...37.1513L"><span>Bacterial transformations of inorganic nitrogen in the oxygen-deficient waters of the Eastern <span class="hlt">Tropical</span> South <span class="hlt">Pacific</span> Ocean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lipschultz, F.; Wofsy, S. C.; Ward, B. B.; Codispoti, L. A.; Friedrich, G.; Elkins, J. W.</p> <p>1990-10-01</p> <p>Rates of transformations of inorganic nitrogen were measured in the low oxygen, subsurface waters (50-450 m) of the Eastern <span class="hlt">Tropical</span> South <span class="hlt">Pacific</span> during February 1985, using 15N tracer techniques. Oxygen concentrations over the entire region were in a range (O 2 < 2.5 μM) that allowed both oxidation and reduction of nitrogen to occur. A wide range of rates was observed for the lowest oxygen levels, indicating that observed oxygen concentration was not a primary factor regulating nitrogen metabolism. High values for subsurface metabolic rates correspond with high levels for surface primary production, both apparently associated with mesoscale features observed in satellite imagery and with mesoscale features of the current field. Measured rates of nitrate reduction and estimated rates of denitrification were sufficient to respire nearly all of the surface primary production that might be transported into the oxygen deficient zone. These results imply that the supply of labile organic material, especially from the surface, was more important than oxygen concentration in modulating the rates of nitrogen transformations within the low oxygen water mass of the Eastern <span class="hlt">Tropical</span> South <span class="hlt">Pacific</span>. The pattern of nitrite oxidation and nitrite reduction activities in the oxygen minimum zone supports the hypothesis ( ANDERSONet al., 1982, Deep-Sea Research, 29, 1113-1140) that nitrite, produced from nitrate reduction, can be recycled by oxidation at the interface between low and high oxygen waters. Rates for denitrification, estimated from nitrate reduction rates, were in harmony with previous estimates based on electron transport system (ETS) measurements and analysis of the nitrate deficit and water residence times. Assimilation rates of NH 4+ were substantial, providing evidence for heterotrophic bacterial growth in low oxygen waters. Ambient concentrations of ammonium were maintained at low values primarily by assimilation; ammonium oxidation was an important mechanism at</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28484637','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28484637"><span>Chance long-distance or human-mediated dispersal? How Acacia s.l. farnesiana attained its pan-<span class="hlt">tropical</span> distribution.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bell, Karen L; Rangan, Haripriya; Fernandes, Manuel M; Kull, Christian A; Murphy, Daniel J</p> <p>2017-04-01</p> <p>Acacia s.l. farnesiana , which originates from Mesoamerica, is the most widely distributed Acacia s.l. species across the <span class="hlt">tropics</span>. It is assumed that the plant was transferred across the Atlantic to southern Europe by Spanish explorers, and then spread across the Old World <span class="hlt">tropics</span> through a combination of chance long-distance and human-mediated dispersal. Our study uses genetic analysis and information from historical sources to test the relative roles of chance and human-mediated dispersal in its distribution. The results confirm the Mesoamerican origins of the plant and show three patterns of human-mediated dispersal. Samples from Spain showed greater genetic diversity than those from other Old World <span class="hlt">tropics</span>, suggesting more instances of transatlantic introductions from the Americas to that country than to other parts of Africa and Asia. Individuals from the Philippines matched a population from South <span class="hlt">Central</span> Mexico and were likely to have been direct, trans-<span class="hlt">Pacific</span> introductions. Australian samples were genetically unique, indicating that the arrival of the species in the continent was independent of these European colonial activities. This suggests the possibility of pre-European human-mediated dispersal across the <span class="hlt">Pacific</span> Ocean. These significant findings raise new questions for biogeographic studies that assume chance or transoceanic dispersal for disjunct plant distributions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5414274','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5414274"><span>Chance long-distance or human-mediated dispersal? How Acacia s.l. farnesiana attained its pan-<span class="hlt">tropical</span> distribution</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Rangan, Haripriya; Fernandes, Manuel M.; Kull, Christian A.; Murphy, Daniel J.</p> <p>2017-01-01</p> <p>Acacia s.l. farnesiana, which originates from Mesoamerica, is the most widely distributed Acacia s.l. species across the <span class="hlt">tropics</span>. It is assumed that the plant was transferred across the Atlantic to southern Europe by Spanish explorers, and then spread across the Old World <span class="hlt">tropics</span> through a combination of chance long-distance and human-mediated dispersal. Our study uses genetic analysis and information from historical sources to test the relative roles of chance and human-mediated dispersal in its distribution. The results confirm the Mesoamerican origins of the plant and show three patterns of human-mediated dispersal. Samples from Spain showed greater genetic diversity than those from other Old World <span class="hlt">tropics</span>, suggesting more instances of transatlantic introductions from the Americas to that country than to other parts of Africa and Asia. Individuals from the Philippines matched a population from South <span class="hlt">Central</span> Mexico and were likely to have been direct, trans-<span class="hlt">Pacific</span> introductions. Australian samples were genetically unique, indicating that the arrival of the species in the continent was independent of these European colonial activities. This suggests the possibility of pre-European human-mediated dispersal across the <span class="hlt">Pacific</span> Ocean. These significant findings raise new questions for biogeographic studies that assume chance or transoceanic dispersal for disjunct plant distributions. PMID:28484637</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMOS22B..08K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMOS22B..08K"><span>Coherent climate anomalies over the Indo-western <span class="hlt">Pacific</span> in post-El Niño summer</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kosaka, Y.; Xie, S. P.; DU, Y.; Hu, K.; Chowdary, J. S.; Huang, G.</p> <p>2016-12-01</p> <p>El Niño typically peaks in boreal winter, and the associated equatorial <span class="hlt">Pacific</span> sea surface temperature (SST) signal dissipates before subsequent summer. Its impact, however, outlasts until boreal summer in the Indo-western <span class="hlt">Pacific</span>, featuring basin-wide Indian Ocean warming and <span class="hlt">tropical</span> Northwestern <span class="hlt">Pacific</span> cooling accompanied by the <span class="hlt">Pacific</span>-Japan (PJ) teleconnection pattern with surface anomalous anticyclone (AAC) extending from the Philippine Sea to the northern Indian Ocean. Two formation mechanisms have been proposed for these climate anomalies in post-El Niño-Southern Oscillation (ENSO) summer. One hypothesis invokes the wind-evaporation-SST (WES) feedback in the <span class="hlt">tropical</span> Northwestern <span class="hlt">Pacific</span>, while the other points to inter-basin feedback between the Indian Ocean and <span class="hlt">tropical</span> Northwestern <span class="hlt">Pacific</span>. Based on a coupled model experiment, we propose an ocean-atmosphere coupled mode that synthesizes the two mechanisms. This Indo-western <span class="hlt">Pacific</span> Ocean capacitor (IPOC) mode evolves seasonally from spring to summer under seasonal migration of background state. In spring, the WES feedback is operative in association with the <span class="hlt">tropical</span> Northwestern <span class="hlt">Pacific</span> cooling, while in summer the Indian Ocean warming and the inter-basin interaction maintains the AAC. While the IPOC mode is independent of ENSO in mechanism, ENSO can drive this mode in its decay phase. This excitation, however, has undergone substantial interdecadal modulations, depending on ENSO amplitude and persistence of Indian Ocean warming. The ENSO-IPOC correlation is high after the mid-1970s and at the beginning of the 20th century, but low in between.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.1021P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.1021P"><span>Salinity minima, water masses and surface circulation in the Eastern <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> off Mexico and surrounding areas</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Portela, Esther; Beier, Emilio; Godínez, Victor; Castro, Rubén; Desmond Barton, Eric</p> <p>2016-04-01</p> <p>The seasonal variations of the water masses and their interactions are analyzed in the <span class="hlt">Tropical</span> <span class="hlt">Pacific</span> off Mexico (TPOM) and four contiguous areas of on the basis of new extensive hydrographic database. The regional water masses intervals are redefined in terms of Absolute Salinity (SA) in g kg-1 and Conservative Temperature (Θ) according to TEOS - 10. The California Current System Water (CCSW) mass is introduced as an improved description of the former California Current Water (CCW) together with the Subarctic Water (SAW) to describe better the characteristics of the components of the California Current System. Hydrographic data, Precipitation-Evaporation balance and geostrophic currents were used to investigate the origin and seasonality of two salinity minima in the area. The shallow salinity minimum of around 33.5 g kg-1 originated in the California Current System and became saltier but less dense water as it traveled to the southeast. It can be identified as a mixture of CCSW and <span class="hlt">tropical</span> waters. The surface salinity minimum of 32 - 33 g kg-1 was seen as a sharp surface feature in the TPOM from August to November. It was produced by the arrival of <span class="hlt">tropical</span> waters from the south in combination with the net precipitation in the area during these months. This result provides new evidence of the presence of the poleward-flowing Mexican Coastal Current and, for the first time, of its seasonal pattern of variation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUSM.A21B..04H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUSM.A21B..04H"><span>The role of transients in the Mid Summer Drought over the <span class="hlt">Tropical</span> Americas</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Herrera, E.; Magaña Rueda, V.; Caetano, E.</p> <p>2013-05-01</p> <p>The Mid Summer Drought (MSD) has raised the interested of those interested in regional climate dynamics since it appears to be a unique characteristic of the <span class="hlt">tropical</span> Americas climate. The MSD corresponds to a relative minimum in summer precipitation between July and August in the Mesoamerican region. Several theories have been posed to explain its origin including the annual cycle march of the ITCZ, a teleconnection from the Asian monsoon region, or an air sea interaction process that relates the warm pools over the eastern <span class="hlt">Pacific</span> and the Caribbean Sea. However, none of them has addressed the various characteristics of the MSD described by Magaña et al (1999) and Magaña and Caetano (2005). In the present paper, the role of the transient mean flow interaction over the Caribbean Sea is explored. The Caribbean Low Level Jet (CLLJ) and the transients interact in such a way that the CLLJ reaches maximum intensity when the MSD occurs. This is a period of minimum Perturbation Kinetic Energy in the region, suggesting that a CLLJ stronger than approximately 15 m/s tends to inhibit the amplification of eddies. Transients are crucial dynamic elements to produce precipitation over the Mexico and <span class="hlt">Central</span> American region. Over the eastern <span class="hlt">Pacific</span> warm pool, <span class="hlt">tropical</span> convection and sea surface temperature are related by a sort of Clausius Clapeyron exponential equation. However, there are two branches for the relationship, one for the first maximum in <span class="hlt">tropical</span> convection during June, and a second one during September, with a relative minimum corresponding to the MSD in July - August. The most interesting aspect of such patterns is that while the June exponential curves occurs at SST larger than 28°C, the curve corresponding to September takes place at lower SSTs, suggesting that transient activity in this period is necessary to enhance <span class="hlt">tropical</span> convective activity during the latter part of the summer rains in the region. This is exactly the period when PKE increases over the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PalOc..29..143K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PalOc..29..143K"><span>Assessing millennial-scale variability during the Holocene: A perspective from the western <span class="hlt">tropical</span> <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Khider, D.; Jackson, C. S.; Stott, L. D.</p> <p>2014-03-01</p> <p>We investigate the relationship between <span class="hlt">tropical</span> <span class="hlt">Pacific</span> and Southern Ocean variability during the Holocene using the stable oxygen isotope and magnesium/calcium records of cooccurring planktonic and benthic foraminifera from a marine sediment core collected in the western equatorial <span class="hlt">Pacific</span>. The planktonic record exhibits millennial-scale sea surface temperature (SST) oscillations over the Holocene of 0.5°C while the benthic δ18Oc document 0.10‰ millennial-scale changes of Upper Circumpolar Deep Water (UCDW), a water mass which outcrops in the Southern Ocean. Solar forcing as an explanation for millennial-scale SST variability requires (1) a large climate sensitivity and (2) a long 400 year delayed response, suggesting that if solar forcing is the cause of the variability, it would need to be considerably amplified by processes within the climate system at least at the core location. We also explore the possibility that SST variability arose from volcanic forcing using a simple red noise model. Our best estimates of volcanic forcing falls short of reproducing the amplitude of observed SST variations although it produces power at low-frequency similar to that observed in the MD81 record. Although we cannot totally discount the volcanic and solar forcing hypotheses, we are left to consider that the most plausible source for Holocene millennial-scale variability lies within the climate system itself. In particular, UCDW variability coincided with deep North Atlantic changes, indicating a role for the deep ocean in Holocene millennial-scale variability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMOS53B1978W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMOS53B1978W"><span>Changes in South <span class="hlt">Pacific</span> rainfall bands in a warming climate</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Widlansky, M. J.; Timmermann, A.; Stein, K.; McGregor, S.; Schneider, N.; England, M. H.; Lengaigne, M.; Cai, W.</p> <p>2012-12-01</p> <p>The South <span class="hlt">Pacific</span> Convergence Zone (SPCZ) is the largest rainband in the Southern Hemisphere and provides most of the rainfall to Southwest <span class="hlt">Pacific</span> island nations. In spite of various modeling efforts, it remains uncertain how the SPCZ will respond to greenhouse warming. A multi-model ensemble average of 21st century climate change projections from the current-generation of Coupled General Circulation Models (CGCMs) suggests a slightly wetter Southwest <span class="hlt">Pacific</span>; however, inter-model uncertainty is greater than projected rainfall changes in the SPCZ region. Using a hierarchy of climate models we show that the uncertainty of SPCZ rainfall projections in the Southwest <span class="hlt">Pacific</span> can be explained as a result of two competing mechanisms. Higher <span class="hlt">tropical</span> sea surface temperatures (SST) lead to an overall increase of atmospheric moisture and rainfall while weaker SST gradients dynamically shift the SPCZ northeastward (see illustration) and promote summer drying in areas of the Southwest <span class="hlt">Pacific</span>, similar to the response to strong El Niño events. Based on a multi-model ensemble of 55 greenhouse warming experiments and for moderate <span class="hlt">tropical</span> warming of 2-3°C we estimate a 5% decrease of SPCZ rainfall, although uncertainty exceeds ±30% among CGCMs. For stronger <span class="hlt">tropical</span> warming, a tendency for a wetter SPCZ region is identified.; Illustration of the "warmest gets wetter" response to projected 21st century greenhouse warming. Green shading depicts observed (1982-2009) rainfall during DJF (contour interval: 2 mm/day; starting at 1 mm/day). Blue (red) contours depict warming less (more) than the <span class="hlt">tropical</span> mean (42.5°N/S) 21st century multi-model trend (contour interval: 0.2°C; starting at ±0.1°C).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017GeoRL..44.7438Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017GeoRL..44.7438Y"><span>The role of South <span class="hlt">Pacific</span> atmospheric variability in the development of different types of ENSO</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>You, Yujia; Furtado, Jason C.</p> <p>2017-07-01</p> <p>Recent advances in <span class="hlt">tropical</span> <span class="hlt">Pacific</span> climate variability have focused on understanding the development of El Niño-Southern Oscillation (ENSO) events, specifically the types or "flavors" of ENSO (i.e., <span class="hlt">central</span> versus eastern <span class="hlt">Pacific</span> events). While precursors to ENSO events exist, distinguishing the particular flavor of the expected ENSO event remains unresolved. This study offers a new look at ENSO predictability using South <span class="hlt">Pacific</span> atmospheric variability during austral winter as an indicator. The positive phase of the leading mode of South <span class="hlt">Pacific</span> sea level pressure variability, which we term the South <span class="hlt">Pacific</span> Oscillation (SPO), exhibits a meridional dipole with with a(n) (anti)cyclonic anomaly dominating the subtropics (extratropics/high latitudes). Once energized, the cyclonic anomalies in the subtropical node of the SPO weaken the southeasterly trade winds and promote the charging of the eastern equatorial <span class="hlt">Pacific</span> Ocean, giving rise to eastern <span class="hlt">Pacific</span> ENSO events. Indeed, the type of ENSO event can be determined accurately using only the magnitude and phase of the SPO during austral winter as a predictor (17 out of 23 cases). The SPO may also play a role in explaining the asymmetry of warm and cold events. Collectively, our findings present a new perspective on ENSO-South <span class="hlt">Pacific</span> interactions that can advance overall understanding of the ENSO system and enhance its predictability across multiple timescales.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70034980','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70034980"><span>Localized double-array stacking analysis of PcP: D″ and ULVZ structure beneath the Cocos plate, Mexico, <span class="hlt">central</span> <span class="hlt">Pacific</span>, and north <span class="hlt">Pacific</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Hutko, Alexander R.; Lay, Thorne; Revenaugh, Justin</p> <p>2009-01-01</p> <p>A large, high quality P-wave data set comprising short-period and broadband signals sampling four separate regions in the lowermost mantle beneath the Cocos plate, Mexico, the <span class="hlt">central</span> <span class="hlt">Pacific</span>, and the north <span class="hlt">Pacific</span> is analyzed using regional one-dimensional double-array stacking and modelling with reflectivity synthetics. A data-screening criterion retains only events with stable PcP energy in the final data stacks used for modelling and interpretation. This significantly improves the signal stacks relative to including unscreened observations, allows confident alignment on the PcP arrival and allows tight bounds to be placed on P-wave velocity structure above the core–mantle boundary (CMB). The PcP reflections under the Cocos plate are well modelled without any ultra-low velocity zone from 5 to 20°N. At latitudes from 15 to 20°N, we find evidence for two P-wave velocity discontinuities in the D″ region. The first is ∼182 km above the CMB with a δln Vp of +1.5%, near the same depth as a weaker discontinuity (<+0.5%) observed from 5 to 15°N in prior work. The other reflector is ∼454 km above the CMB, with a δln Vp of +0.4%; this appears to be a shallower continuation of the joint P- and S-wave discontinuity previously detected south of 15° N, which is presumed to be the perovskite to post-perovskite phase transition. The data stacks for paths bottoming below Mexico have PcP images that are well matched with the simple IASP91 structure, contradicting previous inferences of ULVZ presence in this region. These particular data are not very sensitive to any D″ discontinuities, and simply bound them to be <∼2%, if present. Data sampling the lowermost mantle beneath the <span class="hlt">central</span> <span class="hlt">Pacific</span> confirm the presence of a ∼15-km thick ultra-low velocity zone (ULVZ) just above the CMB, with δln Vp and δln Vs of around −3 to −4% and −4 to −8%, respectively. The ULVZ models predict previous S-wave data stacks well. The data for this region</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20010095016&hterms=temperature+variability&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dtemperature%2Bvariability','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20010095016&hterms=temperature+variability&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dtemperature%2Bvariability"><span>The Low-Frequency Variability of the <span class="hlt">Tropical</span> Atlantic Ocean</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Haekkinen, Sirpa; Mo, Kingtse C.; Koblinsky, Chester J. (Technical Monitor)</p> <p>2001-01-01</p> <p>Upper ocean temperature variability in the <span class="hlt">tropical</span> Atlantic is examined from the Comprehensive Ocean Atmosphere Data Set (COADS) as well as from an ocean model simulation forced by COADS anomalies appended to a monthly climatology. Our findings are as follows: Only the sea surface temperatures (SST) in the northern <span class="hlt">tropics</span> are driven by heat fluxes, while the southern <span class="hlt">tropical</span> variability arises from wind driven ocean circulation changes. The subsurface temperatures in the northern and southern <span class="hlt">tropics</span> are found to have a strong linkage to buoyancy forcing changes in the northern North Atlantic. Evidence for Kelvin-like boundary wave propagation from the high latitudes is presented from the model simulation. This extratropical influence is associated with wintertime North Atlantic Oscillation (NAO) forcing and manifests itself in the northern and southern <span class="hlt">tropical</span> temperature anomalies of the same sign at depth of 100-200 meters as result of a Rossby wave propagation away from the eastern boundary in the wake of the boundary wave passage. The most apparent association of the southern <span class="hlt">tropical</span> sea surface temperature anomalies (STA) arises with the anomalous cross-equatorial winds which can be related to both NAO and the remote influence from the <span class="hlt">Pacific</span> equatorial region. These teleconnections are seasonal so that the NAO impact on the <span class="hlt">tropical</span> SST is the largest it mid-winter but in spring and early summer the <span class="hlt">Pacific</span> remote influence competes with NAO. However, NAO appears to have a more substantial role than the <span class="hlt">Pacific</span> influence at low frequencies during the last 50 years. The dynamic origin of STA is indirectly confirmed from the SST-heat flux relationship using ocean model experiments which remove either anomalous wind stress forcing or atmospheric forcing anomalies contributing to heat exchange.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_25 --> <div class="footer-extlink text-muted" style="margin-bottom:1rem; text-align:center;">Some links on this page may take you to non-federal websites. Their policies may differ from this site.</div> </div><!-- container --> <footer><a id="backToTop" href="#top"> </a><nav><a id="backToTop" href="#top"> </a><ul class="links"><a id="backToTop" href="#top"> </a><li><a id="backToTop" href="#top"></a><a href="/sitemap.html">Site Map</a></li> <li><a href="/members/index.html">Members Only</a></li> <li><a href="/website-policies.html">Website Policies</a></li> <li><a href="https://doe.responsibledisclosure.com/hc/en-us" target="_blank">Vulnerability Disclosure Program</a></li> <li><a href="/contact.html">Contact Us</a></li> </ul> <div class="small">Science.gov is maintained by the U.S. Department of Energy's <a href="https://www.osti.gov/" target="_blank">Office of Scientific and Technical Information</a>, in partnership with <a href="https://www.cendi.gov/" target="_blank">CENDI</a>.</div> </nav> </footer> <script type="text/javascript"><!-- // var lastDiv = ""; function showDiv(divName) { // hide last div if (lastDiv) { document.getElementById(lastDiv).className = "hiddenDiv"; } //if value of the box is not nothing and an object with that name exists, then change the class if (divName && document.getElementById(divName)) { document.getElementById(divName).className = "visibleDiv"; lastDiv = divName; } } //--> </script> <script> /** * Function that tracks a click on an outbound link in Google Analytics. * This function takes a valid URL string as an argument, and uses that URL string * as the event label. */ var trackOutboundLink = function(url,collectionCode) { try { h = window.open(url); setTimeout(function() { ga('send', 'event', 'topic-page-click-through', collectionCode, url); }, 1000); } catch(err){} }; </script> <!-- Google Analytics --> <script> (function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){ (i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o), m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m) })(window,document,'script','//www.google-analytics.com/analytics.js','ga'); ga('create', 'UA-1122789-34', 'auto'); ga('send', 'pageview'); </script> <!-- End Google Analytics --> <script> showDiv('page_1') </script> </body> </html>