Science.gov

Sample records for extreme winter warming

  1. Impacts of extreme winter warming events on plant physiology in a sub-Arctic heath community.

    PubMed

    Bokhorst, Stef; Bjerke, Jarle W; Davey, Matthew P; Taulavuori, Kari; Taulavuori, Erja; Laine, Kari; Callaghan, Terry V; Phoenix, Gareth K

    2010-10-01

    Insulation provided by snow cover and tolerance of freezing by physiological acclimation allows Arctic plants to survive cold winter temperatures. However, both the protection mechanisms may be lost with winter climate change, especially during extreme winter warming events where loss of snow cover from snow melt results in exposure of plants to warm temperatures and then returning extreme cold in the absence of insulating snow. These events cause considerable damage to Arctic plants, but physiological responses behind such damage remain unknown. Here, we report simulations of extreme winter warming events using infrared heating lamps and soil warming cables in a sub-Arctic heathland. During these events, we measured maximum quantum yield of photosystem II (PSII), photosynthesis, respiration, bud swelling and associated bud carbohydrate changes and lipid peroxidation to identify physiological responses during and after the winter warming events in three dwarf shrub species: Empetrum hermaphroditum, Vaccinium vitis-idaea and Vaccinium myrtillus. Winter warming increased maximum quantum yield of PSII, and photosynthesis was initiated for E. hermaphroditum and V. vitis-idaea. Bud swelling, bud carbohydrate decreases and lipid peroxidation were largest for E. hermaphroditum, whereas V. myrtillus and V. vitis-idaea showed no or less strong responses. Increased physiological activity and bud swelling suggest that sub-Arctic plants can initiate spring-like development in response to a short winter warming event. Lipid peroxidation suggests that plants experience increased winter stress. The observed differences between species in physiological responses are broadly consistent with interspecific differences in damage seen in previous studies, with E. hermaphroditum and V. myrtillus tending to be most sensitive. This suggests that initiation of spring-like development may be a major driver in the damage caused by winter warming events that are predicted to become more

  2. The Extremely Warm Early Winter 2000 in Europe: What is the Forcing

    NASA Technical Reports Server (NTRS)

    Otterman, J.; Angell, J. K.; Atlas, R.; Ardizzone, J.; Demaree, G.; Jusem, J. C.; Koslowsky, D.; Terry, J.; Einaudi, Franco (Technical Monitor)

    2001-01-01

    High variability characterizes the winter climate of central Europe: interannual fluctuations in the surface-air temperature as large as 18 C over large areas are fairly common. The extraordinary early-winter 2000 in Europe appears to be a departure to an unprecedented extreme of the existing climate patterns. Such anomalous events affect agriculture, forestry, fuel consumption, etc., and thus deserve in-depth analysis. Our analysis indicates that the high anomalies of the surface-air temperature are predominantly due to the southwesterly flow from the eastern North Atlantic, with a weak contribution by southerly flow from the western Mediterranean. Backward trajectories based on the SSM/I and NCEP Reanalysis datasets traced from west-central Europe indicate that the warm air masses flowing into Europe originate in the southern North Atlantic, where the surface-air temperatures exceed by 15c or more the climatic norms in Europe for late-November or early-December. Because such large ocean-to-continent temperature differences characterize the winter conditions, we refer to this episode which started in late November as occurring in the early winter. In this season, with the sun low over the horizon in Europe, absorption of insolation by the surface has little significance. The effect of cloudiness, a corollary to the low-level maritime-air advection, is a warming by a reduction of heat loss (greenhouse effect). In contrast, in the summer, clouds, by reducing absorption of insolation, produce a cooling, effect at the surface.

  3. Snow cover and extreme winter warming events control flower abundance of some, but not all species in high arctic Svalbard.

    PubMed

    Semenchuk, Philipp R; Elberling, Bo; Cooper, Elisabeth J

    2013-08-01

    The High Arctic winter is expected to be altered through ongoing and future climate change. Winter precipitation and snow depth are projected to increase and melt out dates change accordingly. Also, snow cover and depth will play an important role in protecting plant canopy from increasingly more frequent extreme winter warming events. Flower production of many Arctic plants is dependent on melt out timing, since season length determines resource availability for flower preformation. We erected snow fences to increase snow depth and shorten growing season, and counted flowers of six species over 5 years, during which we experienced two extreme winter warming events. Most species were resistant to snow cover increase, but two species reduced flower abundance due to shortened growing seasons. Cassiope tetragona responded strongly with fewer flowers in deep snow regimes during years without extreme events, while Stellaria crassipes responded partly. Snow pack thickness determined whether winter warming events had an effect on flower abundance of some species. Warming events clearly reduced flower abundance in shallow but not in deep snow regimes of Cassiope tetragona, but only marginally for Dryas octopetala. However, the affected species were resilient and individuals did not experience any long term effects. In the case of short or cold summers, a subset of species suffered reduced reproductive success, which may affect future plant composition through possible cascading competition effects. Extreme winter warming events were shown to expose the canopy to cold winter air. The following summer most of the overwintering flower buds could not produce flowers. Thus reproductive success is reduced if this occurs in subsequent years. We conclude that snow depth influences flower abundance by altering season length and by protecting or exposing flower buds to cold winter air, but most species studied are resistant to changes. Winter warming events, often occurring

  4. Snow cover and extreme winter warming events control flower abundance of some, but not all species in high arctic Svalbard

    PubMed Central

    Semenchuk, Philipp R; Elberling, Bo; Cooper, Elisabeth J

    2013-01-01

    Abstract The High Arctic winter is expected to be altered through ongoing and future climate change. Winter precipitation and snow depth are projected to increase and melt out dates change accordingly. Also, snow cover and depth will play an important role in protecting plant canopy from increasingly more frequent extreme winter warming events. Flower production of many Arctic plants is dependent on melt out timing, since season length determines resource availability for flower preformation. We erected snow fences to increase snow depth and shorten growing season, and counted flowers of six species over 5 years, during which we experienced two extreme winter warming events. Most species were resistant to snow cover increase, but two species reduced flower abundance due to shortened growing seasons. Cassiope tetragona responded strongly with fewer flowers in deep snow regimes during years without extreme events, while Stellaria crassipes responded partly. Snow pack thickness determined whether winter warming events had an effect on flower abundance of some species. Warming events clearly reduced flower abundance in shallow but not in deep snow regimes of Cassiope tetragona, but only marginally for Dryas octopetala. However, the affected species were resilient and individuals did not experience any long term effects. In the case of short or cold summers, a subset of species suffered reduced reproductive success, which may affect future plant composition through possible cascading competition effects. Extreme winter warming events were shown to expose the canopy to cold winter air. The following summer most of the overwintering flower buds could not produce flowers. Thus reproductive success is reduced if this occurs in subsequent years. We conclude that snow depth influences flower abundance by altering season length and by protecting or exposing flower buds to cold winter air, but most species studied are resistant to changes. Winter warming events, often

  5. Impacts of warm winters and extreme rainstorms on the base consumption in a limed lake, southern Norway.

    PubMed

    Andersen, Dag O

    2003-09-01

    The chemical composition of a limed lake, the two main inlets and the outlet was monitored during a period of 3 years. The winters of 1991-1992 and 1992-1993 were unusually warm while the winter of 1993-1994 was more normal. The lake surface water was wind exposed in the warm winters and as a consequence of frequent turnovers the acid input from the catchment mixed with the whole lake water body. In the winter of 1993-1994, the lake was ice-covered for approximately 4 months. During this period the drainage water from the catchment flowed to the outlet of the lake in the upper 2-3 m of the water column and only some of the acid input was neutralised. This is compared to a complete neutralisation in the winter of 1992-1993. The in-lake loss of alkalinity during this warm winter was approximately 29 microeq/l (November-June) compared to approximately 7 microeq/l lakewater in 1993-1994. Acid drainage from the catchment induced by an extraordinary rainstorm with heavy sea-salt deposition contributed to the in-lake alkalinity consumption in spring 1993. As winter temperatures above 0 degrees C and more frequent rainstorms may be common due to expected global warming, future increased lime consumption in-lakes may be projected in acidified areas as southern Norway.

  6. Labile aluminium chemistry downstream a limestone treated lake and an acid tributary: effects of warm winters and extreme rainstorms.

    PubMed

    Andersen, Dag O

    2006-08-01

    The outlet from the limestone treated Lake Terjevann consisted mainly of well-mixed lake water (mean pH 6.1) during the ice-free seasons including the unusually warm winters of 1992 and 1993. However, during the ice-covered period acidic water (mean pH 4.8, mean inorganic aluminium (Al(i)) about 160 microg/l) from the catchment draining under the lake ice dominated. A downstream tributary was generally acid and rich in aluminium (mean pH 4.6, Al(i) about 230 microg/l). After an extreme rainstorm loaded with sea-salts cation exchange in the soil resulted in more than a doubling of the Al(i) concentration (reaching about 500 microg/l). It took 3-4 months until the Al(i) concentration returned to pre-event levels. During the ice-covered period, the acidic outlet and tributary waters resulted in acidic conditions below the confluence (pH<4.8, Al(i) about 150 microg/l) while during the ice-free periods the more neutral outlet water resulted in higher pH and lower Al(i) concentrations (pH>5.2, Al(i) about 95 microg/l). However, during the latter climatic conditions the water was most probably more harmful to fish due to hydrolysing and polymerizing aluminium. After the sea-salt event, the increased Al(i) concentration in the tributary made the zone below the confluence potentially more toxic (pH approximately 5, Al(i) approximately 250 microg/l). Expected global warming resulting in winter mean temperatures above 0 degrees C may eliminate the seasonal acidification of the outlet from limestone-treated lakes creating permanent toxic mixing zones in the confluence below acidic aluminium-rich tributaries. Besides, more frequent rainstorms as a consequence of global warming may increase the frequency of sea-salt events and the Al(i) concentrations in the mixing zones.

  7. Winter warming from large volcanic eruptions

    SciTech Connect

    Robock, A.; Mao, J.

    1992-01-01

    An examination of the Northern Hemisphere winter surface temperature patterns after the 12 largest volcanic eruptions from 1883-1992 shows warming over Eurasia and North America and cooling over the Middle East which are significant at the 95 percent level. This pattern is found in the first winter after tropical eruptions, in the first or second winter after midlatitude eruptions, and in the second winter after high latitude eruptions. The effects are independent of the hemisphere of the volcanoes. An enhanced zonal wind driven by heating of the tropical stratosphere by the volcanic aerosols is responsible for the regions of warming, while the cooling is caused by blocking of incoming sunlight.

  8. Winter warming from large volcanic eruptions

    NASA Technical Reports Server (NTRS)

    Robock, Alan; Mao, Jianping

    1992-01-01

    An examination of the Northern Hemisphere winter surface temperature patterns after the 12 largest volcanic eruptions from 1883-1992 shows warming over Eurasia and North America and cooling over the Middle East which are significant at the 95-percent level. This pattern is found in the first winter after tropical eruptions, in the first or second winter after midlatitude eruptions, and in the second winter after high latitude eruptions. The effects are independent of the hemisphere of the volcanoes. An enhanced zonal wind driven by heating of the tropical stratosphere by the volcanic aerosols is responsible for the regions of warming, while the cooling is caused by blocking of incoming sunlight.

  9. Winter warming from large volcanic eruptions

    SciTech Connect

    Robock, A.; Jianping Mao )

    1992-12-24

    An examination of the Northern Hemisphere winter surface temperature patterns after the 12 largest volcanic eruptions from 1883-1992 shows warming over Eurasia and North America and cooling over the Middle East which are significant at the 95% level. This pattern is found in the first winter after tropical eruptions, in the first or second winter after midlatitude eruptions, and in the second winter after high latitude eruptions. The effects are independent of the hemisphere of the volcanoes. An enhanced zonal wind driven by heating of the tropical stratosphere by the volcanic aerosols is responsible for the regions of warming, while the cooling is caused by blocking of incoming sunlight. 21 refs., 2 figs., 1 tab.

  10. Significant warming of the Antarctic winter troposphere.

    PubMed

    Turner, J; Lachlan-Cope, T A; Colwell, S; Marshall, G J; Connolley, W M

    2006-03-31

    We report an undocumented major warming of the Antarctic winter troposphere that is larger than any previously identified regional tropospheric warming on Earth. This result has come to light through an analysis of recently digitized and rigorously quality controlled Antarctic radiosonde observations. The data show that regional midtropospheric temperatures have increased at a statistically significant rate of 0.5 degrees to 0.7 degrees Celsius per decade over the past 30 years. Analysis of the time series of radiosonde temperatures indicates that the data are temporally homogeneous. The available data do not allow us to unambiguously assign a cause to the tropospheric warming at this stage.

  11. Winter Season Mortality: Will Climate Warming Bring Benefits?

    PubMed Central

    Kinney, Patrick L.; Schwartz, Joel; Pascal, Mathilde; Petkova, Elisaveta; Tertre, Alain Le; Medina, Sylvia; Vautard, Robert

    2015-01-01

    Extreme heat events are associated with spikes in mortality, yet death rates are on average highest during the coldest months of the year. Under the assumption that most winter excess mortality is due to cold temperature, many previous studies have concluded that winter mortality will substantially decline in a warming climate. We analyzed whether and to what extent cold temperatures are associated with excess winter mortality across multiple cities and over multiple years within individual cities, using daily temperature and mortality data from 36 US cities (1985-2006) and 3 French cities (1971-2007). Comparing across cities, we found that excess winter mortality did not depend on seasonal temperature range, and was no lower in warmer vs. colder cities, suggesting that temperature is not a key driver of winter excess mortality. Using regression models within monthly strata, we found that variability in daily mortality within cities was not strongly influenced by winter temperature. Finally we found that inadequate control for seasonality in analyses of the effects of cold temperatures led to spuriously large assumed cold effects, and erroneous attribution of winter mortality to cold temperatures. Our findings suggest that reductions in cold-related mortality under warming climate may be much smaller than some have assumed. This should be of interest to researchers and policy makers concerned with projecting future health effects of climate change and developing relevant adaptation strategies. PMID:26495037

  12. Winter season mortality: will climate warming bring benefits?

    NASA Astrophysics Data System (ADS)

    Kinney, Patrick L.; Schwartz, Joel; Pascal, Mathilde; Petkova, Elisaveta; Le Tertre, Alain; Medina, Sylvia; Vautard, Robert

    2015-06-01

    Extreme heat events are associated with spikes in mortality, yet death rates are on average highest during the coldest months of the year. Under the assumption that most winter excess mortality is due to cold temperature, many previous studies have concluded that winter mortality will substantially decline in a warming climate. We analyzed whether and to what extent cold temperatures are associated with excess winter mortality across multiple cities and over multiple years within individual cities, using daily temperature and mortality data from 36 US cities (1985-2006) and 3 French cities (1971-2007). Comparing across cities, we found that excess winter mortality did not depend on seasonal temperature range, and was no lower in warmer vs. colder cities, suggesting that temperature is not a key driver of winter excess mortality. Using regression models within monthly strata, we found that variability in daily mortality within cities was not strongly influenced by winter temperature. Finally we found that inadequate control for seasonality in analyses of the effects of cold temperatures led to spuriously large assumed cold effects, and erroneous attribution of winter mortality to cold temperatures. Our findings suggest that reductions in cold-related mortality under warming climate may be much smaller than some have assumed. This should be of interest to researchers and policy makers concerned with projecting future health effects of climate change and developing relevant adaptation strategies.

  13. The winter anomaly and sudden stratospheric warmings

    NASA Astrophysics Data System (ADS)

    Lastovicka, J.

    1984-08-01

    Large-scale stratospheric warmings are examined on the basis of 22-year measurements of radio-wave absorption at the Panska Ves observatory. It is shown that these warmings, accompanied by the reversal of wind direction in the lower thermosphere, lead not to an increase but to a decrease in the radio-wave absorption in the lower ionosphere, i.e., to the disappearance of the winter anomaly. It is concluded that the absorption decrease is connected not only with cooling in the mesopause region but also with a total change in the dynamic conditions of the lower ionosphere. The behavior of the winter anomaly in the 1979-1980 and 1981-1982 periods is examined in detail.

  14. Extreme warming in the NE Atlantic in the winter period 2002-2012 - an analysis with the regional atmospheric model COSMO-CLM and the Arctic System Reanalysis.

    NASA Astrophysics Data System (ADS)

    Kohnemann, Svenja; Heinemann, Guenther; Gutjahr, Oliver; Bromwich, David H.

    2016-04-01

    The high-resolution atmospheric model COSMO-CLM (CCLM, German Meteorological Service) is used to simulate the 2m-temperature and the boundary layer structures in the Arctic with focus on the NE Atlantic section the winter periods (Nov-Apr) between 2002 and 2015. The CCLM simulations have a horizontal resolution of 15 km for the whole Arctic. The comparable Arctic System Reanalysis data (ASR, Byrd Polar and Climate Research Center), which has been optimized for the Arctic, are available for the same time period with a horizontal resolution of 30 km. In addition, climatological data from Automatic Weather Stations (AWS) stations are used as verification. The comparison between the CCLM simulations and the ASR data shows a high agreement. Also the verification of both data sets with AWS and Era-Interim data shows a very high correlation for the air temperature. Slight differences between CCLM and ASR are recognizable in the extreme values as CCLM has the better ice information assimilated and the higher resolution during simulations. Time series of monthly mean based 2m-temperature indicate an enormous increase for the single months for the NE Atlantic and especially the region around the Siberian Island Novaya Zemlya. For example the CCLM March increase amounts up to 16 °C for the regional maximum for the period 2002-2012. The strong increase is mainly reducible to the decreasing sea ice situation in that region during the same time.

  15. Winter Storms and Extreme Cold

    MedlinePlus

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  16. Properties of stratospheric warming events during northern winter.

    NASA Astrophysics Data System (ADS)

    Maury, Pauline; Claud, Chantal; Manzini, Elisa; Hauchecorne, Alain; Keckhut, Philippe

    2015-04-01

    During wintertime the polar mid-stratosphere is characterized by the setting up of westerly winds around the pole; the so-called polar vortex. The polar vortex is one of the most variable features of the zonal-mean circulation of the earth atmosphere, due to a highly non linear interaction between planetary-scale Rossby waves and the zonal flow. Indeed, the interaction between the upward tropospheric propagating waves and the polar vortex leads to a zonal flow weakening, implying a large day to day vortex variability. In the most dramatic cases the polar vortex breaks down, the stratospheric polar flow can reverse its direction and the temperatures can rise locally by more than 50K in a span of a few days. Such phenomena are known as Sudden Stratospheric Warmings (SSWs) and constitute, since their discovery, the most impressive dynamical events in the physical climate system. There are however situations where the polar vortex does not break down, but temperatures increase dramatically. In this study, we propose a global characterization of stratospheric warmings situations based on a temperature threshold in the 50-10hPa layer, in order to assess the properties of daily stratospheric temperature variability during the northern winter. The originality of this approch consists in evaluating the wintertime positive temperature anomalies in terms of intensity and duration. We will show that there is a wide spectrum of warming types. The major SSWs are the most extreme, but there are other events that share some common properties with the major ones. Though neglected, these latter warmings may play a key role in the coupling of the stratosphere-troposphere system.

  17. Global warming and extreme storm surges

    NASA Astrophysics Data System (ADS)

    Grinsted, Aslak

    2013-04-01

    I will show empirical evidence for how global warming has changed extreme storm surge statistics for different regions in the world. Are there any detectable changes beyond what we expect from sea level rise. What does this suggest about the future of hurricane surges such as from hurricane Katrina and superstorm Sandy?

  18. Deacclimation may be crucial for winter survival of cereals under warming climate.

    PubMed

    Rapacz, Marcin; Jurczyk, Barbara; Sasal, Monika

    2017-03-01

    Climate warming can change the winter weather patterns. Warmer temperatures during winter result in a lower risk of extreme freezing events. On the other hand the predicted warm gaps during winter will decrease their freezing tolerance. Both contradict effects will affect winter survival but their resultant effect is unclear. In this paper, we demonstrate that climate warming may result in a decrease in winter survival of plants. A field study of winterhardiness of common wheat and triticale was established at 11 locations and repeated during three subsequent winters. The freezing tolerance of the plants was studied after controlled cold acclimation and de-acclimation using both plant survival analysis and chlorophyll fluorescence measurements. Cold deacclimation resistance was shown to be independent from cold acclimation ability. Further, cold deacclimation resistance appeared to be crucial for overwintering when deacclimation conditions occurred in the field. The shortening of uninterrupted cold acclimation may increase cold deacclimation efficiency, which could threaten plant survival during warmer winters. Measurements of chlorophyll fluorescence transient showed some differences triggered by freezing before and after deacclimation. We conclude that cold deacclimation resistance should be considered in the breeding of winter cereals and in future models of winter damage risk.

  19. Recent high mountain rockfalls and warm daily temperature extremes

    NASA Astrophysics Data System (ADS)

    Allen, S. K.; Huggel, C.

    2012-04-01

    temperatures in the 7 days prior to failure, (between 6 - 9°C above average), and in three of these cases, temperatures exceeded even the 99th percentile. A further 3 events occurring in this region during the longer term heatwave of 2003 similarly were also preceded by extreme daily maximum temperatures. This relationship holds for other failures analysed in the northern, and eastern regions of the central Alps. Most interestingly, the weekly temperature anomaly, and the proportion of 'extreme' days, generally decreases as the analyses are extended from 1, 2, 3 and 4 weeks out from each failure. In other words, there is a notable warming, and conditions become increasingly extreme in the lead-up to slope failure. In addition to extreme summer temperatures, our analyses points towards a possible role of unusually warm autumn and spring days influencing slope stability. A linkage between short term periods of extremely warm temperatures and rock failure may be reasonably facilitated through melt water operating within rock discontinues, processes that have recently been measured in high-mountain rock faces, and are considered to be particularly important in spring/early summer melt periods. It is not clear whether slope failures during warm autumn periods can be linked to the same processes. Rockfalls in the winter months remain rare, however, the 27 December 2011 rock avalanche at Piz Cengalo, Val Bregaglia, Switzerland (ca 2-3million m3), occurred following the warmest year on record, potentially reinforcing the role of longer term warming destabilising bedrock with permafrost at depth.

  20. Increasing Temperature Extremes during the Recent Global Warming Hiatus

    NASA Astrophysics Data System (ADS)

    Johnson, N. C.; Kosaka, Y.; Xie, S. P.

    2015-12-01

    Although the recent global warming hiatus has featured a slowdown in the annual, global mean surface air temperature trend, temperature extremes have exhibited contrasting changes, as both wintertime cold and summertime hot extremes have increased over Northern Hemisphere (NH) land from 2002-2014. To investigate the sources of NH temperature extreme variability, we use multiple linear regression analysis that includes as predictors the typical drivers of global-scale climate variability - tropical Pacific sea surface temperatures (SST), volcanic aerosols, solar variability, and the linear time trend. This analysis suggests that natural forcings, including tropical SSTs and solar variations, have contributed to the recent increase in NH winter cold extremes. The magnitude of the recent increase in summer hot extremes is only captured after including an additional SST predictor for a pattern that resembles the Atlantic Multidecadal Oscillation, which suggests the importance of Atlantic Ocean SSTs for recent increases in hot extremes. When the regression models are applied to local, grid point scales, they indicate the promise for substantial skill in seasonal predictions of extreme temperature over some NH regions. Overall, this work reveals important sources of natural variability in extreme temperature trends superimposed upon the long-term increase of hot extremes and decrease of cold extremes.

  1. Relationships between winter atmospheric circulation patterns and extreme tree growth anomalies in the Sierra Nevada

    NASA Astrophysics Data System (ADS)

    Garfin, Gregg M.

    1998-06-01

    Tree-ring data from mid-elevation (2000 m) giant sequoia (Sequoiadendron giganteum) and high elevation (3500 m) pines (Pinus balfouriana, Pinus albicaulis) were used to select extreme growth years from which temperature, precipitation and large-scale winter (November-March, NM) 500 mb circulation patterns associated with the extreme tree growth anomalies were examined.Winters preceding extreme high growth in both giant sequoia and pines are warm and wet and are characterized by anomalous low pressure in the northeastern Pacific Ocean and a tendency for southwesterly flow and advection of warm maritime air into California. For the pines, such winters exhibit a pattern of anomalous low pressure in the northern Pacific, anomalous high pressure over northwestern Canada and anomalous low pressure across the southern US. NM 500 mb heights suggest more meridional circulation during the warm and dry winters preceding extreme low growth in giant sequoia. Atmospheric circulation during these winters exhibits a persistent trough/ridge pattern between the central Pacific and the western US. Storms are deflected away from California during these winters. NM atmospheric circulation patterns associated with extreme low growth in the pines exhibit maximum westerlies north of their mean position and the tendency for enhanced ridging in the northeast Pacific, which advects cool dry air into the Sierra Nevada. As dendroclimatic reconstructions are more frequently employed in order to better understand past variability of temperature and precipitation, synoptic dendroclimatological studies such as this one provide useful insights about atmospheric circulation.

  2. Extremely Cold Winter Months in Europe (1951-2010)

    NASA Astrophysics Data System (ADS)

    Twardosz, Robert; Kossowska-Cezak, Urszula; Pełech, Sebastian

    2016-12-01

    Investigation of extreme thermal conditions is important from the perspective of global warming. Therefore, this study has been undertaken in order to determine the frequency, timing and spatial extent of extremely cold months in winter time at 60 weather stations across Europe over a sixty-year period from 1951 to 2010. Extremely cold months (ECMs) are defined as months in which the average air temperature is lower than the corresponding multi-annual average by at least 2 standard deviations. Half of all the ECMs occurred in the years 1951-1970 (33 out of 67). The lowest number of ECMs was recorded in the decade 1991-2000, but since the beginning of the 21st century, their density and territorial extent has started to increase again. The extremely cold months with ECMs of the greatest spatial extent, covering at least one third of the stations (over 20 stations), included: February 1954 (22), February 1956 (36), January 1963 (25), and January 1987 (23 stations).

  3. Models of warm and cold regimes of the winter stratosphere

    NASA Astrophysics Data System (ADS)

    Guryanov, Vladimir

    Research of fields of geopotential height, temperature, zonal and meridional wind in stratosphere was carried out using the Met Office data for winter seasons from 1991/1992 to 2006-2007. The above analyzes shows that change within season thermodynamic values at high latitudes during the winter is higher than seasonal or longitudinal change. Hence the average models of the cold periods of high latitudes and average monthly values have a limited applicability. In 1982 International Standard Organization (ISO) also acknowledged the necessity for creating of special models for "warm" and "cold" regimes of the high latitude winter stratosphere. Warm and cold stratosphere states were distinguished by the presence or absence of stratospheric warmings of variable intensity exceeding 10 hPa. Special maps and latitude-longitude cuts of mean values and mean square deviations of the geopotential height, temperature, zonal and meridional wind have been created for these regimes. Models of "warm" and "cold" regimes also included zonal harmonics with wave numbers 1 and 2 for all observed meteorological fields

  4. Changes in Extreme Warm and Cold Temperatures Associated with 20th Century Global Warming

    NASA Astrophysics Data System (ADS)

    Sardeshmukh, P. D.; Compo, G. P.; McColl, C.; Penland, C.

    2015-12-01

    Has 20thcentury global warming resulted in increases of extreme warm temperatures and decreases of extreme cold temperatures around the globe? One would certainly expect this to be so if the changes in the extreme temperature probabilities were determined only by the mean shift and not by changes in the width and/or shape of the temperature distribution. In reality, however, the latter two effects could also be important. Even ignoring changes of shape, it is easily shown that a 25% reduction of standard deviation, for example, can completely offset the effect of a mean positive shift of 0.5 standardized units on the probabilities of extreme positive values. A 25% increase of standard deviation can similarly offset the effect of the mean shift on the probabilities of extreme negative values. It is possible for such changes of standard deviation to occur in regions of large circulation and storminess changes associated with global warming. With this caveat in mind, we have investigated the change in probability of extreme weekly-averaged near-surface air temperatures, in both winter and summer, from the first half-century (1901-1950) to the last half-century (1960-2009) of the 1901 to 2009 period. We have done this using two newly available global atmospheric datasets (ERA-20C and 20CR-v2c) and large ensembles of global coupled climate model simulations of this period, plus very large ensembles of uncoupled atmospheric model simulations of our own. The results are revealing. In the tropics, the changes in the extreme warm and cold temperature probabilities are indeed generally consistent with those expected from the mean shift of the distribution. Outside the tropics, however, they are generally significantly inconsistent with the mean temperature shift, with many regions showing little or no change in the positive temperature extremes and in some instances even a decrease. In such regions, it is clear that the change in the temperature standard deviation is

  5. Passive thermal refugia provided warm water for Florida manatees during the severe winter of 2009-2010

    USGS Publications Warehouse

    Stith, B.M.; Slone, D.H.; de Wit, M.; Edwards, H.H.; Langtimm, C.A.; Swain, E.D.; Soderqvist, L.E.; Reid, J.P.

    2012-01-01

    Haloclines induced by freshwater inflow over tidal water have been identified as an important mechanism for maintaining warm water in passive thermal refugia (PTR) used by Florida manatees Trichechus manatus latirostris during winter in extreme southwestern Florida. Record-setting cold during winter 2009–2010 resulted in an unprecedented number of manatee deaths, adding to concerns that PTR may provide inadequate thermal protection during severe cold periods. Hydrological data from 2009–2010 indicate that 2 canal systems in the Ten Thousand Islands (TTI) region acted as PTR and maintained warm bottom-water temperatures, even during severe and prolonged cold periods. Aerial survey counts of live and dead manatees in TTI during the winter of 2009–2010 suggest that these PTR were effective at preventing mass mortality from hypothermia, in contrast to the nearby Everglades region, which lacks similar artificial PTR and showed high manatee carcass counts. Hydrological data from winter 2008–2009 confirmed earlier findings that without haloclines these artificial PTR may become ineffective as warm-water sites. Tidal pumping of groundwater appears to provide additional heat to bottom water during low tide cycles, but the associated thermal inversion is not observed unless salinity stratification is present. The finding that halocline-driven PTR can maintain warm water even under extreme winter conditions suggests that they may have significant potential as warm-water sites. However, availability and conflicting uses of freshwater and other management issues may make halocline-driven PTR unreliable or difficult to manage during winter.

  6. Increasing climate extremes under global warming - What is the driving force?

    NASA Astrophysics Data System (ADS)

    Yoon, J.; Wang, S. Y.; Gillies, R. R.; Hipps, L.; Kravitz, B.; Rasch, P. J.

    2015-12-01

    More climate extreme events have occurred in recent years, including the continual development of extreme drought in California, the severe cold winters in the eastern U.S. since 2014, 2015 Washington drought, and excessive wildfire events over Alaska in 2015. These have been casually attributed to global warming. However, a need for further understanding of mechanisms responsible for climate extremes is growing. In this presentation, we'll use sets of climate model simulation that designed to identify the role of the oceanic feedback in increasing climate extremes under global warming. One is with a fully coupled climate model forced by 1% ramping CO2, and the other is with an atmosphere only model forced by the same CO2 forcing. By contrasting these two, an importance of the oceanic feedback in increasing climate extremes under global warming can be diagnosed.

  7. Terra Data Confirm Warm, Dry U.S. Winter

    NASA Technical Reports Server (NTRS)

    2002-01-01

    New maps of land surface temperature and snow cover produced by NASA's Terra satellite show this year's winter was warmer than last year's, and the snow line stayed farther north than normal. The observations confirm earlier National Oceanic and Atmospheric Administration reports that the United States was unusually warm and dry this past winter. (Click to read the NASA press release and to access higher-resolution images.) For the last two years, a new sensor aboard Terra has been collecting the most detailed global measurements ever made of our world's land surface temperatures and snow cover. The Moderate-resolution Imaging Spectroradiometer (MODIS) is already giving scientists new insights into our changing planet. Average temperatures during December 2001 through February 2002 for the contiguous United States appear to have been unseasonably warm from the Rockies eastward. In the top image the coldest temperatures appear black, while dark green, blue, red, yellow, and white indicate progressively warmer temperatures. MODIS observes both land surface temperature and emissivity, which indicates how efficiently a surface absorbs and emits thermal radiation. Compared to the winter of 2000-01, temperatures throughout much of the U.S. were warmer in 2001-02. The bottom image depicts the differences on a scale from dark blue (colder this year than last) to red (warmer this year than last). A large region of warm temperatures dominated the northern Great Plains, while the area around the Great Salt Lake was a cold spot. Images courtesy Robert Simmon, NASA GSFC, based upon data courtesy Zhengming Wan, MODIS Land Science Team member at the University of California, Santa Barbara's Institute for Computational Earth System Science

  8. What caused the recent ``Warm Arctic, Cold Continents'' trend pattern in winter temperatures?

    NASA Astrophysics Data System (ADS)

    Sun, Lantao; Perlwitz, Judith; Hoerling, Martin

    2016-05-01

    The emergence of rapid Arctic warming in recent decades has coincided with unusually cold winters over Northern Hemisphere continents. It has been speculated that this "Warm Arctic, Cold Continents" trend pattern is due to sea ice loss. Here we use multiple models to examine whether such a pattern is indeed forced by sea ice loss specifically and by anthropogenic forcing in general. While we show much of Arctic amplification in surface warming to result from sea ice loss, we find that neither sea ice loss nor anthropogenic forcing overall yield trends toward colder continental temperatures. An alternate explanation of the cooling is that it represents a strong articulation of internal atmospheric variability, evidence for which is derived from model data, and physical considerations. Sea ice loss impact on weather variability over the high-latitude continents is found, however, to be characterized by reduced daily temperature variability and fewer cold extremes.

  9. Mercury concentration in phytoplankton in response to warming of an autumn - winter season.

    PubMed

    Bełdowska, Magdalena; Kobos, Justyna

    2016-08-01

    Among other climate changes in the southern Baltic, there is a tendency towards warming, especially in autumn-winter. As a result, the ice cover on the coastal zone often fails to occur. This is conducive to the thriving of phytoplankton, in which metals, including mercury, can be accumulated. The dry deposition of atmospheric Hg during heating seasons is more intense than in non-heating seasons, owing to the combustion of fossil fuels for heating purposes. This has resulted in studies into the role of phytoplankton in the introduction of Hg into the first link of trophic chain, as a function of autumn and winter warming in the coastal zone of the lagoon. The studies were conducted at two stations in the coastal zone of the southern Baltic, in the Puck Lagoon, between December 2011 and May 2013. The obtained results show that, in the estuary region, the lack of ice cover can lead to a 30% increase and during an "extremely warm" autumn and winter an increase of up to three-fold in the mean annual Hg pool in phytoplankton (mass of Hg in phytoplankton per liter of seawater). The Hg content in phytoplankton was higher when Mesodinium rubrum was prevalent in the biomass, while the proportion of dinoflagellates was small.

  10. North Siberian Permafrost reveals Holocene Arctic Winter Warming

    NASA Astrophysics Data System (ADS)

    Meyer, H.; Opel, T.; Laepple, T.; Alexander, D.; Hoffmann, K.; Werner, M.

    2014-12-01

    The Arctic climate has experienced a major warming over the past decades, which is unprecedented in the last 2000 yrs. There are, however, still major uncertainties about the temperature evolution during the Holocene. Most proxy reconstructions suggest a cooling in mid-and late Holocene (e.g. Wanner, 2008), whereas climate model simulations show only weak changes or even a moderate warming (e.g. Lohmann et al., 2013). In this study, we used ice wedges as promising permafrost climate archive studied by stable water isotope methods. Ice wedges may be identified by vertically oriented foliations, and they form by the repeated filling of winter thermal contraction cracks by snow melt water in spring. Therefore, the isotopic composition of wedge ice may be attributed to the climate conditions of the cold season (i.e. winter and spring). 42 samples of organic material enclosed in ice wedges have been directly dated by Radiocarbon methods. Here, we present the first terrestrial stable oxygen isotope record of Holocene winter temperatures in up to centennial-scale resolution based on permafrost ice wedges (Lena River Delta; Siberian Arctic). The Lena ice-wedge record shows that the recent isotopic temperatures are the highest of the past 7000 years. Despite similarities to Arctic temperature reconstructions of the last two millennia (Kaufman et al., 2009), it suggests a winter warming throughout the mid and late Holocene, opposite to most existing other proxy records (Wanner, 2008). This apparent contradiction can be explained by the seasonality of the ice-wedge genesis in combination with orbital and greenhouse gas forcing and is consistent with climate model simulations. We conclude that the present model-data mismatch might be an artefact of the summer bias of the existing proxy records and thus, our record helps to reconcile the understanding of the northern hemisphere Holocene temperature evolution. This is particular true for the Russian Arctic significantly

  11. Factors Contributing to Extremely Wet Winters in California

    NASA Astrophysics Data System (ADS)

    Jong, B. T.; Ting, M.; Seager, R.

    2015-12-01

    As California continues to battle the severe drought conditions, it becomes increasingly important to understand the atmospheric and oceanic conditions that may possible break this ongoing drought. Is a strong El Niño, such as the 2015/16 event, enough to break the drought? We examine in this study the possible factors that lead to extremely wet winters (the wettest 15%) in both Northern and Southern CA. The relationships between CA winter precipitation and sea surface temperature conditions in the Pacific, as well as atmospheric circulation are determined by using observational and reanalysis data from 1901 to 2010. One of the key features of the atmospheric circulation is the location of the low pressure anomaly, whether caused by El Niño or other factors. If the anomaly locates right off the US west coast, CA tends to be wet, and vice versa. Furthermore, the duration of the circulation anomaly seems to be crucial. During wet El Niño winters, the peak of the circulation anomaly is in the late winter, whereas, during non-wet El Niño winters, the peak of the anomaly is in the early winter. Thus, an El Niño that can last to late winter is more likely to cause an extremely wet winter in the state. The intensity of El Niño is another critical factor. In the wettest tercile late winter, a strong El Niño can bring about 200% of climatological precipitation to CA, while a weak El Niño can bring only less than 150% of climatology. In combination, only a strong El Niño that can last to late winter may make extremely wet winters very likely in CA. To explore the other factors, composites of circulation anomaly during wet & non-El Niño winters were also analyzed. The results show that a zonally propagating wave train, originating from western North Pacific, contributes to low pressure center and wet winter conditions in the state. Thus, coastal low pressure anomaly is a consistent feature for an extremely wet winters in California, but the origin of forcing can

  12. Warmer and wetter winters: characteristics and implications of an extreme weather event in the High Arctic

    NASA Astrophysics Data System (ADS)

    Hansen, Brage B.; Isaksen, Ketil; Benestad, Rasmus E.; Kohler, Jack; Pedersen, Åshild Ø.; Loe, Leif E.; Coulson, Stephen J.; Larsen, Jan Otto; Varpe, Øystein

    2014-11-01

    One predicted consequence of global warming is an increased frequency of extreme weather events, such as heat waves, droughts, or heavy rainfalls. In parts of the Arctic, extreme warm spells and heavy rain-on-snow (ROS) events in winter are already more frequent. How these weather events impact snow-pack and permafrost characteristics is rarely documented empirically, and the implications for wildlife and society are hence far from understood. Here we characterize and document the effects of an extreme warm spell and ROS event that occurred in High Arctic Svalbard in January-February 2012, during the polar night. In this normally cold semi-desert environment, we recorded above-zero temperatures (up to 7 °C) across the entire archipelago and record-breaking precipitation, with up to 98 mm rainfall in one day (return period of >500 years prior to this event) and 272 mm over the two-week long warm spell. These precipitation amounts are equivalent to 25 and 70% respectively of the mean annual total precipitation. The extreme event caused significant increase in permafrost temperatures down to at least 5 m depth, induced slush avalanches with resultant damage to infrastructure, and left a significant ground-ice cover (˜5-20 cm thick basal ice). The ground-ice not only affected inhabitants by closing roads and airports as well as reducing mobility and thereby tourism income, but it also led to high starvation-induced mortality in all monitored populations of the wild reindeer by blocking access to the winter food source. Based on empirical-statistical downscaling of global climate models run under the moderate RCP4.5 emission scenario, we predict strong future warming with average mid-winter temperatures even approaching 0 °C, suggesting increased frequency of ROS. This will have far-reaching implications for Arctic ecosystems and societies through the changes in snow-pack and permafrost properties.

  13. Winter extreme precipitation along the North American west coast

    NASA Astrophysics Data System (ADS)

    Warner, Michael D.

    primarily associated with thermodynamic changes related to future IWV increases due to warming. The dynamically downscaled NCEP-NCAR reanalysis-driven WRF model, run with a 36-km resolution outer domain and a 12-km nest, contains more realistic terrain than most GCMs and highlights the spatial precipitation distribution over the Pacific Northwest. Winter precipitation in the Pacific Northwest correlates well with offshore daily IVT (as high as ˜0.8) with spatial signatures indicative of frequent coastal mid-latitude cyclones impacting the coast. However, the most extreme AR events did not correlate as highly as expected with daily precipitation (as high as ˜0.4), despite ARs accounting for 8% or more of the total winter precipitation. When wind direction was taken into account, the correlations were much higher (˜0.7-0.8), indicating wind direction is an important factor when extreme precipitation occurs along the coast.

  14. Warming Arctic, weakening polar vortex and winter cooling

    NASA Astrophysics Data System (ADS)

    Alexeev, Vladimir; Esau, Igor; Outten, Stephen

    2014-05-01

    Spatiotemporal patterns of air temperature trends (1958-2012) are evaluated using reanalysis datasets and radiosonde data. Our analysis demonstrates large discrepancies between the reanalysis datasets, possibly due to differences in the data assimilation procedures as well as sparseness and inhomogeneity of high-latitude observations. A change of sign in the winter temperature trend from negative to positive in the mid- to late 1980s is documented in the upper troposphere/ lower stratosphere with a maximum over the Canadian Arctic. This change from cooling to warming tendency is associated with weakening of the stratospheric polar vortex and shift of its center toward the Siberian coast and possibly can be explained by the changes in the dynamics of the Arctic Oscillation. This pattern is likely linked to the observed multi-decadal variability in the Arctic with implications for recently observed winter cooling in Siberia and continental United States. Possible dynamical mechanisms linking the weakening of the polar vortex and weather in mid-latitudes are demonstrated in a number of model frameworks.

  15. Impact of future warming on winter chilling in Australia

    NASA Astrophysics Data System (ADS)

    Darbyshire, Rebecca; Webb, Leanne; Goodwin, Ian; Barlow, E. W. R.

    2013-05-01

    Increases in temperature as a result of anthropogenically generated greenhouse gas (GHG) emissions are likely to impact key aspects of horticultural production. The potential effect of higher temperatures on fruit and nut trees' ability to break winter dormancy, which requires exposure to winter chilling temperatures, was considered. Three chill models (the 0-7.2°C, Modified Utah, and Dynamic models) were used to investigate changes in chill accumulation at 13 sites across Australia according to localised temperature change related to 1, 2 and 3°C increases in global average temperatures. This methodology avoids reliance on outcomes of future GHG emission pathways, which vary and are likely to change. Regional impacts and rates of decline in chilling differ among the chill models, with the 0-7.2°C model indicating the greatest reduction and the Dynamic model the slowest rate of decline. Elevated and high latitude eastern Australian sites were the least affected while the three more maritime, less elevated Western Australian locations were shown to bear the greatest impact from future warming.

  16. Impact of future warming on winter chilling in Australia.

    PubMed

    Darbyshire, Rebecca; Webb, Leanne; Goodwin, Ian; Barlow, E W R

    2013-05-01

    Increases in temperature as a result of anthropogenically generated greenhouse gas (GHG) emissions are likely to impact key aspects of horticultural production. The potential effect of higher temperatures on fruit and nut trees' ability to break winter dormancy, which requires exposure to winter chilling temperatures, was considered. Three chill models (the 0-7.2°C, Modified Utah, and Dynamic models) were used to investigate changes in chill accumulation at 13 sites across Australia according to localised temperature change related to 1, 2 and 3°C increases in global average temperatures. This methodology avoids reliance on outcomes of future GHG emission pathways, which vary and are likely to change. Regional impacts and rates of decline in chilling differ among the chill models, with the 0-7.2°C model indicating the greatest reduction and the Dynamic model the slowest rate of decline. Elevated and high latitude eastern Australian sites were the least affected while the three more maritime, less elevated Western Australian locations were shown to bear the greatest impact from future warming.

  17. Snow line analysis in the Romanian Carpathians under the influence of winter warming

    NASA Astrophysics Data System (ADS)

    Micu, Dana; Cosmin Sandric, Ionut

    2013-04-01

    The Romanian Carpathians are subject to winter warming as statistically proved by station measurements over a 47 year period (1961-2007). Herein, the snow season is considered to last from the 1st of November to the 30th of April, when snowpack usually reaches the highest stability and thickness. This paper investigates the signals of winter temperature and precipitation change at 17 mountain station located above 1,000 m, as being considered the main triggering factors of large fluctuations in snow amount and duration in these mountains. Fewer snowfalls were recorded all over the Romanian Carpathians after the mid 80s and over large mountain areas (including the alpine ones) the frequency of positive temperature extremes became higher (e.g. winter heat waves). Late Fall snowfalls and snowpack onsets (mainly in mid elevation areas, located below 1,700 m) and particularly the shifts towards early Spring snowmelts (at all the sites) were statistically proved to explain the decline of snow cover duration across the Carpathians. However, the sensitivity of snow cover duration to recent winter warming is still blurred in the high elevation areas (above 2,000 m). The trends in winter climate variability observed in the Romanian Carpathians beyond 1,000 m altitude are fairly comparable to those estimated in other European mountain ranges from observational data (e.g. the Swiss Alps, the French Alps and the Tatra Mts.). In relation to the climate change signals derived from observational data provided by low density mountain meteorological network (of about 3.3 stations per km2 in the areas above 1,000 m), the paper analysis the spatial probability and evolution trends of snow line in each winter season across the Romanian Carpathians, based on Landsat satellite data (MSS, TM and ETM+), with sufficiently high spatial (30 to 60 m) and temporal resolutions (850 images), over the 1973-2011 period. The Landsat coverage was considered suitable enough to enable an objective

  18. The Rapid Arctic Warming and Its Impact on East Asian Winter Weather in Recent Decade

    NASA Astrophysics Data System (ADS)

    Kim, S. J.; Kim, B. M.; Kim, J. H.

    2015-12-01

    The Arctic is warming much more rapidly than the lower latitudes. In contrast to the rapid Arctic warming, in winters of the recent decade, the cold-air outbreaks over East Asia occur more frequently and stronger than in 1990s. By accompanying the snow over East Asia, the strong cold surges have led to a severe socio-economic impact. Such severe cold surges in recent decade over east Asia is consistent with the more dominant negative phase of the Arctic Oscillation (AO), that may be attributed by the Arctic amplification. In both observation-based reanalysis and numerical model experiments, the Arctic sea ice melting leads to the weakening of the AO polarity by reducing the meridional temperature gradient through a heat flux feedback. The Arctic warming and associated sea ice melting over the Kara-Barents area in late fall and early winter first release a lot of heat to the atmosphere from the ocean by a strong contrast in temperature and moisture and higher height anomaly is developed over the Kara/Barents and the Ural mountains The anomalous anticyclonic anomaly over the Arctic strengthen the Siberian High and at the same time the east Asian trough is developed over the western coast of the North Pacific. Through the passage between the margin of the Siberian High and east Asian tough, an extremely cold air is transported from east Siberia to east Asia for sometimes more than a week. Such a severe sold air brings about the moisture from nearby ocean, largely influencing the daily lives and economy in north East China, Korea, and Japan. The recent Arctic and associated sea ice melting is not only contributed to the local climate and weather, but also a severe weather in mid-latitudes through a modulation in polar vortex.

  19. The Rapid Arctic Warming in Recent Decade and Its Impact on Eurasia Winter Weather

    NASA Astrophysics Data System (ADS)

    Kim, Seong-Joong; Kim, Baek-Min; Kim, Joo-Hong; Jun, Sang-Yoon

    2016-04-01

    The Arctic is warming much more rapidly than the lower latitudes. In contrast to the rapid Arctic warming, in winters of the recent decade, the cold-air outbreaks over East Asia occur more frequently and stronger than in 1990s. By accompanying the snow over East Asia, the strong cold surges have led to a severe socio-economic impact. Such severe cold surges in recent decade over east Asia is consistent with the more dominant negative phase of the Arctic Oscillation (AO), that may be attributed by the Arctic amplification. In both observation-based reanalysis and numerical model experiments, the Arctic sea ice melting leads to the weakening of the AO polarity by reducing the meridional temperature gradient through a heat flux feedback. The Arctic warming and associated sea ice melting over the Kara-Barents area in late fall and early winter first release a lot of heat to the atmosphere from the ocean by a strong contrast in temperature and moisture and higher height anomaly is developed over the Kara/Barents and the Ural mountains The anomalous anticyclonic anomaly over the Arctic strengthen the Siberian High and at the same time the east Asian trough is developed over the western coast of the North Pacific. Through the passage between the margin of the Siberian High and east Asian tough, an extremely cold air is transported from east Siberia to east Asia for sometimes more than a week. Such a severe sold air brings about the moisture from nearby ocean, largely influencing the daily lives and economy in Eurasia. The recent Arctic and associated sea ice melting is not only contributed to the local climate and weather, but also a severe weather in mid-latitudes through a modulation in polar vortex.

  20. Persisting cold extremes under 21st-century warming scenarios

    SciTech Connect

    Kodra, Evan A; Steinhaeuser, Karsten J K; Ganguly, Auroop R

    2011-01-01

    Analyses of climate model simulations and observations reveal that extreme cold events are likely to persist across each land-continent even under 21st-century warming scenarios. The grid-based intensity, duration and frequency of cold extreme events are calculated annually through three indices: the coldest annual consecutive three-day average of daily maximum temperature, the annual maximum of consecutive frost days, and the total number of frost days. Nine global climate models forced with a moderate greenhouse-gas emissions scenario compares the indices over 2091 2100 versus 1991 2000. The credibility of model-simulated cold extremes is evaluated through both bias scores relative to reanalysis data in the past and multi-model agreement in the future. The number of times the value of each annual index in 2091 2100 exceeds the decadal average of the corresponding index in 1991 2000 is counted. The results indicate that intensity and duration of grid-based cold extremes, when viewed as a global total, will often be as severe as current typical conditions in many regions, but the corresponding frequency does not show this persistence. While the models agree on the projected persistence of cold extremes in terms of global counts, regionally, inter-model variability and disparity in model performance tends to dominate. Our findings suggest that, despite a general warming trend, regional preparedness for extreme cold events cannot be compromised even towards the end of the century.

  1. Increasing water cycle extremes in California and in relation to ENSO cycle under global warming

    PubMed Central

    Yoon, Jin-Ho; Wang, S-Y Simon; Gillies, Robert R.; Kravitz, Ben; Hipps, Lawrence; Rasch, Philip J.

    2015-01-01

    Since the winter of 2013–2014, California has experienced its most severe drought in recorded history, causing statewide water stress, severe economic loss and an extraordinary increase in wildfires. Identifying the effects of global warming on regional water cycle extremes, such as the ongoing drought in California, remains a challenge. Here we analyse large-ensemble and multi-model simulations that project the future of water cycle extremes in California as well as to understand those associations that pertain to changing climate oscillations under global warming. Both intense drought and excessive flooding are projected to increase by at least 50% towards the end of the twenty-first century; this projected increase in water cycle extremes is associated with a strengthened relation to El Niño and the Southern Oscillation (ENSO)—in particular, extreme El Niño and La Niña events that modulate California's climate not only through its warm and cold phases but also its precursor patterns. PMID:26487088

  2. Increasing water cycle extremes in California and in relation to ENSO cycle under global warming.

    PubMed

    Yoon, Jin-Ho; Wang, S-Y Simon; Gillies, Robert R; Kravitz, Ben; Hipps, Lawrence; Rasch, Philip J

    2015-10-21

    Since the winter of 2013-2014, California has experienced its most severe drought in recorded history, causing statewide water stress, severe economic loss and an extraordinary increase in wildfires. Identifying the effects of global warming on regional water cycle extremes, such as the ongoing drought in California, remains a challenge. Here we analyse large-ensemble and multi-model simulations that project the future of water cycle extremes in California as well as to understand those associations that pertain to changing climate oscillations under global warming. Both intense drought and excessive flooding are projected to increase by at least 50% towards the end of the twenty-first century; this projected increase in water cycle extremes is associated with a strengthened relation to El Niño and the Southern Oscillation (ENSO)--in particular, extreme El Niño and La Niña events that modulate California's climate not only through its warm and cold phases but also its precursor patterns.

  3. Change in abundance of pacific brant wintering in alaska: evidence of a climate warming effect?

    USGS Publications Warehouse

    Ward, David H.; Dau, Christian P.; Tibbitts, T. Lee; Sedinger, James S.; Anderson, Betty A.; Hines, James E.

    2009-01-01

    Winter distribution of Pacific Flyway brant (Branta bernicla nigricans) has shifted northward from lowtemperate areas to sub-Arctic areas over the last 42 years. We assessed the winter abundance and distribution of brant in Alaska to evaluate whether climate warming may be contributing to positive trends in the most northern of the wintering populations. Mean surface air temperatures during winter at the end of the Alaska Peninsula increased about 1??C between 1963 and 2004, resulting in a 23% reduction in freezing degree days and a 34% decline in the number of days when ice cover prevents birds from accessing food resources. Trends in the wintering population fluctuated with states of the Pacific Decadal Oscillation, increasing during positive (warm) phases and decreasing during negative (cold) phases, and this correlation provides support for the hypothesis that growth in the wintering population of brant in Alaska is linked to climate warming. The size of the wintering population was negatively correlated with the number of days of strong northwesterly winds in November, which suggests that the occurrence of tailwinds favorable for migration before the onset of winter was a key factor in whether brant migrated from Alaska or remained there during winter. Winter distribution of brant on the Alaska Peninsula was highly variable and influenced by ice cover, particularly at the heavily used Izembek Lagoon. Observations of previously marked brant indicated that the Alaska wintering population was composed primarily of birds originating from Arctic breeding colonies that appear to be growing. Numbers of brant in Alaska during winter will likely increase as temperatures rise and ice cover decreases at high latitudes in response to climate warming. ?? The Arctic Institute of North America.

  4. The Remarkable 2003-2004 Winter and Other Recent Warm Winters in the Arctic Stratosphere Since the Late 1990s

    NASA Technical Reports Server (NTRS)

    Manney, Gloria L.; Krueger, Kirstin; Sabutis, Joseph L.; Sena, Sara Amina; Pawson, Steven

    2004-01-01

    The 2003-2004 Arctic winter was remarkable in the 40-year record of meteorological analyses. A major warming beginning in early January 2004 led to nearly two months of vortex disruption with high-latitude easterlies in the middle to lower stratosphere. The upper stratospheric vortex broke up in late December, but began to recover by early January, and in February and March was the strongest since regular observations began in 1979. The lower stratospheric vortex broke up in late January. Comparison with two previous years, 1984-1985 and 1986-1987, with prolonged mid-winter warming periods shows unique characteristics of the 2003-2004 warming period: The length of the vortex disruption, the strong and rapid recovery in the upper stratosphere, and the slow progression of the warming from upper to lower stratosphere. January 2004 zonal mean winds in the middle and lower stratosphere were over two standard deviations below average. Examination of past variability shows that the recent frequency of major stratospheric warmings (seven in the past six years) is unprecedented. Lower stratospheric temperatures were unusually high during six of the past seven years, with five having much lower than usual potential for PSC formation and ozone loss (nearly none in 1998-1999, 2001-2002 and 2003-2004, and very little in 1997-1998 and 2000-2001). Middle and upper stratospheric temperatures, however, were unusually low during and after February. The pattern of five of the last seven years with very low PSC potential would be expected to occur randomly once every approximately 850 years. This cluster of warm winters, immediately following a period of unusually cold winters, may have important implications for possible changes in interannual variability and for determination and attribution of trends in stratospheric temperatures and ozone.

  5. Meridional heat transport at the onset of winter stratospheric warming

    NASA Technical Reports Server (NTRS)

    Conte, M.

    1981-01-01

    A continuous vertical flow of energy toward high altitude was verified. This process produced a dynamic instability of the stratospheric polar vortex. A meridional heat transport ws primed toward the north, which generated a warming trend.

  6. Variability of winter extreme precipitation in Southeast China: contributions of SST anomalies

    NASA Astrophysics Data System (ADS)

    Zhang, Ling; Sielmann, Frank; Fraedrich, Klaus; Zhu, Xiuhua; Zhi, Xiefei

    2015-11-01

    Tropical SST anomalies are among the largest drivers of circulation regime changes on interannual time scales due to its characteristic heat capacity decay time scales. The circulation anomalies associated with extreme precipitation and the corresponding atmospheric response to SST anomalies are derived from ECMWF ERA-Interim reanalysis data by employing composite analysis and lagged maximum covariance analysis. Our results show that interannual variability of extreme winter precipitation in Southeast China is in close accordance with the interannual variability of total winter precipitation. Both are associated with similar abnormal circulation regimes, but for extreme precipitation events the circulation anomalies and moisture transport channels are significantly intensified. Two main moisture transport channels are captured: one extends from the North Indian Ocean through India and the Bay of Bengal to South China, and the other from the West Pacific Ocean through Maritime Continent and South China Sea towards South China, which are related to the preceding autumn SST patterns, El Niño and the Indian Ocean dipole (IOD), respectively. El Niño (La Niña) SST anomalies induce anomalous anticyclonic (cyclonic) circulation over Philippine Sea, which is favorable (unfavorable) to warm and humid air transport to South China from the tropical West Pacific by southwesterly (northeasterly) anomalies. Under these circulations, northeasterlies of East Asian Winter Monsoon are weakened (strengthened) resulting in extreme precipitation to be more (less) frequent in Southeast China. During the positive (negative) IOD phase, abundant (reduced) moisture transport to South China from tropical regions through India and Bay of Bengal is observed due to weakened (strengthened) Walker circulations and abnormal anticyclonic (cyclonic) circulation over India, leading to a higher (lower) likelihood for extreme precipitation events in Southeast China. The underlying physical mechanisms

  7. [Effects of simulated warming on soil respiration in a cropland under winter wheat-soybean rotation].

    PubMed

    Liu, Yan; Chen, Shu-Tao; Hu, Zheng-Hua; Ren, Jing-Quan; Shen, Xiao-Shuai

    2012-12-01

    This study was aimed to investigate the effects of simulated warming on soil respiration in a cropland under winter wheat-soybean rotation. Randomized experiments were carried out in the cropland. 6 Plots were arranged and there were 2 treatments, simulated warming and control. A portable soil CO2 fluxes system (LI-8100) was used to measure soil respiration rates. Soil CO2 production rates were determined by using a Barometric Process Separation (BaPS) method. Soil temperature and soil moisture were simultaneously determined when measuring soil respiration rates. Results indicated that soil respiration rates in different treatments showed similar seasonal variability, in accordance with the variability in soil temperature. Seasonal mean soil respiration rates for simulated warming and control treatments were 3.54 and 2.49 micromol x (m2 x s)(-1), respectively, during the winter wheat growth season, while they were 4.80 and 4.14 micromol x (m2 x s)(-1), respectively, during the soybean growth season. Simulated warming significantly (P < 0.05) enhanced soil respiration during both the winter wheat and soybean growth seasons. The impact of simulated warming on soil respiration was particularly obvious during the later growth stages of winter wheat (from heading to maturity stages) and soybean (from flowing to maturity stages). Further investigations suggested that, for both the winter wheat and soybean growth seasons, the relationship between soil respiration and soil temperature could be well explained (P < 0.01) by exponential functions. The temperature sensitivity (Q10) of soil respiration in the simulated warming treatments was significantly higher than that in the control treatments. The Q10 values for the simulated warming and control treatments were 1.83 and 1.26, respectively, during the winter wheat growth season, while they were 2.85 and 1.70, respectively, during the soybean growth season. This study showed that simulated warming significantly increased

  8. The Remarkable 2003--2004 Winter and Other Recent Warm Winters in the Arctic Stratosphere Since the Late 1990s

    NASA Technical Reports Server (NTRS)

    Manney, Gloria L.; Kruger, Kirstin; Sabutis, Joseph L.; Sena, Sara Amina; Pawson, Steven

    2005-01-01

    The 2003-2004 Arctic winter was remarkable in the approximately 50-year record of meteorological analyses. A major warming beginning in early January 2004 led to nearly 2 months of vortex disruption with high-latitude easterlies in the middle to lower stratosphere. The upper stratospheric vortex broke up in late December, but began to recover by early January, and in February and March was the strongest since regular observations began in 1979. The lower stratospheric vortex broke up in late January. Comparison with 2 previous years, 1984-1985 and 1986-1987, with prolonged midwinter warming periods shows unique characteristics of the 2003-2004 warming period: The length of the vortex disruption, the strong and rapid recovery in the upper stratosphere, and the slow progression of the warming from upper to lower stratosphere. January 2004 zonal mean winds in the middle and lower stratosphere were over 2 standard deviations below average. Examination of past variability shows that the recent frequency of major stratospheric warmings (7 in the past 6 years) is unprecedented. Lower stratospheric temperatures were unusually high during 6 of the past 7 years, with 5 having much lower than usual potential for polar stratospheric cloud (PSC) formation and ozone loss (nearly none in 1998-1999, 2001-2002, and 2003-2004, and very little in 1997-1998 and 2000-2001). Middle and upper stratospheric temperatures, however, were unusually low during and after February. The pattern of 5 of the last 7 years with very low PSC potential would be expected to occur randomly once every 850 years. This cluster of warm winters, immediately following a period of unusually cold winters, may have important implications for possible changes in interannual variability and for determination and attribution of trends in stratospheric temperatures and ozone.

  9. Analysis of extreme summers and prior late winter/spring conditions in central Europe

    NASA Astrophysics Data System (ADS)

    Träger-Chatterjee, C.; Müller, R. W.; Bendix, J.

    2013-05-01

    Drought and heat waves during summer in mid-latitudes are a serious threat to human health and agriculture and have negative impacts on the infrastructure, such as problems in energy supply. The appearance of such extreme events is expected to increase with the progress of global warming. A better understanding of the development of extremely hot and dry summers and the identification of possible precursors could help improve existing seasonal forecasts in this regard, and could possibly lead to the development of early warning methods. The development of extremely hot and dry summer seasons in central Europe is attributed to a combined effect of the dominance of anticyclonic weather regimes and soil moisture-atmosphere interactions. The atmospheric circulation largely determines the amount of solar irradiation and the amount of precipitation in an area. These two variables are themselves major factors controlling the soil moisture. Thus, solar irradiation and precipitation are used as proxies to analyse extreme sunny and dry late winter/spring and summer seasons for the period 1958-2011 in Germany and adjacent areas. For this purpose, solar irradiation data from the European Center for Medium Range Weather Forecast 40-yr and interim re-analysis dataset, as well as remote sensing data are used. Precipitation data are taken from the Global Precipitation Climatology Project. To analyse the atmospheric circulation geopotential data at 850 hPa are also taken from the European Center for Medium Range Weather Forecast 40-yr and interim re-analysis datasets. For the years in which extreme summers in terms of high solar irradiation and low precipitation are identified, the previous late winter/spring conditions of solar irradiation and precipitation in Germany and adjacent areas are analysed. Results show that if the El Niño-Southern Oscillation (ENSO) is not very intensely developed, extremely high solar irradiation amounts, together with extremely low precipitation

  10. Increased frequency of ENSO extremes under greenhouse warming

    NASA Astrophysics Data System (ADS)

    Santoso, Agus; Cai, Wenju

    2015-04-01

    The El Nino Southern Oscillation (ENSO) is Earth's largest source of year-to-year climate variability which exerts significant environmental and socio-economic impacts worldwide. The rise of ENSO, signified by large changes in ocean and atmospheric circulations, occurs through a suite of Bjerknes coupled feedback processes in the equatorial Pacific Ocean. Observations over recent decades have seen some peculiar behaviour of ENSO that has challenged our scientific understanding of this remarkable phenomenon. 1982 and 1997 saw the strongest El Nino events in modern records, uniquely characterised by eastward propagating sea surface temperature anomalies, a behaviour not seen during moderate events and La Nina. The impacts were severe, causing multi billion dollars in damages, thousands of human lives lost, and destruction of marine habitats. The 1997 El Nino was followed by an exceptionally strong 1998 La Nina event which was also catastrophic. Given their significant impacts, one of the most pressing issues our society needs to address is whether and how ENSO will respond to the increase in atmospheric greenhouse gas concentrations. The increasing breadth of climate models available under the efforts of the Coupled Model Intercomparison Project (CMIP) has made addressing this issue possible. In contrast to previous finding of no robust ENSO response, recent research utilising the large CMIP database has found intermodel consensus of significant increases in the frequency of both El Nino and La Nina events that are 'extreme like', analogous to the 82, 97, and 98 events. The weakened westward flowing mean equatorial Pacific currents are expected to give rise to more frequent eastward propagating El Nino under greenhouse warming. The projected faster warming of the eastern equatorial Pacific Ocean than the surrounding regions would make it easier for atmospheric convection to shift eastward to generate rainfall response similar to that during an extreme El Nino. The

  11. Winter stratospheric warmings and their influence on the temperature regime in the lower ionosphere

    NASA Astrophysics Data System (ADS)

    Tarasenko, D. A.; Kidiiarova, V. G.; Milenkova, L. P.; Zakhariev, V. I.; Spasov, Kh. V.

    An analysis is presented of the relationship between the temperature conditions in the D layer of the ionosphere and the intensity of winter stratospheric warmings in different geographic regions, namely, high latitudes and midlatitudes in the Northern Hemisphere and high latitudes in the Southern Hemisphere. The relationships between the temperatures in the stratosphere and mesosphere and the parameters' transmission coefficient, defraction coefficient, and the phase of the two-year equatorial circulation cycle are considered. The temperature conditions in the stratosphere and mesosphere are found to be controlled by the quasi-two-year cycle of the equatorial circulation, which is connected with the intensity of winter stratospheric warmings.

  12. Extreme Winter/Early-Spring Temperature Anomalies in Central Europe

    NASA Technical Reports Server (NTRS)

    Otterman, Joseph; Atlas, Robert; Ardizzone, Joseph; Brakke, Thomas; Chou, Shu-Hsien; Jusem, Juan Carlos; Glantz, Michael; Rogers, Jeff; Sud, Yogesh; Susskind, Joel

    2000-01-01

    Extreme seasonal fluctuations of the surface-air temperature characterize the climate of central Europe, 45-60 deg North Temperature difference between warm 1990 and cold 1996 in the January-March period, persisting for more than two weeks at a time, amounted to 18 C for extensive areas. These anomalies in the surface-air temperature stem in the first place from differences in the low level flow from the eastern North-Atlantic: the value of the Index 1na of southwesterlies over the eastern North-Atlantic was 8.0 m/s in February 1990, but only 2.6 m/ s in February 1996. The primary forcing by warm advection to positive anomalies in monthly mean surface temperature produced strong synoptic-scale uplift at the 700 mb level over some regions in Europe. The strong uplift contributed in 1990 to a much larger cloud-cover over central Europe, which reduced heat-loss to space (greenhouse effect). Thus, spring arrived earlier than usual in 1990, but later than usual in 1996.

  13. Seasonal Climate Extremes : Mechanism, Predictability and Responses to Global Warming

    NASA Astrophysics Data System (ADS)

    Shongwe, M. E.

    2010-01-01

    Climate extremes are rarely occurring natural phenomena in the climate system. They often pose one of the greatest environmental threats to human and natural systems. Statistical methods are commonly used to investigate characteristics of climate extremes. The fitted statistical properties are often interpolated or extrapolated to give an indication of the likelihood of a certain event within a given period or interval. Under changing climatic conditions, the statistical properties of climate extremes are also changing. It is an important scientific goal to predict how the properties of extreme events change. To achieve this goal, observational and model studies aimed at revealing important features are a necessary prerequisite. Notable progress has been made in understanding mechanisms that influence climate variability and extremes in many parts of the globe including Europe. However, some of the recently observed unprecedented extremes cannot be fully explained from the already identified forcing factors. A better understanding of why these extreme events occur and their sensitivity to certain reinforcing and/or competing factors is useful. Understanding their basic form as well as their temporal variability is also vital and can contribute to global scientific efforts directed at advancing climate prediction capabilities, particularly making skilful forecasts and realistic projections of extremes. In this thesis temperature and precipitation extremes in Europe and Africa, respectively, are investigated. Emphasis is placed on the mechanisms underlying the occurrence of the extremes, their predictability and their likely response to global warming. The focus is on some selected seasons when extremes typically occur. An atmospheric energy budget analysis for the record-breaking European Autumn 2006 event has been carried out with the goal to identify the sources of energy for the extreme event. Net radiational heating is compared to surface turbulent fluxes of

  14. Increasing water cycle extremes in California and relation to ENSO cycle under global warming

    SciTech Connect

    Yoon, Jin -Ho; Wang, S. -Y. Simon; Gillies, Robert R.; Kravitz, Benjamin S.; Hipps, Lawrence; Rasch, Philip J.

    2015-10-21

    California has experienced its most severe drought in recorded history since the winter of 2013-2014. The long duration of drought has stressed statewide water resources and the economy, while fueling an extraordinary increase in wildfires. The effects of global warming on the regional climate include a hotter and drier climate, as well as earlier snowmelt, both of which exacerbate drought conditions. However, connections between a changing climate and how climate oscillations modulate regional water cycle extremes are not well understood. Here we analyze large-ensemble simulations of future climate change in California using the Community Earth System Model version 1 (CESM1) and multiple climate models participating in the Coupled Model Intercomparison Project Phase 5 (CMIP5). Both intense drought and excessive flooding are projected to increase by at least 50% toward the end of the 21st century. Furthermore, the projected increase in water cycle extremes is associated with tighter relation to El Niño and Southern Oscillation (ENSO), particularly extreme El Niño and La Niña events, which modulates California’s climate not only through its warm and cold phases, but also ENSO’s precursor patterns.

  15. Increasing water cycle extremes in California and relation to ENSO cycle under global warming

    DOE PAGES

    Yoon, Jin -Ho; Wang, S. -Y. Simon; Gillies, Robert R.; ...

    2015-10-21

    California has experienced its most severe drought in recorded history since the winter of 2013-2014. The long duration of drought has stressed statewide water resources and the economy, while fueling an extraordinary increase in wildfires. The effects of global warming on the regional climate include a hotter and drier climate, as well as earlier snowmelt, both of which exacerbate drought conditions. However, connections between a changing climate and how climate oscillations modulate regional water cycle extremes are not well understood. Here we analyze large-ensemble simulations of future climate change in California using the Community Earth System Model version 1 (CESM1)more » and multiple climate models participating in the Coupled Model Intercomparison Project Phase 5 (CMIP5). Both intense drought and excessive flooding are projected to increase by at least 50% toward the end of the 21st century. Furthermore, the projected increase in water cycle extremes is associated with tighter relation to El Niño and Southern Oscillation (ENSO), particularly extreme El Niño and La Niña events, which modulates California’s climate not only through its warm and cold phases, but also ENSO’s precursor patterns.« less

  16. [Effects of nighttime warming on winter wheat root growth and soil nutrient availability].

    PubMed

    Zhang, Ming-Qian; Chen, Jin; Guo, Jia; Tian, Yun-Lu; Yang, Shi-Jia; Zhang, Li; Yang, Bing; Zhang, Wei-Jian

    2013-02-01

    Climate warming has an obvious asymmetry between day and night, with a greater increment of air temperature at nighttime than at daytime. By adopting passive nighttime warming (PNW) system, a two-year field experiment of nighttime warming was conducted in the main production areas of winter wheat in China (Shijiazhuang of Hebei Province, Xuzhou of Jiangsu Province, Xuchang of Henan Province, and Zhenjiang of Jiangsu Province) in 2009 and 2010, with the responses of soil pH and available nutrient contents during the whole growth periods and of wheat root characteristics at heading stage determined. As compared with the control (no nighttime warming), nighttime warming decreased the soil pH and available nutrient contents significantly, and increased the root dry mass and root/shoot ratio to a certain extent. During the whole growth period of winter wheat, nighttime warming decreased the soil pH in Shijiazhuang, Xuzhou, Xuchang, and Zhenjiang averagely by 0.4%, 0.4%, 0.7%, and 0.9%, the soil alkaline nitrogen content averagely by 8.1%, 8.1%, 7.1%, and 6.0%, the soil available phosphorus content averagely by 15.7%, 12.1%, 19.6%, and 25.8%, and the soil available potassium content averagely by 11.5%, 7.6%, 7.6% , and 10.1%, respectively. However, nighttime warming increased the wheat root dry mass at heading stage in Shijiazhuang, Xuzhou, and Zhenjiang averagely by 31. 5% , 27.0%, and 14.5%, and the root/shoot ratio at heading stage in Shijiazhuang, Xuchang, and Zhenjiang averagely by 23.8%, 13.7% and 9.7%, respectively. Our results indicated that nighttime warming could affect the soil nutrient supply and winter wheat growth via affecting the soil chemical properties.

  17. Is Global Warming significantly affecting atmospheric circulation extremes?

    NASA Astrophysics Data System (ADS)

    Sardeshmukh, P. D.; Compo, G. P.; Penland, M. C.

    2012-12-01

    Although the anthropogenic influence on 20th century global warming is well established, the influence on the atmospheric circulation, especially on regional scales at which natural variability is relatively large, has proved harder to ascertain. And yet assertions are often made to this effect, especially in the media whenever an extreme warm or cold or dry or wet spell occurs and is tied to an apparent trend in the large-scale atmospheric circulation pattern. We are addressing this important issue using the longest currently available global atmospheric circulation dataset, an ensemble of 56 equally likely estimates of the atmospheric state within observational error bounds generated for every 6 hours from 1871 to the present in the 20th Century Reanalysis Project (20CR; Compo et al, QJRMS 2011). We previously presented evidence that long-term trends in the indices of several major modes of atmospheric circulation variability, including the North Atlantic Oscillation (NAO) and the tropical Pacific Walker Circulation (PWC), were weak or non-existent over the full period of record in the 20CR dataset. We have since investigated the possibility of a change in the probability density functions (PDFs) of the daily values of these indices, including changes in their tails, from the first to the second halves of the 20th century and found no statistically significant change. This was done taking into account the generally skewed and heavy-tailed character of these PDFs, and using both raw histograms and fitted "SGS" probability distributions (whose relevance in describing large-scale atmospheric variability was demonstrated in Sardeshmukh and Sura, J. Climate 2009) to assess the significance of any changes through extensive Monte Carlo simulations. We stress that without such an explicit accounting of departures from normal distributions, detection and attribution studies of changes in climate extremes may be seriously compromised and lead to wrong conclusions. Our

  18. Climatic Warming Increases Winter Wheat Yield but Reduces Grain Nitrogen Concentration in East China

    PubMed Central

    Deng, Aixing; Song, Zhenwei; Zhang, Baoming; Zhang, Weijian

    2014-01-01

    Climatic warming is often predicted to reduce wheat yield and grain quality in China. However, direct evidence is still lacking. We conducted a three-year experiment with a Free Air Temperature Increase (FATI) facility to examine the responses of winter wheat growth and plant N accumulation to a moderate temperature increase of 1.5°C predicted to prevail by 2050 in East China. Three warming treatments (AW: all-day warming; DW: daytime warming; NW: nighttime warming) were applied for an entire growth period. Consistent warming effects on wheat plant were recorded across the experimental years. An increase of ca. 1.5°C in daily, daytime and nighttime mean temperatures shortened the length of pre-anthesis period averagely by 12.7, 8.3 and 10.7 d (P<0.05), respectively, but had no significant impact on the length of the post-anthesis period. Warming did not significantly alter the aboveground biomass production, but the grain yield was 16.3, 18.1 and 19.6% (P<0.05) higher in the AW, DW and NW plots than the non-warmed plot, respectively. Warming also significantly increased plant N uptake and total biomass N accumulation. However, warming significantly reduced grain N concentrations while increased N concentrations in the leaves and stems. Together, our results demonstrate differential impacts of warming on the depositions of grain starch and protein, highlighting the needs to further understand the mechanisms that underlie warming impacts on plant C and N metabolism in wheat. PMID:24736557

  19. Climatic warming increases winter wheat yield but reduces grain nitrogen concentration in east China.

    PubMed

    Tian, Yunlu; Zheng, Chengyan; Chen, Jin; Chen, Changqing; Deng, Aixing; Song, Zhenwei; Zhang, Baoming; Zhang, Weijian

    2014-01-01

    Climatic warming is often predicted to reduce wheat yield and grain quality in China. However, direct evidence is still lacking. We conducted a three-year experiment with a Free Air Temperature Increase (FATI) facility to examine the responses of winter wheat growth and plant N accumulation to a moderate temperature increase of 1.5°C predicted to prevail by 2050 in East China. Three warming treatments (AW: all-day warming; DW: daytime warming; NW: nighttime warming) were applied for an entire growth period. Consistent warming effects on wheat plant were recorded across the experimental years. An increase of ca. 1.5°C in daily, daytime and nighttime mean temperatures shortened the length of pre-anthesis period averagely by 12.7, 8.3 and 10.7 d (P<0.05), respectively, but had no significant impact on the length of the post-anthesis period. Warming did not significantly alter the aboveground biomass production, but the grain yield was 16.3, 18.1 and 19.6% (P<0.05) higher in the AW, DW and NW plots than the non-warmed plot, respectively. Warming also significantly increased plant N uptake and total biomass N accumulation. However, warming significantly reduced grain N concentrations while increased N concentrations in the leaves and stems. Together, our results demonstrate differential impacts of warming on the depositions of grain starch and protein, highlighting the needs to further understand the mechanisms that underlie warming impacts on plant C and N metabolism in wheat.

  20. The role of the tropical West Pacific in the extreme Northern Hemisphere winter of 2013/2014

    NASA Astrophysics Data System (ADS)

    Watson, Peter A. G.; Weisheimer, Antje; Knight, Jeff R.; Palmer, T. N.

    2016-02-01

    In the 2013/2014 winter, the eastern U.S. 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 sea surface temperatures (SSTs) in the tropical West Pacific (TWPAC) were partly to blame due to them producing a Rossby wave train that propagated into the extratropics. We find that seasonal forecasts with the tropical atmosphere relaxed toward a reanalysis give 2013/2014 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 wave train over the North Pacific 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 Pacific and North America resembling those observed and that the tropical 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.

  1. The role of the tropical West Pacific in the extreme northern hemisphere winter of 2013/14

    NASA Astrophysics Data System (ADS)

    Watson, Peter; Weisheimer, Antje; Knight, Jeff; Palmer, Tim

    2016-04-01

    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 tropical West Pacific (TWPAC) were partly to blame due to their producing a Rossby wavetrain that propagated into the extratropics. We find that seasonal forecasts with the tropical 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 Pacific 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 Pacific and North America resembling those observed, but that the tropical 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.

  2. Extreme temperature contrast of the year 2012 in Greece: An exceptionally cold winter and a record breaking summer

    NASA Astrophysics Data System (ADS)

    Tolika, Konstantia; Anagnostopoulou, Christina; Maheras, Panagiotis; Velikou, Kondylia

    2013-04-01

    During the past decade several regions all over Europe have experienced severe heat waves with serious social and environmental impacts. The year of 2003 was characterized by record breaking high temperatures for central Europe, while the year of 2007 was a remarkably warm year of the majority of the Eastern Mediterranean. During this year, three major heat waves were detected in Greece during summer and abnormally high temperatures were also observed through the cold season of 2007. It was found that the winter minimum temperatures were statistically more extreme than the summer maxima. Moreover, exceptionally high maximum and minimum temperatures occurred in November of 2010 affection the entire Greek region while September of the following year was also characterized by large departures of maximum temperatures from the long term mean values and the highest minimum temperature average in comparison to the reference period 1958-2000. The past year (2012) could also be characterized as a year of extremes. This time a temperature contrast was detected in the domain of study with a prolonged cold - season spell during winter and new record - breaking extreme maximum and minimum summer temperatures. More specifically it was found that the summer of 2012 was the warmest one since 1958. The whole season was characterized by long - lasting warm conditions with large departures from the long term (up to 4oC for Tmax) and this warming phenomenon was more intense during July and August. In contrast the winter season (December 2011 - February 2012) was found to be in the ten coldest winters of the last 55 years. The departures from the mean are lower than summer (1oC to 1.5oC negative anomalies) but most of the days were found to have lower Tmax, Tmin and Tmean values than the average daily temperatures of the period 1958-2000. Finally, it is worth mentioning that the year of 2012 was characterized by the highest annual temperature range reaching up to 26oC in several

  3. Extreme winter cyclones and the extinction of a reindeer population (Invited)

    NASA Astrophysics Data System (ADS)

    Walsh, J. E.; Klein, D. R.; Shulski, M.

    2009-12-01

    While strong cyclones are not unusual are not unusual in the subpolar North Pacific storm track, an exceptional series of storm events in early 1964 decimated the reindeer population of St. Matthew Island in the central Bering Sea. This case illustrates how severe winter storms can lead to species extinction when overpopulated species are restricted to islands or fractured habitats where dispersal is not an option. The strongest storm occurred in early February when a surface low pressure system that originated over the warm waters offshore of Japan tracked eastward from the warm waters offshore of Japan. The intensification of the low then accelerated as the storm approached the Aleutians, where the central pressure decreased to 957 hPa, a pressure typical of Category 3 hurricanes. The track and intensity of the low were such that St. Matthew Island was in the storm’s northwest quadrant during the peak-intensity phase. The pressure difference between the intense cyclone and the Siberian high exceeded 100 hPa -- a pressure difference between these two locations that was the largest in the entire 60-year period of the NCEP reanalysis. This record pressure difference led to extremely strong northerly winds that brought bitterly cold arctic air over St. Matthew Island, which was in the storm’s northwest quadrant. The wind chill temperature dropped to -50°C and remained colder than -40°C almost continuously for a full week. In this presentation, we examine the storm’s evolution and place the winter of early 1964 into the context of the historical cyclone climatological of the North Pacific.

  4. Windowpane flounder (Scophthalmus aquosus) and winter flounder (Pseudopleuronectes americanus) responses to cold temperature extremes in a Northwest Atlantic estuary

    NASA Astrophysics Data System (ADS)

    Wilber, Dara H.; Clarke, Douglas G.; Alcoba, Catherine M.; Gallo, Jenine

    2016-01-01

    The effect of climate variability on flatfish includes not only the effects of warming on sensitive life history stages, but also impacts from more frequent or unseasonal extreme cold temperatures. Cold weather events can affect the overwintering capabilities of flatfish near their low temperature range limits. We examined the responses of two flatfish species, the thin-bodied windowpane (Scophthalmus aquosus) and cold-tolerant winter flounder (Pseudopleuronectes americanus), to variable winter temperatures in a Northwest Atlantic estuary using abundance and size data collected during a monitoring study, the Aquatic Biological Survey, conducted from 2002 to 2010. Winter and spring abundances of small (50 to 120 mm total length) juvenile windowpane were positively correlated with adult densities (spawning stock) and fall temperatures (thermal conditions experienced during post-settlement development for the fall-spawned cohort) of the previous year. Windowpane abundances in the estuary were significantly reduced and the smallest size class was nearly absent after several consecutive years with cold (minimum temperatures < 1 °C) winters. Interannual variation in winter flounder abundances was unrelated to the severity of winter temperatures. A Paulik diagram illustrates strong positive correlations between annual abundances of sequential winter flounder life history stages (egg, larval, Age-1 juvenile, and adult male) within the estuary, reflecting residency within the estuary through their first year of life. Temperature variables representing conditions during winter flounder larval and post-settlement development were not significant factors in multiple regression models exploring factors that affect juvenile abundances. Likewise, densities of predators known to consume winter flounder eggs and/or post-settlement juveniles were not significantly related to interannual variation in winter flounder juvenile abundances. Colder estuarine temperatures through the

  5. No snow for Christmas: the impact of the 2015 extreme winter on CO2 fluxes in European mountain grasslands

    NASA Astrophysics Data System (ADS)

    Cremonese, Edoardo; Galvagno, Marta; Hammerle, Albin; Filippa, Gianluca; Wohlfahrt, Georg

    2016-04-01

    The increasing frequency in extreme climate events is very likely to impact the Alps since this region is characterized by very sensitive ecosystems. Typical alpine ecosystems such as mountain grasslands, show a strong seasonality in carbon uptake and release mostly driven by the onset and the end of the snow season. Extreme climate events, such as long warm and/or dry periods, could change typical snow cover temporal pattern, thereby altering the duration of the period of CO2 uptake and release. In recent years many studies have analyzed the impact of delayed or anticipated snowmelt on alpine plant phenology, growth and carbon cycling. However, little is known on the effects of a delayed onset of the snow season. During 2015 the whole planet witnessed several record-breaking warm spells which exceptionally warmed the Alps where the temperature anomaly reached +4°C during both the autumn and winter periods. In particular, the onset of the 2015 winter in the Alps was marked by one of the most prolonged lack of snow in years. In this study, we investigate and discuss the impact of the altered temperature and precipitation pattern during the autumn/winter 2015 on the net ecosystem CO2 exchange of mountain grasslands at high and low altitudes measured by means of the eddy covariance method. In particular we test the following hypotheses: (i) The presence of a snowpack impedes plant photosynthesis, while without a snowpack, plant net CO2 uptake may be possible even during wintertime provided temperatures are warm enough. (ii) Below a snowpack, soil temperatures are around zero degrees Celsius, allowing for microbial activity resulting in intermediate soil respiration; without a snow cover soil temperatures may be either lower or higher than zero degrees Celsius, decreasing or increasing soil respiration. The magnitude and direction of the net ecosystem CO2 exchange of mountain grassland ecosystems is governed by the complex interplay of the factors addressed in

  6. Large Scale Drivers for the Extreme Storm Season over the North Atlantic and the UK in Winter 2013-14

    NASA Astrophysics Data System (ADS)

    Wild, Simon; Befort, Daniel J.; Leckebusch, Gregor C.

    2016-04-01

    The British Isles experienced exceptional stormy and rainy weather conditions in winter 2013-2014 while large parts of central North America recorded near record minimum surface temperatures values. Potential drivers for these cold conditions include increasingly warm surface waters of the tropical west Pacific. It has been suggested these increasing sea surface temperatures could also be the cause for extreme weather over the Europe, particularly the UK. Testing this hypothesis, we investigate mechanisms linking the tropical west Pacific and European wind storm activity. We will firstly analyse anomaly patterns along such a potential link in winter 2013-14. Secondly, we will investigate whether these identified anomaly patterns show a strong interannual relationship in the recent past. Our results, using primarily ERA-Interim Reanalysis from 1979 to 2014, show an absolute maximum of wind storm frequency over the northeast Atlantic and the British Isles in winter 2013-14. We also find absolute minimum surface temperatures in central North America and increased convective activity over the tropical west Pacific in the same season. The winter 2013-14 was additionally characterized by anomalous warm sea surface temperatures over the subtropical northwest Atlantic. Although the interannual variability of wind storms in the northeast Atlantic and surface temperatures in North America are significantly anti-correlated, we cannot directly relate wind storm frequency with tropical west Pacific anomalies. We thus conclude that the conditions over the Pacific in winter 2013-14 were favourable but not sufficient to explain the record number of wind storms in this season. Instead, we suggest that warm north Atlantic sea surface temperature anomalies in combination with cold surface temperatures over North America played a more important role for generating higher wind storm counts over the northeast Atlantic and the UK.

  7. Notes and Correspondence: The effect of enhanced greenhouse warming on winter cyclone frequencies and strengths

    SciTech Connect

    Lambert, S.J.

    1995-05-01

    The extratropical winter cyclone climatologies for the Northern and Southern Hemispheres are presented for a control, or 1 x CO{sub 2} simulation, and an enhanced greenhouse warming, or 2 x CO{sub 2} simulation, using the second generation Canadian Climate Centre general circulation model. When compared to the control climatology, the 2 x CO{sub 2} simulation exhibits a significant reduction in the total number of lows in both winter hemispheres. Although the total number of cyclones decreases, the frequency of intense cyclones increases, with this behavior being more significant in the Northern Hemisphere. Examination of the storm tracks in both simulations indicates that there is little change in their geographical positions with global warming. 10 refs., 8 figs., 4 tabs.

  8. Winter cold of eastern continental boundaries induced by warm ocean waters.

    PubMed

    Kaspi, Yohai; Schneider, Tapio

    2011-03-31

    In winter, northeastern North America and northeastern Asia are both colder than other regions at similar latitudes. This has been attributed to the effects of stationary weather systems set by elevated terrain (orography), and to a lack of maritime influences from the prevailing westerly winds. However, the differences in extent and orography between the two continents suggest that further mechanisms are involved. Here we show that this anomalous winter cold can result in part from westward radiation of large-scale atmospheric waves--nearly stationary Rossby waves--generated by heating of the atmosphere over warm ocean waters. We demonstrate this mechanism using simulations with an idealized general circulation model, with which we show that the extent of the cold region is controlled by properties of Rossby waves, such as their group velocity and its dependence on the planetary rotation rate. Our results show that warm ocean waters contribute to the contrast in mid-latitude winter temperatures between eastern and western continental boundaries not only by warming western boundaries, but also by cooling eastern boundaries.

  9. How much do precipitation extremes change in a warming climate?

    NASA Astrophysics Data System (ADS)

    Shiu, Chein-Jung; Liu, Shaw Chen; Fu, Congbin; Dai, Aiguo; Sun, Ying

    2012-09-01

    Daily data from reanalyses of the European Centre for Medium-Range Weather Forecasts (ECMWF) and the National Centers for Environmental Prediction (NCEP) are analyzed to study changes in precipitation intensity with respect to global mean temperature. The results are in good agreement with those derived from the Global Precipitation Climatology Project (GPCP) data by Liu et al. (2009), providing an independent verification for large changes in the precipitation extremes: about 100% increase for the annual top 10% heavy precipitation and about 20% decrease for the light and moderate precipitation for one degree warming in the global temperature. These changes can substantially increase the risk of floods as well as droughts, thus severely affecting the global ecosystems. Atmospheric models used in the reanalysis mode, with the benefit of observed wind and moisture fields, appear to be capable of realistically simulating the change of precipitation intensity with global temperature. In comparison, coupled climate models are capable of simulating the shape of the change in precipitation intensity, but underestimate the magnitude of the change by about one order of magnitude. The most likely reason of the underestimation is that the typical spatial resolution of climate models is too coarse to resolve atmospheric convection.

  10. The Trends in Excess Mortality in Winter vs. Summer in a Sub-Tropical City and Its Association with Extreme Climate Conditions

    PubMed Central

    Chau, Pui Hing; Woo, Jean

    2015-01-01

    While there is literature on excess winter mortality, there are few studies examining the evolution of its trend which may be changing in parallel with global warming. This study aimed to examine the trend in the excess mortality in winter as compared to summer among the older population in a sub-tropical city and to explore its association with extreme weather. We used a retrospective study based on the registered deaths among the older population in Hong Kong during 1976-2010. An Excess Mortality for Winter versus Summer (EMWS) Index was used to quantify the excess number of deaths in winter compared to summer. Multiple linear regressions were used to analyze the trends and its association with extreme weather. Overall, the EMWS Index for ischemic heart disease, cerebrovascular diseases, chronic lower respiratory diseases, pneumonia, and other causes were 43.0%, 34.2%, 42.7%, 23.4% and 17.6%, respectively. Significant decline was observed in the EMWS Index for chronic lower respiratory diseases and other causes. The trend in the index for cerebrovascular diseases depended on the age group, with older groups showing a decline but younger groups not showing any trend. Meteorological variables, in terms of extreme weather, were associated with the trends in the EMWS Index. We concluded that shrinking excess winter mortality from cerebrovascular diseases and chronic lower respiratory diseases was found in a sub-tropical city. These trends were associated with extreme weather, which coincided with global warming. PMID:25993635

  11. Stratospheric variability contributed to and sustained the recent hiatus in Eurasian winter warming

    NASA Astrophysics Data System (ADS)

    Garfinkel, Chaim I.; Son, Seok-Woo; Song, Kanghyun; Aquila, Valentina; Oman, Luke D.

    2017-01-01

    The recent hiatus in global-mean surface temperature warming was characterized by a Eurasian winter cooling trend, and the cause(s) for this cooling is unclear. Here we show that the observed hiatus in Eurasian warming was associated with a recent trend toward weakened stratospheric polar vortices. Specifically, by calculating the change in Eurasian surface air temperature associated with a given vortex weakening, we demonstrate that the recent trend toward weakened polar vortices reduced the anticipated Eurasian warming due to increasing greenhouse gas concentrations. Those model integrations whose stratospheric vortex evolution most closely matches that in reanalysis data also simulate a hiatus. While it is unclear whether the recent weakening of the midwinter stratospheric polar vortex was forced, a properly configured model can simulate substantial deviations of the polar vortex on decadal timescales and hence such hiatus events, implying that similar hiatus events may recur even as greenhouse gas concentrations rise.

  12. Low clouds suppress Arctic air formation and amplify high-latitude continental winter warming

    PubMed Central

    Cronin, Timothy W.; Tziperman, Eli

    2015-01-01

    High-latitude continents have warmed much more rapidly in recent decades than the rest of the globe, especially in winter, and the maintenance of warm, frost-free conditions in continental interiors in winter has been a long-standing problem of past equable climates. We use an idealized single-column atmospheric model across a range of conditions to study the polar night process of air mass transformation from high-latitude maritime air, with a prescribed initial temperature profile, to much colder high-latitude continental air. We find that a low-cloud feedback—consisting of a robust increase in the duration of optically thick liquid clouds with warming of the initial state—slows radiative cooling of the surface and amplifies continental warming. This low-cloud feedback increases the continental surface air temperature by roughly two degrees for each degree increase of the initial maritime surface air temperature, effectively suppressing Arctic air formation. The time it takes for the surface air temperature to drop below freezing increases nonlinearly to ∼10 d for initial maritime surface air temperatures of 20 °C. These results, supplemented by an analysis of Coupled Model Intercomparison Project phase 5 climate model runs that shows large increases in cloud water path and surface cloud longwave forcing in warmer climates, suggest that the “lapse rate feedback” in simulations of anthropogenic climate change may be related to the influence of low clouds on the stratification of the lower troposphere. The results also indicate that optically thick stratus cloud decks could help to maintain frost-free winter continental interiors in equable climates. PMID:26324919

  13. Low clouds suppress Arctic air formation and amplify high-latitude continental winter warming.

    PubMed

    Cronin, Timothy W; Tziperman, Eli

    2015-09-15

    High-latitude continents have warmed much more rapidly in recent decades than the rest of the globe, especially in winter, and the maintenance of warm, frost-free conditions in continental interiors in winter has been a long-standing problem of past equable climates. We use an idealized single-column atmospheric model across a range of conditions to study the polar night process of air mass transformation from high-latitude maritime air, with a prescribed initial temperature profile, to much colder high-latitude continental air. We find that a low-cloud feedback--consisting of a robust increase in the duration of optically thick liquid clouds with warming of the initial state--slows radiative cooling of the surface and amplifies continental warming. This low-cloud feedback increases the continental surface air temperature by roughly two degrees for each degree increase of the initial maritime surface air temperature, effectively suppressing Arctic air formation. The time it takes for the surface air temperature to drop below freezing increases nonlinearly to ∼ 10 d for initial maritime surface air temperatures of 20 °C. These results, supplemented by an analysis of Coupled Model Intercomparison Project phase 5 climate model runs that shows large increases in cloud water path and surface cloud longwave forcing in warmer climates, suggest that the "lapse rate feedback" in simulations of anthropogenic climate change may be related to the influence of low clouds on the stratification of the lower troposphere. The results also indicate that optically thick stratus cloud decks could help to maintain frost-free winter continental interiors in equable climates.

  14. Nutritional condition of Pacific Black Brant wintering at the extremes of their range

    USGS Publications Warehouse

    Mason, D.D.; Barboza, P.S.; Ward, D.H.

    2006-01-01

    Endogenous stores of energy allow birds to survive periods of severe weather and food shortage during winter. We documented changes in lipid, protein, moisture, and ash in body tissues of adult female Pacific Black Brant (Branta bernicla nigricans) and modeled the energetic costs of wintering. Birds were collected at the extremes of their winter range, in Alaska and Baja California, Mexico. Body lipids decreased over winter for birds in Alaska but increased for those in Baja California. Conversely, body protein increased over winter for Brant in Alaska and remained stable for birds in Baja California. Lipid stores likely fuel migration for Brant wintering in Baja California and ensure winter survival for those in Alaska. Increases in body protein may support earlier reproduction for Brant in Alaska. Predicted energy demands were similar between sites during late winter but avenues of expenditure were different. Birds in Baja California spent more energy on lipid synthesis while those in Alaska incurred higher thermoregulatory costs. Estimated daily intake rates of eelgrass were similar between sites in early winter; however, feeding time was more constrained in Alaska because of high tides and short photoperiods. Despite differences in energetic costs and foraging time, Brant wintering at both sites appeared to be in good condition. We suggest that wintering in Alaska may be more advantageous than long-distance migration if winter survival is similar between sites and constraints on foraging time do not impair body condition. ?? The Cooper Ornithological Society 2006.

  15. Influence of atmospheric energy transport on amplification of winter warming in the Arctic

    NASA Astrophysics Data System (ADS)

    Alekseev, Genrikh; Kuzmina, Svetlana; Urazgildeeva, Aleksandra; Bobylev, Leonid

    2016-04-01

    The study was performed on base reanalysis ERA/Interim to discover the link between amplified warming in the high Arctic and the atmospheric transport of heat and water vapor through the 70 ° N. The partitioning transports across the Atlantic and Pacific "gates" is established the link between variations of atmospheric flux through the "gates" and a larger part of the variability of the average surface air temperature, water vapor content and its trends in the winter 1980-2014. Influence of winter (December-February) atmospheric transport across the Atlantic "gate" at the 1000 hPa on variability of average for January-February surface air temperature to north 70° N is estimated correlation coefficient 0.75 and contribution to the temperature trend 40%. These results for the first time denote the leading role of increasing atmospheric transport on the amplification of winter warming in the high Arctic. The investigation is supported with RFBR project 15-05-03512.

  16. Winter warming and summer monsoon reduction after volcanic eruptions in Coupled Model Intercomparison Project 5 (CMIP5) simulations

    NASA Astrophysics Data System (ADS)

    Zambri, Brian; Robock, Alan

    2016-10-01

    Though previous studies have shown that state-of-the-art climate models are rather imperfect in their simulations of the climate response to large volcanic eruptions, the results depend on how the analyses were done. Observations show that all recent large tropical eruptions were followed by winter warming in the first Northern Hemisphere (NH) winter after the eruption, with little such response in the second winter, yet a number of the evaluations have combined the first and second winters. We have looked at just the first winter after large eruptions since 1850 in the Coupled Model Intercomparison Project 5 historical simulations and find that most models do produce a winter warming signal, with warmer temperatures over NH continents and a stronger polar vortex in the lower stratosphere. We also examined NH summer precipitation responses in the first year after these large volcanic eruptions and find clear reductions of summer monsoon rainfall.

  17. Arctic sea ice, Eurasia snow, and extreme winter haze in China

    PubMed Central

    Zou, Yufei; Wang, Yuhang; Zhang, Yuzhong; Koo, Ja-Ho

    2017-01-01

    The East China Plains (ECP) region experienced the worst haze pollution on record for January in 2013. We show that the unprecedented haze event is due to the extremely poor ventilation conditions, which had not been seen in the preceding three decades. Statistical analysis suggests that the extremely poor ventilation conditions are linked to Arctic sea ice loss in the preceding autumn and extensive boreal snowfall in the earlier winter. We identify the regional circulation mode that leads to extremely poor ventilation over the ECP region. Climate model simulations indicate that boreal cryospheric forcing enhances the regional circulation mode of poor ventilation in the ECP region and provides conducive conditions for extreme haze such as that of 2013. Consequently, extreme haze events in winter will likely occur at a higher frequency in China as a result of the changing boreal cryosphere, posing difficult challenges for winter haze mitigation but providing a strong incentive for greenhouse gas emission reduction. PMID:28345056

  18. Arctic sea ice, Eurasia snow, and extreme winter haze in China.

    PubMed

    Zou, Yufei; Wang, Yuhang; Zhang, Yuzhong; Koo, Ja-Ho

    2017-03-01

    The East China Plains (ECP) region experienced the worst haze pollution on record for January in 2013. We show that the unprecedented haze event is due to the extremely poor ventilation conditions, which had not been seen in the preceding three decades. Statistical analysis suggests that the extremely poor ventilation conditions are linked to Arctic sea ice loss in the preceding autumn and extensive boreal snowfall in the earlier winter. We identify the regional circulation mode that leads to extremely poor ventilation over the ECP region. Climate model simulations indicate that boreal cryospheric forcing enhances the regional circulation mode of poor ventilation in the ECP region and provides conducive conditions for extreme haze such as that of 2013. Consequently, extreme haze events in winter will likely occur at a higher frequency in China as a result of the changing boreal cryosphere, posing difficult challenges for winter haze mitigation but providing a strong incentive for greenhouse gas emission reduction.

  19. Observed decreases in the Canadian outdoor skating season due to recent winter warming

    NASA Astrophysics Data System (ADS)

    Damyanov, Nikolay N.; Damon Matthews, H.; Mysak, Lawrence A.

    2012-03-01

    Global warming has the potential to negatively affect one of Canada’s primary sources of winter recreation: hockey and ice skating on outdoor rinks. Observed changes in winter temperatures in Canada suggest changes in the meteorological conditions required to support the creation and maintenance of outdoor skating rinks; while there have been observed increases in the ice-free period of several natural water bodies, there has been no study of potential trends in the duration of the season supporting the construction of outdoor skating rinks. Here we show that the outdoor skating season (OSS) in Canada has significantly shortened in many regions of the country as a result of changing climate conditions. We first established a meteorological criterion for the beginning, and a proxy for the length of the OSS. We extracted this information from daily maximum temperature observations from 1951 to 2005, and tested it for significant changes over time due to global warming as well as due to changes in patterns of large-scale natural climate variability. We found that many locations have seen a statistically significant decrease in the OSS length, particularly in Southwest and Central Canada. This suggests that future global warming has the potential to significantly compromise the viability of outdoor skating in Canada.

  20. North Atlantic Surface Winds Examined as the Source of Warm Advection into Europe in Winter

    NASA Technical Reports Server (NTRS)

    Otterman, J.; Angell, J. K.; Ardizzone, J.; Atlas, Robert; Schubert, S.; Starr, D.; Wu, M.-L.

    2002-01-01

    When from the southwest, North Atlantic ocean surface winds are known to bring warm and moist airmasses into central Europe in winter. By tracing backward trajectories from western Europe, we establish that these airmasses originate in the southwestern North Atlantic, in the very warm regions of the Gulf Stream. Over the eastern North Atlantic, Lt the gateway to Europe, the ocean-surface winds changed directions in the second half of the XXth century, those from the northwest and from the southeast becoming so infrequent, that the direction from the southwest became even more dominant. For the January-to-March period, the strength of south-westerlies in this region, as well as in the source region, shows in the years 1948-1995 a significant increase, above 0.2 m/sec/ decade. Based on the sensitivity of the surface temperature in Europe, slightly more than 1 C for a 1m/sec increase in the southwesterly wind, found in the previous studies, the trend in the warm advection accounts for a large part of the warming in Europe established for this period in several reports. However, for the most recent years, 1996-2001, the positive trend in the southwesterly advection appears to be is broken, which is consistent with unseasonally cold events reported in Europe in those winters. This study had, some bearing on evaluating the respective roles of the North Atlantic Oscillation and the Greenhouse Gas Global warming, GGG, in the strong winter warming observed for about half a century over the northern-latitude continents. Changes in the ocean-surface temperatures induced by GGG may have produced the dominant southwesterly direction of the North Atlantic winds. However, this implies a monotonically (apart from inherent interannual variability) increasing advection, and if the break in the trend which we observe after 1995 persists, this mechanism is counter-indicated. The 1948-1995 trend in the south-westerlies could then be considered to a large degree attributable to the

  1. Potentially Extreme Population Displacement and Concentration in the Tropics Under Non-Extreme Warming

    PubMed Central

    Hsiang, Solomon M.; Sobel, Adam H.

    2016-01-01

    Evidence increasingly suggests that as climate warms, some plant, animal, and human populations may move to preserve their environmental temperature. The distances they must travel to do this depends on how much cooler nearby surfaces temperatures are. Because large-scale atmospheric dynamics constrain surface temperatures to be nearly uniform near the equator, these displacements can grow to extreme distances in the tropics, even under relatively mild warming scenarios. Here we show that in order to preserve their annual mean temperatures, tropical populations would have to travel distances greater than 1000 km over less than a century if global mean temperature rises by 2 °C over the same period. The disproportionately rapid evacuation of the tropics under such a scenario would cause migrants to concentrate in tropical margins and the subtropics, where population densities would increase 300% or more. These results may have critical consequences for ecosystem and human wellbeing in tropical contexts where alternatives to geographic displacement are limited. PMID:27278823

  2. Potentially Extreme Population Displacement and Concentration in the Tropics Under Non-Extreme Warming.

    PubMed

    Hsiang, Solomon M; Sobel, Adam H

    2016-06-09

    Evidence increasingly suggests that as climate warms, some plant, animal, and human populations may move to preserve their environmental temperature. The distances they must travel to do this depends on how much cooler nearby surfaces temperatures are. Because large-scale atmospheric dynamics constrain surface temperatures to be nearly uniform near the equator, these displacements can grow to extreme distances in the tropics, even under relatively mild warming scenarios. Here we show that in order to preserve their annual mean temperatures, tropical populations would have to travel distances greater than 1000 km over less than a century if global mean temperature rises by 2 °C over the same period. The disproportionately rapid evacuation of the tropics under such a scenario would cause migrants to concentrate in tropical margins and the subtropics, where population densities would increase 300% or more. These results may have critical consequences for ecosystem and human wellbeing in tropical contexts where alternatives to geographic displacement are limited.

  3. Potentially Extreme Population Displacement and Concentration in the Tropics Under Non-Extreme Warming

    NASA Astrophysics Data System (ADS)

    Hsiang, Solomon M.; Sobel, Adam H.

    2016-06-01

    Evidence increasingly suggests that as climate warms, some plant, animal, and human populations may move to preserve their environmental temperature. The distances they must travel to do this depends on how much cooler nearby surfaces temperatures are. Because large-scale atmospheric dynamics constrain surface temperatures to be nearly uniform near the equator, these displacements can grow to extreme distances in the tropics, even under relatively mild warming scenarios. Here we show that in order to preserve their annual mean temperatures, tropical populations would have to travel distances greater than 1000 km over less than a century if global mean temperature rises by 2 °C over the same period. The disproportionately rapid evacuation of the tropics under such a scenario would cause migrants to concentrate in tropical margins and the subtropics, where population densities would increase 300% or more. These results may have critical consequences for ecosystem and human wellbeing in tropical contexts where alternatives to geographic displacement are limited.

  4. Intensity of heat stress in winter wheat—phenology compensates for the adverse effect of global warming

    NASA Astrophysics Data System (ADS)

    Eyshi Rezaei, Ehsan; Siebert, Stefan; Ewert, Frank

    2015-02-01

    Higher temperatures during the growing season are likely to reduce crop yields with implications for crop production and food security. The negative impact of heat stress has also been predicted to increase even further for cereals such as wheat under climate change. Previous empirical modeling studies have focused on the magnitude and frequency of extreme events during the growth period but did not consider the effect of higher temperature on crop phenology. Based on an extensive set of climate and phenology observations for Germany and period 1951-2009, interpolated to 1 × 1 km resolution and provided as supplementary data to this article (available at stacks.iop.org/ERL/10/024012/mmedia), we demonstrate a strong relationship between the mean temperature in spring and the day of heading (DOH) of winter wheat. We show that the cooling effect due to the 14 days earlier DOH almost fully compensates for the adverse effect of global warming on frequency and magnitude of crop heat stress. Earlier heading caused by the warmer spring period can prevent exposure to extreme heat events around anthesis, which is the most sensitive growth stage to heat stress. Consequently, the intensity of heat stress around anthesis in winter crops cultivated in Germany may not increase under climate change even if the number and duration of extreme heat waves increase. However, this does not mean that global warning would not harm crop production because of other impacts, e.g. shortening of the grain filling period. Based on the trends for the last 34 years in Germany, heat stress (stress thermal time) around anthesis would be 59% higher in year 2009 if the effect of high temperatures on accelerating wheat phenology were ignored. We conclude that climate impact assessments need to consider both the effect of high temperature on grain set at anthesis but also on crop phenology.

  5. Short-term cropland responses to temperature extreme events during late winter

    NASA Astrophysics Data System (ADS)

    De Simon, G.; Alberti, G.; Delle Vedove, G.; Peressotti, A.; Zaldei, A.; Miglietta, F.

    2013-08-01

    In recent years, several studies have focused on terrestrial ecosystem response to extreme events. Most of this research has been conducted in natural ecosystems, but few have considered agroecosystems. In this study, we investigated the impact of a manipulated warmer or cooler late winter/early spring on the carbon budget and final harvest of a soybean crop (Glycine max (L.) Merr.). Soil temperature was altered by manipulating soil albedo by covering the soil surface with a layer of inert silica gravel. We tested three treatments - cooling (Co), warming (W), mix (M) - and control (C). An automated system continuously measured soil heterotrophic respiration (Rh), soil temperature profiles, and soil water content across the entire year in each plot. Phenological phases were periodically assessed and final harvest was measured in each plot. Results showed that treatments had only a transient effect on daily Rh rates, which did not result in a total annual carbon budget significantly different from control, even though cooling showed a significant reduction in final harvest. We also observed anticipation in emergence in both W and M treatments and a delay in emergence for Co. Moreover, plant density and growth increased in W and M and decreased in Co. In conclusion, from the results of our experiment we can assert that an increase in the frequency of both heat and cold waves is unlikely to have large effects on the overall annual carbon balance of irrigated croplands.

  6. Short-term cropland responses to temperature extreme events during late winter

    NASA Astrophysics Data System (ADS)

    De Simon, G.; Alberti, G.; Delle Vedove, G.; Peressotti, A.; Zaldei, A.; Miglietta, F.

    2013-04-01

    In recent years, several studies have focused on terrestrial ecosystem response to extreme events. Most of this research has been conducted in natural ecosystems, but few have considered agro-ecosystems. In this study, we investigated the impact of a manipulated warmer or cooler late winter-early spring on the carbon budget and final harvest of a soybean crop (Glycine max (L.) Merr.). Soil temperature was altered by manipulating soil albedo by covering the soil surface with a layer of inert silica gravel. We tested three treatments: cooling (Co), warming (W), mix (M) and control (C). An automated system continuously measured soil heterotrophic respiration (Rh), soil temperature profiles, and soil water content across the entire year in each plot. Phenological phases were periodically assessed and final harvest was measured in each plot. Results showed that treatments had only a transient effect on daily Rh rates which did not result in a total annual carbon budget significantly different from control, even though cooling showed a significant reduction in final harvest. We also observed anticipation in seed germination in both W and M treatments and a delay in germination for Co. Moreover, plant density and growth increased in W and M and decreased in Co.

  7. The 2015-2016 Arctic winter: Perspectives on extremes in polar processing and meteorological variability from the 12-year record of Aura Microwave Limb Sounder measurements

    NASA Astrophysics Data System (ADS)

    Santee, Michelle; Manney, Gloria; Lambert, Alyn; Livesey, Nathaniel; Lawrence, Zachary

    2016-04-01

    In the last decade, the Arctic lower stratosphere has seen some of the most dynamically disturbed winters, with stratospheric sudden warmings that curtailed polar processing early in the season and limited chemical ozone loss, as well as several winters marked by exceptionally cold conditions and severe chemical ozone loss. The occurrence in recent winters of different combinations of extreme meteorological conditions, and their impact on polar chemical processes, has underscored the Arctic stratosphere's sensitivity to a spectrum of dynamical variability. Launched as part of NASA's Aura satellite in July 2004, the Microwave Limb Sounder (MLS) provides an extensive suite of measurements enabling quantification of polar processing and chemical ozone loss. Here we use MLS observations in conjunction with meteorological analyses in a comprehensive analysis of the Arctic winter of 2015-2016. An unusually large volume of low temperatures in the early winter led to strong depletion in gas-phase HNO3 and H2O associated with polar stratospheric cloud formation. As a consequence of this early-winter processing and an elongated vortex with significant portions exposed to sunlight, substantial chlorine activation (enhanced abundances of ClO, depressed abundances of HCl) was evident far earlier than is typical in Arctic winter. The degree of polar processing and chemical ozone loss in this winter will be placed in the context of the previous 11 Arctic winters observed by Aura MLS.

  8. Winter warming delays dormancy release, advances budburst, alters carbohydrate metabolism and reduces yield in a temperate shrub.

    PubMed

    Pagter, Majken; Andersen, Uffe Brandt; Andersen, Lillie

    2015-03-23

    Global climate models predict an increase in the mean surface air temperature, with a disproportionate increase during winter. Since temperature is a major driver of phenological events in temperate woody perennials, warming is likely to induce changes in a range of these events. We investigated the impact of slightly elevated temperatures (+0.76 °C in the air, +1.35 °C in the soil) during the non-growing season (October-April) on freezing tolerance, carbohydrate metabolism, dormancy release, spring phenology and reproductive output in two blackcurrant (Ribes nigrum) cultivars to understand how winter warming modifies phenological traits in a woody perennial known to have a large chilling requirement and to be sensitive to spring frost. Warming delayed dormancy release more in the cultivar 'Narve Viking' than in the cultivar 'Titania', but advanced budburst and flowering predominantly in 'Titania'. Since 'Narve Viking' has a higher chilling requirement than 'Titania', this indicates that, in high-chilling-requiring genotypes, dormancy responses may temper the effect of warming on spring phenology. Winter warming significantly reduced fruit yield the following summer in both cultivars, corroborating the hypothesis that a decline in winter chill may decrease reproductive effort in blackcurrant. Elevated winter temperatures tended to decrease stem freezing tolerance during cold acclimation and deacclimation, but it did not increase the risk of freeze-induced damage mid-winter. Plants at elevated temperature showed decreased levels of sucrose in stems of both cultivars and flower buds of 'Narve Viking', which, in buds, was associated with increased concentrations of glucose and fructose. Hence, winter warming influences carbohydrate metabolism, but it remains to be elucidated whether decreased sucrose levels account for any changes in freezing tolerance. Our results demonstrate that even a slight increase in winter temperature may alter phenological traits in

  9. Has global warming changed timing of winter-spring streamflows over North America?

    NASA Astrophysics Data System (ADS)

    Kam, J.; Knutson, T. R.; Milly, P. C. D.

    2015-12-01

    Wherever snowmelt runoff substantially contributes to winter-spring streamflows, warmer winter-spring temperature can accelerate snow melt and reduce later streamflows. These changes can adversely affect human activities and ecological communities (e.g. flood, drought, salmon survival rate, and blooming season). Here we investigate changes in timing of winter-spring streamflows over North America (NA) during 1933-2013 and 1951-2000 using observed streamflow and simulated runoff from pre-industrial (unforced) control and historical (realistically forced) runs from the Geophysical Fluid Dynamics Laboratory Climate Model version 3. The study regions are north of 41˚N in NA. We analyze winter-spring center of volume date (WSCV), the date by which half of the accumulated January through June daily streamflow volume occurs. We first performed a sliding trend analysis of WSCV for time periods starting in various years (1951 through 1984) and ending in 2000. We found that the observed decreasing trends (Theil-Sen slopes) of WSCV over the northeast and northwest U.S. regions are at the edge of detectability (i.e., lie near the edge of the 5th-95th percentile envelope of control runs) for trends beginning any time between 1950 and 1970, but are consistent with the envelope of historical runs for all beginning trend years. Interestingly, for the 1933-2013 analysis, results for the northwest U.S. show that the observed trends of WSCV are positive for periods beginning as early as the mid-1960s, and inconsistent with historical runs for periods beginning in the mid-1950s and later. Aside from this inconsistency, observed trends to 2013 are consistent with both control and historical runs. This study suggests that internal variability has played a major role in timing of winter-spring streamflows to date, despite global warming, and thus that clear detection and attribution of WSCV trends in the study regions may require longer streamflow records than those now available.

  10. Observed Variability and Trends In Winter Extreme Minimum in Turkey, From 1966-2014

    NASA Astrophysics Data System (ADS)

    Acar Deniz, Zahide; Gonencgil, Barbaros

    2016-04-01

    Knowledge of extreme temperature events is consequential physical effects. Cold and hot events have delimitated activity of human and quality of life. In this study, winter temperature extremes and their spatiotemporal variability are investigated at 156 meteorological stations in Turkey. We have chosen the following two indices of extremes; frequency of days with minimum temperature below the 1966-2014 mean 1st (extreme cold nights) and 5th (cold nights) percentiles. Trends in extreme minimum temperature have been analyzed from 1966 to 2014 in winter season. In order to detect possible trends in extreme temperature over the Turkey, the Mann-Kendall test has applied to the annual percentile series. The lowest minimum temperature extreme values are observed in the east of Turkey. The most extreme cold events have been experienced in 1972. The Central and eastern regions of Turkey, be effective in the continental climate, there are increasing numbers of extreme cold night events. Extreme cold events are less observed in coastal stations. The number of extreme cold events has been observed a downward trend since 1990. The decreasing trends are not statistically significant. This situation displays cold events have fewer experienced from year to year. This study is supported by the Turkish Scientific and Technical Research Institute (Project number: 114Y417). Keywords: Extreme temperature, cold events, Mann-Kendall, Turkey.

  11. Energy consumption and the unexplained winter warming over northern Asia and North America

    NASA Astrophysics Data System (ADS)

    Zhang, Guang J.; Cai, Ming; Hu, Aixue

    2013-05-01

    The worldwide energy consumption in 2006 was close to 498 exajoules. This is equivalent to an energy convergence of 15.8TW into the populated regions, where energy is consumed and dissipated into the atmosphere as heat. Although energy consumption is sparsely distributed over the vast Earth surface and is only about 0.3% of the total energy transport to the extratropics by atmospheric and oceanic circulations, this anthropogenic heating could disrupt the normal atmospheric circulation pattern and produce a far-reaching effect on surface air temperature. We identify the plausible climate impacts of energy consumption using a global climate model. The results show that the inclusion of energy use at 86 model grid points where it exceeds 0.4Wm-2 can lead to remote surface temperature changes by as much as 1K in mid- and high latitudes in winter and autumn over North America and Eurasia. These regions correspond well to areas with large differences in surface temperature trends between observations and global warming simulations forced by all natural and anthropogenic forcings. We conclude that energy consumption is probably a missing forcing for the additional winter warming trends in observations.

  12. Cropland responses to extreme winter temperature events: results from a manipulation experiment in north-eastern Italy

    NASA Astrophysics Data System (ADS)

    De Simon, G.; Alberti, G.; Delle Vedove, G.; Peressotti, A.; Zaldei, A.; Miglietta, F.

    2011-12-01

    In the last years, several studies has focused on terrestrial ecosystem response to climate warming. Most of them have been conducted on natural ecosystems (forests or grasslands), but few have considered intensively managed ecosystems such as croplands despite of their global extension. In particular, extreme events, such as temperature changes outside the growing season (winter) when soil is not covered by plants, can have a strong impact on soil respiration, residues decomposition, yield and overall net biome production (NBP). In this study, we investigated the response of soil respiration (total and heterotrophic), aboveground NPP, yield and NBP on a soybean crop (Glycine max (L.) Merr.) due to a manipulated warmer or cooler winter. The experiment was carried out in Beano (46°00' N 13°01'E, Italy). Soil albedo and soil temperature were manipulated by covering soil surface during late winter with a layer of inert ceramized silica gravel. We tested three treatments with three replicates each: cooling (Co; white gravel), warming (W; black gravel), mix (M; black and white 4:1 gravel) and control (C; bare soil). An automated soil respiration system measured continuously total soil CO2 efflux across all the year and heterotrophic respiration after sowing in root exclusion subplots. Additionally, soil temperature profiles (0, 2.5, 5 and 10 cm depth), soil water content (between 5 and 10 cm depth) were monitored in each plot. After sowing, soybean phenological phases were periodically assessed and final yield was measured in each plot. Preliminary results showed a significant change in upper soil temperature between gravel application and canopy closure (maximum of + 5.8 °C and - 6.8 °C in the warming and cooling treatments, respectively). However, warming had only a transient effect on soil respiration (increase) before sowing. Thereafter, as soon as fresh organic matter availability decreased, soil respiration rate decreased and annual budget was not

  13. Cropland responses to extreme winter temperature events: results from a manipulation experiment in north-eastern Italy

    NASA Astrophysics Data System (ADS)

    De Simon, G.; Alberti, G.; Delle Vedove, G.; Peressotti, A.; Zaldei, A.; Miglietta, F.

    2012-04-01

    In the last years, several studies has focused on terrestrial ecosystem response to climate warming. Most of them have been conducted on natural ecosystems (forests or grasslands), but few have considered intensively managed ecosystems such as croplands despite of their global extension. In particular, extreme events, such as temperature changes outside the growing season (winter) when soil is not covered by plants, can have a strong impact on soil respiration, residues decomposition, yield and overall net biome production (NBP). In this study, we investigated the response of soil respiration (total and heterotrophic), aboveground NPP, yield and NBP on a soybean crop (Glycine max (L.) Merr.) due to a manipulated warmer or cooler winter. The experiment was carried out in Beano (46°00' N 13°01'E, Italy). Soil albedo and soil temperature were manipulated by covering soil surface during late winter with a layer of inert ceramized silica gravel. We tested three treatments with three replicates each: cooling (Co; white gravel), warming (W; black gravel), mix (M; black and white 4:1 gravel) and control (C; bare soil). An automated soil respiration system measured continuously total soil CO2 efflux across all the year and heterotrophic respiration after sowing in root exclusion subplots. Additionally, soil temperature profiles (0, 2.5, 5 and 10 cm depth), soil water content (between 5 and 10 cm depth) were monitored in each plot. After sowing, soybean phenological phases were periodically assessed and final yield was measured in each plot. Results showed a significant change in upper soil temperature between gravel application and canopy closure (maximum of + 5.8 °C and - 6.8 °C in the warming and cooling treatments, respectively). However, warming had only a transient effect on soil respiration (increase) before sowing. Thereafter, as soon as fresh organic matter availability decreased, soil respiration rate decreased and annual budget was not significantly different

  14. Winter warming as an important co-driver for Betula nana growth in western Greenland during the past century

    PubMed Central

    Hollesen, Jørgen; Buchwal, Agata; Rachlewicz, Grzegorz; Hansen, Birger U; Hansen, Marc O; Stecher, Ole; Elberling, Bo

    2015-01-01

    Growing season conditions are widely recognized as the main driver for tundra shrub radial growth, but the effects of winter warming and snow remain an open question. Here, we present a more than 100 years long Betula nana ring-width chronology from Disko Island in western Greenland that demonstrates a highly significant and positive growth response to both summer and winter air temperatures during the past century. The importance of winter temperatures for Betula nana growth is especially pronounced during the periods from 1910–1930 to 1990–2011 that were dominated by significant winter warming. To explain the strong winter importance on growth, we assessed the importance of different environmental factors using site-specific measurements from 1991 to 2011 of soil temperatures, sea ice coverage, precipitation and snow depths. The results show a strong positive growth response to the amount of thawing and growing degree-days as well as to winter and spring soil temperatures. In addition to these direct effects, a strong negative growth response to sea ice extent was identified, indicating a possible link between local sea ice conditions, local climate variations and Betula nana growth rates. Data also reveal a clear shift within the last 20 years from a period with thick snow depths (1991–1996) and a positive effect on Betula nana radial growth, to a period (1997–2011) with generally very shallow snow depths and no significant growth response towards snow. During this period, winter and spring soil temperatures have increased significantly suggesting that the most recent increase in Betula nana radial growth is primarily triggered by warmer winter and spring air temperatures causing earlier snowmelt that allows the soils to drain and warm quicker. The presented results may help to explain the recently observed ‘greening of the Arctic’ which may further accelerate in future years due to both direct and indirect effects of winter warming. PMID:25788025

  15. Is the intensification of precipitation extremes with global warming better detected at hourly than daily resolutions?

    NASA Astrophysics Data System (ADS)

    Barbero, R.; Fowler, H. J.; Lenderink, G.; Blenkinsop, S.

    2017-01-01

    Although it has been documented that daily precipitation extremes are increasing worldwide, faster increases may be expected for subdaily extremes. Here after a careful quality control procedure, we compared trends in hourly and daily precipitation extremes using a large network of stations across the United States (U.S.) within the 1950-2011 period. A greater number of significant increasing trends in annual and seasonal maximum precipitation were detected from daily extremes, with the primary exception of wintertime. Our results also show that the mean percentage change in annual maximum daily precipitation across the U.S. per global warming degree is 6.9% °C-1 (in agreement with the Clausius-Clapeyron rate) while lower sensitivities were observed for hourly extremes, suggesting that changes in the magnitude of subdaily extremes in response to global warming emerge more slowly than those for daily extremes in the climate record.

  16. Are Stronger North-Atlantic Southwesterlies Forcing to the Late Winter Warming in Europe?

    NASA Technical Reports Server (NTRS)

    Otterman, J.; Atlas, Robert; Chou, S.-H.; Jusem, J. C.; Pielke, R. A., Sr.; Chase, T. N.; Rogers, J.; Russell, G. L.; Schubert, S. D.; Sud, Y. C.

    2001-01-01

    We examine a possible mechanism leading to late-winter warming and thus to an early spring in Europe. From the NCEP Reanalysis, we extract for the years 1948-1999 ocean-surface winds over the eastern North Atlantic, and air temperatures at the surface, T(sub s), and at the 500 mb level, T(sub 500), in late-winter and spring. T(sub s) is extracted at six European locations, all at 50.5 N, ranging in longitude from 1.9 E (northeastern France) to 26.2 E (Ukraine). To quantify the advection of maritime air into Europe, we evaluate for 3-pentad groups the Index I(sub na) of the southwesterlies at 45 N; 20 W: I(sub na) is the average wind speed at this point if the direction is from the quadrant 180-270 deg (when the direction is different, the contribution counts as zero). In late winter correlations C(sub it) between the Index I(sub na) and the temperature T(sub s) are substantial, up to the 0.6 level, in western Europe (but weaker correlations for Poland and Ukraine). C(sub it) drops sharply by mid-March, taking occasionally negative values subsequently. This drop in C(sub it) indicates that maritime air advection is no longer associated closely with the surface-air warming, the role of immolation becomes important, and thus the drop in C(sub it) marks the arrival of spring. Correlations C(sub i delta) between I(sub na) and our lapse-rate parameter delta, the difference between T(sub s) and T(sub 500), indicate that the flow of warm maritime-air from the North Atlantic into this 'corridor' at 50.5 N is predominantly at low tropospheric level. By computing the best linear fit to I(sub na) and T(sub s), the trends for the period 1948-1999 are evaluated. The trends are appreciable in the second half of February and the first half of March. Our 3-pentad analysis points to the interval from mid-February to mid-March as the end-of-winter period in which the southwesterlies over the eastern North Atlantic become stronger and the surface-air temperatures in Europe rise

  17. Atmospheric response to Indian Ocean Dipole forcing: changes of Southeast China winter precipitation under global warming

    NASA Astrophysics Data System (ADS)

    Zhang, Ling; Sielmann, Frank; Fraedrich, Klaus; Zhi, Xiefei

    2016-05-01

    To investigate the relationship between autumn Indian Ocean Dipole (IOD) events and the subsequent winter precipitation in Southeast China (SEC), observed fields of monthly precipitation, sea surface temperature (SST) and atmospheric circulation are subjected to a running and a maximum correlation analysis. The results show a significant change of the relevance of IOD for the early modulation of SEC winter precipitation in the 1980s. After 1980, positive correlations suggest prolonged atmospheric responses to IOD forcing, which are linked to an abnormal moisture supply initiated in autumn and extended into the subsequent winter. Under global warming two modulating factors are relevant: (1) an increase of the static stability has been observed suppressing vertical heat and momentum transports; (2) a positive (mid-level) cloud-radiation feedback jointly with the associated latent heating (apparent moisture sink Q2) explains the prolongation of positive as well as negative SST anomalies by conserving the heating (apparent heat source Q1) in the coupled atmosphere-ocean system. During the positive IOD events in fall (after 1980) the dipole heating anomalies in the middle and lower troposphere over the tropical Indian Ocean are prolonged to winter by a positive mid-level cloud-radiative feedback with latent heat release. Subsequently, thermal adaptation leads to an anticyclonic anomaly over Eastern India overlying the anomalous cooling SST of the tropical Eastern Indian Ocean enhancing the moisture flow from the tropical Indian Ocean through the Bay of Bengal into South China, following the northwestern boundary of the anticyclonic circulation anomaly over east India, thereby favoring abundant precipitation in SEC.

  18. Atmospheric response to Indian Ocean Dipole forcing: changes of Southeast China winter precipitation under global warming

    NASA Astrophysics Data System (ADS)

    Zhang, Ling; Sielmann, Frank; Fraedrich, Klaus; Zhi, Xiefei

    2017-03-01

    To investigate the relationship between autumn Indian Ocean Dipole (IOD) events and the subsequent winter precipitation in Southeast China (SEC), observed fields of monthly precipitation, sea surface temperature (SST) and atmospheric circulation are subjected to a running and a maximum correlation analysis. The results show a significant change of the relevance of IOD for the early modulation of SEC winter precipitation in the 1980s. After 1980, positive correlations suggest prolonged atmospheric responses to IOD forcing, which are linked to an abnormal moisture supply initiated in autumn and extended into the subsequent winter. Under global warming two modulating factors are relevant: (1) an increase of the static stability has been observed suppressing vertical heat and momentum transports; (2) a positive (mid-level) cloud-radiation feedback jointly with the associated latent heating (apparent moisture sink Q2) explains the prolongation of positive as well as negative SST anomalies by conserving the heating (apparent heat source Q1) in the coupled atmosphere-ocean system. During the positive IOD events in fall (after 1980) the dipole heating anomalies in the middle and lower troposphere over the tropical Indian Ocean are prolonged to winter by a positive mid-level cloud-radiative feedback with latent heat release. Subsequently, thermal adaptation leads to an anticyclonic anomaly over Eastern India overlying the anomalous cooling SST of the tropical Eastern Indian Ocean enhancing the moisture flow from the tropical Indian Ocean through the Bay of Bengal into South China, following the northwestern boundary of the anticyclonic circulation anomaly over east India, thereby favoring abundant precipitation in SEC.

  19. Winter warming facilitates range expansion: cold tolerance of the butterfly Atalopedes campestris.

    PubMed

    Crozier, Lisa

    2003-05-01

    Our ability to predict ecological and evolutionary responses to climate change requires an understanding of the mechanistic links between climate and range limits. The warming trend over the past half-century has generated numerous opportunities to develop much-needed case studies of these links. Species that are only limited by climatic factors are likely to shift range quickly during periods of warming. Such species directly impact recipient communities and indicate trends that will become more widespread. Because minimum temperature (T (min)) is rising at twice the rate of maximum temperature, species with this range-limiting factor may be especially responsive to global warming. In this study, I test the hypothesis that rising T (min) has directly affected the range of a skipper butterfly. Atalopedes campestris has moved northward rapidly this century, recently colonizing eastern Washington where January T (min) has risen 3 degrees C in 50 years. The results show that: 1. A. campestris' range lies completely within the -4 degrees C January average minimum isotherm, and that recently colonized areas were below this threshold earlier this century. 2. In acute cold stress experiments, -4 to -7 degrees C proved to be a critical thermal limit: median supercooling point was -6.3 degrees C, and minimum lethal temperature (LT50 with 12-h exposure) was -5.7 degrees C. 3. In chronic cold stress experiments, survivorship declined sharply in diurnally fluctuating thermal regimes typical of the current range edge. High mortality occurred under constant 0 degrees C conditions as well as in fluctuating regimes, implying that thermal insulation from snow would not protect A. campestris. 4. There was no evidence of evolution in cold tolerance at the range margin, despite strong selection. Thus, winter warming was apparently a prerequisite for the range expansion. Characteristics of this species that seem to be associated with its rapid response are that it is an opportunistic

  20. Climate model simulation of winter warming and summer cooling following the 1991 Mount Pinatubo volcanic eruption

    NASA Astrophysics Data System (ADS)

    Kirchner, Ingo; Stenchikov, Georgiy L.; Graf, Hans-F.; Robock, Alan; AntuñA, Juan Carlos

    1999-08-01

    We simulate climate change for the 2-year period following the eruption of Mount Pinatubo in the Philippines on June 15, 1991, with the ECHAM4 general circulation model (GCM). The model was forced by realistic aerosol spatial-time distributions and spectral radiative characteristics calculated using Stratospheric Aerosol and Gas Experiment II extinctions and Upper Atmosphere Research Satellite-retrieved effective radii. We calculate statistical ensembles of GCM simulations with and without volcanic aerosols for 2 years after the eruption for three different sea surface temperatures (SSTs): climatological SST, El Niño-type SST of 1991-1993, and La Niña-type SST of 1984-1986. We performed detailed comparisons of calculated fields with observations. We analyzed the atmospheric response to Pinatubo radiative forcing and the ability of the GCM to reproduce it with different SSTs. The temperature of the tropical lower stratosphere increased by 4 K because of aerosol absorption of terrestrial longwave and solar near-infrared radiation. The heating is larger than observed, but that is because in this simulation we did not account for quasi-biennial oscillation (QBO) cooling and the cooling effects of volcanically induced ozone depletion. We estimated that both QBO and ozone depletion decrease the stratospheric temperature by about 2 K. The remaining 2 K stratospheric warming is in good agreement with observations. By comparing the runs with the Pinatubo aerosol forcing with those with no aerosols, we find that the model calculates a general cooling of the global troposphere, but with a clear winter warming pattern of surface air temperature over Northern Hemisphere continents. This pattern is consistent with the observed temperature patterns. The stratospheric heating and tropospheric summer cooling are directly caused by aerosol radiative effects, but the winter warming is indirect, produced by dynamical responses to the enhanced stratospheric latitudinal temperature

  1. Dynamic characteristics of atmospheric planetary waves during stratospheric warmings in winter 2008

    NASA Astrophysics Data System (ADS)

    Chernigovskaya, Marina; Medvedev, Andrey; Tolstikov, Maxim; Medvedeva, Irina; Ratovsky, Konstantin

    2010-05-01

    The wave mechanism of energy transfer is quite significant in transferring energy in the Earth's atmosphere. Atmospheric internal waves of different spatial and temporal scales (including 1-30-day planetary waves) transfer a great deal of kinetic energy from the troposphere and stratosphere to higher atmospheric layers. As deduced from experimental data, systems of strong zonal stratospheric winds prevent penetration of planetary waves from the troposphere to the upper atmosphere (mesosphere and thermosphere), but the part of their energy reaches the upper atmosphere. Planetary waves are in many respects associated with such interesting phenomena in the Earth's stratosphere as sudden winter stratospheric warmings (SSW), observed almost every winter and characterized by geographical nonuniformity. High concentration of stratospheric warming centers is typical of the Asian region of Russia. We examined dynamic characteristics of atmospheric planetary waves observed in the Asian region of Russia in the longitudinal sector of ~80-125°E during stratospheric warmings in winter 2008. Satellite data on vertical temperature distribution obtained by the Microwave Limb Sounder (MLS) aboard the spacecraft EOS Aura and Irkutsk digisonde DPS-4 data were used. It has been established that pronounced wave-like temperature disturbances with characteristic periods of 10-14 days were observed in the Asian region of Russia in the sector of ~80-125°E and 40-64°N over a height range of 20-90 km during development of the SSW in January-February 2008. Revealed here is a high correlation between temperature disturbances and the minimum frequency of reflection in the Irkutsk digisonde DPS-4 ionograms. This paper offers a method for investigating characteristics of propagation of long-term temperature disturbances by a cross-correlation analysis. This method consists in determining delays between disturbances observed at different points and in deriving a system of linear equations for

  2. Extinction of an introduced warm-climate alien species, Xenopus laevis, by extreme weather events.

    PubMed

    Tinsley, Richard C; Stott, Lucy C; Viney, Mark E; Mable, Barbara K; Tinsley, Matthew C

    Invasive, non-native species represent a major threat to biodiversity worldwide. The African amphibian Xenopus laevis is widely regarded as an invasive species and a threat to local faunas. Populations originating at the Western Cape, South Africa, have been introduced on four continents, mostly in areas with a similar Mediterranean climate. Some introduced populations are also established in cooler environments where persistence for many decades suggests a capacity for long-term adaptation. In these cases, recent climate warming might enhance invasion ability, favouring range expansion, population growth and negative effects on native faunas. In the cool temperate UK, populations have been established for about 50 years in Wales and for an unknown period, probably >20 years, in England (Lincolnshire). Our field studies over 30 and 10 years, respectively, show that in favourable conditions there may be good recruitment, fast individual growth rates and large body size; maximum longevity exceeds 23 years. Nevertheless, areas of distribution remained limited, with numbers <500 in each population. In 2010, only a single individual was captured at each locality and further searching failed to record any others in repeated sampling up to 2014. We conclude that both populations are now extinct. The winters of 2009-2010 and 2010-2011 experienced extreme cold and drought (December 2010 was the coldest in 120 years and the third driest in 100 years). The extinction of X. laevis in these areas indicates that even relatively long-established alien species remain vulnerable to rare extreme weather conditions.

  3. The role of land use change in the recent warming of daily extreme temperatures

    NASA Astrophysics Data System (ADS)

    Christidis, Nikolaos; Stott, Peter A.; Hegerl, Gabriele C.; Betts, Richard A.

    2013-02-01

    Abstract Understanding how temperature <span class="hlt">extremes</span> respond in a climate forced by human activity is of great importance, as <span class="hlt">extreme</span> temperatures are detrimental to health and often responsible for mortality increases. While previous detection and attribution studies demonstrated a significant human influence on the recent <span class="hlt">warming</span> of daily <span class="hlt">extremes</span>, contributions of individual anthropogenic forcings like changes in land use have not yet been investigated in such studies. Here we apply an optimal fingerprinting technique to data from observations and experiments with a new earth system model to examine whether changing land use has led to detectable changes in daily <span class="hlt">extreme</span> temperatures on a quasi-global scale. We find that loss of trees and increase of grassland since preindustrial times has caused an overall cooling trend in both mean and <span class="hlt">extreme</span> temperatures which is detectable in the observed changes of <span class="hlt">warm</span> but not cold <span class="hlt">extremes</span>. The <span class="hlt">warming</span> in both mean and <span class="hlt">extreme</span> temperatures due to anthropogenic forcings other than land use is detected in all cases, whereas the weaker effect of natural climatic forcings is not detected in any. This is the first formal attribution of observed climatic changes to changing land use, suggesting further investigations are justified, particularly in studies of <span class="hlt">warm</span> <span class="hlt">extremes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMGC21I..07C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMGC21I..07C"><span id="translatedtitle">A Global Analysis of the Link between Soil Moisture Dynamics and <span class="hlt">Warm</span> <span class="hlt">Extremes</span>.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Casagrande, E.; Kondapalli, N. K.; Mueller, B.; Miralles, D. G.; Molini, A.</p> <p>2014-12-01</p> <p>Under future climatic scenarios long-lasting <span class="hlt">warm</span> <span class="hlt">extremes</span>, such as heat waves, are expected to become more intense, persistent and frequent for both temperate and arid regions, resulting in diverse but nonetheless significant impacts for the human health, sustainable development and economy of these regions. As the underlying processes responsible for triggering and sustaining <span class="hlt">warm</span> <span class="hlt">extremes</span> are <span class="hlt">extremely</span> variegate and yet not well understood, the occurrence of <span class="hlt">extreme</span> events such heat waves and prolonged droughts results exceedingly difficult to predict and model. Major uncertainties arise from the fact that <span class="hlt">warm</span> <span class="hlt">extremes</span> mainly derive from the interplay of large-scale atmospheric processes and local feedbacks operating across very different spatial and temporal scales, and are characterized by several thresholds, limiting factors and non-linearities determining their deviation from the "classical" <span class="hlt">extreme</span>-value theory.In this study we explore - from a global point of view - the role of local and synoptic dynamical components in initiating <span class="hlt">warm</span> <span class="hlt">extremes</span> and in determining their spatial and temporal clustering. Previous studies have already highlighted the role of large negative soil moisture anomalies in causing and sustaining long periods of dry and hot weather. For this reason we propose here a novel approach to the characterization of <span class="hlt">warm</span> <span class="hlt">extremes</span>, based on the conditioning of traditional air temperature quintile statistics to antecedent soil moisture conditions. Case studies from different climatic regimes are shown in order to prove the major and varied role of antecedent soil moisture conditions across the different regions of the world. In addition, we also investigate the connection between regional climate features and large-scale dynamics during <span class="hlt">warm</span> <span class="hlt">extremes</span> by the joint usage of classical diagnostic analysis and novel statistics for the detection of cross-scale interactions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017OcSci..13...47B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017OcSci..13...47B"><span id="translatedtitle">Changes in <span class="hlt">extreme</span> regional sea level under global <span class="hlt">warming</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brunnabend, S.-E.; Dijkstra, H. A.; Kliphuis, M. A.; Bal, H. E.; Seinstra, F.; van Werkhoven, B.; Maassen, J.; van Meersbergen, M.</p> <p>2017-01-01</p> <p>An important contribution to future changes in regional sea level <span class="hlt">extremes</span> is due to the changes in intrinsic ocean variability, in particular ocean eddies. Here, we study a scenario of future dynamic sea level (DSL) <span class="hlt">extremes</span> using a high-resolution version of the Parallel Ocean Program and generalized <span class="hlt">extreme</span> value theory. This model is forced with atmospheric fluxes from a coupled climate model which has been integrated under the IPCC-SRES-A1B scenario over the period 2000-2100. Changes in 10-year return time DSL <span class="hlt">extremes</span> are very inhomogeneous over the globe and are related to changes in ocean currents and corresponding regional shifts in ocean eddy pathways. In this scenario, several regions in the North Atlantic experience an increase in mean DSL of up to 0.4 m over the period 2000-2100. DSL <span class="hlt">extremes</span> with a 10-year return time increase up to 0.2 m with largest values in the northern and eastern Atlantic.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014GeoRL..41.8847A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014GeoRL..41.8847A"><span id="translatedtitle">Global <span class="hlt">warming</span> and changes in risk of concurrent climate <span class="hlt">extremes</span>: Insights from the 2014 California drought</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>AghaKouchak, Amir; Cheng, Linyin; Mazdiyasni, Omid; Farahmand, Alireza</p> <p>2014-12-01</p> <p>Global <span class="hlt">warming</span> and the associated rise in <span class="hlt">extreme</span> temperatures substantially increase the chance of concurrent droughts and heat waves. The 2014 California drought is an archetype of an event characterized by not only low precipitation but also <span class="hlt">extreme</span> high temperatures. From the raging wildfires, to record low storage levels and snowpack conditions, the impacts of this event can be felt throughout California. Wintertime water shortages worry decision-makers the most because it is the season to build up water supplies for the rest of the year. Here we show that the traditional univariate risk assessment methods based on precipitation condition may substantially underestimate the risk of <span class="hlt">extreme</span> events such as the 2014 California drought because of ignoring the effects of temperature. We argue that a multivariate viewpoint is necessary for assessing risk of <span class="hlt">extreme</span> events, especially in a <span class="hlt">warming</span> climate. This study discusses a methodology for assessing the risk of concurrent <span class="hlt">extremes</span> such as droughts and <span class="hlt">extreme</span> temperatures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1133221','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1133221"><span id="translatedtitle">The Robust Dynamical Contribution to Precipitation <span class="hlt">Extremes</span> in Idealized <span class="hlt">Warming</span> Simulations across Model Resolutions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Lu, Jian; Leung, Lai-Yung R.; Yang, Qing; Chen, Gang; Collins, William D.; Li, Fuyu; Hou, Zhangshuan; Feng, Xuelei</p> <p>2014-04-28</p> <p>The impact of the circulation shift under climate <span class="hlt">warming</span> on the distribution of precipitation <span class="hlt">extremes</span> and the associated sensitivity to model resolution are investigated using the aquaplanet Community Atmosphere Model CAM3. The response of the probability density function of the precipitation to a uniform SST <span class="hlt">warming</span> can be interpreted as superimposition of a dynamically induced poleward shift and a thermodynamically induced upward shift toward higher intensities, which give rise to manyfold increase in the frequency of the most <span class="hlt">extreme</span> categories of the precipitation events at the poleward side of the midlatitude storm track. Meanwhile, the thermodynamic contribution to the intensification of the precipitation <span class="hlt">extremes</span> is substantially less than expected from the Clausius-Clapeyron relation, implicative of significant change in the vertical structure of the precipitation processes. While coarser resolutions underestimate the dynamical contribution to the increase of precipitation <span class="hlt">extremes</span>, a modest increase of the equator-to-pole SST <span class="hlt">warming</span> gradient can have a significant opposite effect.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016MAP...tmp...51D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016MAP...tmp...51D"><span id="translatedtitle"><span class="hlt">Warm</span> pool/cold tongue El Niño and Indian <span class="hlt">winter</span> Monsoon</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dimri, A. P.</p> <p>2016-08-01</p> <p>In view of the recent global changes in the hydrological, glaciological, agricultural, socio-economic studies, etc., particularly, over the northern Indian region, Indian <span class="hlt">winter</span> (December, January, February—DJF) monsoon (IWM) has important role. Geographical positioning of the Indian subcontinent having mighty Himalayas in the north and surrounding ocean in the south makes assessment of IWM important and interesting to study. During IWM, the western Himalayas (WH) receives almost one-third of annual precipitation due to eastward moving extratropical cyclonic storms, western disturbances (WDs), embedded within the large scale subtropical westerly jet (SWJ). In addition, IWM is found to be in phase with the El Niño—Southern Oscillation (ENSO). With reference to the recent decade's finding of having different phases of El Niño- <span class="hlt">warm</span> pool (WP) and cold tongue (CT)—it is imperative to see how these phases affect IWM. In the present study a simple mechanism between IWM with different phases of these El Niño and their relationship is studied and deliberated upon. WP and CT El Niño phase composites are prepared and their corresponding role in tandem with IWM is provided. It is found that during WP (CP) El Niño phase WH (foothill of the Indian Himalayan) region receives higher amount of <span class="hlt">winter</span> precipitation. It is attributed to the fact that equatorial central Pacific <span class="hlt">warming</span> makes more conducive proposition for intensification of the WDs and thus associated higher precipitation over western part of the Indian Himalayas. Northward shift of confluence over northern Atlantic region during WP El Niño phase dampens the SWJ leading to longer residence time for weather events—WDs—over the WH region. In addition, strengthening of Hadley cell leads to higher northward transport of moisture from the Indian Ocean region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007Icar..186...97M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007Icar..186...97M"><span id="translatedtitle"><span class="hlt">Winter</span> polar <span class="hlt">warmings</span> and the meridional transport on Mars simulated with a general circulation model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Medvedev, Alexander S.; Hartogh, Paul</p> <p>2007-01-01</p> <p><span class="hlt">Winter</span> polar <span class="hlt">warmings</span> in the middle atmosphere of Mars occur due to the adiabatic heating associated with the downward branch of the cross-equatorial meridional circulation. Thus, they are the manifestation of the global meridional transport rather than of local radiative effects. We report on a series of numerical experiments with a recently developed general circulation model of the martian atmosphere to examine the relative roles of the mechanical and thermal forcing in the meridional transport. The experiments were focused on answering the question of whether the martian circulation is consistent with the thermally driven nearly inviscid Hadley cell, as was pointed out by some previous studies, or it is forced mainly by zonally asymmetric eddies. It is demonstrated that, under realistic conditions in the middle atmosphere, the meridional transport is maintained primarily by dissipating large-scale planetary waves and solar tides. This mechanism is similar to the "extratropical pump" in the middle atmosphere on Earth. Only in the run with artificially weak zonal disturbances, was the circulation reminiscent of thermally induced Hadley cells. In the experiment with an imposed dust storm, the modified atmospheric refraction changes the vertical propagation of the eddies. As the result, the Eliassen-Palm fluxes convergence increases in high <span class="hlt">winter</span> latitudes of the middle atmosphere, the meridional transport gets stronger, and the polar temperature rises. Additional numerical experiments demonstrated that insufficient model resolution, increased numerical dissipation, and, especially, neglect of non-LTE effects for the 15 μm CO 2 band could weaken the meridional transport and the magnitude of polar <span class="hlt">warmings</span> in GCMs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2871880','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2871880"><span id="translatedtitle">Nectar yeasts <span class="hlt">warm</span> the flowers of a <span class="hlt">winter</span>-blooming plant</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Herrera, Carlos M.; Pozo, María I.</p> <p>2010-01-01</p> <p>Yeasts are ubiquitous in terrestrial and aquatic microbiota, yet their ecological functionality remains relatively unexplored in comparison with other micro-organisms. This paper formulates and tests the novel hypothesis that heat produced by the sugar catabolism of yeast populations inhabiting floral nectar can increase the temperature of floral nectar and, more generally, modify the within-flower thermal microenvironment. Two field experiments were designed to test this hypothesis for the <span class="hlt">winter</span>-blooming herb Helleborus foetidus (Ranunculaceae). In experiment 1, the effect of yeasts on the within-flower thermal environment was tested by excluding them from flowers, while in experiment 2 the test involved artificial inoculation of virgin flowers with yeasts. Nectary temperature (Tnect), within-flower air temperature (Tflow) and external air temperature (Tair) were measured on experimental and control flowers in both experiments. Experimental exclusion of yeasts from the nectaries significantly reduced, and experimental addition of yeasts significantly increased, the temperature excess of nectaries (ΔTnect = Tnect − Tair) and the air space inside flowers in relation to the air just outside the flowers. In non-experimental flowers exposed to natural pollinator visitation, ΔTnect was linearly related to log yeast cell density in nectar, and reached +6°C in nectaries with the densest yeast populations. The <span class="hlt">warming</span> effect of nectar-dwelling yeasts documented in this study suggests novel ecological mechanisms potentially linking nectarivorous microbes with <span class="hlt">winter</span>-blooming plants and their insect pollinators. PMID:20147331</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.7917S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.7917S"><span id="translatedtitle">The Northern Hemisphere <span class="hlt">winter</span> stationary wave response to global <span class="hlt">warming</span> in CMIP5</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Simpson, Isla; Seager, Richard; Ting, Mingfang; Shaw, Tiffany</p> <p>2015-04-01</p> <p>During the Northern Hemisphere <span class="hlt">winter</span>, models tend to predict a poleward shifting of the zonal mean mid-latitude westerlies under anthropogenic greenhouse gas emissions. Locally, however, changes in the stationary waves tend to dominate, resulting in considerable deviation from this around the longitude circle, with important implications for regional climate change. Past studies have demonstrated diversity in the stationary wave response to global <span class="hlt">warming</span> and differ in their views of the mechanisms involved in producing it. Here we will explore the stationary wave response to global <span class="hlt">warming</span> in the CMIP5 dataset and demonstrate a strong consensus on a wavenumber 5 stationary wave response with a particular phasing that contributes to hydroclimate change across North America and Europe, such as wetting on the west coast of the USA, drying in the south west USA and drying in the eastern Mediterranean. The mechanisms responsible for producing this multi-model mean response are explored using a stationary wave model. It is demonstrated that, to first order, it is produced by changes in the zonal mean basic state, in agreement with the majority of previous stationary wave modelling studies. The relative importance of different features of this basic state change such as Arctic amplification, enhanced tropical upper tropospheric <span class="hlt">warming</span>, stratospheric cooling and their associated zonal mean zonal wind responses will be explored. Through an understanding of the mechanisms involved in this stationary wave response we can begin to assess our confidence in whether the real world will behave as the models do and understand any diversity among the modelled responses.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5159872','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5159872"><span id="translatedtitle"><span class="hlt">Extreme</span> <span class="hlt">warming</span> challenges sentinel status of kelp forests as indicators of climate change</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Reed, Daniel; Washburn, Libe; Rassweiler, Andrew; Miller, Robert; Bell, Tom; Harrer, Shannon</p> <p>2016-01-01</p> <p>The desire to use sentinel species as early warning indicators of impending climate change effects on entire ecosystems is attractive, but we need to verify that such approaches have sound biological foundations. A recent large-scale <span class="hlt">warming</span> event in the North Pacific Ocean of unprecedented magnitude and duration allowed us to evaluate the sentinel status of giant kelp, a coastal foundation species that thrives in cold, nutrient-rich waters and is considered sensitive to <span class="hlt">warming</span>. Here, we show that giant kelp and the majority of species that associate with it did not presage ecosystem effects of <span class="hlt">extreme</span> <span class="hlt">warming</span> off southern California despite giant kelp's expected vulnerability. Our results challenge the general perception that kelp-dominated systems are highly vulnerable to <span class="hlt">extreme</span> <span class="hlt">warming</span> events and expose the more general risk of relying on supposed sentinel species that are assumed to be very sensitive to climate change. PMID:27958273</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatCo...713757R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatCo...713757R"><span id="translatedtitle"><span class="hlt">Extreme</span> <span class="hlt">warming</span> challenges sentinel status of kelp forests as indicators of climate change</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Reed, Daniel; Washburn, Libe; Rassweiler, Andrew; Miller, Robert; Bell, Tom; Harrer, Shannon</p> <p>2016-12-01</p> <p>The desire to use sentinel species as early warning indicators of impending climate change effects on entire ecosystems is attractive, but we need to verify that such approaches have sound biological foundations. A recent large-scale <span class="hlt">warming</span> event in the North Pacific Ocean of unprecedented magnitude and duration allowed us to evaluate the sentinel status of giant kelp, a coastal foundation species that thrives in cold, nutrient-rich waters and is considered sensitive to <span class="hlt">warming</span>. Here, we show that giant kelp and the majority of species that associate with it did not presage ecosystem effects of <span class="hlt">extreme</span> <span class="hlt">warming</span> off southern California despite giant kelp's expected vulnerability. Our results challenge the general perception that kelp-dominated systems are highly vulnerable to <span class="hlt">extreme</span> <span class="hlt">warming</span> events and expose the more general risk of relying on supposed sentinel species that are assumed to be very sensitive to climate change.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70158672','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70158672"><span id="translatedtitle">Life stage influences the resistance and resilience of black mangrove forests to <span class="hlt">winter</span> climate <span class="hlt">extremes</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>Osland, Michael J.; Day, Richard H.; From, Andrew S.; McCoy, Megan L.; McLeod, Jennie L.; Kelleway, Jeffrey</p> <p>2015-01-01</p> <p>In subtropical coastal wetlands on multiple continents, climate change-induced reductions in the frequency and intensity of freezing temperatures are expected to lead to the expansion of woody plants (i.e., mangrove forests) at the expense of tidal grasslands (i.e., salt marshes). Since some ecosystem goods and services would be affected by mangrove range expansion, there is a need to better understand mangrove sensitivity to freezing temperatures as well as the implications of changing <span class="hlt">winter</span> climate <span class="hlt">extremes</span> for mangrove-salt marsh interactions. In this study, we investigated the following questions: (1) how does plant life stage (i.e., ontogeny) influence the resistance and resilience of black mangrove (Avicennia germinans) forests to freezing temperatures; and (2) how might differential life stage responses to freeze events affect the rate of mangrove expansion and salt marsh displacement due to climate change? To address these questions, we quantified freeze damage and recovery for different life stages (seedling, short tree, and tall tree) following <span class="hlt">extreme</span> <span class="hlt">winter</span> air temperature events that occurred near the northern range limit of A. germinans in North America. We found that life stage affects black mangrove forest resistance and resilience to <span class="hlt">winter</span> climate <span class="hlt">extremes</span> in a nonlinear fashion. Resistance to <span class="hlt">winter</span> climate <span class="hlt">extremes</span> was high for tall A. germinans trees and seedlings, but lowest for short trees. Resilience was highest for tall A. germinans trees. These results suggest the presence of positive feedbacks and indicate that climate-change induced decreases in the frequency and intensity of <span class="hlt">extreme</span> minimum air temperatures could lead to a nonlinear increase in mangrove forest resistance and resilience. This feedback could accelerate future mangrove expansion and salt marsh loss at rates beyond what would be predicted from climate change alone. In general terms, our study highlights the importance of accounting for differential life stage responses and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23874424','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23874424"><span id="translatedtitle">Infrared <span class="hlt">warming</span> reduced <span class="hlt">winter</span> wheat yields and some physiological parameters, which were mitigated by irrigation and worsened by delayed sowing.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Fang, Shibo; Su, Hua; Liu, Wei; Tan, Kaiyan; Ren, Sanxue</p> <p>2013-01-01</p> <p><span class="hlt">Winter</span> wheat has a central role in ensuring the food security and welfare of 1.3 billion people in China. Extensive previous studies have concluded that <span class="hlt">winter</span> wheat yields would decrease with higher temperatures, owing to <span class="hlt">warming</span>-induced soil drying or shortening of phenophase. Temperature in China is predicted to increase by 1-5°C by 2100, which may greatly impact plant production and cause other negative effects. We performed a manipulative field experiment, creating diverse growth regimes for wheat by infrared radiation (IR) <span class="hlt">warming</span> day and night, including IR <span class="hlt">warming</span> only (DW), IR <span class="hlt">warming</span> + delayed sowing dates (DS), IR <span class="hlt">warming</span> + increased irrigation (IW), and a control (CK). The results show that IR <span class="hlt">warming</span> increased daily average wheat canopy and soil temperatures by 2.0°C and 2.3°C, respectively. DW was associated with an advanced maturity of 10 days and yield reduction of 8.2%. IR-<span class="hlt">warming</span> effects on the photosynthetic apparatus of wheat varied with season as well as significant differences were found in the booting stage. DS represented a worsened situation, lowering yield per plant by 16.4%, with a significant decline in aboveground biomass and functional leaf area. Wheat under DS showed double-peak patterns of diurnal gas exchange during booting stages and, consequently, lower photosynthetic capacity with high transpiration for cooling. Significantly lower actual water use efficiency and intrinsic water use efficiency from jointing to anthesis stages were also found under DS. However, IW had no significant difference from CK, irrespective of yield and photosynthesis. Therefore, we concluded that delayed sowing date may not be a good choice for <span class="hlt">winter</span> wheat, whereas a thoroughly-watered wheat agroecosystem should be promoted in the context of global <span class="hlt">warming</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3706519','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3706519"><span id="translatedtitle">Infrared <span class="hlt">Warming</span> Reduced <span class="hlt">Winter</span> Wheat Yields and Some Physiological Parameters, Which Were Mitigated by Irrigation and Worsened by Delayed Sowing</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, Shibo; Su, Hua; Liu, Wei; Tan, Kaiyan; Ren, Sanxue</p> <p>2013-01-01</p> <p><span class="hlt">Winter</span> wheat has a central role in ensuring the food security and welfare of 1.3 billion people in China. Extensive previous studies have concluded that <span class="hlt">winter</span> wheat yields would decrease with higher temperatures, owing to <span class="hlt">warming</span>-induced soil drying or shortening of phenophase. Temperature in China is predicted to increase by 1–5°C by 2100, which may greatly impact plant production and cause other negative effects. We performed a manipulative field experiment, creating diverse growth regimes for wheat by infrared radiation (IR) <span class="hlt">warming</span> day and night, including IR <span class="hlt">warming</span> only (DW), IR <span class="hlt">warming</span> + delayed sowing dates (DS), IR <span class="hlt">warming</span> + increased irrigation (IW), and a control (CK). The results show that IR <span class="hlt">warming</span> increased daily average wheat canopy and soil temperatures by 2.0°C and 2.3°C, respectively. DW was associated with an advanced maturity of 10 days and yield reduction of 8.2%. IR-<span class="hlt">warming</span> effects on the photosynthetic apparatus of wheat varied with season as well as significant differences were found in the booting stage. DS represented a worsened situation, lowering yield per plant by 16.4%, with a significant decline in aboveground biomass and functional leaf area. Wheat under DS showed double-peak patterns of diurnal gas exchange during booting stages and, consequently, lower photosynthetic capacity with high transpiration for cooling. Significantly lower actual water use efficiency and intrinsic water use efficiency from jointing to anthesis stages were also found under DS. However, IW had no significant difference from CK, irrespective of yield and photosynthesis. Therefore, we concluded that delayed sowing date may not be a good choice for <span class="hlt">winter</span> wheat, whereas a thoroughly-watered wheat agroecosystem should be promoted in the context of global <span class="hlt">warming</span>. PMID:23874424</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.1660Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.1660Z"><span id="translatedtitle">Indirect Radiative <span class="hlt">Warming</span> Effect in the <span class="hlt">Winter</span> and Spring Arctic Associated with Aerosol Pollution from Mid-latitude Regions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhao, Chuanfeng; Garrett, Timothy</p> <p>2016-04-01</p> <p>Different from global cooling effects of aerosols and aerosol-cloud interactions, anthropogenic aerosols from mid-latitude are found to play an increased <span class="hlt">warming</span> effect in the Arctic in later <span class="hlt">winter</span> and early spring. Using four-year (2000-2003) observation of aerosol, cloud and radiation at North Slope of Alaska, it is found that the aerosols can increase cloud droplet effective radius 3 um for fixed liquid water path, and increase cloud thermal emissivity about 0.05-0.08. In other words, aerosols are associated with a <span class="hlt">warming</span> of 1-1.6 degrees (3-5 W/m2) in the Arctic during late <span class="hlt">winter</span> and early spring solely due to their first indirect effect. Further analysis indicates that total aerosol climate effects are even more significant (8-10 W/m2), with about 50% contribution from aerosol first indirect effect and another 50% contribution from complicated feedbacks. It also shows strong seasonal distribution of the aerosol indirect radiative effects, with <span class="hlt">warming</span> effects in seasons other than in summer. However, only the significant <span class="hlt">warming</span> effect in <span class="hlt">winter</span> and spring passes through the significance test. The strong <span class="hlt">warming</span> effect due to aerosol indirect effect could be further strengthened through following feedbacks involving the surface albedo (early ice melting).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMGC44B..05C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMGC44B..05C"><span id="translatedtitle">Has Anthropogenic Global <span class="hlt">Warming</span> in the Arctic Contributed to Colder <span class="hlt">Winter</span> Weather in the Northern Hemisphere Mid-latitudes?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cohen, J. L.; Furtado, J. C.; Barlow, M. A.; Cherry, J. E.; Alexeev, V. A.</p> <p>2012-12-01</p> <p>The global climate models predict that temperatures will <span class="hlt">warm</span> the greatest in <span class="hlt">winter</span> due to a positive feedback of increased greenhouse gases and a diminished and darker cryosphere. Furthermore, current consensus on global climate change predicts <span class="hlt">warming</span> trends over the NH continents during boreal <span class="hlt">winter</span>. However, recent trends in Northern Hemisphere (NH) seasonal surface temperatures diverge from these projections. For the last two decades or so, NH landmasses have experienced significant <span class="hlt">warming</span> trends for all seasons except <span class="hlt">winter</span>, when large-scale cooling trends exist instead. We propose a mechanism linking Arctic <span class="hlt">warming</span> and <span class="hlt">winter</span> continental cooling. Evidence suggests that summer and autumn Arctic <span class="hlt">warming</span> trends are concurrent with increases in high-latitude moisture and an increase in autumnal Eurasian snow cover, which dynamically induces large-scale wintertime cooling. Understanding this counterintuitive response to radiative <span class="hlt">warming</span> of the climate system has the potential to improve climate predictions at seasonal and longer timescales.a) JAS area-averaged (poleward of 60°N) surface temperature anomalies (°C) from NASA MERRA. b) September area-averaged (poleward of 65°N) Arctic Ocean sea ice coverage (fractional area). c) September - October vertically integrated (700-1000 hPa) and area-averaged (poleward of 60°N) specific humidity (kg m-2). d) October mean snow cover areal extent (106 km2) over the Eurasian continent from observations (black) and ensemble-mean from the historical runs of the CMIP5 model output (brown line). e) The DJF average AO index (standardized). Same-coloured dashed lines in a) - e) represent the linear trend in each index. Trends with double asterisk (**) indicate trends are significant at the p < 0.01 level.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25500451','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25500451"><span id="translatedtitle">Responses of the photosynthetic apparatus to <span class="hlt">winter</span> conditions in broadleaved evergreen trees growing in <span class="hlt">warm</span> temperate regions of Japan.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Tanaka, Chizuru; Nakano, Takashi; Yamazaki, Jun-Ya; Maruta, Emiko</p> <p>2015-01-01</p> <p>Photosynthetic characteristics of two broadleaved evergreen trees, Quercus myrsinaefolia and Machilus thunbergii, were compared in autumn and <span class="hlt">winter</span>. The irradiance was similar in both seasons, but the air temperature was lower in <span class="hlt">winter</span>. Under the <span class="hlt">winter</span> conditions, net photosynthesis under natural sunlight (Anet) in both species dropped to 4 μmol CO2 m(-2) s(-1), and the quantum yield of photosystem II (PSII) photochemistry in dark-adapted leaves (Fv/Fm) also dropped to 0.60. In both species the maximum carboxylation rates of Rubisco (V(cmax)) decreased, and the amount of Rubisco increased in <span class="hlt">winter</span>. A decline in chlorophyll (Chl) concentration and an increase in the Chl a/b ratio in <span class="hlt">winter</span> resulted in a reduction in the size of the light-harvesting antennae. From measurements of Chl a fluorescence parameters, both the relative fraction and the energy flux rates of thermal dissipation through other non-photochemical processes were markedly elevated in <span class="hlt">winter</span>. The results indicate that the photosynthetic apparatus in broadleaved evergreen species in <span class="hlt">warm</span> temperate regions responds to <span class="hlt">winter</span> through regulatory mechanisms involving the downregulation of light-harvesting and photosynthesis coupled with increased photoprotective thermal energy dissipation to minimize photodamage in <span class="hlt">winter</span>. These mechanisms aid a quick restart of photosynthesis without the development of new leaves in the following spring.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.3515K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.3515K"><span id="translatedtitle">Does <span class="hlt">winter</span> <span class="hlt">warming</span> enhance cold CO2 emission from temperate continental soils?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kurganova, Irina; Lopes de Gerenyu, Valentin; Khoroshaev, Dmitry</p> <p>2016-04-01</p> <p> revealed during the early spring FTC. They corresponded to a rapid thawing of frozen soils due to the customary rise of air temperature at the beginning of March. These CO2 emission pulses during early spring contributed between 43% and 70% to the total cold CO2 fluxes from frozen soils ('Ref" and "NoSn" variants). The contribution of spring fluxes from unfrozen soils ("NoFr" treatment) to the total cold CO2 emission was about 25%. Our findings produce evidence that <span class="hlt">winter</span> <span class="hlt">warming</span> in temperate continental regions has resulted in a reduction in the permanent snow pack, an increase in the frequency of freezing-thawing events and can be followed by a prolongation of the period when soils remain frozen. Soil respiration fluxes were greatly reduced owing to an increase in frost stress both for plants and for the soil microbial community. Therefore, <span class="hlt">winter</span> <span class="hlt">warming</span> in temperate continental areas decreases cold CO2 emissions from soils into the atmosphere and is expected thereby to lead to a rise in the annual carbon sink in ecosystems. This study was supported by the Russian Science Foundation (14-14-00625) and the Russian Foundation for Basic Research (project 15-04-05156a).</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('http://adsabs.harvard.edu/abs/2016ClDy..tmp..297L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ClDy..tmp..297L"><span id="translatedtitle">How predictable is the <span class="hlt">winter</span> <span class="hlt">extremely</span> cold days over temperate East Asia?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Luo, Xiao; Wang, Bin</p> <p>2016-07-01</p> <p>Skillful seasonal prediction of the number of <span class="hlt">extremely</span> cold day (NECD) has considerable benefits for climate risk management and economic planning. Yet, predictability of NECD associated with East Asia <span class="hlt">winter</span> monsoon remains largely unexplored. The present work estimates the NECD predictability in temperate East Asia (TEA, 30°-50°N, 110°-140°E) where the current dynamical models exhibit limited prediction skill. We show that about 50 % of the total variance of the NECD in TEA region is likely predictable, which is estimated by using a physics-based empirical (P-E) model with three consequential autumn predictors, i.e., developing El Niño/La Niña, Eurasian Arctic Ocean temperature anomalies, and geopotential height anomalies over northern and eastern Asia. We find that the barotropic geopotential height anomaly over Asia can persist from autumn to <span class="hlt">winter</span>, thereby serving as a predictor for <span class="hlt">winter</span> NECD. Further analysis reveals that the sources of the NECD predictability and the physical basis for prediction of NECD are essentially the same as those for prediction of <span class="hlt">winter</span> mean temperature over the same region. This finding implies that forecasting seasonal mean temperature can provide useful information for prediction of <span class="hlt">extreme</span> cold events. Interpretation of the lead-lag linkages between the three predictors and the predictand is provided for stimulating further studies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22705063','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22705063"><span id="translatedtitle">Disease transmission in an <span class="hlt">extreme</span> environment: nematode parasites infect reindeer during the Arctic <span class="hlt">winter</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Carlsson, Anja M; Justin Irvine, R; Wilson, Kenneth; Piertney, Stuart B; Halvorsen, Odd; Coulson, Stephen J; Stien, Audun; Albon, Steve D</p> <p>2012-07-01</p> <p>Parasitic nematodes are found in almost all wild vertebrate populations but few studies have investigated these host-parasite relationships in the wild. For parasites with free-living stages, the external environment has a major influence on life-history traits, and development and survival is generally low at sub-zero temperatures. For reindeer that inhabit the high Arctic archipelago of Svalbard, parasite transmission is expected to occur in the summer, due to the <span class="hlt">extreme</span> environmental conditions and the reduced food intake by the host in <span class="hlt">winter</span>. Here we show experimentally that, contrary to most parasitic nematodes, Marshallagia marshalli of Svalbard reindeer is transmitted during the Arctic <span class="hlt">winter</span>. <span class="hlt">Winter</span> transmission was demonstrated by removing parasites in the autumn, using a novel delayed-release anthelmintic bolus, and estimating re-infection rates in reindeer sampled in October, February and April. Larval stages of nematodes were identified using molecular tools, whereas adult stages were identified using microscopy. The abundance of M. marshalli adult worms and L4s increased significantly from October to April, indicating that reindeer were being infected with L3s from the pasture throughout the <span class="hlt">winter</span>. To our knowledge, this study is the first to experimentally demonstrate over-<span class="hlt">winter</span> transmission of a gastro-intestinal nematode parasite in a wild animal. Potential mechanisms associated with this unusual transmission strategy are discussed in light of our knowledge of the life-history traits of this parasite.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25294217','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25294217"><span id="translatedtitle">Reproducing under a <span class="hlt">warming</span> climate: long <span class="hlt">winter</span> flowering and extended flower longevity in the only Mediterranean and maritime Primula.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Aronne, G; Buonanno, M; De Micco, V</p> <p>2015-03-01</p> <p>Under the pressure of global <span class="hlt">warming</span>, general expectations of species migration and evolution of adaptive traits should always be confirmed with species-specific studies. Within this framework, some species can be used as study systems to predict possible consequences of global <span class="hlt">warming</span> also on other relatives. Unlike its mountain congeneric, Primula palinuri Petagn. has endured all the climatic fluctuations since the Pleistocene, while surviving on Mediterranean coastal cliffs. The aim of this work was to investigate the possible evolution of reproductive biological and ecological traits in P. palinuri adaptation to a warmer environment. Data showed that flowering starts in mid-<span class="hlt">winter</span>; single flowers remain open for over a month, changing from pendulous to erect. The number of insects visiting flowers of P. palinuri increases during the flowering season, and pollination reduces flower longevity. Overall, the best pollen performances, in terms of viability and germinability, occur at <span class="hlt">winter</span> temperatures, while pollinator activity prolongs flowering until spring. Moreover, extended longevity of single flowers optimises reproductive success. Both phenotypic plasticity and selective processes might have occurred in P. palinuri. However, we found that reproductive traits of the only Mediterranean Primula remain more associated with cold mountain habitats than <span class="hlt">warm</span> coastal cliffs. Given the rapid trend of climate <span class="hlt">warming</span>, migration and new adaptive processes in P. palinuri are unlikely. Response to past climate <span class="hlt">warming</span> of P. palinuri provides useful indications for future scenarios in other Primula species.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014CSR....91..211L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014CSR....91..211L"><span id="translatedtitle">Effects of Cardamom Mountains on the formation of the <span class="hlt">winter</span> <span class="hlt">warm</span> pool in the gulf of Thailand</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Jiaxun; Zhang, Ren; Ling, Zheng; Bo, Wenbo; Liu, Yuhong</p> <p>2014-12-01</p> <p>A small-scale <span class="hlt">winter</span> <span class="hlt">warm</span> pool covering an area of about 75,000 km2 in the Gulf of Thailand (GoT) was uncovered using a suite of new high resolution satellite observations and historical in situ data. The core temperature of this <span class="hlt">warm</span> pool is about 0.5-0.8 °C higher than that of the surroundings. The <span class="hlt">warm</span> pool exists from the surface to the bottom of the sea. It forms in the first ten days of November, evolves to a mature stage from the mid-November to the early in January, and begins to decay in the mid-January. Our results show the formation of the <span class="hlt">warm</span> pool is well correlated with the Cardamom Mountains on the Indo-China Peninsula. Due to the orographic effect of Cardamom Mountains, the low surface latent heat flux resulting from the wind wake leads to the formation of the <span class="hlt">warm</span> pool in the sea. The interannual variability of the <span class="hlt">warm</span> pool is affected by the El Niño-Southern Oscillation (ENSO) by modulating the strength of northeast monsoon each year. The <span class="hlt">warm</span> pool has a possible implication for the marine ecosystem in the GoT.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25255853','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25255853"><span id="translatedtitle">Are <span class="hlt">winter</span>-active species vulnerable to climate <span class="hlt">warming</span>? A case study with the wintergreen terrestrial orchid, Tipularia discolor.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Marchin, Renée M; Dunn, Robert R; Hoffmann, William A</p> <p>2014-12-01</p> <p>In the eastern United States, <span class="hlt">winter</span> temperature has been increasing nearly twice as fast as summer temperature, but studies of <span class="hlt">warming</span> effects on plants have focused on species that are photosynthetically active in summer. The terrestrial orchid Tipularia discolor is leafless in summer and acquires C primarily in <span class="hlt">winter</span>. The optimum temperature for photosynthesis in T. discolor is higher than the maximum temperature throughout most of its growing season, and therefore growth can be expected to increase with <span class="hlt">warming</span>. Contrary to this hypothesis, experimental <span class="hlt">warming</span> negatively affected reproductive fitness (number of flowering stalks, flowers, fruits) and growth (change in leaf area from 2010 to 2012) in T. discolor. Temperature in June-July was critical for flowering, and mean July temperature greater than 29 °C (i.e., 2.5 °C above ambient) eliminated reproduction. <span class="hlt">Warming</span> of 1.2 °C delayed flowering by an average of 10 days and fruiting by an average of 5 days. <span class="hlt">Warming</span> of 4.4 °C reduced relative growth rates by about 60%, which may have been partially caused by the direct effects of temperature on photosynthesis and respiration. <span class="hlt">Warming</span> indirectly increased vapor pressure deficit (VPD) by 0.2-0.5 kPa, and leaf-to-air VPD over 1.3 kPa restricted stomatal conductance of T. discolor to 10-40% of maximum conductance. These results highlight the need to account for changes in VPD when estimating temperature responses of plant species under future <span class="hlt">warming</span> scenarios. Increasing temperature in the future will likely be an important limiting factor to the distribution of T. discolor, especially along the southern edge of its range.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20030015490','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20030015490"><span id="translatedtitle">A Downturn of the Strong <span class="hlt">Winter-Warming</span> Trend In Europe</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Otterman, Joseph; Atlas, Robert; Bungato, Dennis; Koslowsky, Dirk; Wos, Alojzy; Atlas, Robert (Technical Monitor)</p> <p>2002-01-01</p> <p>Surface-air temperatures measured in <span class="hlt">winter</span> at 3 meteorological stations in central Europe rise substantially for most of the second-half of the 20th century. This means shorter <span class="hlt">winter</span>, and longer growing season, which has positive implications for regional agriculture. However, these positive trends stopped in <span class="hlt">winter</span> of 1996, and for the recent 7 years no further climatic amelioration is reported.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017OcSci..13..105X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017OcSci..13..105X"><span id="translatedtitle">Synoptic fluctuation of the Taiwan <span class="hlt">Warm</span> Current in <span class="hlt">winter</span> on the East China Sea shelf</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xuan, Jiliang; Huang, Daji; Pohlmann, Thomas; Su, Jian; Mayer, Bernhard; Ding, Ruibin; Zhou, Feng</p> <p>2017-02-01</p> <p>The seasonal mean and synoptic fluctuation of the wintertime Taiwan <span class="hlt">Warm</span> Current (TWC) were investigated using a well-validated finite volume community ocean model. The spatial distribution and dynamics of the synoptic fluctuation were highlighted. The seasonal mean of the wintertime TWC has two branches: an inshore branch between the 30 and 100 m isobaths and an offshore branch between the 100 and 200 m isobaths. The Coriolis term is much larger than the inertia term and is almost balanced by the pressure gradient term in both branches, indicating geostrophic balance of the mean current. Two areas with significant fluctuations of the TWC were identified during wintertime. One of the areas is located to the north of Taiwan with velocities varying in the cross-shore direction. These significant cross-shore fluctuations are driven by barotropic pressure gradients associated with the intrusion of the Taiwan Strait Current (TSC). When a strong TSC intrudes to the north of Taiwan, the isobaric slope tilts downward from south to north, leading to a cross-shore current from the coastal area to the offshore area. When the TSC intrusion is weak, the cross-shore current to the north of Taiwan is directed from offshore to inshore. The other area of significant fluctuation is located in the inshore area between the 30 and 100 m isobaths. The fluctuations are generally strong both in the alongshore and cross-shore directions, in particular at the latitudes 26.5 and 28° N. Wind affects the synoptic fluctuation through episodic events. When the northeasterly monsoon prevails, the southwestward Zhe-Min coastal current dominates the inshore area associated with a deepening of the mixed layer. When the <span class="hlt">winter</span> monsoon is weakened or the southwesterly wind prevails, the northeastward TWC dominates in the inshore area.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ClDy..tmp...81X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ClDy..tmp...81X"><span id="translatedtitle"><span class="hlt">Extreme</span> subsurface <span class="hlt">warm</span> events in the South China Sea during 1998/99 and 2006/07: observations and mechanisms</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xiao, Fuan; Zeng, Lili; Liu, Qin-Yan; Zhou, Wen; Wang, Dongxiao</p> <p>2017-03-01</p> <p>Conductivity-temperature-depth observations, objectively analyzed data, and model output are used to investigate the variability of subsurface temperature in the South China Sea (SCS) during 1948-2010. Two <span class="hlt">extreme</span> subsurface <span class="hlt">warm</span> events are identified during 1998/99 and 2006/07, with no corresponding <span class="hlt">extreme</span> surface <span class="hlt">warming</span> except in 1998. Mixed-layer heat budget analysis reveals that the lack of significant heat input from surface net heat flux or from current advection is responsible for the absence of <span class="hlt">extreme</span> surface <span class="hlt">warming</span> during 1999, and 2006/07. The surface net heat flux alone cannot explain the first phases of subsurface <span class="hlt">warming</span> during 1998/99 and 2006/07. <span class="hlt">Warm</span> advection from the southern SCS in 1998/99 and from the Kuroshio intrusion in 2006/07, induced by anomalous ocean currents, is likely the major contributor to <span class="hlt">warming</span> of the subsurface water. During the second phase of <span class="hlt">warming</span>, the surface net heat flux plays a damping role to cool the subsurface water, and the <span class="hlt">warm</span> advection induced by anomalous SCS western boundary currents from the southern SCS leads to <span class="hlt">extremely</span> <span class="hlt">warm</span> subsurface water anomalies. The results show the importance of the Pacific western boundary currents, especially the Kuroshio, in maintaining <span class="hlt">extreme</span> subsurface <span class="hlt">warm</span> events in the SCS.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26090931','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26090931"><span id="translatedtitle">Changes in <span class="hlt">Extremely</span> Hot Summers over the Global Land Area under Various <span class="hlt">Warming</span> Targets.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wang, Lei; Huang, Jianbin; Luo, Yong; Yao, Yao; Zhao, Zongci</p> <p>2015-01-01</p> <p>Summer temperature <span class="hlt">extremes</span> over the global land area were investigated by comparing 26 models of the fifth phase of the Coupled Model Intercomparison Project (CMIP5) with observations from the Goddard Institute for Space Studies (GISS) and the Climate Research Unit (CRU). Monthly data of the observations and models were averaged for each season, and statistics were calculated for individual models before averaging them to obtain ensemble means. The summers with temperature anomalies (relative to 1951-1980) exceeding 3σ (σ is based on the local internal variability) are defined as "<span class="hlt">extremely</span> hot". The models well reproduced the statistical characteristics evolution, and partly captured the spatial distributions of historical summer temperature <span class="hlt">extremes</span>. If the global mean temperature increases 2°C relative to the pre-industrial level, "<span class="hlt">extremely</span> hot" summers are projected to occur over nearly 40% of the land area (multi-model ensemble mean projection). Summers that exceed 5σ <span class="hlt">warming</span> are projected to occur over approximately 10% of the global land area, which were rarely observed during the reference period. Scenarios reaching <span class="hlt">warming</span> levels of 3°C to 5°C were also analyzed. After exceeding the 5°C <span class="hlt">warming</span> target, "<span class="hlt">extremely</span> hot" summers are projected to occur throughout the entire global land area, and summers that exceed 5σ <span class="hlt">warming</span> would become common over 70% of the land area. In addition, the areas affected by "<span class="hlt">extremely</span> hot" summers are expected to rapidly expand by more than 25%/°C as the global mean temperature increases by up to 3°C before slowing to less than 16%/°C as the temperature continues to increase by more than 3°C. The area that experiences summers with <span class="hlt">warming</span> of 5σ or more above the <span class="hlt">warming</span> target of 2°C is likely to maintain rapid expansion of greater than 17%/°C. To reduce the impacts and damage from severely hot summers, the global mean temperature increase should remain low.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NatCC...5..132C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NatCC...5..132C"><span id="translatedtitle">Increased frequency of <span class="hlt">extreme</span> La Niña events under greenhouse <span class="hlt">warming</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cai, Wenju; Wang, Guojian; Santoso, Agus; McPhaden, Michael J.; Wu, Lixin; Jin, Fei-Fei; Timmermann, Axel; Collins, Mat; Vecchi, Gabriel; Lengaigne, Matthieu; England, Matthew H.; Dommenget, Dietmar; Takahashi, Ken; Guilyardi, Eric</p> <p>2015-02-01</p> <p>The El Niño/Southern Oscillation is Earth’s most prominent source of interannual climate variability, alternating irregularly between El Niño and La Niña, and resulting in global disruption of weather patterns, ecosystems, fisheries and agriculture. The 1998-1999 <span class="hlt">extreme</span> La Niña event that followed the 1997-1998 <span class="hlt">extreme</span> El Niño event switched <span class="hlt">extreme</span> El Niño-induced severe droughts to devastating floods in western Pacific countries, and vice versa in the southwestern United States. During <span class="hlt">extreme</span> La Niña events, cold sea surface conditions develop in the central Pacific, creating an enhanced temperature gradient from the Maritime continent to the central Pacific. Recent studies have revealed robust changes in El Niño characteristics in response to simulated future greenhouse <span class="hlt">warming</span>, but how La Niña will change remains unclear. Here we present climate modelling evidence, from simulations conducted for the Coupled Model Intercomparison Project phase 5 (ref. ), for a near doubling in the frequency of future <span class="hlt">extreme</span> La Niña events, from one in every 23 years to one in every 13 years. This occurs because projected faster mean <span class="hlt">warming</span> of the Maritime continent than the central Pacific, enhanced upper ocean vertical temperature gradients, and increased frequency of <span class="hlt">extreme</span> El Niño events are conducive to development of the <span class="hlt">extreme</span> La Niña events. Approximately 75% of the increase occurs in years following <span class="hlt">extreme</span> El Niño events, thus projecting more frequent swings between opposite <span class="hlt">extremes</span> from one year to the next.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.7084M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.7084M"><span id="translatedtitle">Arctic sea ice loss and recent <span class="hlt">extreme</span> cold <span class="hlt">winter</span> in Eurasia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mori, Masato; Watanabe, Masahiro; Ishii, Masayoshi; Kimoto, Masahide</p> <p>2014-05-01</p> <p><span class="hlt">Extreme</span> cold <span class="hlt">winter</span> over the Eurasia has occurred more frequently in recent years. Observational evidence in recent studies shows that the wintertime cold anomalies over the Eurasia are associated with decline of Arctic sea ice in preceding autumn to <span class="hlt">winter</span> season. However, the tropical and/or mid-latitude sea surface temperature (SST) anomalies have great influence on the mid- and high-latitude atmospheric variability, it is difficult to isolate completely the impacts of sea ice change from observational data. In this study, we examine possible linkage between the Arctic sea ice loss and the <span class="hlt">extreme</span> cold <span class="hlt">winter</span> over the Eurasia using a state-of-the-art MIROC4 (T106L56) atmospheric general circulation model (AGCM) to assess the pure atmospheric responses to sea ice reduction. We perform two sets of experiments with different realistic sea ice boundary conditions calculated by composite of observed sea ice concentration; one is reduced sea ice extent case (referred to as LICE run) and another is enhanced case (HICE run). In both experiments, the model is integrated 6-month from September to February with 100-member ensemble under the climatological SST boundary condition. The difference in ensemble mean of each experiment (LICE minus HICE) shows cold anomalies over the Eurasia in <span class="hlt">winter</span> and its spatial pattern is very similar to corresponding observation, though the magnitude is smaller than observation. This result indicates that a part of observed cold anomaly can be attributed to the Arctic sea ice loss. We would like to introduce more important results and mechanisms in detail in my presentation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..1713010G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..1713010G"><span id="translatedtitle"><span class="hlt">Winter</span> climate <span class="hlt">extremes</span> and their role for priming SOM decomposition under the snow</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gavazov, Konstantin; Bahn, Michael</p> <p>2015-04-01</p> <p>The central research question of this project is how soil respiration and soil microbial community composition and activity of subalpine grasslands are affected by <span class="hlt">extreme</span> <span class="hlt">winter</span> climate events, such as mid-<span class="hlt">winter</span> snowmelt and subsequent advanced growing season date. In the scope of this talk, focus will be laid on the assumptions that (1) reduced snow cover leads to intensive freeze-thaw cycles in the soil with larger amplitudes of microbial biomass, DOC and soil CO2 production and efflux over the course of <span class="hlt">winter</span>, and shifts peak microbial activity to deeper soil layers with limited and recalcitrant substrate; (2) causes a shift in microbial community composition towards decreased fungal/bacterial ratios; and (3) results in a stronger incorporation of labile C in microbial biomass and more pronounced priming effects of soil organic matter turnover. Our findings indicate that snow removal, induces a strong and immediate negative effect on the physiology of soil microbes, impairing them in their capacity for turnover of SOM in the presence of labile substances (priming). This effect however is transient and soil microbes recover within the same <span class="hlt">winter</span>. The reason for that is that snow removal did not produce any measurable (PLFA) changes in soil microbial community composition. The advanced start of the growing season, as a result of snow removal in mid-<span class="hlt">winter</span>, granted the bacterial part of the microbial community more active in the uptake of labile substrates and the turnover of SOM than the fungal one. This finding is in line with the concept for a seasonal shift towards bacterial-dominated summer microbial community composition and could bring about implications for the plant-microbe competition for resources at the onset of the growing season.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1055191','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1055191"><span id="translatedtitle">Response of snow-dependent hydrologic <span class="hlt">extremes</span> to continued global <span class="hlt">warming</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Diffenbaugh, Noah; Scherer, Martin; Ashfaq, Moetasim</p> <p>2012-01-01</p> <p>Snow accumulation is critical for water availability in the Northern Hemisphere1,2, raising concern that global <span class="hlt">warming</span> could have important impacts on natural and human systems in snow-dependent regions1,3. Although regional hydrologic changes have been observed (for example, refs 1,3 5), the time of emergence of <span class="hlt">extreme</span> changes in snow accumulation and melt remains a key unknown for assessing climate- change impacts3,6,7. We find that the CMIP5 global climate model ensemble exhibits an imminent shift towards low snow years in the Northern Hemisphere, with areas of western North America, northeastern Europe and the Greater Himalaya showing the strongest emergence during the near- termdecadesandat2 Cglobalwarming.Theoccurrenceof <span class="hlt">extremely</span> low snow years becomes widespread by the late twenty-first century, as do the occurrences of <span class="hlt">extremely</span> high early-season snowmelt and runoff (implying increasing flood risk), and <span class="hlt">extremely</span> low late-season snowmelt and runoff (implying increasing water stress). Our results suggest that many snow-dependent regions of the Northern Hemisphere are likely to experience increasing stress from low snow years within the next three decades, and from <span class="hlt">extreme</span> changes in snow-dominated water resources if global <span class="hlt">warming</span> exceeds 2 C above the pre-industrial baseline.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1023285','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1023285"><span id="translatedtitle">Intensity, duration, and frequency of precipitation <span class="hlt">extremes</span> under 21st-century <span class="hlt">warming</span> scenarios</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kao, Shih-Chieh; Ganguly, Auroop R</p> <p>2011-01-01</p> <p>Recent research on the projection of precipitation <span class="hlt">extremes</span> has either focused on conceptual physical mechanisms that generate heavy precipitation or rigorous statistical methods that extrapolate tail behavior. However, informing both climate prediction and impact assessment requires concurrent physically and statistically oriented analysis. A combined examination of climate model simulations and observation-based reanalysis data sets suggests more intense and frequent precipitation <span class="hlt">extremes</span> under 21st-century <span class="hlt">warming</span> scenarios. Utilization of statistical <span class="hlt">extreme</span> value theory and resampling-based uncertainty quantification combined with consideration of the Clausius-Clapeyron relationship reveals consistently intensifying trends for precipitation <span class="hlt">extremes</span> at a global-average scale. However, regional and decadal analyses reveal specific discrepancies in the physical mechanisms governing precipitation <span class="hlt">extremes</span>, as well as their statistical trends, especially in the tropics. The intensifying trend of precipitation <span class="hlt">extremes</span> has quantifiable impacts on intensity-duration-frequency curves, which in turn have direct implications for hydraulic engineering design and water-resources management. The larger uncertainties at regional and decadal scales suggest the need for caution during regional-scale adaptation or preparedness decisions. Future research needs to explore the possibility of uncertainty reduction through higher resolution global climate models, statistical or dynamical downscaling, as well as improved understanding of precipitation <span class="hlt">extremes</span> processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014SPIE.9292E..4GM','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014SPIE.9292E..4GM"><span id="translatedtitle">The study of the special features of <span class="hlt">winter</span> stratospheric <span class="hlt">warming</span> manifestations over Tomsk according to the lidar temperature measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Marichev, V. N.; Samokhvalov, I. V.</p> <p>2014-11-01</p> <p>In the article the lidar observations of the <span class="hlt">winter</span> stratosphere <span class="hlt">warming</span> manifestations of (SW) 2011-13 over Tomsk are considered. In 2010/11 the <span class="hlt">winter</span> <span class="hlt">warming</span> took place in January with insignificant positive temperature deviations from the mean monthly values in its first decade and then two maxima on the 14th and 15th of January at the altitude of 30-40 km with a deviation to 45K. In 2011/12 the beginning of the SW was recorded from lidar measurements on December 26 and lasted for two decades of January. The maximum development of SW was at the end of December 2011 - the first decade of January. The biggest temperature deviations were at the 40-60K level in the height interval of 35-45 km. In 2012/13 the SW began on December 25. The phase of its maximum development fell on the 1-4th of January when the stratopause altitude dropped on 30 km and the maximum temperature deviation from the model at this level reached 70K. In contrast to the first two <span class="hlt">warming</span> (minor), the last was referred to the major type wherein air mass circulation change happened in the upper stratosphere over Tomsk ((http://www.geo.fu-berlin.de/en/met/ag/strat/index.html).).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1811084S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1811084S"><span id="translatedtitle">Impact of radiosonde data over the Arctic ice on forecasting <span class="hlt">winter</span> <span class="hlt">extreme</span> weather over mid latitude</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sato, Kazutoshi; Inoue, Jun; Yamazaki, Akira; Kim, Joo-hong; Maturilli, Marion; Dethloff, Klaus; Hudson, Stephen</p> <p>2016-04-01</p> <p>In February 2015, the Arctic air outbreak caused <span class="hlt">extreme</span> cold events and heavy snowfall over the mid latitude, in particular over the North America. During the <span class="hlt">winter</span>, special radiosonde observations were made on the Norwegian RV Lance around the north of Svalbard under the N-ICE2015 project. We investigated the impact of the radiosonde data on forecasting of a cold <span class="hlt">extreme</span> event over the eastern North America using the AFES-LETKF experimental ensemble reanalysis version2 (ALERA2) data set. ALERA2 was used as the reference reanalysis (CTL) while the observing-system experiment (OSE) assimilated the same observational data set, except for the radiosonde data obtained by the RV Lance. Using these two reanalysis data as initial values, ensemble forecasting experiments were conducted. Comparing these ensemble forecasts, there were large differences in the position and depth of a predicted tropopause polar vortex. The CTL forecast well predicted the southward intrusion of the polar vortex which pushed a cold air over the eastern North America from the Canadian Archipelago. In the OSE forecast, in contrast, the trough associated with southward intrusion of the polar vortex was weak, which prevented a cold outbreak from Arctic. This result suggested that the radiosonde observations over the central Arctic would improve the skill of weather forecasts during <span class="hlt">winter</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMGC54A..03S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMGC54A..03S"><span id="translatedtitle">Changes in Large Spatiotemporal Climatic <span class="hlt">Extreme</span> Events Beyond the Mean <span class="hlt">Warming</span> Signal</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sippel, S.; Mahecha, M. D.; Otto, F. E. L.</p> <p>2014-12-01</p> <p>Weather and climate <span class="hlt">extremes</span> impose substantial impacts on human societies and ecosystems. In particular, events that are large in space (areal extent), time (duration) or both are likely to be associated with highly significant consequences. Hence, a better detection, characterization and understanding of such anomalous events is crucial. There is widespread consensus on a global and continental-scale <span class="hlt">warming</span> trend, which leads to increases in the number, magnitude and frequency of temperature <span class="hlt">extremes</span> (Hansen et al., 2012). It is less clear, however, if this <span class="hlt">warming</span> also coincides with a broadening of temperature distributions (Huntingford et al., 2013). Moreover, the question whether other climate variables, such as large-scale precipitation deficits, likewise change, remains largely unanswered (Sheffield et al., 2012; Seneviratne 2012). In this study, we address this issue by investigating the characteristics of large <span class="hlt">extremes</span>, using an algorithm that detects the n largest spatiotemporally connected climate <span class="hlt">extremes</span> for any time period. The deployed algorithm detects, depending on the chosen time step and variable, major heat waves, cold spells or droughts. We find a robust increase in the magnitude of large hot temperature <span class="hlt">extremes</span> on a global and European scale in observations and reanalysis products, whereas the duration and affected area of those <span class="hlt">extremes</span> does not show any pronounced changes. These results reveal that there is a detectable signal in temperature distributions beyond the mean <span class="hlt">warming</span> trend, which might imply a structural change in the making of large <span class="hlt">extreme</span> events. Furthermore, we use the CMIP5 ensemble of models and an ensemble of 100+ members of a regional climate model for Europe (HadRM3P within the weather@home framework[1]) in order to conduct a global and continental-scale analysis of large <span class="hlt">extreme</span> events in temperature and precipitation. The employment of those model ensembles allows to sample more reliably the tails of the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1815300M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1815300M"><span id="translatedtitle">Attributing <span class="hlt">extreme</span> precipitation in the Black Sea region to sea surface <span class="hlt">warming</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Meredith, Edmund; Semenov, Vladimir; Maraun, Douglas; Park, Wonsun; Chernokulsky, Alexander</p> <p>2016-04-01</p> <p>Higher sea surface temperatures (SSTs) <span class="hlt">warm</span> and moisten the overlying atmosphere, increasing the low-level atmospheric instability, the moisture available to precipitating systems and, hence, the potential for intense convective systems. Both the Mediterranean and Black Sea regions have seen a steady increase in summertime SSTs since the early 1980s, by over 2 K in places. This raises the question of how this SST increase has affected convective precipitation <span class="hlt">extremes</span> in the region, and through which mechanisms any effects are manifested. In particular, the Black Sea town of Krymsk suffered an unprecedented precipitation <span class="hlt">extreme</span> in July 2012, which may have been influenced by Black Sea <span class="hlt">warming</span>, causing over 170 deaths. To address this question, we adopt two distinct modelling approaches to event attribution and compare their relative merits. In the first, we use the traditional probabilistic event attribution approach involving global climate model ensembles representative of the present and a counterfactual past climate where regional SSTs have not increased. In the second, we use the conditional event attribution approach, taking the 2012 Krymsk precipitation <span class="hlt">extreme</span> as a showcase example. Under the second approach, we carry out ensemble sensitivity experiments of the Krymsk event at convection-permitting resolution with the WRF regional model, and test the sensitivity of the event to a range of SST forcings. Both experiments show the crucial role of recent Black Sea <span class="hlt">warming</span> in amplifying the 2012 Krymsk precipitation <span class="hlt">extreme</span>. In the conditional event attribution approach, though, the explicit simulation of convective processes provides detailed insight into the physical mechanisms behind the <span class="hlt">extremeness</span> of the event, revealing the dominant role of dynamical (i.e. static stability and vertical motions) over thermodynamical (i.e. increased atmospheric moisture) changes. Additionally, the wide range of SST states tested in the regional setup, which would be</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.A13A0291L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.A13A0291L"><span id="translatedtitle">The dynamical signature on the change of hydrological <span class="hlt">extremes</span> under global <span class="hlt">warming</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lu, J.; Gao, Y.; Leung, L. R.; Chen, G.; Yang, Q.</p> <p>2015-12-01</p> <p>The increased water vapor content due to climate <span class="hlt">warming</span> can impact the global hydrological cycle not only by the direct thermodynamic effect constrained by the Clausius-Clapeyron relation, but also impinging on features of circulation through coupling with the atmospheric dynamics. Through implementing the concept of finite-amplitude wave activity (FAWA) and its three-dimensional extension to local FAWA, the increase of the hydrological <span class="hlt">extremes</span> manifested in terms of FAWA under climate change scenario RCP8.5 can be decomposed into the part due to the background increase of moisture (scaled with the temperature <span class="hlt">warming</span>, thus representing thermodynamical effect) and the part due to the change of waviness of the contours of moisture (representing the dynamical factor). It is found that the both thermodynamical increase of moisture and the change of the waviness project on to the enhancement of the climatological pattern of the FAWA associated with the poleward moisture intrusion (Am). Whereas, the change of the FAWA associated with the dry air intrusion (Ad) is characterized by both an enhancement of the background pattern and a poleward expansion thereof, the latter arising from the poleward shift of the wavy motion. This result may serve as a rationale for why both dry and wet <span class="hlt">extremes</span> will become more frequent while the time mean temperature and water vapor increase under global <span class="hlt">warming</span>. The relative contributions to the response of the waviness in the moisture distribution from the stationary wave versus the transient waves will also be examined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMOS23C1236G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMOS23C1236G"><span id="translatedtitle">Impact of the <span class="hlt">Extreme</span> <span class="hlt">Warming</span> of 2012 on Shelfbreak Frontal Structure North of Cape Hatteras</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gawarkiewickz, G.</p> <p>2014-12-01</p> <p>Continental shelf circulation north of Cape Hatteras is complex, with southward flowing Middle Atlantic Bight shelf water intersecting the Gulf Stream and subducting offshore into the Gulf Stream. In May, 2012, a cruise was conducted in order to study the shelf circulation and acoustic propagation through fish schools in the area. An important aspect of the study was to use Autonomous Underwater Vehicles to map fish schools with a sidescan sonar. High-resolution hydrographic surveys to map the continental shelf water masses and shelfbreak frontal structure were sampled to relate oceanographic conditions to the fish school distributions. The cold pool water mass over the continental shelf in May 2012 was <span class="hlt">extremely</span> <span class="hlt">warm</span>, with temperature anomalies of up to 5 Degrees C relative to observations from the same area in May, 1996. The normal cross-shelf temperature gradients within the shelfbreak front were not present because of the <span class="hlt">warming</span>. As a result, the shelf density field was much more buoyant than usual, which led to an accelerated shelfbreak jet. Moored velocity measurements at the 60 m isobath recorded alongshelf flow of as much as 0.6 m/s. The anticipated fish species were not observed over the continental shelf. Some comments on the forcing leading to the large scale <span class="hlt">warming</span> will be presented, along with a brief discussion of the impact of the <span class="hlt">warming</span> on the marine ecosystem in the northeast U.S.</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/2015PhDT.......146B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhDT.......146B"><span id="translatedtitle"><span class="hlt">Warm</span>-season diurnal circulations and heat <span class="hlt">extremes</span> over the northwest U.S</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brewer, Matthew C.</p> <p></p> <p>Summer synoptic circulations over the northwest U.S., and their interactions with regional terrain, land/water contrasts, and surface heating, give rise to a variety of fascinating meteorological phenomena, many of which have yet to be explored. Furthermore, it is largely unknown how projected future <span class="hlt">warming</span> associated with increased greenhouse gases will modify these important features. The work herein seeks to ameliorate this with a comprehensive examination of two important aspects of northwest U.S. summer weather and climate: diurnal circulations and changes to the conditions associated with <span class="hlt">extreme</span> temperatures under anthropogenic global <span class="hlt">warming</span>. To simulate regional diurnal circulations, GFS model output was obtained for July and August 2009-2011. These data were categorized into hour of the day, composited, and the resulting files were used to initialize and provide boundary conditions to a WRF (version 3.5) model run. It was shown that, when compared to observations, this WRF run sufficiently simulates average diurnal variability. Using this simulation, the diurnal circulations of the region were described, including several important wind features within the Strait of Juan de Fuca, the Snoqualmie Pass, and the Columbia River Gorge. Also, regional nocturnal low-level wind maxima are described, including one over the northern Willamette valley and another over the high plateau of eastern Oregon. Recent work by the authors has elucidated the physical mechanisms that drive heat <span class="hlt">extremes</span> over the northwest U.S., including the necessity of a ridge aloft, with associated subsidence and advection <span class="hlt">warming</span>. Also, easterly flow is crucial for keeping the marine air at bay, and producing downslope flow and adiabatic <span class="hlt">warming</span> on the western slopes of regional north-south terrain barriers. Given the rising temperatures projected under anthropogenic global <span class="hlt">warming</span>, how are these conditions, and associated low-level temperature distributions, projected to change? As a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.A54B..07L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.A54B..07L"><span id="translatedtitle">Increasing contrasts between wet and dry precipitation <span class="hlt">extremes</span> during the "global <span class="hlt">warming</span> hiatus" (1998-2013)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lau, W. K. M.; Wu, H. T.</p> <p>2015-12-01</p> <p>We investigate changes in daily precipitation <span class="hlt">extremes</span> using TRMM data (1998-2013), which coincides with the so-called "global <span class="hlt">warming</span> hiatus". Results show a structural change in probability distribution functions (pdf) of local precipitation events (LPE) during this period, indicating more intense LPE, less moderate LPE, and more dry (no-rain) days globally. Analyses for land and ocean separately reveal more complex and nuanced changes over land, characterized by a strong positive trend (+12.0% per decade, 99% confidence level (c.l.)) in frequency of <span class="hlt">extreme</span> LPE's over the Northern Hemisphere extratropics during the wet season, but a negative global trend (-6.6% per decade, 95% c.l.) during the dry season. Analyses of the risk of drought based on the number of dry days show a significant global drying trend (3.2% per decade, 99% c.l.) over land during the dry season. Regions of pronounced increased drought include western and central US, northeastern Asia and southern Europe/Mediterranean. Trends in cloud distributions from TRMM VIS-IR, and relative humidity from reanalysis have also been examined. Overall, the changes in water cycle parameters are consistent with increasing contrasts between wet and dry precipitation <span class="hlt">extremes</span>, as reported in previous studies based on observations and climate model projections for a longer period, implying changes in global water cycle was underway during 1998-2013 as if there is no "global <span class="hlt">warming</span> hiatus". The implications of the present results will be discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMGC11A0976C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMGC11A0976C"><span id="translatedtitle">North America <span class="hlt">Extreme</span> Precipitation Changes under Global <span class="hlt">Warming</span>: ATHENA model results and Observations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chiu, L.; Lu, J.; Huang, B.; Feng, X.</p> <p>2013-12-01</p> <p>Global climate models have generally shown a more <span class="hlt">extreme</span> climate under global <span class="hlt">warming</span> scenarios. A quantitative assessment of precipitation <span class="hlt">extreme</span> is crucial in light of the damage produced by recent Hurricane Sandy and for water resource management in general. We examined the spatial and temporal structure of <span class="hlt">extreme</span> precipitation from climate models and compare them with observed datasets derived from satellite and rain gauge analyses. Results from the ATHENA project (for high resolution global climate simulations) at resolutions of T159 and T1279, corresponding to resolutions of about 128km and 16km, respectively, with 6 hourly output are analyzed. The high resolution T1279 data revealed fine scale dependence on topography, such as the mountain ranges in the west coast, which are not resolved in T159. The high resolution data also show higher and more variable annual maximum. Comparison of AMIP and Time Slice data also reveal that the return periods of heavy rainfall decrease, or more frequent recurrence of <span class="hlt">extreme</span> events under a global <span class="hlt">warming</span> scenario. A Generalized <span class="hlt">Extremely</span> Value (GEV) distribution is used to examine the parametric dependence of annual maximum rainfall although other EV distributions, such as a Frechet (EV type II) or Gumble (EV type I) distribution often perform better than the GEV. The estimated shape parameter, which determines the skewness of the distribution, is generally small and in the range of less than 0.2. Assuming the shape parameter is zero, the GEV reduces to a two parameter distribution- the location and scale parameters. Annual maximum rainfall derived from the Global Precipitation Climatology Project (GPCP) one degree daily (1dd) product and the TRMM Merged Precipitation Analysis (TMPA) at 0.25 degree and 3 hourly resolutions are compiled and analyzed. Comparison between the ATHENA and satellite-gauge products shows that their spatial pattern is quite similar while the models tend to underestimate annual maximum rainfall</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..14.3860L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..14.3860L"><span id="translatedtitle">Climate <span class="hlt">Extremes</span> Triggered State Shifting of US Great Plains Prairie under Experimental <span class="hlt">Warming</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Luo, Y.; Xu, X.; Sherry, R.; Niu, S.; Li, D.; Xia, J.</p> <p>2012-04-01</p> <p>Ecosystems can exist under multiple stable states. Transition from one stable state to another is usually triggered by perturbations such as climate <span class="hlt">extremes</span>, which should be large enough to push the ecosystem over a threshold. Ecosystem state changes can alter ecosystem functions and services as dramatically as in Sahara with vegetation changes from tropical forests to grassland and deserts over 6000 years. Thus it is crucial to understand mechanisms underlying ecosystem state changes. State changes of ecosystem vegetation have been well documented in paleo-records and predicted to occur under climate change by dynamic global vegetation models. Paleo-records usually offer broad-scale patterns of ecosystem state changes over time and rarely offer much insight into fundamental mechanisms underlying the state changes. Model predictions may be calibrated against contemporary and paleo vegetation distributions but have not been carefully tested against experimental evidence. The latter, however, is <span class="hlt">extremely</span> rare largely because global chance experiments are mostly short term. We have observed state shifting of a US Great Plains prairie under long-term experimental <span class="hlt">warming</span> and clipping treatments. Our analysis of 11-year data from the experiment showed two-stage stimulations of aboveground net primary production (ANPP) with small increases in the first 7 followed by distinctly large increases under experimental <span class="hlt">warming</span> in comparison with those under control. The two-stage ANPP simulations were corresponded with species reordering with the plant community over time but not related to <span class="hlt">warming</span>-induced changes in temperature, soil moisture and nitrogen dynamics in the grassland. The state shifting of the grassland under the experimental <span class="hlt">warming</span> was partly because our experimental site locates in an ecotone between the mixed and tall grass prairies. Under the experimental <span class="hlt">warming</span>, the prairie was shifting from the mixed prairie as dominated by Schizachyrium scoparium</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..1711162M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..1711162M"><span id="translatedtitle">Role of Sea Surface <span class="hlt">Warming</span> in Triggering Amplification of Coastal Rainfall <span class="hlt">Extremes</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Meredith, Edmund; Semenov, Vladimir; Maraun, Douglas; Park, Wonsun; Chernokulsky, Alexander</p> <p>2015-04-01</p> <p>Whether recent changes in the occurrence of meteorological <span class="hlt">extremes</span> are attributable to a warmer climate remains a challenging question. One area where the potential for <span class="hlt">extreme</span> summertime convective precipitation has grown recently, along with substantial sea surface temperature (SST) increase, is the Black Sea and Mediterranean (BSM) region. To study mechanisms through which SST increase may impact BSM convective <span class="hlt">extremes</span>, we take the July 2012 precipitation <span class="hlt">extreme</span> near the Black Sea town of Krymsk as a recent showcase example. The event was related to a slow moving low pressure system crossing the eastern Black Sea, advecting <span class="hlt">warm</span> and moist air towards the coast. Two waves of convection resulted in precipitation totals that dwarfed all previous events in the instrumental record, dating back to the 1930s, and over 170 deaths. The synoptic environment which led to this event is typical of that found with intense summertime precipitation in the BSM region. We carry out ensemble sensitivity experiments over an eastern Black Sea domain with the WRF regional model, using multiply nested sub-domains, increasing to 600 m convection resolving resolution. The model's ability to reproduce the event with observed SST forcing is first verified, before a series of additional ensembles with altered SST is created. These ensembles consist of subtracting (adding) the 1982 - 2012 trend in Black Sea SST from (to) the observed 2012 SST field in 20% increments, giving a total of 11 ensembles whose SST differ from the observed field by between -100% and +100% of the <span class="hlt">warming</span> trend. We demonstrate that such an intense precipitation event would not have been possible without the recent Black Sea <span class="hlt">warming</span>. The increased SST enhances low-level instability, allowing deep convection to be triggered and causing a more than 300% increase in precipitation. Additionally, a highly nonlinear precipitation response to incrementally increasing SST suggests that Black Sea SSTs have exceeded a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24523499','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24523499"><span id="translatedtitle">Differential impacts of ocean acidification and <span class="hlt">warming</span> on <span class="hlt">winter</span> and summer progeny of a coastal squid (Loligo vulgaris).</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Rosa, Rui; Trübenbach, Katja; Pimentel, Marta S; Boavida-Portugal, Joana; Faleiro, Filipa; Baptista, Miguel; Dionísio, Gisela; Calado, Ricardo; Pörtner, Hans O; Repolho, Tiago</p> <p>2014-02-15</p> <p>Little is known about the capacity of early life stages to undergo hypercapnic and thermal acclimation under the future scenarios of ocean acidification and <span class="hlt">warming</span>. Here, we investigated a comprehensive set of biological responses to these climate change-related variables (2°C above <span class="hlt">winter</span> and summer average spawning temperatures and ΔpH=0.5 units) during the early ontogeny of the squid Loligo vulgaris. Embryo survival rates ranged from 92% to 96% under present-day temperature (13-17°C) and pH (8.0) scenarios. Yet, ocean acidification (pH 7.5) and summer <span class="hlt">warming</span> (19°C) led to a significant drop in the survival rates of summer embryos (47%, P<0.05). The embryonic period was shortened by increasing temperature in both pH treatments (P<0.05). Embryo growth rates increased significantly with temperature under present-day scenarios, but there was a significant trend reversal under future summer <span class="hlt">warming</span> conditions (P<0.05). Besides pronounced premature hatching, a higher percentage of abnormalities was found in summer embryos exposed to future <span class="hlt">warming</span> and lower pH (P<0.05). Under the hypercapnic scenario, oxygen consumption rates decreased significantly in late embryos and newly hatched paralarvae, especially in the summer period (P<0.05). Concomitantly, there was a significant enhancement of the heat shock response (HSP70/HSC70) with <span class="hlt">warming</span> in both pH treatments and developmental stages. Upper thermal tolerance limits were positively influenced by acclimation temperature, and such thresholds were significantly higher in late embryos than in hatchlings under present-day conditions (P<0.05). In contrast, the upper thermal tolerance limits under hypercapnia were higher in hatchlings than in embryos. Thus, we show that the stressful abiotic conditions inside the embryo's capsules will be exacerbated under near-future ocean acidification and summer <span class="hlt">warming</span> scenarios. The occurrence of prolonged embryogenesis along with lowered thermal tolerance limits under such</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1038586','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1038586"><span id="translatedtitle">Changes in <span class="hlt">winter</span> precipitation <span class="hlt">extremes</span> for the western United States under a warmer climate as simulated by regional climate models</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Dominguez, F; Rivera, E; Lettenmaier, D P; Castro1, and C. L.</p> <p>2012-03-01</p> <p>We find a consistent and statistically significant increase in the intensity of future <span class="hlt">extreme</span> <span class="hlt">winter</span> precipitation events over the western United States, as simulated by an ensemble of regional climatemodels (RCMs) driven by IPCC AR4 global climate models (GCMs). All eight simulations analyzed in this work consistently show an increase in the intensity of <span class="hlt">extreme</span> <span class="hlt">winter</span> precipitation with the multi-model mean projecting an area-averaged 12.6% increase in 20-year return period and 14.4% increase in 50-year return period daily precipitation. In contrast with <span class="hlt">extreme</span> precipitation, the multi-model ensemble shows a decrease in mean <span class="hlt">winter</span> precipitation of approximately 7.5% in the southwestern US, while the interior west shows less statistically robust increases.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PalOc..31.1206A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PalOc..31.1206A"><span id="translatedtitle">The "<span class="hlt">warm</span>" Marine Isotope Stage 31 in the Labrador Sea: Low surface salinities and cold subsurface waters prevented <span class="hlt">winter</span> convection</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Aubry, A. M. R.; Vernal, A.; Hillaire-Marcel, C.</p> <p>2016-09-01</p> <p>Surface and subsurface conditions in the Labrador Sea during Marine Isotope Stage (MIS) 31 at the Integrated Ocean Drilling Program Site U1305 off southwest Greenland are reconstructed based on dinocyst and foraminifer assemblages. Isotopic compositions of planktonic (Neogloboquadrina pachyderma, Np) and benthic (Cibicides wuellerstorfi, Cw, and Oridorsalis umbonatus, Ou) foraminifera provide further information about water properties in the mesopelagic layer as well as at the seafloor. Dinocyst proxy reconstructions indicate low salinities (32-34.5), cool <span class="hlt">winters</span> (3-6°C), and mild summers (10-15°C) in the surface water layer during the MIS 31 "optimum". However, planktonic foraminifer assemblages largely dominated by Np suggest relatively cold subsurface conditions in <span class="hlt">winter</span> and summer (<4°C). Lower δ13C values in Np versus Cw further suggest either a lesser-ventilated mesopelagic layer than the bottom one or high organic matter oxidation rates at Np habitat depth. The dinocyst and planktonic foraminifer records together suggest a strong stratification between the surface and subsurface water layers. Isotopic and micropaleontological data thus converge toward paleoceanographical conditions unsuitable for convection and intermediate or deep water formation in the Labrador Sea during the <span class="hlt">warm</span> MIS 31 interglacial, a situation comparable to the one that prevailed during the <span class="hlt">warm</span> MIS 5e.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24919920','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24919920"><span id="translatedtitle">Increased frequency of <span class="hlt">extreme</span> Indian Ocean Dipole events due to greenhouse <span class="hlt">warming</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cai, Wenju; Santoso, Agus; Wang, Guojian; Weller, Evan; Wu, Lixin; Ashok, Karumuri; Masumoto, Yukio; Yamagata, Toshio</p> <p>2014-06-12</p> <p>The Indian Ocean dipole is a prominent mode of coupled ocean-atmosphere variability, affecting the lives of millions of people in Indian Ocean rim countries. In its positive phase, sea surface temperatures are lower than normal off the Sumatra-Java coast, but higher in the western tropical Indian Ocean. During the <span class="hlt">extreme</span> positive-IOD (pIOD) events of 1961, 1994 and 1997, the eastern cooling strengthened and extended westward along the equatorial Indian Ocean through strong reversal of both the mean westerly winds and the associated eastward-flowing upper ocean currents. This created anomalously dry conditions from the eastern to the central Indian Ocean along the Equator and atmospheric convergence farther west, leading to catastrophic floods in eastern tropical African countries but devastating droughts in eastern Indian Ocean rim countries. Despite these serious consequences, the response of pIOD events to greenhouse <span class="hlt">warming</span> is unknown. Here, using an ensemble of climate models forced by a scenario of high greenhouse gas emissions (Representative Concentration Pathway 8.5), we project that the frequency of <span class="hlt">extreme</span> pIOD events will increase by almost a factor of three, from one event every 17.3 years over the twentieth century to one event every 6.3 years over the twenty-first century. We find that a mean state change--with weakening of both equatorial westerly winds and eastward oceanic currents in association with a faster <span class="hlt">warming</span> in the western than the eastern equatorial Indian Ocean--facilitates more frequent occurrences of wind and oceanic current reversal. This leads to more frequent <span class="hlt">extreme</span> pIOD events, suggesting an increasing frequency of <span class="hlt">extreme</span> climate and weather events in regions affected by the pIOD.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JGRC..120.4324C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JGRC..120.4324C"><span id="translatedtitle">The role of atmospheric forcing versus ocean advection during the <span class="hlt">extreme</span> <span class="hlt">warming</span> of the Northeast U.S. continental shelf in 2012</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Ke; Gawarkiewicz, Glen; Kwon, Young-Oh; Zhang, Weifeng G.</p> <p>2015-06-01</p> <p>In the coastal ocean off the Northeast U.S., the sea surface temperature (SST) in the first half of 2012 was the highest on the record for the past roughly 150 years of recorded observations. The underlying dynamical processes responsible for this <span class="hlt">extreme</span> event are examined using a numerical model, and the relative contributions of air-sea heat flux versus lateral ocean advective heat flux are quantified. The model accurately reproduces the observed vertical structure and the spatiotemporal characteristics of the thermohaline condition of the Gulf of Maine and the Middle Atlantic Bight waters during the anomalous <span class="hlt">warming</span> period. Analysis of the model results show that the <span class="hlt">warming</span> event was primarily driven by the anomalous air-sea heat flux, while the smaller contribution by the ocean advection worked against this flux by acting to cool the shelf. The anomalous air-sea heat flux exhibited a shelf-wide coherence, consistent with the shelf-wide <span class="hlt">warming</span> pattern, while the ocean advective heat flux was dominated by localized, relatively smaller-scale processes. The anomalous cooling due to advection primarily resulted from the along-shelf heat flux divergence in the Gulf of Maine, while in the Middle Atlantic Bight the advective contribution from the along-shelf and cross-shelf heat flux divergences was comparable. The modeling results confirm the conclusion of the recent analysis of in situ data by Chen et al. (2014a) that the changes in the large-scale atmospheric circulation in the <span class="hlt">winter</span> of 2011-2012 primarily caused the <span class="hlt">extreme</span> <span class="hlt">warm</span> anomaly in the spring of 2012. The effect of along-shelf or cross-shelf ocean advection on the <span class="hlt">warm</span> anomalies from either the Scotian Shelf or adjacent continental slope was secondary.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25895594','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25895594"><span id="translatedtitle">Areas of potential suitability and survival of Dendroctonus valens in China under <span class="hlt">extreme</span> climate <span class="hlt">warming</span> scenario.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>He, S Y; Ge, X Z; Wang, T; Wen, J B; Zong, S X</p> <p>2015-08-01</p> <p>The areas in China with climates suitable for the potential distribution of the pest species red turpentine beetle (RTB) Dendroctonus valens LeConte (Coleoptera: Scolytidae) were predicted by CLIMEX based on historical climate data and future climate data with <span class="hlt">warming</span> estimated. The model used a historical climate data set (1971-2000) and a simulated climate data set (2010-2039) provided by the Tyndall Centre for Climate Change (TYN SC 2.0). Based on the historical climate data, a wide area was available in China with a suitable climate for the beetle in which every province might contain suitable habitats for this pest, particularly all of the southern provinces. The northern limit of the distribution of the beetle was predicted to reach Yakeshi and Elunchun in Inner Mongolia, and the western boundary would reach to Keerkezi in Xinjiang Province. Based on a global-<span class="hlt">warming</span> scenario, the area with a potential climate suited to RTB in the next 30 years (2010-2039) may extend further to the northeast. The northern limit of the distribution could reach most parts of south Heilongjiang Province, whereas the western limit would remain unchanged. Combined with the tendency for RTB to spread, the variation in suitable habitats within the scenario of <span class="hlt">extreme</span> climate <span class="hlt">warming</span> and the multiple geographical elements of China led us to assume that, within the next 30 years, RTB would spread towards the northeast, northwest, and central regions of China and could be a potentially serious problem for the forests of China.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22481362','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22481362"><span id="translatedtitle">Past <span class="hlt">extreme</span> <span class="hlt">warming</span> events linked to massive carbon release from thawing permafrost.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>DeConto, Robert M; Galeotti, Simone; Pagani, Mark; Tracy, David; Schaefer, Kevin; Zhang, Tingjun; Pollard, David; Beerling, David J</p> <p>2012-04-04</p> <p>Between about 55.5 and 52 million years ago, Earth experienced a series of sudden and <span class="hlt">extreme</span> global <span class="hlt">warming</span> events (hyperthermals) superimposed on a long-term <span class="hlt">warming</span> trend. The first and largest of these events, the Palaeocene-Eocene Thermal Maximum (PETM), is characterized by a massive input of carbon, ocean acidification and an increase in global temperature of about 5 °C within a few thousand years. Although various explanations for the PETM have been proposed, a satisfactory model that accounts for the source, magnitude and timing of carbon release at the PETM and successive hyperthermals remains elusive. Here we use a new astronomically calibrated cyclostratigraphic record from central Italy to show that the Early Eocene hyperthermals occurred during orbits with a combination of high eccentricity and high obliquity. Corresponding climate-ecosystem-soil simulations accounting for rising concentrations of background greenhouse gases and orbital forcing show that the magnitude and timing of the PETM and subsequent hyperthermals can be explained by the orbitally triggered decomposition of soil organic carbon in circum-Arctic and Antarctic terrestrial permafrost. This massive carbon reservoir had the potential to repeatedly release thousands of petagrams (10(15) grams) of carbon to the atmosphere-ocean system, once a long-term <span class="hlt">warming</span> threshold had been reached just before the PETM. Replenishment of permafrost soil carbon stocks following peak <span class="hlt">warming</span> probably contributed to the rapid recovery from each event, while providing a sensitive carbon reservoir for the next hyperthermal. As background temperatures continued to rise following the PETM, the areal extent of permafrost steadily declined, resulting in an incrementally smaller available carbon pool and smaller hyperthermals at each successive orbital forcing maximum. A mechanism linking Earth's orbital properties with release of soil carbon from permafrost provides a unifying model accounting for the salient</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25788025','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25788025"><span id="translatedtitle"><span class="hlt">Winter</span> <span class="hlt">warming</span> as an important co-driver for Betula nana growth in western Greenland during the past century.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hollesen, Jørgen; Buchwal, Agata; Rachlewicz, Grzegorz; Hansen, Birger U; Hansen, Marc O; Stecher, Ole; Elberling, Bo</p> <p>2015-06-01</p> <p>Growing season conditions are widely recognized as the main driver for tundra shrub radial growth, but the effects of <span class="hlt">winter</span> <span class="hlt">warming</span> and snow remain an open question. Here, we present a more than 100 years long Betula nana ring-width chronology from Disko Island in western Greenland that demonstrates a highly significant and positive growth response to both summer and <span class="hlt">winter</span> air temperatures during the past century. The importance of <span class="hlt">winter</span> temperatures for Betula nana growth is especially pronounced during the periods from 1910-1930 to 1990-2011 that were dominated by significant <span class="hlt">winter</span> <span class="hlt">warming</span>. To explain the strong <span class="hlt">winter</span> importance on growth, we assessed the importance of different environmental factors using site-specific measurements from 1991 to 2011 of soil temperatures, sea ice coverage, precipitation and snow depths. The results show a strong positive growth response to the amount of thawing and growing degree-days as well as to <span class="hlt">winter</span> and spring soil temperatures. In addition to these direct effects, a strong negative growth response to sea ice extent was identified, indicating a possible link between local sea ice conditions, local climate variations and Betula nana growth rates. Data also reveal a clear shift within the last 20 years from a period with thick snow depths (1991-1996) and a positive effect on Betula nana radial growth, to a period (1997-2011) with generally very shallow snow depths and no significant growth response towards snow. During this period, <span class="hlt">winter</span> and spring soil temperatures have increased significantly suggesting that the most recent increase in Betula nana radial growth is primarily triggered by warmer <span class="hlt">winter</span> and spring air temperatures causing earlier snowmelt that allows the soils to drain and <span class="hlt">warm</span> quicker. The presented results may help to explain the recently observed 'greening of the Arctic' which may further accelerate in future years due to both direct and indirect effects of <span class="hlt">winter</span> <span class="hlt">warming</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ClDy...48.1213C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ClDy...48.1213C"><span id="translatedtitle">The influence of tropical forcing on <span class="hlt">extreme</span> <span class="hlt">winter</span> precipitation in the western Himalaya</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cannon, Forest; Carvalho, Leila M. V.; Jones, Charles; Hoell, Andrew; Norris, Jesse; Kiladis, George N.; Tahir, Adnan A.</p> <p>2017-02-01</p> <p>Within the Karakoram and western Himalaya (KH), snowfall from <span class="hlt">winter</span> westerly disturbances (WD) maintains the region's snowpack and glaciers, which melt seasonally to sustain water resources for downstream populations. WD activity and subsequent precipitation are influenced by global atmospheric variability and tropical-extratropical interactions. On interannual time-scales, El Niño related changes in tropical diabatic heating induce a Rossby wave response over southwest Asia that is linked with enhanced dynamical forcing of WD and available moisture. Consequently, <span class="hlt">extreme</span> orographic precipitation events are more frequent during El Niño than La Niña or neutral conditions. A similar spatial pattern of tropical diabatic heating is produced by the MJO at intraseasonal scales. In comparison to El Niño, the Rossby wave response to MJO activity is less spatially uniform over southwest Asia and varies on shorter time-scales. This study finds that the MJO's relationship with WD and KH precipitation is more complex than that of ENSO. Phases of the MJO propagation cycle that favor the dynamical enhancement of WD simultaneously suppress available moisture over southwest Asia, and vice versa. As a result, <span class="hlt">extreme</span> precipitation events in the KH occur with similar frequency in most phases of the MJO, however, there is a transition in the relative importance of dynamical forcing and moisture in WD to orographic precipitation in the KH as the MJO evolves. These findings give insight into the dynamics and predictability of <span class="hlt">extreme</span> precipitation events in the KH through their relationship with global atmospheric variability, and are an important consideration in evaluating Asia's water resources.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22895343','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22895343"><span id="translatedtitle">More <span class="hlt">extreme</span> swings of the South Pacific convergence zone due to greenhouse <span class="hlt">warming</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cai, Wenju; Lengaigne, Matthieu; Borlace, Simon; Collins, Matthew; Cowan, Tim; McPhaden, Michael J; Timmermann, Axel; Power, Scott; Brown, Josephine; Menkes, Christophe; Ngari, Arona; Vincent, Emmanuel M; Widlansky, Matthew J</p> <p>2012-08-16</p> <p>The South Pacific convergence zone (SPCZ) is the Southern Hemisphere's most expansive and persistent rain band, extending from the equatorial western Pacific Ocean southeastward towards French Polynesia. Owing to its strong rainfall gradient, a small displacement in the position of the SPCZ causes drastic changes to hydroclimatic conditions and the frequency of <span class="hlt">extreme</span> weather events--such as droughts, floods and tropical cyclones--experienced by vulnerable island countries in the region. The SPCZ position varies from its climatological mean location with the El Niño/Southern Oscillation (ENSO), moving a few degrees northward during moderate El Niño events and southward during La Niña events. During strong El Niño events, however, the SPCZ undergoes an <span class="hlt">extreme</span> swing--by up to ten degrees of latitude toward the Equator--and collapses to a more zonally oriented structure with commensurately severe weather impacts. Understanding changes in the characteristics of the SPCZ in a changing climate is therefore of broad scientific and socioeconomic interest. Here we present climate modelling evidence for a near doubling in the occurrences of zonal SPCZ events between the periods 1891-1990 and 1991-2090 in response to greenhouse <span class="hlt">warming</span>, even in the absence of a consensus on how ENSO will change. We estimate the increase in zonal SPCZ events from an aggregation of the climate models in the Coupled Model Intercomparison Project phases 3 and 5 (CMIP3 and CMIP5) multi-model database that are able to simulate such events. The change is caused by a projected enhanced equatorial <span class="hlt">warming</span> in the Pacific and may lead to more frequent occurrences of <span class="hlt">extreme</span> events across the Pacific island nations most affected by zonal SPCZ events.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.springerlink.com/content/31031027mg27q211/abstract/','USGSPUBS'); return false;" href="http://www.springerlink.com/content/31031027mg27q211/abstract/"><span id="translatedtitle">Temperature inverted haloclines provide <span class="hlt">winter</span> <span class="hlt">warm</span>-water refugia for manatees in southwest Florida</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Stith, Bradley M.; Reid, James P.; Langtimm, Catherine A.; Swain, Eric D.; Doyle, Terry J.; Slone, Daniel H.; Decker, Jeremy D.; Soderqvist, Lars E.</p> <p>2010-01-01</p> <p>Florida manatees (Trichechus manatus latirostris) overwintering in the Ten Thousand Islands and western Everglades have no access to power plants or major artesian springs that provide <span class="hlt">warm</span>-water refugia in other parts of Florida. Instead, hundreds of manatees aggregate at artificial canals, basins, and natural deep water sites that act as passive thermal refugia (PTR). Monitoring at two canal sites revealed temperature inverted haloclines, which provided <span class="hlt">warm</span> salty bottom layers that generally remained above temperatures considered adverse for manatees. At the largest PTR, the warmer bottom layer disappeared unless significant salt stratification was maintained by upstream freshwater inflow over a persistent tidal wedge. A detailed three-dimensional hydrology model showed that salinity stratification inhibited vertical convection induced by atmospheric cooling. Management or creation of temperature inverted haloclines may be a feasible and desirable option for resource managers to provide passive thermal refugia for manatees and other temperature sensitive aquatic species.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMGC43A1158S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMGC43A1158S"><span id="translatedtitle">Global-<span class="hlt">warming</span>-induced Increases in <span class="hlt">Extreme</span> Precipitation are Smallest over Mountains</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shi, X.; Durran, D. R.</p> <p>2015-12-01</p> <p>Climate-model simulations predict an intensification of <span class="hlt">extreme</span> precipitation in almost all areas of the world under global <span class="hlt">warming</span>. Geographical variations in the magnitude of this intensification are clearly evident in the simulations, but most previous efforts to understand the factors responsible for the changes in <span class="hlt">extreme</span> precipitation have focused on zonal averages, neglecting the variations that occur in different regions at the same latitude. Here we present climate-model simulations for an ocean-covered earth having simple idealized continents with north-south mountain barriers in its northern midlatitudes. We show that the sensitivity of <span class="hlt">extreme</span> precipitation to increases in the global mean surface temperature is 3 %/K lower over the mountains than over the oceans and the plains. Fundamental factors responsible for changes in precipitation intensity may be divided between thermodynamic effects, arising through changes in temperature and moisture, and dynamical effects, produced by changes in the ascent rates of saturated air parcels. The difference in sensitivity among these regions is not due to thermodynamic effects, but rather to differences between the gravity-wave dynamics governing vertical velocities over the mountains and the cyclone dynamics governing vertical motions over the oceans and plains.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23534206','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23534206"><span id="translatedtitle">Soil <span class="hlt">warming</span> effect on net ecosystem exchange of carbon dioxide during the transition from <span class="hlt">winter</span> carbon source to spring carbon sink in a temperate urban lawn.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhou, Xiaoping; Wang, Xiaoke; Tong, Lei; Zhang, Hongxing; Lu, Fei; Zheng, Feixiang; Hou, Peiqiang; Song, Wenzhi; Ouyang, Zhiyun</p> <p>2012-01-01</p> <p>The significant <span class="hlt">warming</span> in urban environment caused by the combined effects of global <span class="hlt">warming</span> and heat island has stimulated widely development of urban vegetations. However, it is less known of the climate feedback of urban lawn in <span class="hlt">warmed</span> environment. Soil <span class="hlt">warming</span> effect on net ecosystem exchange (NEE) of carbon dioxide during the transition period from <span class="hlt">winter</span> to spring was investigated in a temperate urban lawn in Beijing, China. The NEE (negative for uptake) under soil <span class="hlt">warming</span> treatment (temperature was about 5 degrees C higher than the ambient treatment as a control) was -0.71 micromol/(m2 x sec), the ecosytem was a CO2 sink under soil <span class="hlt">warming</span> treatment, the lawn ecosystem under the control was a CO2 source (0.13 micromol/(m2 x sec)), indicating that the lawn ecosystem would provide a negative feedback to global <span class="hlt">warming</span>. There was no significant effect of soil <span class="hlt">warming</span> on nocturnal NEE (i.e., ecosystem respiration), although the soil temperature sensitivity (Q10) of ecosystem respiration under soil <span class="hlt">warming</span> treatment was 3.86, much lower than that in the control (7.03). The CO2 uptake was significantly increased by soil <span class="hlt">warming</span> treatment that was attributed to about 100% increase of alpha (apparent quantum yield) and Amax (maximum rate of photosynthesis). Our results indicated that the response of photosynthesis in urban lawn is much more sensitive to global <span class="hlt">warming</span> than respiration in the transition period.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24132503','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24132503"><span id="translatedtitle"><span class="hlt">Wintering</span> birds avoid <span class="hlt">warm</span> sunshine: predation and the costs of foraging in sunlight.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Carr, Jennie M; Lima, Steven L</p> <p>2014-03-01</p> <p><span class="hlt">Wintering</span> birds can gain significant thermal benefits by foraging in direct sunlight. However, exposure to bright sunlight might make birds easier to detect by predators and may also cause visual glare that can reduce a bird's ability to monitor the environment. Thus, birds likely experience a trade-off between the thermal benefits and predation-related costs of foraging in direct sunlight. To examine this possible thermoregulation-predation trade-off, we monitored the behavior of mixed-species flocks of <span class="hlt">wintering</span> emberizid sparrows foraging in alternating strips of sunlight and shade. On average, these sparrows routinely preferred to forage in the shade, despite midday air temperatures as much as 30 °C below their thermoneutral zone. This preference for shade was strongest at relatively high temperatures when the thermal benefits of foraging in sunlight were reduced, suggesting a thermoregulation-predation trade-off. Glare could be reduced if birds faced away from the sun while feeding in direct sunlight, but we found that foraging birds tended to face southward (the direction of the sun). We speculate that other factors, such as the likely direction of predator approach, may explain this southerly orientation, particularly if predators use solar glare to their advantage during an attack. This interpretation is supported by the fact that birds had the weakest southerly orientation on cloudy days. <span class="hlt">Wintering</span> birds may generally avoid foraging in direct sunlight to minimize their risk of predation. However, given the thermal benefits of sunshine, such birds may benefit from foraging in habitats that provide a mosaic of sunlit and shaded microhabitats.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2246132','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2246132"><span id="translatedtitle">Surviving <span class="hlt">extreme</span> polar <span class="hlt">winters</span> by desiccation: clues from Arctic springtail (Onychiurus arcticus) EST libraries</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Clark, Melody S; Thorne, Michael AS; Purać, Jelena; Grubor-Lajšić, Gordana; Kube, Michael; Reinhardt, Richard; Worland, M Roger</p> <p>2007-01-01</p> <p>Background Ice, snow and temperatures of -14°C are conditions which most animals would find difficult, if not impossible, to survive in. However this exactly describes the Arctic <span class="hlt">winter</span>, and the Arctic springtail Onychiurus arcticus regularly survives these <span class="hlt">extreme</span> conditions and re-emerges in the spring. It is able to do this by reducing the amount of water in its body to almost zero: a process that is called "protective dehydration". The aim of this project was to generate clones and sequence data in the form of ESTs to provide a platform for the future molecular characterisation of the processes involved in protective dehydration. Results Five normalised libraries were produced from both desiccating and rehydrating populations of O. arcticus from stages that had previously been defined as potentially informative for molecular analyses. A total of 16,379 EST clones were generated and analysed using Blast and GO annotation. 40% of the clones produced significant matches against the Swissprot and trembl databases and these were further analysed using GO annotation. Extraction and analysis of GO annotations proved an <span class="hlt">extremely</span> effective method for identifying generic processes associated with biochemical pathways, proving more efficient than solely analysing Blast data output. A number of genes were identified, which have previously been shown to be involved in water transport and desiccation such as members of the aquaporin family. Identification of these clones in specific libraries associated with desiccation validates the computational analysis by library rather than producing a global overview of all libraries combined. Conclusion This paper describes for the first time EST data from the arctic springtail (O. arcticus). This significantly enhances the number of Collembolan ESTs in the public databases, providing useful comparative data within this phylum. The use of GO annotation for analysis has facilitated the identification of a wide variety of ESTs</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/2016GeoRL..4311445P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoRL..4311445P"><span id="translatedtitle">The link between <span class="hlt">extreme</span> precipitation and convective organization in a <span class="hlt">warming</span> climate: Global radiative-convective equilibrium simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pendergrass, Angeline G.; Reed, Kevin A.; Medeiros, Brian</p> <p>2016-11-01</p> <p>The rate of increase of <span class="hlt">extreme</span> precipitation in response to global <span class="hlt">warming</span> varies dramatically across climate model simulations, particularly over the tropics, for reasons that have yet to be established. Here we propose one potential mechanism: changing organization of convection with climate. We analyze a set of simulations with the Community Atmosphere Model version 5 with an idealized global radiative-convective equilibrium configuration forced by fixed sea surface temperatures varying in 2° increments from 285 to 307 K. In these simulations, convective organization varies from semiorganized in cold simulations, disorganized in <span class="hlt">warm</span> simulations, and abruptly becomes highly organized at just over 300 K. The change in <span class="hlt">extreme</span> precipitation with <span class="hlt">warming</span> also varies across these simulations, including a large increase at the transition from disorganized to organized convection. We develop an <span class="hlt">extreme</span> precipitation-focused metric for convective organization and use this to explore their connection.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRD..12112282K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRD..12112282K"><span id="translatedtitle">Modulations of aerosol impacts on cloud microphysics induced by the <span class="hlt">warm</span> Kuroshio Current under the East Asian <span class="hlt">winter</span> monsoon</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.; Asano, N.; Nakamura, H.; Sakai, S.; Nagao, T. M.; Nakajima, T. Y.</p> <p>2016-10-01</p> <p>In our previous aircraft observations, the possible influence of high sea surface temperature (SST) along the Kuroshio Current on aerosol-cloud interactions over the western North Pacific was revealed. The cloud droplet number concentration (Nc) was found to increase with decreasing near-surface static stability (NSS), which was evaluated locally as the difference between the SST and surface air temperature (SAT). To explore the spatial and temporal extent to which this <span class="hlt">warm</span> SST influence can be operative, the present study analyzed Nc values estimated from Moderate Resolution Imaging Spectroradiometer (MODIS) satellite measurements. The comparison of the local Nc values between the high and low SST - SAT days revealed a marked increase in Nc (up to a factor of 1.8) along the Kuroshio Current in the southern East China Sea, where particularly high SST - SAT values (up to 8 K) were observed in <span class="hlt">winter</span> under monsoonal cold air outflows from the Asian Continent. This cold airflow destabilizes the atmospheric boundary layer, which leads to enhanced updraft velocities within the well-developed mixed layer and thus greater Nc. The monsoonal northwesterlies also bring a large amount of anthropogenic aerosols from the Asian continent that increase Nc in the first place. These results suggest that the same modulations of cloud microphysics can occur over other <span class="hlt">warm</span> western boundary currents, including the Gulf Stream, under polluted cool continental airflows. Possibilities of influencing the cloud liquid water path are also discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3400059','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3400059"><span id="translatedtitle">Understanding factors influencing vulnerable older people keeping <span class="hlt">warm</span> and well in <span class="hlt">winter</span>: a qualitative study using social marketing techniques</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Lusambili, Adelaide; Homer, Catherine; Abbott, Joanne; Cooke, Joanne Mary; Stocks, Amanda Jayne; McDaid, Kathleen Anne</p> <p>2012-01-01</p> <p>Objectives To understand the influences and decisions of vulnerable older people in relation to keeping <span class="hlt">warm</span> in <span class="hlt">winter</span>. Design A qualitative study incorporating in-depth, semi-structured individual and group interviews, framework analysis and social marketing segmentation techniques. Setting Rotherham, South Yorkshire, UK. Participants 50 older people (>55) and 25 health and social care staff underwent individual interview. The older people also had household temperature measurements. 24 older people and 19 health and social care staff participated in one of the six group interviews. Results Multiple complex factors emerged to explain whether vulnerable older people were able to keep <span class="hlt">warm</span>. These influences combined in various ways that meant older people were not able to or preferred not to access help or change home heating behaviour. Factors influencing behaviours and decisions relating to use of heating, spending money, accessing cheaper tariffs, accessing benefits or asking for help fell into three main categories. These were situational and contextual factors, attitudes and values, and barriers. Barriers included poor knowledge and awareness, technology, disjointed systems and the invisibility of fuel and fuel payment. Findings formed the basis of a social marketing segmentation model used to develop six pen portraits that illustrated how factors that conspire against older people being able to keep <span class="hlt">warm</span>. Conclusions The findings illustrate how and why vulnerable older people may be at risk of a cold home. The pen portraits provide an accessible vehicle and reflective tool to raise the capacity of the NHS in responding to their needs in line with the Cold Weather Plan. PMID:22798252</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5381411','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5381411"><span id="translatedtitle">More-frequent <span class="hlt">extreme</span> northward shifts of eastern Indian Ocean tropical convergence under greenhouse <span class="hlt">warming</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>Weller, Evan; Cai, Wenju; Min, Seung-Ki; Wu, Lixin; Ashok, Karumuri; Yamagata, Toshio</p> <p>2014-01-01</p> <p>The Intertropical Convergence Zone (ITCZ) in the tropical eastern Indian Ocean exhibits strong interannual variability, often co-occurring with positive Indian Ocean Dipole (pIOD) events. During what we identify as an <span class="hlt">extreme</span> ITCZ event, a drastic northward shift of atmospheric convection coincides with an anomalously strong north-minus-south sea surface temperature (SST) gradient over the eastern equatorial Indian Ocean. Such shifts lead to severe droughts over the maritime continent and surrounding islands but also devastating floods in southern parts of the Indian subcontinent. Understanding future changes of the ITCZ is therefore of major scientific and socioeconomic interest. Here we find a more-than-doubling in the frequency of <span class="hlt">extreme</span> ITCZ events under greenhouse <span class="hlt">warming</span>, estimated from climate models participating in the Coupled Model Intercomparison Project phase 5 that are able to simulate such events. The increase is due to a mean state change with an enhanced north-minus-south SST gradient and a weakened Walker Circulation, facilitating smaller perturbations to shift the ITCZ northwards. PMID:25124737</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25124737','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25124737"><span id="translatedtitle">More-frequent <span class="hlt">extreme</span> northward shifts of eastern Indian Ocean tropical convergence under greenhouse <span class="hlt">warming</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Weller, Evan; Cai, Wenju; Min, Seung-Ki; Wu, Lixin; Ashok, Karumuri; Yamagata, Toshio</p> <p>2014-08-15</p> <p>The Intertropical Convergence Zone (ITCZ) in the tropical eastern Indian Ocean exhibits strong interannual variability, often co-occurring with positive Indian Ocean Dipole (pIOD) events. During what we identify as an <span class="hlt">extreme</span> ITCZ event, a drastic northward shift of atmospheric convection coincides with an anomalously strong north-minus-south sea surface temperature (SST) gradient over the eastern equatorial Indian Ocean. Such shifts lead to severe droughts over the maritime continent and surrounding islands but also devastating floods in southern parts of the Indian subcontinent. Understanding future changes of the ITCZ is therefore of major scientific and socioeconomic interest. Here we find a more-than-doubling in the frequency of <span class="hlt">extreme</span> ITCZ events under greenhouse <span class="hlt">warming</span>, estimated from climate models participating in the Coupled Model Intercomparison Project phase 5 that are able to simulate such events. The increase is due to a mean state change with an enhanced north-minus-south SST gradient and a weakened Walker Circulation, facilitating smaller perturbations to shift the ITCZ northwards.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.4752H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.4752H"><span id="translatedtitle">Analysis on seasonal retreat of Siberian high in association with that of the <span class="hlt">extremely</span> cold Siberian air mass from <span class="hlt">winter</span> to spring</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hamaki, Tatsuya; Haga, Yuichi; Kato, Kuranoshin</p> <p>2014-05-01</p> <p>According to Kato et al.(2009), the seasonal increase in surface air temperature in the Japan Islands area attains the maximum due to the rapid weakening of the <span class="hlt">winter</span> time large-scale circulation pattern from late March to early April. Although the rapid decrease in the appearance frequency of the daily Siberian high at that time was pointed out by them, seasonal retreat process of the the Siberian high and the Siberian air mass including in the their day-to-day variations from <span class="hlt">winter</span> to spring have not been systematically understood yet. Thus the present study will examine the above phenomena by using mainly the NCEP/NCAR reanalysis data and the daily weather maps at the surface level provided by JMA. Although the climatological analyses are need in the future, the present study will perform a case study for the several years, 1984(cold <span class="hlt">winter</span>), 2007(<span class="hlt">warm</span> <span class="hlt">winter</span>) and 2011(normal <span class="hlt">winter</span>). The area with high appearance frequency of the surface anticyclone with its center pressure more than 1032hPa (roughly corresponding to the Siberian high) was found around 40N~60N/90~120E (including Lake Baykal area (50~55N/105~110E)) in January and February. Interestingly, the latitude of that high appearance area was not so changed in March. Furthermore its frequency decreased rapidly with its maximum latitude unchanged in April. However, while the high frequency area was mainly located in the colder region with 850hPa temperature (T850) lower than -15 degrees Celsius in January and February wider part of the area with high appearance frequency of the intense anticyclone distributed in the baroclinic zone with T850 higher than -15 degrees Celsius. In April, the -15 degrees Celsius isotherm of T850 moved further northward to ~60N, although the maximum frequency of the anticyclone was seen along ~50N. In addition, although the anticyclone associated with the daily Siberian high showed rather quasi-stationary-like character also in March (as well as in midwinter), the storm track</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27612326','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27612326"><span id="translatedtitle">Press-pulse interactions: effects of <span class="hlt">warming</span>, N deposition, altered <span class="hlt">winter</span> precipitation, and fire on desert grassland community structure and dynamics.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Collins, Scott L; Ladwig, Laura M; Petrie, Matthew D; Jones, Sydney K; Mulhouse, John M; Thibault, James R; Pockman, William T</p> <p>2017-03-01</p> <p>Global environmental change is altering temperature, precipitation patterns, resource availability, and disturbance regimes. Theory predicts that ecological presses will interact with pulse events to alter ecosystem structure and function. In 2006, we established a long-term, multifactor global change experiment to determine the interactive effects of nighttime <span class="hlt">warming</span>, increased atmospheric nitrogen (N) deposition, and increased <span class="hlt">winter</span> precipitation on plant community structure and aboveground net primary production (ANPP) in a northern Chihuahuan Desert grassland. In 2009, a lightning-caused wildfire burned through the experiment. Here, we report on the interactive effects of these global change drivers on pre- and postfire grassland community structure and ANPP. Our nighttime <span class="hlt">warming</span> treatment increased <span class="hlt">winter</span> nighttime air temperatures by an average of 1.1 °C and summer nighttime air temperature by 1.5 °C. Soil N availability was 2.5 times higher in fertilized compared with control plots. Average soil volumetric water content (VWC) in <span class="hlt">winter</span> was slightly but significantly higher (13.0% vs. 11.0%) in plots receiving added <span class="hlt">winter</span> rain relative to controls, and VWC was slightly higher in <span class="hlt">warmed</span> (14.5%) compared with control (13.5%) plots during the growing season even though surface soil temperatures were significantly higher in <span class="hlt">warmed</span> plots. Despite these significant treatment effects, ANPP and plant community structure were highly resistant to these global change drivers prior to the fire. Burning reduced the cover of the dominant grasses by more than 75%. Following the fire, forb species richness and biomass increased significantly, particularly in <span class="hlt">warmed</span>, fertilized plots that received additional <span class="hlt">winter</span> precipitation. Thus, although unburned grassland showed little initial response to multiple ecological presses, our results demonstrate how a single pulse disturbance can interact with chronic alterations in resource availability to increase ecosystem</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMPA21B1869C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMPA21B1869C"><span id="translatedtitle">Communicating Climate Uncertainties: Challenges and Opportunities Related to Spatial Scales, <span class="hlt">Extreme</span> Events, and the <span class="hlt">Warming</span> 'Hiatus'</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Casola, J. H.; Huber, D.</p> <p>2013-12-01</p> <p>Many media, academic, government, and advocacy organizations have achieved sophistication in developing effective messages based on scientific information, and can quickly translate salient aspects of emerging climate research and evolving observations. However, there are several ways in which valid messages can be misconstrued by decision makers, leading them to inaccurate conclusions about the risks associated with climate impacts. Three cases will be discussed: 1) Issues of spatial scale in interpreting climate observations: Local climate observations may contradict summary statements about the effects of climate change on larger regional or global spatial scales. Effectively addressing these differences often requires communicators to understand local and regional climate drivers, and the distinction between a 'signal' associated with climate change and local climate 'noise.' Hydrological statistics in Missouri and California are shown to illustrate this case. 2) Issues of complexity related to <span class="hlt">extreme</span> events: Climate change is typically invoked following a wide range of damaging meteorological events (e.g., heat waves, landfalling hurricanes, tornadoes), regardless of the strength of the relationship between anthropogenic climate change and the frequency or severity of that type of event. Examples are drawn from media coverage of several recent events, contrasting useful and potentially confusing word choices and frames. 3) Issues revolving around climate sensitivity: The so-called 'pause' or 'hiatus' in global <span class="hlt">warming</span> has reverberated strongly through political and business discussions of climate change. Addressing the recent slowdown in <span class="hlt">warming</span> yields an important opportunity to raise climate literacy in these communities. Attempts to use recent observations as a wedge between climate 'believers' and 'deniers' is likely to be counterproductive. Examples are drawn from Congressional testimony and media stories. All three cases illustrate ways that decision</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AtmRe.168...33S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AtmRe.168...33S"><span id="translatedtitle">Changes in <span class="hlt">extreme</span> temperature and precipitation events in the Loess Plateau (China) during 1960-2013 under global <span class="hlt">warming</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sun, Wenyi; Mu, Xingmin; Song, Xiaoyan; Wu, Dan; Cheng, Aifang; Qiu, Bing</p> <p>2016-02-01</p> <p>In recent decades, <span class="hlt">extreme</span> climatic events have been a major issue worldwide. Regional assessments on various climates and geographic regions are needed for understanding uncertainties in <span class="hlt">extreme</span> events' responses to global <span class="hlt">warming</span>. The objective of this study was to assess the annual and decadal trends in 12 <span class="hlt">extreme</span> temperature and 10 <span class="hlt">extreme</span> precipitation indices in terms of intensity, frequency, and duration over the Loess Plateau during 1960-2013. The results indicated that the regionally averaged trends in temperature <span class="hlt">extremes</span> were consistent with global <span class="hlt">warming</span>. The occurrence of <span class="hlt">warm</span> <span class="hlt">extremes</span>, including summer days (SU), tropical nights (TR), <span class="hlt">warm</span> days (TX90), and nights (TN90) and a <span class="hlt">warm</span> spell duration indicator (WSDI), increased by 2.76 (P < 0.01), 1.24 (P < 0.01), 2.60 (P = 0.0003), 3.41 (P < 0.01), and 0.68 (P = 0.0041) days/decade during the period of 1960-2013, particularly, sharp increases in these indices occurred in 1985-2000. Over the same period, the occurrence of cold <span class="hlt">extremes</span>, including frost days (FD), ice days (ID), cold days (TX10) and nights (TN10), and a cold spell duration indicator (CSDI) exhibited decreases of - 3.22 (P < 0.01), - 2.21 (P = 0.0028), - 2.71 (P = 0.0028), - 4.31 (P < 0.01), and - 0.69 (P = 0.0951) days/decade, respectively. Moreover, <span class="hlt">extreme</span> <span class="hlt">warm</span> events in most regions tended to increase while cold indices tended to decrease in the Loess Plateau, but the trend magnitudes of cold <span class="hlt">extremes</span> were greater than those of <span class="hlt">warm</span> <span class="hlt">extremes</span>. The growing season (GSL) in the Loess Plateau was lengthened at a rate of 3.16 days/decade (P < 0.01). Diurnal temperature range (DTR) declined at a rate of - 0.06 °C /decade (P = 0.0931). Regarding the precipitation indices, the annual total precipitation (PRCPTOT) showed no obvious trends (P = 0.7828). The regionally averaged daily rainfall intensity (SDII) exhibited significant decreases (- 0.14 mm/day/decade, P = 0.0158), whereas consecutive dry days (CDD) significantly increased (1.96 days</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ClDy...46.2115R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ClDy...46.2115R"><span id="translatedtitle">Variability in projected elevation dependent <span class="hlt">warming</span> in boreal midlatitude <span class="hlt">winter</span> in CMIP5 climate models and its potential drivers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rangwala, Imtiaz; Sinsky, Eric; Miller, James R.</p> <p>2016-04-01</p> <p>The future rate of climate change in mountains has many potential human impacts, including those related to water resources, ecosystem services, and recreation. Analysis of the ensemble mean response of CMIP5 global climate models (GCMs) shows amplified <span class="hlt">warming</span> in high elevation regions during the cold season in boreal midlatitudes. We examine how the twenty-first century elevation-dependent response in the daily minimum surface air temperature [d(ΔTmin)/dz] varies among 27 different GCMs during <span class="hlt">winter</span> for the RCP 8.5 emissions scenario. The focus is on regions within the northern hemisphere mid-latitude band between 27.5°N and 40°N, which includes both the Rocky Mountains and the Tibetan Plateau/Himalayas. We find significant variability in d(ΔTmin)/dz among the individual models ranging from 0.16 °C/km (10th percentile) to 0.97 °C/km (90th percentile), although nearly all of the GCMs (24 out of 27) show a significant positive value for d(ΔTmin)/dz. To identify some of the important drivers associated with the variability in d(ΔTmin)/dz during <span class="hlt">winter</span>, we evaluate the co-variance between d(ΔTmin)/dz and the differential response of elevation-based anomalies in different climate variables as well as the GCMs' spatial resolution, their global climate sensitivity, and their elevation-dependent free air temperature response. We find that d(ΔTmin)/dz has the strongest correlation with elevation-dependent increases in surface water vapor, followed by elevation-dependent decreases in surface albedo, and a weak positive correlation with the GCMs' free air temperature response.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24921042','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24921042"><span id="translatedtitle">Moving in <span class="hlt">extreme</span> environments: open water swimming in cold and <span class="hlt">warm</span> water.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Tipton, Michael; Bradford, Carl</p> <p>2014-01-01</p> <p>Open water swimming (OWS), either 'wild' such as river swimming or competitive, is a fast growing pastime as well as a part of events such as triathlons. Little evidence is available on which to base high and low water temperature limits. Also, due to factors such as acclimatisation, which disassociates thermal sensation and comfort from thermal state, individuals cannot be left to monitor their own physical condition during swims. Deaths have occurred during OWS; these have been due to not only thermal responses but also cardiac problems. This paper, which is part of a series on 'Moving in <span class="hlt">Extreme</span> Environments', briefly reviews current understanding in pertinent topics associated with OWS. Guidelines are presented for the organisation of open water events to minimise risk, and it is concluded that more information on the responses to immersion in cold and <span class="hlt">warm</span> water, the causes of the individual variation in these responses and the precursors to the cardiac events that appear to be the primary cause of death in OWS events will help make this enjoyable sport even safer.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20380305','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20380305"><span id="translatedtitle">Effects of <span class="hlt">warm</span> <span class="hlt">winter</span> temperature on the abundance and gonotrophic activity of Culex (Diptera: Culicidae) in California.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Reisen, William K; Thiemann, Tara; Barker, Christopher M; Lu, Helen; Carroll, Brian; Fang, Ying; Lothrop, Hugh D</p> <p>2010-03-01</p> <p>Culex tarsalis Coquillett, Cx. quinquefasciatus Say, and Cx. pipiens L. were collected during the <span class="hlt">warm</span> <span class="hlt">winter</span> of 2009 using dry ice-baited and gravid traps and walk-in red boxes positioned in desert, urban, and agricultural habitats in Riverside, Los Angeles, Kern, and Yolo Counties. Temperatures exceeded the preceding 50 yr averages in all locations for most of January, whereas rainfall was absent or below average. Abundance of Culex species in traps during January ranged from 83 to 671% of the prior 5 yr average in all locations. Few females collected resting were in diapause during January based on follicular measurements. Evidence for early season gonotrophic activity included the detection of freshly bloodfed, gravid, and parous females in resting collections, gravid oviposition site-seeking females in gravid female traps, and nulliparous and parous host-seeking females at dry ice-baited traps. Female Culex seemed to employ multiple overwintering strategies in California, including larval and adult quiescence, adult female diapause, and an intermediate situation with adult females collected with enlarged follicles, but without evident vitellogenesis. West Nile, St. Louis, or western equine encephalitis viruses were not detected in 198 pools of adults or 56 pools of adults reared from field-collected immatures collected during January and February 2009. Our preliminary data may provide insight into how climate change may extend the mosquito season in California.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AdAtS..32.1444W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AdAtS..32.1444W"><span id="translatedtitle">Air pollution or global <span class="hlt">warming</span>: Attribution of <span class="hlt">extreme</span> precipitation changes in eastern China—Comments on "Trends of <span class="hlt">extreme</span> precipitation in Eastern China and their possible causes"</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Yuan</p> <p>2015-10-01</p> <p>The recent study "Trends of <span class="hlt">Extreme</span> Precipitation in Eastern China and Their Possible Causes" attributed the observed decrease/increase of light/heavy precipitation in eastern China to global <span class="hlt">warming</span> rather than the regional aerosol effects. However, there exist compelling evidence from previous long-term observations and numerical modeling studies, suggesting that anthropogenic pollution is closely linked to the recent changes in precipitation intensity because of considerably modulated cloud physical properties by aerosols in eastern China. Clearly, a quantitative assessment of the aerosol and greenhouse effects on the regional scale is required to identify the primary cause for the <span class="hlt">extreme</span> precipitation changes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009ClDy...32..969F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009ClDy...32..969F"><span id="translatedtitle">North Pacific cyclonic and anticyclonic transients in a global <span class="hlt">warming</span> context: possible consequences for Western North American daily precipitation and temperature <span class="hlt">extremes</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Favre, Alice; Gershunov, Alexander</p> <p>2009-06-01</p> <p>Trajectories of surface cyclones and anticyclones were constructed using an automated scheme by tracking local minima and maxima of mean daily sea level pressure data in the NCEP-NCAR reanalysis and the Centre National de Recherches Météorologiques coupled global climate Model (CNRM-CM3) SRES A2 integration. Mid-latitude lows and highs traveling in the North Pacific were tracked and daily frequencies were gridded. Transient activity in the CNRM-CM3 historical simulation (1950-1999) was validated against reanalysis. The GCM correctly reproduces <span class="hlt">winter</span> trajectories as well as mean geographical distributions of cyclones and anticyclones over the North Pacific in spite of a general under-estimation of cyclones’ frequency. On inter-annual time scales, frequencies of cyclones and anticyclones vary in accordance with the Aleutian Low (AL) strength. When the AL is stronger (weaker), cyclones are more (less) numerous over the central and eastern North Pacific, while anticyclones are significantly less (more) numerous over this region. The action of transient cyclones and anticyclones over the central and eastern North Pacific determines seasonal climate over the West Coast of North America, and specifically, <span class="hlt">winter</span> weather over California. Relationships between <span class="hlt">winter</span> cyclone/anticyclone behavior and daily precipitation/cold temperature <span class="hlt">extremes</span> over Western North America (the West) were examined and yielded two simple indices summarizing North Pacific transient activity relevant to regional climates. These indices are strongly related to the observed inter-annual variability of daily precipitation and cold temperature <span class="hlt">extremes</span> over the West as well as to large scale seasonally averaged near surface climate conditions (e.g., air temperature at 2 m and wind at 10 m). In fact, they represent the synoptic links that accomplish the teleconnections. Comparison of patterns derived from NCEP-NCAR and CNRM-CM3 revealed that the model reproduces links between cyclone</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.A34D..03T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.A34D..03T"><span id="translatedtitle">Pseudo-global <span class="hlt">warming</span> controls on the intensity and morphology of <span class="hlt">extreme</span> convective storm events</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Trapp, R. J.</p> <p>2015-12-01</p> <p>This research seeks to answer the basic question of how current-day <span class="hlt">extreme</span> convective storm events might be represented under future anthropogenic climate change. We adapt the "pseudo-global <span class="hlt">warming</span>" (PGW) methodology employed by Lackmann (2013, 2015) and others, who have investigated flooding and tropical cyclone events under climate change. Here, we exploit coupled atmosphere-ocean GCM data contributed to the CMIP5 archive, and take the mean 3D atmospheric state simulated during May 1990-1999 and subtract it from that simulated during May 2090-2099. Such 3D changes in temperature, humidity, geopotential height, and winds are added to synoptic/meso-scale analyses (NAM-ANL) of specific events, and this modified atmospheric state is then used for initial and boundary conditions for real-data WRF model simulations of the events at high resolution. Comparison of an ensemble of these simulations with control (CTRL) simulations facilitates assessment of PGW effects. In contrast to the robust development of supercellular convection in our CTRL simulations, the combined effects of increased CIN and decreased forcing under PGW led to a failure of convection initiation in many of our ensemble members. Those members that had sufficient matching between the CIN and forcing tended to generate stronger convective updrafts than in the CTRL simulations, because of the relatively higher CAPE under PGW. And, the members with enhanced updrafts also tended to have enhanced vertical rotation. In fact, such mesocyclonic rotation and attendant supercellular morphology were even found in simulations that were driven with PGW-reduced environmental wind shear.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ClDy...48.1401W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ClDy...48.1401W"><span id="translatedtitle">The impact of ENSO and the NAO on <span class="hlt">extreme</span> <span class="hlt">winter</span> precipitation in North America in observations and regional climate models</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Whan, Kirien; Zwiers, Francis</p> <p>2017-03-01</p> <p>The relationship between <span class="hlt">winter</span> precipitation in North America and indices of the North Atlantic Oscillation (NAO) and El Niño-Southern Oscillation (ENSO) is evaluated using non-stationary generalized <span class="hlt">extreme</span> value distributions with the indices as covariates. Both covariates have a statistically significant influence on precipitation that is well simulated by two regional climate models (RCMs), CanRCM4 and CRCM5. The observed influence of the NAO on <span class="hlt">extreme</span> precipitation is largest in eastern North America, with the likelihood of a negative phase <span class="hlt">extreme</span> rainfall event decreased in the north and increased in the south under the positive phase of the NAO. This pattern is generally well simulated by the RCMs although there are some differences in the extent of influence, particularly south of the Great Lakes. A La Niña-magnitude <span class="hlt">extreme</span> event is more likely to occur under El Niño conditions in California and the southern United States, and less likely in most of Canada and a region south of the Great Lakes. This broad pattern is also simulated well by the RCMs but they do not capture the increased likelihood in California. In some places the <span class="hlt">extreme</span> precipitation response in the RCMs to external forcing from a covariate is of the opposite sign, despite use of the same lateral boundary conditions and dynamical core. This demonstrates the importance of model physics for teleconnections to <span class="hlt">extreme</span> precipitation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/14510210','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/14510210"><span id="translatedtitle">A computer simulation of the oxygen balance in a cold climate <span class="hlt">winter</span> storage WSP during the critical spring <span class="hlt">warm</span>-up period.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Banks, C J; Koloskov, G B; Lock, A C; Heaven, S</p> <p>2003-01-01</p> <p>The paper considers factors that determine the oxygen balance in <span class="hlt">extreme</span> climate waste stabilisation ponds during the critical spring <span class="hlt">warm</span>-up period. At this time BOD load on the pond is a maximum, due to accumulation of wastewater under the ice during the <span class="hlt">winter</span>. The paper describes the operation of a typical cold climate WSP and the events leading to a balanced steady state system as spring develops into summer. A mathematical model to simulate conditions within a batch fed experimental pond over the transient period is described. To model temperature changes in the water body experimental data were fitted to a generalised equation based on diurnal fluctuations in air temperature. The results are plotted in a normalised form and show the diurnal fluctuation and time lapse as the depth of the pond increases. Maximum daily water temperature lags behind maximum light intensity. Bacterial growth is simulated by a Monod kinetic model in which growth rate depends on initial substrate concentration; temperature compensation is applied using a temperature activity coefficient. Oxygen utilisation is calculated from substrate removal. Algal growth rate is more complicated as it is affected by temperature and light availability. Algal oxygen production potential is considered in terms of its primary metabolite yield, which is then used in a Monod equation to estimate the growth rate. The model uses a mass balance approach to determine dissolved oxygen concentration in the pond. The model is still in a simple form but shows reasonable agreement, in terms of events and time lapses, to measured parameters in experimental ponds recovering from ice cover.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24903191','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24903191"><span id="translatedtitle">Bacterial responses to fluctuations and <span class="hlt">extremes</span> in temperature and brine salinity at the surface of Arctic <span class="hlt">winter</span> sea ice.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ewert, Marcela; Deming, Jody W</p> <p>2014-08-01</p> <p>Wintertime measurements near Barrow, Alaska, showed that bacteria near the surface of first-year sea ice and in overlying saline snow experience more <span class="hlt">extreme</span> temperatures and salinities, and wider fluctuations in both parameters, than bacteria deeper in the ice. To examine impacts of such conditions on bacterial survival, two Arctic isolates with different environmental tolerances were subjected to <span class="hlt">winter</span>-freezing conditions, with and without the presence of organic solutes involved in osmoprotection: proline, choline, or glycine betaine. Obligate psychrophile Colwellia psychrerythraea strain 34H suffered cell losses under all treatments, with maximal loss after 15-day exposure to temperatures fluctuating between -7 and -25 °C. Osmoprotectants significantly reduced the losses, implying that salinity rather than temperature <span class="hlt">extremes</span> presents the greater stress for this organism. In contrast, psychrotolerant Psychrobacter sp. strain 7E underwent miniaturization and fragmentation under both fluctuating and stable-freezing conditions, with cell numbers increasing in most cases, implying a different survival strategy that may include enhanced dispersal. Thus, the composition and abundance of the bacterial community that survives in <span class="hlt">winter</span> sea ice may depend on the extent to which overlying snow buffers against <span class="hlt">extreme</span> temperature and salinity conditions and on the availability of solutes that mitigate osmotic shock, especially during melting.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMGC44A..07K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMGC44A..07K"><span id="translatedtitle">Global and Regional Variations in Mean Temperature and <span class="hlt">Warm</span> <span class="hlt">Extremes</span> in Large-Member Historical AGCM Simulation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kamae, Y.; Shiogama, H.; Imada, Y.; Mori, M.; Arakawa, O.; Mizuta, R.; Yoshida, K.; Ishii, M.; Watanabe, M.; Kimoto, M.; Ueda, H.</p> <p>2015-12-01</p> <p>Frequency of heat <span class="hlt">extremes</span> during the summer season has increased continuously since the late 20th century despite the global <span class="hlt">warming</span> hiatus. In previous studies, anthropogenic influences, natural variation in sea surface temperature (SST), and internal atmospheric variabilities are suggested to be factors contributing to the increase in the frequency of <span class="hlt">warm</span> <span class="hlt">extremes</span>. Here 100-member ensemble historical simulations were performed (called "database for Probabilistic Description of Future climate"; d4PDF) to examine physical mechanisms responsible for the increasing hot summers and attribute to the anthropogenic influences or natural climate variability. 60km resolution MRI-AGCM ensemble simulations can reproduce historical variations in the mean temperature and <span class="hlt">warm</span> <span class="hlt">extremes</span>. Natural SST variability in the Pacific and Atlantic Oceans contribute to the decadal variation in the frequency of hot summers in the Northern Hemisphere middle latitude. For example, the surface temperature over western North America, including California, is largely influenced by anomalous atmospheric circulation pattern associated with Pacific SST variability. Future projections based on anomalous SST patterns derived from coupled climate model simulations will also be introduced.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27591579','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27591579"><span id="translatedtitle">Sensitivity of soil carbon fractions and their specific stabilization mechanisms to <span class="hlt">extreme</span> soil <span class="hlt">warming</span> in a subarctic grassland.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Poeplau, Christopher; Kätterer, Thomas; Leblans, Niki I W; Sigurdsson, Bjarni D</p> <p>2017-03-01</p> <p>Terrestrial carbon cycle feedbacks to global <span class="hlt">warming</span> are major uncertainties in climate models. For in-depth understanding of changes in soil organic carbon (SOC) after soil <span class="hlt">warming</span>, long-term responses of SOC stabilization mechanisms such as aggregation, organo-mineral interactions and chemical recalcitrance need to be addressed. This study investigated the effect of 6 years of geothermal soil <span class="hlt">warming</span> on different SOC fractions in an unmanaged grassland in Iceland. Along an <span class="hlt">extreme</span> <span class="hlt">warming</span> gradient of +0 to ~+40 °C, we isolated five fractions of SOC that varied conceptually in turnover rate from active to passive in the following order: particulate organic matter (POM), dissolved organic carbon (DOC), SOC in sand and stable aggregates (SA), SOC in silt and clay (SC-rSOC) and resistant SOC (rSOC). Soil <span class="hlt">warming</span> of 0.6 °C increased bulk SOC by 22 ± 43% (0-10 cm soil layer) and 27 ± 54% (20-30 cm), while further <span class="hlt">warming</span> led to exponential SOC depletion of up to 79 ± 14% (0-10 cm) and 74 ± 8% (20-30) in the most <span class="hlt">warmed</span> plots (~+40 °C). Only the SA fraction was more sensitive than the bulk soil, with 93 ± 6% (0-10 cm) and 86 ± 13% (20-30 cm) SOC losses and the highest relative enrichment in (13) C as an indicator for the degree of decomposition (+1.6 ± 1.5‰ in 0-10 cm and +1.3 ± 0.8‰ in 20-30 cm). The SA fraction mass also declined along the <span class="hlt">warming</span> gradient, while the SC fraction mass increased. This was explained by deactivation of aggregate-binding mechanisms. There was no difference between the responses of SC-rSOC (slow-cycling) and rSOC (passive) to <span class="hlt">warming</span>, and (13) C enrichment in rSOC was equal to that in bulk soil. We concluded that the sensitivity of SOC to <span class="hlt">warming</span> was not a function of age or chemical recalcitrance, but triggered by changes in biophysical stabilization mechanisms, such as aggregation.</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/2016GeoRL..43.1340W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoRL..43.1340W"><span id="translatedtitle">Detecting climate signals in precipitation <span class="hlt">extremes</span> from TRMM (1998-2013)—Increasing contrast between wet and dry <span class="hlt">extremes</span> during the "global <span class="hlt">warming</span> hiatus"</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wu, Huey-Tzu Jenny; Lau, William K.-M.</p> <p>2016-02-01</p> <p>We investigate changes in daily precipitation <span class="hlt">extremes</span> using Tropical Rainfall Measuring Mission (TRMM) data (1998-2013), which coincides with the "global <span class="hlt">warming</span> hiatus." Results show a change in probability distribution functions of local precipitation events (LPEs) during this period consistent with previous global <span class="hlt">warming</span> studies, indicating increasing contrast between wet and dry <span class="hlt">extremes</span>, with more intense LPE, less moderate LPE, and more dry (no rain) days globally. Analyses for land and ocean separately reveal more complex and nuanced changes over land, characterized by a strong positive trend (+12.0% per decade, 99% confidence level (c.l.)) in frequency of <span class="hlt">extreme</span> LPEs over the Northern Hemisphere extratropics during the wet season but a negative global trend (-6.6% per decade, 95% c.l.) during the dry season. A significant global drying trend (3.2% per decade, 99% c.l.) over land is also found during the dry season. Regions of pronounced increased dry events include western and central U.S., northeastern Asia, and Southern Europe/Mediterranean.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20160002960&hterms=Global+warming&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DGlobal%2Bwarming','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20160002960&hterms=Global+warming&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DGlobal%2Bwarming"><span id="translatedtitle">Detecting Climate Signals in Precipitation <span class="hlt">Extremes</span> from TRMM (1998-2013) - Increasing Contrast Between Wet and Dry <span class="hlt">Extremes</span> During the "Global <span class="hlt">Warming</span> Hiatus"</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wu, Huey-Tzu Jenny; Lau, William K.-M.</p> <p>2016-01-01</p> <p>We investigate changes in daily precipitation <span class="hlt">extremes</span> using Tropical Rainfall Measuring Mission (TRMM) data (1998-2013), which coincides with the "global <span class="hlt">warming</span> hiatus." Results show a change in probability distribution functions of local precipitation events (LPEs) during this period consistent with previous global <span class="hlt">warming</span> studies, indicating increasing contrast between wet and dry <span class="hlt">extremes</span>, with more intense LPE, less moderate LPE, and more dry (no rain) days globally. Analyses for land and ocean separately reveal more complex and nuanced changes over land, characterized by a strong positive trend (+12.0% per decade, 99% confidence level (c.l.)) in frequency of <span class="hlt">extreme</span> LPEs over the Northern Hemisphere extratropics during the wet season but a negative global trend (-6.6% per decade, 95% c.l.) during the dry season. A significant global drying trend (3.2% per decade, 99% c.l.) over land is also found during the dry season. Regions of pronounced increased dry events include western and central U.S., northeastern Asia, and Southern Europe/Mediterranean.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JGRC..118.6838B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JGRC..118.6838B"><span id="translatedtitle">Near cessation of Eighteen Degree Water renewal in the western North Atlantic in the <span class="hlt">warm</span> <span class="hlt">winter</span> of 2011-2012</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Billheimer, Sam; Talley, Lynne D.</p> <p>2013-12-01</p> <p>The <span class="hlt">winter</span> of 2011-2012 was a particularly weak season for the renewal of "Eighteen Degree Water" (EDW), the Subtropical Mode Water of the western North Atlantic, as demonstrated by Argo and repeat hydrography. Weak, late <span class="hlt">winter</span> buoyancy forcing produced shallower than usual <span class="hlt">winter</span> mixed layers throughout the subtropical gyre, failing to thoroughly ventilate the underlying mode water, and can likely be attributed to the coinciding high, positive phase of the North Atlantic Oscillation (NAO). The only region where EDW was renewed was in the far northeastern Sargasso Sea where it is understood that the Gulf Stream plays a central role in formation; no EDW formed over the large regions of the gyre where deep <span class="hlt">winter</span> mixed layers driven by surface buoyancy loss normally create EDW. The present investigation evaluates 2011-2012 <span class="hlt">winter</span> buoyancy content anomalies, surface buoyancy fluxes, and advection of buoyancy via the Gulf Stream and compares them with the previous seven <span class="hlt">winters</span> that exhibited more vigorous EDW formation. The weak 2011-2012 formation did not result from increased Gulf Stream heat advection, and was also not driven by preconditioning as the buoyancy content of the region prior to the onset of <span class="hlt">winter</span> forcing was not unusually high. Rather, the weak formation resulted from climatologically weak surface cooling late in <span class="hlt">winter</span>. The <span class="hlt">winter</span> of 2007-2008 also experienced particularly weak EDW formation under similar conditions, including a high NAO and weak late <span class="hlt">winter</span> surface cooling.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.6780B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.6780B"><span id="translatedtitle"><span class="hlt">Extreme</span> <span class="hlt">Winter</span> Cyclones in the North Atlantic in a Last Millennium Climate Simulation with CESM1.0.1</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Blumer, Sandro R.; Raible, Christoph C.; Lehner, Flavio; Stocker, Thomas F.</p> <p>2016-04-01</p> <p><span class="hlt">Extreme</span> cyclones and their associated impacts are a major threat to mankind, as they often result in heavy precipitation events and severe winds. The last millennium is closest to the Anthropocene and has the best coverage of paleo-climatic information. Therefore, it can serve as a test bed for estimating natural forcing variations beyond the recent observational period and can deliver insight into the frequency and intensity of <span class="hlt">extreme</span> events, including strong cyclones and their dependency on internal variability and external forcing. The aim of this study is to investigate how the frequency and intensity of <span class="hlt">extreme</span> cyclones in the North Atlantic have changed in the last millennium, and investigate phases which deviate more than one standard deviation. In particular the changes during prolonged cold and <span class="hlt">warm</span> periods and the 21st century are analysed to assess the external forcing imprint. We use a comprehensive fully-coupled transient climate simulation of the last millennium (AD 1000-2100) with a relatively high spatial (0.9x1.25 degrees) resolution. Cyclones are then detected and tracked in 12-hourly output using an algorithm that is based on the geopotential height field on 1000 hPa. In addition to the tracking, a Gaussian function is fitted to the depressions in the geopotential height field at every time step in order to have a geometric representation of the low pressure systems. Additionally, two intensity indices for <span class="hlt">extreme</span> cyclones are defined: the 90 percentile of the mean gradient in geopotential and the 90 percentile of the precipitation within a radius of one standard deviation of the approximated Gaussian function around the cyclone. These criteria consider two aspects of cyclone's intensity: <span class="hlt">extremes</span> in wind and precipitation. A 30-yr running window is applied to the entire simulation. Within each window the cyclone frequency and the indices for <span class="hlt">extreme</span> wind and <span class="hlt">extreme</span> precipitation cyclones are averaged. This analysis reveals decadal to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010ThApC.100..163B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010ThApC.100..163B"><span id="translatedtitle">European floods during the <span class="hlt">winter</span> 1783/1784: scenarios of an <span class="hlt">extreme</span> event 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>Brázdil, Rudolf; Demarée, Gaston R.; Deutsch, Mathias; Garnier, Emmanuel; Kiss, Andrea; Luterbacher, Jürg; MacDonald, Neil; Rohr, Christian; Dobrovolný, Petr; Kolář, Petr; Chromá, Kateřina</p> <p>2010-03-01</p> <p>The Lakagígar eruption in Iceland during 1783 was followed by the severe <span class="hlt">winter</span> of 1783/1784, which was characterised by low temperatures, frozen soils, ice-bound watercourses and high rates of snow accumulation across much of Europe. Sudden <span class="hlt">warming</span> coupled with rainfall led to rapid snowmelt, resulting in a series of flooding phases across much of Europe. The first phase of flooding occurred in late December 1783-early January 1784 in England, France, the Low Countries and historical Hungary. The second phase at the turn of February-March 1784 was of greater extent, generated by the melting of an unusually large accumulation of snow and river ice, affecting catchments across France and Central Europe (where it is still considered as one of the most disastrous known floods), throughout the Danube catchment and in southeast Central Europe. The third and final phase of flooding occurred mainly in historical Hungary during late March and early April 1784. The different impacts and consequences of the above floods on both local and regional scales were reflected in the economic and societal responses, material damage and human losses. The <span class="hlt">winter</span> of 1783/1784 can be considered as typical, if severe, for the Little Ice Age period across much of Europe.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23086507','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23086507"><span id="translatedtitle">Nocturnal loss of body reserves reveals high survival risk for subordinate great tits <span class="hlt">wintering</span> at <span class="hlt">extremely</span> low ambient temperatures.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Krams, Indrikis; Cīrule, Dina; Vrublevska, Jolanta; Nord, Andreas; Rantala, Markus J; Krama, Tatjana</p> <p>2013-06-01</p> <p><span class="hlt">Winter</span> acclimatization in birds is a complex of several strategies based on metabolic adjustment accompanied by long-term management of resources such as fattening. However, <span class="hlt">wintering</span> birds often maintain fat reserves below their physiological capacity, suggesting a cost involved with excessive levels of reserves. We studied body reserves of roosting great tits in relation to their dominance status under two contrasting temperature regimes to see whether individuals are capable of optimizing their survival strategies under <span class="hlt">extreme</span> environmental conditions. We predicted less pronounced loss of body mass and body condition and lower rates of overnight mortality in dominant great tits at both mild and <span class="hlt">extremely</span> low ambient temperatures, when ambient temperature dropped down to -43 °C. The results showed that dominant great tits consistently maintained lower reserve levels than subordinates regardless of ambient temperature. However, dominants responded to the rising risk of starvation under low temperatures by increasing their body reserves, whereas subdominant birds decreased reserve levels in harsh conditions. Yet, their losses of body mass and body reserves were always lower than in subordinate birds. None of the dominant great tits were found dead, while five young females and one adult female were found dead in nest boxes during cold spells when ambient temperatures dropped down to -43 °C. The dead great tits lost up to 23.83 % of their evening body mass during cold nights while surviving individuals lost on average 12.78 % of their evening body mass. Our results show that fattening strategies of great tits reflect an adaptive role of <span class="hlt">winter</span> fattening which is sensitive to changes in ambient temperatures and differs among individuals of different social ranks.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AdAtS..33.1005D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AdAtS..33.1005D"><span id="translatedtitle">Abrupt summer <span class="hlt">warming</span> and changes in temperature <span class="hlt">extremes</span> over Northeast Asia since the mid-1990s: Drivers and physical processes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dong, Buwen; Sutton, Rowan T.; Chen, Wei; Liu, Xiaodong; Lu, Riyu; Sun, Ying</p> <p>2016-09-01</p> <p>This study investigated the drivers and physical processes for the abrupt decadal summer surface <span class="hlt">warming</span> and increases in hot temperature <span class="hlt">extremes</span> that occurred over Northeast Asia in the mid-1990s. Observations indicate an abrupt increase in summer mean surface air temperature (SAT) over Northeast Asia since the mid-1990s. Accompanying this abrupt surface <span class="hlt">warming</span>, significant changes in some temperature <span class="hlt">extremes</span>, characterized by increases in summer mean daily maximum temperature (Tmax), daily minimum temperature (Tmin), annual hottest day temperature (TXx), and annual warmest night temperature (TNx) were observed. There were also increases in the frequency of summer days (SU) and tropical nights (TR). Atmospheric general circulation model experiments forced by changes in sea surface temperature (SST)/sea ice extent (SIE), anthropogenic greenhouse gas (GHG) concentrations, and anthropogenic aerosol (AA) forcing, relative to the period 1964-93, reproduced the general patterns of observed summer mean SAT changes and associated changes in temperature <span class="hlt">extremes</span>, although the abrupt decrease in precipitation since the mid-1990s was not simulated. Additional model experiments with different forcings indicated that changes in SST/SIE explained 76% of the area-averaged summer mean surface <span class="hlt">warming</span> signal over Northeast Asia, while the direct impact of changes in GHG and AA explained the remaining 24% of the surface <span class="hlt">warming</span> signal. Analysis of physical processes indicated that the direct impact of the changes in AA (through aerosol-radiation and aerosol-cloud interactions), mainly related to the reduction of AA precursor emissions over Europe, played a dominant role in the increase in TXx and a similarly important role as SST/SIE changes in the increase in the frequency of SU over Northeast Asia via AA-induced coupled atmosphere-land surface and cloud feedbacks, rather than through a direct impact of AA changes on cloud condensation nuclei. The modelling results also imply</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28214115','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28214115"><span id="translatedtitle"><span class="hlt">Warm</span> summers and moderate <span class="hlt">winter</span> precipitation boost Rhododendron ferrugineum L. growth in the Taillefer massif (French Alps).</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Francon, L; Corona, C; Roussel, E; Lopez Saez, J; Stoffel, M</p> <p>2017-05-15</p> <p>Rhododendron ferrugineum L. is a widespread dwarf shrub species growing in high-elevation, alpine environments of the Western European Alps. For this reason, analysis of its growth rings offers unique opportunities to push current dendrochronological networks into <span class="hlt">extreme</span> environments and way beyond the treeline. Given that different species of the same genus have been successfully used in tree-ring investigations, notably in the Himalayas where Rhododendron spp. has proven to be a reliable climate proxy, this study aims at (i) evaluating the dendroclimatological potential of R. ferrugineum and at (ii) determining the major limiting climate factor driving its growth. To this end, 154 cross-sections from 36 R. ferrugineum individuals have been sampled above local treelines and at elevations from 1800 to 2100masl on northwest-facing slopes of the Taillefer massif (French Alps). We illustrate a 195-year-long standard chronology based on growth-ring records from 24 R. ferrugineum individuals, and document that the series is well-replicated for almost one century (1920-2015) with an Expressed Population Signal (EPS) >0.85. Analyses using partial and moving 3-months correlation functions further highlight that growth of R. ferrugineum is governed by temperatures during the growing season (May-July), with increasingly higher air temperatures favoring wider rings, a phenomenon which is well known from dwarf shrubs growing in circum-arctic tundra ecosystems. Similarly, the negative effect of January-February precipitation on radial growth of R. ferrugineum, already observed in the Alps on juniper shrubs, is interpreted as a result of shortened growing seasons following snowy <span class="hlt">winters</span>. We conclude that the strong and unequivocal signals recorded in the fairly long R. ferrugineum chronologies can indeed be used for climate-growth studies as well as for the reconstruction of climatic fluctuations in Alpine regions beyond the upper limits of present-day forests.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23161252','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23161252"><span id="translatedtitle">Improving conservation of Florida manatees (Trichechus manatus latirostris): conceptualization and contributions toward a regional <span class="hlt">warm</span>-water network management strategy for sustainable <span class="hlt">winter</span> habitat.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Flamm, Richard Owen; Reynolds, John Elliot; Harmak, Craig</p> <p>2013-01-01</p> <p>We used southwestern Florida as a case study to lay the groundwork for an intended and organized decision-making process for managing <span class="hlt">warm</span>-water habitat needed by endangered manatees to survive <span class="hlt">winters</span> in Florida. Scientists and managers have prioritized (a) projecting how the network of <span class="hlt">warm</span>-water sites will change over the next 50 years as <span class="hlt">warmed</span> industrial discharges may expire and as flows of natural springs are reduced through redirection of water for human uses, and (b) mitigating such changes to prevent undue consequences to manatees. Given the complexities introduced by manatee ecology; agency organizational structure; shifting public demands; fluctuating resource availability; and managing within interacting cultural, social, political, and environmental contexts, it was clear that a structured decision process was needed. To help promote such a process, we collected information relevant to future decisions including maps of known and suspected <span class="hlt">warm</span>-water sites and prototyped a characterization of sites and networks. We propose steps that would lead to models that might serve as core tools in manatee/<span class="hlt">warm</span>-water decision-making, and we summarized topics relevant for informed decision-making (e.g., manatee spatial cognition, risk of cold-stress morbidity and mortality, and human dimensions). A major impetus behind this effort is to ensure proactively that robust modeling tools are available well in advance of the anticipated need for a critical management decision.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EnMan..51..154F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EnMan..51..154F"><span id="translatedtitle">Improving Conservation of Florida Manatees ( Trichechus manatus latirostris): Conceptualization and Contributions Toward a Regional <span class="hlt">Warm</span>-Water Network Management Strategy for Sustainable <span class="hlt">Winter</span> Habitat</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Flamm, Richard Owen; Reynolds, John Elliot; Harmak, Craig</p> <p>2013-01-01</p> <p>We used southwestern Florida as a case study to lay the groundwork for an intended and organized decision-making process for managing <span class="hlt">warm</span>-water habitat needed by endangered manatees to survive <span class="hlt">winters</span> in Florida. Scientists and managers have prioritized (a) projecting how the network of <span class="hlt">warm</span>-water sites will change over the next 50 years as <span class="hlt">warmed</span> industrial discharges may expire and as flows of natural springs are reduced through redirection of water for human uses, and (b) mitigating such changes to prevent undue consequences to manatees. Given the complexities introduced by manatee ecology; agency organizational structure; shifting public demands; fluctuating resource availability; and managing within interacting cultural, social, political, and environmental contexts, it was clear that a structured decision process was needed. To help promote such a process, we collected information relevant to future decisions including maps of known and suspected <span class="hlt">warm</span>-water sites and prototyped a characterization of sites and networks. We propose steps that would lead to models that might serve as core tools in manatee/<span class="hlt">warm</span>-water decision-making, and we summarized topics relevant for informed decision-making (e.g., manatee spatial cognition, risk of cold-stress morbidity and mortality, and human dimensions). A major impetus behind this effort is to ensure proactively that robust modeling tools are available well in advance of the anticipated need for a critical management decision.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2712400','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2712400"><span id="translatedtitle">Is Shade Beneficial for Mediterranean Shrubs Experiencing Periods of <span class="hlt">Extreme</span> Drought and Late-<span class="hlt">winter</span> Frosts?</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Valladares, Fernando; Zaragoza-Castells, Joana; Sánchez-Gómez, David; Matesanz, Silvia; Alonso, Beatriz; Portsmuth, Angelika; Delgado, Antonio; Atkin, Owen K.</p> <p>2008-01-01</p> <p>Background and Aims Plants are naturally exposed to multiple, frequently interactive stress factors, most of which are becoming more severe due to global change. Established plants have been reported to facilitate the establishment of juvenile plants, but net effects of plant–plant interactions are difficult to assess due to complex interactions among environmental factors. An investigation was carried out in order to determine how two dominant evergreen shrubs (Quercus ilex and Arctostaphylos uva-ursi) co-occurring in continental, Mediterranean habitats respond to multiple abiotic stresses and whether the shaded understorey conditions ameliorate the negative effects of drought and <span class="hlt">winter</span> frosts on the physiology of leaves. Methods Microclimate and ecophysiology of sun and shade plants were studied at a continental plateau in central Spain during 2004–2005, with 2005 being one of the driest and hottest years on record; several late-<span class="hlt">winter</span> frosts also occurred in 2005. Key Results Daytime air temperature and vapour pressure deficit were lower in the shade than in the sun, but soil moisture was also lower in the shade during the spring and summer of 2005, and night-time temperatures were higher in the shade. Water potential, photochemical efficiency, light-saturated photosynthesis, stomatal conductance and leaf 13C composition differed between sun and shade individuals throughout the seasons, but differences were species specific. Shade was beneficial for leaf-level physiology in Q. ilex during <span class="hlt">winter</span>, detrimental during spring for both species, and of little consequence in summer. Conclusions The results suggest that beneficial effects of shade can be eclipsed by reduced soil moisture during dry years, which are expected to be more frequent in the most likely climate change scenarios for the Mediterranean region. PMID:18819947</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AGUFM.A53E0255Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AGUFM.A53E0255Y"><span id="translatedtitle">Responses to Global <span class="hlt">Warming</span> Over the Eastern and Central Tibetan Plateau as Reflected in Day-time and Night-time Temperatures, <span class="hlt">Extreme</span> Temperature Events, and Growing Season Length During 1961-2003</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yin, Z.; Liu, X.; Shao, X.</p> <p>2006-12-01</p> <p>This study examines the trends and variation patterns in daily maximum (day-time) and minimum (night-time) temperatures (hereafter referred to as Tm and Tn), <span class="hlt">extreme</span> events, and growing season lengths over the eastern and central Tibetan Plateau (TP), in comparison with the results from other regions. Data during the period 1961-2003 from 66 weather stations over the eastern and central TP with elevations above 2000 m are used in this study, after going through rigorous quality assessment/quality control procedures. Statistically significant <span class="hlt">warming</span> trends are identified in various measures of the temperature regime, especially in night- time temperatures, <span class="hlt">extreme</span> <span class="hlt">warm</span>/cold events, and diurnal temperature range (DTR). We find that the trends in Tn and Tm display distinct spatial patterns in the study region. The <span class="hlt">warming</span> trends in <span class="hlt">winter</span> night-time temperatures are among the highest when compared with studies conducted in other regions. Our results also confirm the asymmetric pattern of greater <span class="hlt">warming</span> trends in minimum or night-time temperatures as compared to the day-time temperatures, which reduces the DTR in the region. Based on the time-varying percentiles of Tn and Tm, prominent <span class="hlt">warming</span> trends are found in Tn during cold season months across the relative temperature scale of both <span class="hlt">warm</span> and cold events. The <span class="hlt">warming</span> in night-time temperatures causes the number of frost days to decrease significantly and the number of <span class="hlt">warm</span> days to increase. The mean length of growing season has increased by approximately 17 days during the 43-year study period for the region. Most of the record-setting months for cold events are found in the earlier part of the study period, while that of the <span class="hlt">warm</span> events have occurred mostly in the later half, especially since the 1990s. The changes in the temperature regime in this region may have brought regional-specific impacts on the ecosystems. It is found that grain production in Qinghai Province, located in the northeastern part of the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRC..121.6331I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRC..121.6331I"><span id="translatedtitle">Circulation and haline structure of a microtidal bay in the Sea of Japan influenced by the <span class="hlt">winter</span> monsoon and the Tsushima <span class="hlt">Warm</span> Current</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Itoh, Sachihiko; Kasai, Akihide; Takeshige, Aigo; Zenimoto, Kei; Kimura, Shingo; Suzuki, Keita W.; Miyake, Yoichi; Funahashi, Tatsuhiro; Yamashita, Yoh; Watanabe, Yoshiro</p> <p>2016-08-01</p> <p>Mooring and hydrographic surveys were conducted in Tango Bay, a microtidal region of freshwater influence (ROFI) in the Sea of Japan, in order to clarify the circulation pattern in the bay and its driving forces. Monthly mean velocity records at four stations revealed an inflow and outflow at the eastern and northern openings of the bay, respectively, indicating an anticyclonic circulation across the bay mouth. The circulation was significantly intensified in <span class="hlt">winter</span>, in accordance with the prevailing NW wind component of the <span class="hlt">winter</span> monsoon. The anticyclonic circulation at the bay mouth was connected to an estuarine circulation that was evident near the mouth of the Yura River at the bay head. Surface salinity just offshore of the river mouth was closely related to the Yura River discharge, whereas in lower layers the offshore water had a stronger influence on salinity. Prior to a seasonal increase in the Yura River discharge, summer salinity decreased markedly through the water column in Tango Bay, possibly reflecting intrusion of the Changjiang Diluted Water transported by the Tsushima <span class="hlt">Warm</span> Current. In contrast with the traditional assumption that estuarine circulation is controlled mainly by river discharge and tidal forcing, the circulation in Tango Bay is strongly influenced by seasonal wind and the Tsushima <span class="hlt">Warm</span> Current. The narrow shelf may be responsible for the strong influence of the Tsushima <span class="hlt">Warm</span> Current on circulation and water exchange processes in Tango Bay.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27612306','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27612306"><span id="translatedtitle"><span class="hlt">Warming</span> combined with more <span class="hlt">extreme</span> precipitation regimes modifies the water sources used by trees.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Grossiord, Charlotte; Sevanto, Sanna; Dawson, Todd E; Adams, Henry D; Collins, Adam D; Dickman, Lee T; Newman, Brent D; Stockton, Elizabeth A; McDowell, Nate G</p> <p>2017-01-01</p> <p>The persistence of vegetation under climate change will depend on a plant's capacity to exploit water resources. We analyzed water source dynamics in piñon pine and juniper trees subjected to precipitation reduction, atmospheric <span class="hlt">warming</span>, and to both simultaneously. Piñon and juniper exhibited different and opposite shifts in water uptake depth in response to experimental stress and background climate over 3 yr. During a dry summer, juniper responded to <span class="hlt">warming</span> with a shift to shallow water sources, whereas piñon pine responded to precipitation reduction with a shift to deeper sources in autumn. In normal and wet summers, both species responded to precipitation reduction, but juniper increased deep water uptake and piñon increased shallow water uptake. Shifts in the utilization of water sources were associated with reduced stomatal conductance and photosynthesis, suggesting that belowground compensation in response to <span class="hlt">warming</span> and water reduction did not alleviate stress impacts for gas exchange. We have demonstrated that predicted climate change could modify water sources of trees. <span class="hlt">Warming</span> impairs juniper uptake of deep sources during extended dry periods. Precipitation reduction alters the uptake of shallow sources following extended droughts for piñon. Shifts in water sources may not compensate for climate change impacts on tree physiology.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1325653','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1325653"><span id="translatedtitle"><span class="hlt">Warming</span> combined with more <span class="hlt">extreme</span> precipitation regimes modifies the water sources used by trees</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Grossiord, Charlotte; Sevanto, Sanna; Dawson, Todd E.; Adams, Henry D.; Collins, Adam D.; Dickman, Lee T.; Newman, Brent D.; Stockton, Elizabeth A.; McDowell, Nate G.</p> <p>2016-09-09</p> <p>The persistence of vegetation under climate change will depend on a plant's capacity to exploit water resources. In addition, we analyzed water source dynamics in piñon pine and juniper trees subjected to precipitation reduction, atmospheric <span class="hlt">warming</span>, and to both simultaneously.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70020047','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70020047"><span id="translatedtitle">Response of shoal grass, Halodule wrightii, to <span class="hlt">extreme</span> <span class="hlt">winter</span> conditions in the Lower Laguna Madre, Texas</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Hicks, D.W.; Onuf, C.P.; Tunnell, J.W.</p> <p>1998-01-01</p> <p>Effects of a severe freeze on the shoal grass, Halodule wrightii, were documented through analysis of temporal and spatial trends in below-ground biomass. The coincidence of the second lowest temperature (-10.6??C) in 107 years of record, 56 consecutive hours below freezing, high winds and <span class="hlt">extremely</span> low water levels exposed the Laguna Madre, TX, to the most severe cold stress in over a century. H. wrightii tolerated this <span class="hlt">extreme</span> freeze event. Annual pre- and post-freeze surveys indicated that below-ground biomass estimated from volume was Unaffected by the freeze event. Nor was there any post-freeze change in biomass among intertidal sites directly exposed to freezing air temperatures relative to subtidal sites which remained submerged during the freezing period.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27363163','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27363163"><span id="translatedtitle">[Effects of <span class="hlt">Warming</span> and Straw Application on Soil Respiration and Enzyme Activity in a <span class="hlt">Winter</span> Wheat Cropland].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chen, Shu-tao; Sang, Lin; Zhang, Xu; Hu, Zheng-hua</p> <p>2016-02-15</p> <p>In order to investigate the effects of <span class="hlt">warming</span> and straw application on soil respiration and enzyme activity, a field experiment was performed from November 2014 to May 2015. Four treatments, which were control (CK), <span class="hlt">warming</span>, straw application, and <span class="hlt">warming</span> and straw application, were arranged in field. Seasonal variability in soil respiration, soil temperature and soil moisture for different treatments were measured. Urease, invertase, and catalase activities for different treatments were measured at the elongation, booting, and anthesis stages. The results showed that soil respiration in different treatments had similar seasonal variation patterns. Seasonal mean soil respiration rates for the CK, <span class="hlt">warming</span>, straw application, and <span class="hlt">warming</span> and straw application treatments were 1.46, 1.96, 1.92, and 2.45 micromol x (m2 x s)(-1), respectively. ANOVA indicated that both <span class="hlt">warming</span> and straw applications significantly (P < 0.05) enhanced soil respiration compared to the control treatment. The relationship between soil respiration and soil temperature in different treatments fitted with the exponential regression function. The exponential regression functions explained 34.3%, 28.1%, 24.6%, and 32.0% variations of soil respiration for CK, <span class="hlt">warming</span>, straw application, and <span class="hlt">warming</span> and straw application treatments, respectively. <span class="hlt">Warming</span> and straw applications significantly (P < 0.05) enhanced urease, invertase, and catalase activities compared to CK. The relationship between soil respiration and urease activity fitted with a linear regression function, with the P value of 0.061. The relationship between soil respiration and invertase (P = 0.013), and between soil respiration and catalase activity (P = 0.002) fitted well with linear regression functions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JGRC..118..885Q','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JGRC..118..885Q"><span id="translatedtitle">Simulating the formation and fate of dense water in a midlatitude marginal sea during normal and <span class="hlt">warm</span> <span class="hlt">winter</span> conditions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Querin, Stefano; Cossarini, Gianpiero; Solidoro, Cosimo</p> <p>2013-02-01</p> <p>Dense shelf water production and the deep convection process in the Adriatic Sea are investigated, considering two case studies: the first is representative of the present climatic situation, whereas the second may be expected in a scenario characterized by mild <span class="hlt">winter</span> conditions over the basin. Dense water production and spreading are studied using a high-resolution implementation of the Massachusetts Institute of Technology general circulation model that is initialized and forced with realistic conditions. This paper provides qualitative and quantitative information on mass transport, dense water pathways, thermohaline structures, and the mixing properties of the basin. In the northern Adriatic shelf, seawater temperature is the key element for <span class="hlt">winter</span> dense water production because it contributes more relevantly than salinity in determining density. In the southern Adriatic Sea, a small amount of dense water that cascades directly into the pit can be formed on the narrow western shelf only during cold <span class="hlt">winter</span> conditions. Moreover, open ocean deepwater formation occurs in the middle of the southern basin. In late <span class="hlt">winter</span> and spring, although only when <span class="hlt">winter</span> conditions have been sufficiently cold, northern Adriatic dense shelf water forms a subsurface stream of which the densest part rapidly sinks in the southern pit along the shelf break, whereas its lighter part flows southward and reaches the Otranto Strait. The frequent occurrence of mild <span class="hlt">winter</span> conditions could lead to lower dense water production, with a reduced dense water flow from the Adriatic Sea to the Ionian Sea and a potential great impact on the eastern Mediterranean thermohaline circulation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012ClDy...38.1181Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012ClDy...38.1181Y"><span id="translatedtitle">Role of the ocean mixed layer processes in the response of the North Pacific <span class="hlt">winter</span> SST and MLD to global <span class="hlt">warming</span> in CGCMs</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yim, Bo Young; Noh, Yign; Yeh, Sang-Wook</p> <p>2012-03-01</p> <p>It is investigated how the changes of <span class="hlt">winter</span> sea surface temperature (SST) and mixed layer depth (MLD) under climate change projections are predicted differently in the North Pacific depending on the coupled general circulation models (CGCMs), and how they are related to the dynamical property of the simulated ocean mixed layer. For this purpose the dataset from eleven CGCMs reported to IPCC's AR4 are used, while detailed analysis is given to the MRI and MIROC models. Analysis of the CGCM data reveals that the increase of SST and the decrease of MLD in response to global <span class="hlt">warming</span> tend to be smaller for the CGCM in which the ratio of ocean heat transport (OHT) to surface heat flux (SHF), R (=|OHT/SHF|), is larger in the heat budget of the mixed layer. The negative correlation is found between the changes of OHT and SHF under global <span class="hlt">warming</span>, which may weaken the response to global <span class="hlt">warming</span> in the CGCM with larger R. It is also found that the models with low horizontal resolution tend to give broader western boundary currents, larger R, and the smaller changes of SST and MLD under global <span class="hlt">warming</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ClDy...48.1537D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ClDy...48.1537D"><span id="translatedtitle">Understanding the rapid summer <span class="hlt">warming</span> and changes in temperature <span class="hlt">extremes</span> since the mid-1990s over Western Europe</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dong, Buwen; Sutton, Rowan T.; Shaffrey, Len</p> <p>2017-03-01</p> <p>Analysis of observations indicates that there was a rapid increase in summer (June-August) mean surface air temperature (SAT) since the mid-1990s over Western Europe. Accompanying this rapid <span class="hlt">warming</span> are significant increases in summer mean daily maximum temperature, daily minimum temperature, annual hottest day temperature and warmest night temperature, and an increase in frequency of summer days and tropical nights, while the change in the diurnal temperature range (DTR) is small. This study focuses on understanding causes of the rapid summer <span class="hlt">warming</span> and associated temperature <span class="hlt">extreme</span> changes. A set of experiments using the atmospheric component of the state-of-the-art HadGEM3 global climate model have been carried out to quantify relative roles of changes in sea surface temperature (SST)/sea ice extent (SIE), anthropogenic greenhouse gases (GHGs), and anthropogenic aerosols (AAer). Results indicate that the model forced by changes in all forcings reproduces many of the observed changes since the mid-1990s over Western Europe. Changes in SST/SIE explain 62.2 ± 13.0 % of the area averaged seasonal mean <span class="hlt">warming</span> signal over Western Europe, with the remaining 37.8 ± 13.6 % of the <span class="hlt">warming</span> explained by the direct impact of changes in GHGs and AAer. Results further indicate that the direct impact of the reduction of AAer precursor emissions over Europe, mainly through aerosol-radiation interaction with additional contributions from aerosol-cloud interaction and coupled atmosphere-land surface feedbacks, is a key factor for increases in annual hottest day temperature and in frequency of summer days. It explains 45.5 ± 17.6 % and 40.9 ± 18.4 % of area averaged signals for these temperature <span class="hlt">extremes</span>. The direct impact of the reduction of AAer precursor emissions over Europe acts to increase DTR locally, but the change in DTR is countered by the direct impact of GHGs forcing. In the next few decades, greenhouse gas concentrations will continue to rise and AAer precursor</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/2016ClDy..tmp..220D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ClDy..tmp..220D"><span id="translatedtitle">Understanding the rapid summer <span class="hlt">warming</span> and changes in temperature <span class="hlt">extremes</span> since the mid-1990s over Western Europe</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dong, Buwen; Sutton, Rowan T.; Shaffrey, Len</p> <p>2016-05-01</p> <p>Analysis of observations indicates that there was a rapid increase in summer (June-August) mean surface air temperature (SAT) since the mid-1990s over Western Europe. Accompanying this rapid <span class="hlt">warming</span> are significant increases in summer mean daily maximum temperature, daily minimum temperature, annual hottest day temperature and warmest night temperature, and an increase in frequency of summer days and tropical nights, while the change in the diurnal temperature range (DTR) is small. This study focuses on understanding causes of the rapid summer <span class="hlt">warming</span> and associated temperature <span class="hlt">extreme</span> changes. A set of experiments using the atmospheric component of the state-of-the-art HadGEM3 global climate model have been carried out to quantify relative roles of changes in sea surface temperature (SST)/sea ice extent (SIE), anthropogenic greenhouse gases (GHGs), and anthropogenic aerosols (AAer). Results indicate that the model forced by changes in all forcings reproduces many of the observed changes since the mid-1990s over Western Europe. Changes in SST/SIE explain 62.2 ± 13.0 % of the area averaged seasonal mean <span class="hlt">warming</span> signal over Western Europe, with the remaining 37.8 ± 13.6 % of the <span class="hlt">warming</span> explained by the direct impact of changes in GHGs and AAer. Results further indicate that the direct impact of the reduction of AAer precursor emissions over Europe, mainly through aerosol-radiation interaction with additional contributions from aerosol-cloud interaction and coupled atmosphere-land surface feedbacks, is a key factor for increases in annual hottest day temperature and in frequency of summer days. It explains 45.5 ± 17.6 % and 40.9 ± 18.4 % of area averaged signals for these temperature <span class="hlt">extremes</span>. The direct impact of the reduction of AAer precursor emissions over Europe acts to increase DTR locally, but the change in DTR is countered by the direct impact of GHGs forcing. In the next few decades, greenhouse gas concentrations will continue to rise and AAer precursor</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.7931K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.7931K"><span id="translatedtitle">Changes in sub-daily precipitation <span class="hlt">extremes</span> in a global climate model with super-parameterization under CO2 <span class="hlt">warming</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Khairoutdinov, Marat; Zhou, Xin</p> <p>2015-04-01</p> <p>Virtually all of the projections for future change of <span class="hlt">extreme</span> precipitation statistics under CO2 <span class="hlt">warming</span> have been made using global climate models (GCMs) in which clouds and, in particular, convective cloud systems are not explicitly resolved, but rather parameterized. In our study, a different kind of a GCM, a super-parameterized Community Atmosphere Model (SP-CAM), is employed. In SP-CAM, all the conventional cloud parameterizations are replaced with a small-domain cloud resolving model (CRM), called super-parameterization (SP). The SP is embedded in each grid column of the host GCM. The resolution of each embedded CRM is 4 km, which is generally sufficient to explicitly represent deep convection, which is mostly responsible for <span class="hlt">extreme</span> precipitation events. In this study, we use the SP-CAM to contrast to the present and to conventional climate model, CAM, the sub-daily <span class="hlt">extreme</span> precipitation statistics in response to the sea-surface temperatures (SSTs) and CO2 levels as projected for the end of 21st century in response to the IPCC AR5 RCP8.5 emission scenario. Different mechanisms for <span class="hlt">extreme</span> precipitation changes are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010ems..confE.575P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010ems..confE.575P"><span id="translatedtitle">Madeira <span class="hlt">Extreme</span> Floods: 2009/2010 <span class="hlt">Winter</span>. Case study - 2nd and 20th of February</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pires, V.; Marques, J.; Silva, A.</p> <p>2010-09-01</p> <p>Floods are at world scale the natural disaster that affects a larger fraction of the population. It is a phenomenon that extends it's effects to the surrounding areas of the hydrographic network (basins, rivers, dams) and the coast line. Accordingly to USA FEMA (Federal Emergency Management Agency) flood can be defined as:"A general and temporary condition of partial or complete inundation of two or more acres of normally dry land area or of two or more properties from: Overflow of inland or tidal waters; Unusual and rapid accumulation or runoff of surface waters from any source; Mudflow; Collapse or subsidence of land along the shore of a lake or similar body of water as a result of erosion or undermining caused by waves or currents of water exceeding anticipated cyclical levels that result in a flood as defined above." A flash flood is the result of intense and long duration of continuous precipitation and can result in dead casualties (i.e. floods in mainland Portugal in 1967, 1983 and 1997). The speed and strength of the floods either localized or over large areas, results in enormous social impacts either by the loss of human lives and or the devastating damage to the landscape and human infrastructures. The <span class="hlt">winter</span> of 2009/2010 in Madeira Island was characterized by several episodes of very intense precipitation (specially in December 2009 and February 2010) adding to a new record of accumulated precipitation since there are records in the island. In February two days are especially rainy with absolute records for the month of February (daily records since 1949): 111mm and 97mm on the 2nd and 20th respectively. The accumulated precipitation ended up with the terrible floods on the 20th of February causing the lost of dozens of human lives and hundreds of millions of Euros of losses The large precipitation occurrences either more intense precipitation in a short period or less intense precipitation during a larger period are sometimes the precursor of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.H43E1539O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.H43E1539O"><span id="translatedtitle">Regional modeling sensitivity experiments for interpreting the UK <span class="hlt">Winter</span> 2013-2014 <span class="hlt">extreme</span> rain</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Omrani, H.; Vautard, R.; Schaller, N.; Allen, M. R.</p> <p>2015-12-01</p> <p>During the <span class="hlt">winter</span> 2013/2014, the UK saw heavy rainfalls associated with a succession of storms reaching Southern England causing widespread flooding, power cuts and major disruptions to transport. The January precipitation set a record for several rain gauge stations in Southern England. The aim of this study is to evaluate the contribution of the anthropogenic climate change, represented by a modification of the sea surface temperature (SST) on the January precipitation. For that, we conducted a sensitivity experiment by running a set of 108 four-months simulations using WRF model with 9 different physics and 12 different SST fields; 9 for the factual world and 99 for the counter-factual world. A spectral nudging technique was used here to ensure a same atmospheric circulation patterns for all the simulations. Therefore, only the thermodynamic effect is considered here. The analysis is focused on January precipitation over the southern England. Results show for 0,5°C SST difference over the Northern Atlantic, the precipitation in the factual simulations is between 0,4 and 8% higher than the precipitation in the counter-factual simulations depending on the physic. A validation test shows that this value is closer to 8% for the "best physic" simulation. It also show a strong spatial variability where in some region the precipitation is higher in the counter-factual world compared the factual world. Finally, a backward trajectories were calculated to evaluate the sensitivity of the moisture sources and air mass trajectories to the SST in the factual and the counter-factual world.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70032571','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70032571"><span id="translatedtitle">Design and quantification of an <span class="hlt">extreme</span> <span class="hlt">winter</span> storm scenario for emergency preparedness and planning exercises in California</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Dettinger, M.D.; Martin, Ralph F.; Hughes, M.; Das, T.; Neiman, P.; Cox, D.; Estes, G.; Reynolds, D.; Hartman, R.; Cayan, D.; Jones, L.</p> <p>2012-01-01</p> <p>The USGS Multihazards Project is working with numerous agencies to evaluate and plan for hazards and damages that could be caused by <span class="hlt">extreme</span> <span class="hlt">winter</span> storms impacting California. Atmospheric and hydrological aspects of a hypothetical storm scenario have been quantified as a basis for estimation of human, infrastructure, economic, and environmental impacts for emergency-preparedness and flood-planning exercises. In order to ensure scientific defensibility and necessary levels of detail in the scenario description, selected historical storm episodes were concatentated to describe a rapid arrival of several major storms over the state, yielding precipitation totals and runoff rates beyond those occurring during the individual historical storms. This concatenation allowed the scenario designers to avoid arbitrary scalings and is based on historical occasions from the 19th and 20th Centuries when storms have stalled over the state and when <span class="hlt">extreme</span> storms have arrived in rapid succession. Dynamically consistent, hourly precipitation, temperatures, barometric pressures (for consideration of storm surges and coastal erosion), and winds over California were developed for the so-called ARkStorm scenario by downscaling the concatenated global records of the historical storm sequences onto 6- and 2-km grids using a regional weather model of January 1969 and February 1986 storm conditions. The weather model outputs were then used to force a hydrologic model to simulate ARkStorm runoff, to better understand resulting flooding risks. Methods used to build this scenario can be applied to other emergency, nonemergency and non-California applications. ?? 2011 The Author(s).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16034411','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16034411"><span id="translatedtitle"><span class="hlt">Extreme</span> collisions between planetesimals as the origin of <span class="hlt">warm</span> dust around a Sun-like star.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Song, Inseok; Zuckerman, B; Weinberger, Alycia J; Becklin, E E</p> <p>2005-07-21</p> <p>The slow but persistent collisions between asteroids in our Solar System generate a tenuous cloud of dust known as the zodiacal light (because of the light the dust reflects). In the young Solar System, such collisions were more common and the dust production rate should have been many times larger. Yet copious dust in the zodiacal region around stars much younger than the Sun has rarely been found. Dust is known to orbit around several hundred main-sequence stars, but this dust is cold and comes from a Kuiper-belt analogous region out beyond the orbit of Neptune. Despite many searches, only a few main-sequence stars reveal <span class="hlt">warm</span> (> 120 K) dust analogous to zodiacal dust near the Earth. Signs of planet formation (in the form of collisions between bodies) in the regions of stars corresponding to the orbits of the terrestrial planets in our Solar System have therefore been elusive. Here we report an exceptionally large amount of <span class="hlt">warm</span>, small, silicate dust particles around the solar-type star BD+20,307 (HIP 8920, SAO 75016). The composition and quantity of dust could be explained by recent frequent or huge collisions between asteroids or other 'planetesimals' whose orbits are being perturbed by a nearby planet.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005Natur.436..363S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005Natur.436..363S"><span id="translatedtitle"><span class="hlt">Extreme</span> collisions between planetesimals as the origin of <span class="hlt">warm</span> dust around a Sun-like star</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Song, Inseok; Zuckerman, B.; Weinberger, Alycia J.; Becklin, E. E.</p> <p>2005-07-01</p> <p>The slow but persistent collisions between asteroids in our Solar System generate a tenuous cloud of dust known as the zodiacal light (because of the light the dust reflects). In the young Solar System, such collisions were more common and the dust production rate should have been many times larger. Yet copious dust in the zodiacal region around stars much younger than the Sun has rarely been found. Dust is known to orbit around several hundred main-sequence stars, but this dust is cold and comes from a Kuiper-belt analogous region out beyond the orbit of Neptune. Despite many searches, only a few main-sequence stars reveal <span class="hlt">warm</span> (> 120K) dust analogous to zodiacal dust near the Earth. Signs of planet formation (in the form of collisions between bodies) in the regions of stars corresponding to the orbits of the terrestrial planets in our Solar System have therefore been elusive. Here we report an exceptionally large amount of <span class="hlt">warm</span>, small, silicate dust particles around the solar-type star BD+20 307 (HIP8920, SAO75016). The composition and quantity of dust could be explained by recent frequent or huge collisions between asteroids or other `planetesimals' whose orbits are being perturbed by a nearby planet.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21088550','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21088550"><span id="translatedtitle">Effects of dynamic <span class="hlt">warm</span>-up with and without a weighted vest on lower <span class="hlt">extremity</span> power performance of high school male athletes.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Reiman, Michael P; Peintner, Ashley M; Boehner, Amber L; Cameron, Cori N; Murphy, Jessica R; Carter, John W</p> <p>2010-12-01</p> <p>This study examined lower <span class="hlt">extremity</span> power performance, using the Margaria-Kalamen Power Test, after a dynamic <span class="hlt">warm</span>-up with (resisted) and without (nonresisted) a weighted vest. Sixteen (n = 16) high school male football players, ages 14-18 years, participated in 2 randomly ordered testing sessions. One session involved performing the team's standard dynamic <span class="hlt">warm</span>-up while wearing a vest weighted at 5% of the individual athlete's body weight before performing 3 trials of the Margaria-Kalamen Power Test. The second session involved performing the same dynamic <span class="hlt">warm</span>-up without wearing a weighted vest before performing 3 trials of the Margaria-Kalamen Power Test. The <span class="hlt">warm</span>-up performed by the athletes consisted of various lower <span class="hlt">extremity</span> dynamic movements over a 5-minute period. No significant difference was found in power performance between the resisted and nonresisted dynamic <span class="hlt">warm</span>-up protocols (p > 0.05). The use of a dynamic <span class="hlt">warm</span>-up with a vest weighted at 5% of the athlete's body weight was not advantageous for increasing lower <span class="hlt">extremity</span> power output in this study. The results of this study suggest that resisted dynamic <span class="hlt">warm</span>-up protocols may not augment the production of power performance in high school football players.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.B43M..06B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.B43M..06B"><span id="translatedtitle">Deeper <span class="hlt">winter</span> snow reduces ecosystem C losses but increases the global <span class="hlt">warming</span> potential of Arctic tussock tundra over the growing season.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Blanc-Betes, E.; Welker, J. M.; Gomez-Casanovas, N.; Gonzalez-Meler, M. A.</p> <p>2015-12-01</p> <p>Arctic <span class="hlt">winter</span> precipitation is projected to increase globally over the next decades, spatial variability encompassing areas with increases and decreases in <span class="hlt">winter</span> snow. Changes in <span class="hlt">winter</span> precipitation strongly affect C dynamics in Arctic systems and may lead to major positive climate forcing feedbacks. However, impacts of predicted changes in snowfall and accumulation on the rate and form of C fluxes (CO2 and CH4) and associated forcing feedbacks from Arctic tundra remain uncertain. We investigated how changes in <span class="hlt">winter</span> precipitation affect net ecosystem CO2 and CH4 fluxes and budgets of moist acidic tundra in an 18-yrs snow fence experiment over a complete growing season at Toolik Lake, AK. Arctic tundra under ambient <span class="hlt">winter</span> precipitation (CTL) was a net source of CO2 and CH4, yielding net C losses over the growing season. Reduced snow (-15-30% snow depth; RS) switched the system to a net CO2 sink mostly by limiting SOC decomposition within colder soils. Snow additions progressively reduced net ecosystem CO2 losses compared to CTL, switching the system into a weaker net CO2 source with medium additions (+20-45% snow depth; MS) and into a small net CO2 sink with high additions (+70-100% snow depth; HS). Increasingly wetter soils with snow additions constrained the temperature sensitivity of aerobic decomposition and favored the anaerobic metabolism, buffering ecosystem CO2 losses despite substantial soil <span class="hlt">warming</span>. Accordingly, Arctic tundra switched from a sustained CH4 sink at RS site to an increasingly stronger CH4 source with snow additions. Accounting for both CO2 and CH4, the RS site became a net C sink over the growing season, overall reducing the global <span class="hlt">warming</span> potential (CO2 equiv.; GWP) of the system relative to CTL. Snow additions progressively reduced net C losses at the MS site compared to CTL and the system transitioned into a net C sink at HS plots, partly due to the slower metabolism of anaerobic decomposition. However, given the greater radiative</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70175033','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70175033"><span id="translatedtitle">Application of an <span class="hlt">extreme</span> <span class="hlt">winter</span> storm scenario to identify vulnerabilities, mitigation options, and science needs in the Sierra Nevada mountains, USA</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Albano, Christine M.; Dettinger, Michael; McCarthy, Maureen; Schaller, Kevin D.; Wellborn, Toby; Cox, Dale A.</p> <p>2016-01-01</p> <p>In the Sierra Nevada mountains (USA), and geographically similar areas across the globe where human development is expanding, <span class="hlt">extreme</span> <span class="hlt">winter</span> storm and flood risks are expected to increase with changing climate, heightening the need for communities to assess risks and better prepare for such events. In this case study, we demonstrate a novel approach to examining <span class="hlt">extreme</span> <span class="hlt">winter</span> storm and flood risks. We incorporated high-resolution atmospheric–hydrologic modeling of the ARkStorm <span class="hlt">extreme</span> <span class="hlt">winter</span> storm scenario with multiple modes of engagement with practitioners, including a series of facilitated discussions and a tabletop emergency management exercise, to develop a regional assessment of <span class="hlt">extreme</span> storm vulnerabilities, mitigation options, and science needs in the greater Lake Tahoe region of Northern Nevada and California, USA. Through this process, practitioners discussed issues of concern across all phases of the emergency management life cycle, including preparation, response, recovery, and mitigation. Interruption of transportation, communications, and interagency coordination were among the most pressing concerns, and specific approaches for addressing these issues were identified, including prepositioning resources, diversifying communications systems, and improving coordination among state, tribal, and public utility practitioners. Science needs included expanding real-time monitoring capabilities to improve the precision of meteorological models and enhance situational awareness, assessing vulnerabilities of critical infrastructure, and conducting cost–benefit analyses to assess opportunities to improve both natural and human-made infrastructure to better withstand <span class="hlt">extreme</span> storms. Our approach and results can be used to support both land use and emergency planning activities aimed toward increasing community resilience to <span class="hlt">extreme</span> <span class="hlt">winter</span> storm hazards in mountainous regions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1815290L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1815290L"><span id="translatedtitle"><span class="hlt">Extreme</span> coastal storms along the north coast of Ireland: hydrodynamic forcing and beach response during the <span class="hlt">winter</span> seasons of 2013/14 and 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>Loureiro, Carlos; Marianne, O'Connor; Guisado-Pintado, Emilia; Jackson, Derek; Cooper, Andrew</p> <p>2016-04-01</p> <p>The increase in storminess (frequency, duration and magnitude) and the occurrence of <span class="hlt">extreme</span> coastal storms partly associated with climate change, represent pressing concerns for coastal communities in many regions globally. The Atlantic seaboard of Europe has recently experienced record-breaking <span class="hlt">winter</span> seasons, particularly in Ireland and the UK, where the 2013/14 <span class="hlt">winter</span> was characterised as the stormiest on record according to measured levels of total precipitation, <span class="hlt">extreme</span> wind speeds, and particularly the frequency and intensity of cyclone activity. The enhanced cyclone activity during 2013/14 has resulted in unprecedented sequences of <span class="hlt">extreme</span> water levels and energetic waves and gave rise to widespread coastal erosion and flooding, setting new benchmarks for coastal analysis and offered a glimpse of future storm impact scenarios. A regional analysis of hydrodynamic forcing along the north coast of Ireland over the last two extended <span class="hlt">winter</span> seasons (October to March) has revealed that, although 2013/14 was indeed characterised by an exceptional frequency and intensity of coastal storms, the 2014/15 extended <span class="hlt">winter</span> was significantly stormier. Not only was the number of individual storm events higher, but also the duration and intensity was greater, including record values of offshore significant wave height. The geomorphic response along the sandy coastal stretches of the north coast of Ireland, evaluated from morphological change at a diverse group of beach sites, revealed considerable differences in beach erosion and actual shoreline response. Variability in beach changes during these two <span class="hlt">extreme</span> <span class="hlt">winter</span> seasons is attributed to a variety of factors. These include localised coastal orientation relative to particular storm tracks, the embayed and highly compartmentalised setting of most of the beaches, as well as site-specific morphodynamic mechanisms such as large rip-current cells forcing the onset and/or reactivation of erosional hotspots. Such heterogeneous</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.3623W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.3623W"><span id="translatedtitle">Changing precipitation <span class="hlt">extremes</span> in a <span class="hlt">warming</span> climate: A basis for design flood estimation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wasko, Conrad; Sharma, Ashish</p> <p>2016-04-01</p> <p>The potential for increasing intensity of future rainfall events has significant implications for flooding and the design of infrastructure. However the questions of how precipitation will change in the future, how important these changes are to flooding, and how engineers incorporate these changes into hydrologic design remain as open questions. In the absence of reliable point based estimates of how precipitation will change, many studies investigate the historical relationship between rainfall intensity and temperature as a proxy for what may happen in a warmer climate. Much of the research to date has focussed on changing precipitation intensity, however, temporal and spatial patterns of precipitation are just as important. Here we link higher temperatures to changes in temporal and spatial patterns of <span class="hlt">extreme</span> precipitation events. We show, using observed high quality precipitation records from Australia covering all major climatic zones, that storms are intensifying in both time and space resulting in a greater potential for flooding especially in urban locales around the world. Given that precipitation and antecedent conditions are changing, and, the impacts to flooding are significant, methods of incorporating these changes in catchment modelling are required. Continuous simulation offers a natural flexibility to incorporate the many correlated changes in precipitation that may occur in a future climate. An argument for such a framework using existing continuous simulation alternatives is articulated in concluding this presentation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.7482K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.7482K"><span id="translatedtitle">Investigation of the structure and stability of the lower atmosphere by microwave ground-based sensing over Nizhniy Novgorod, Russia during abnormally <span class="hlt">warm</span> <span class="hlt">winter</span> 2013 - 2014</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Karashtin, Dmitriy; Berezin, Evgeny; Kulikov, Mikhail; Feigin, Alexander</p> <p>2014-05-01</p> <p>The monitoring of the lower atmosphere structure and stability is required for studying the processes of the convection in the atmosphere, determining the mutual influence of global climate change trends and the current state of regional climate systems, which have an impact on the appearance of dangerous meteorological events (heavy rains, thunderstorms, hail, floods, squalls, tornadoes, etc). There are many methods of measuring structure of the atmosphere: contact (rocket and balloon), contactless - active (lidar) and passive (radiometric), with the placement of the instrumentation on the satellite, airplanes and the Earth's surface (ground-based). For the convection processes study in order to predict dangerous meteorological events the ground-based radiometric sensing of the structure of the lower atmosphere seems to be the most suitable due to higher time and spatial resolution. This report discusses the peculiarities of the structure of the lower atmosphere over Nizhniy Novgorod, Russia during the abnormally <span class="hlt">warm</span> <span class="hlt">winter</span> 2013 - 2014 retrieved from measurements by radiometric complex HATPRO-G3 by Radiometer Physics GmbH. This complex gives vertical thermal and water vapor profiles of the lower atmosphere (0 - 10 km) with time resolution of a few minutes, horizontally resolution of about 10 kilometers and vertically resolution of about 100 meters. The analysis of the structure and stability of the lower atmosphere is based on the vertical distribution of virtual potential temperature derived from these measurements under the hydrostatic approximation. Also the comparison of the results for the abnormally <span class="hlt">winter</span> 2013 - 2014 and the data computed from the Weather Research and Forecasting (WRF) Model (http://www.wrf-model.org) for <span class="hlt">winter</span> 2011 - 2012 is discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/publication/?seqNo115=282970','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/publication/?seqNo115=282970"><span id="translatedtitle">The <span class="hlt">warm</span> <span class="hlt">winter</span> and spring of 2012: Why degree-days were critical in measuring insect and plant development</span></a></p> <p><a target="_blank" href="http://www.ars.usda.gov/services/TekTran.htm">Technology Transfer Automated Retrieval System (TEKTRAN)</a></p> <p></p> <p></p> <p>In the spring of 2012, <span class="hlt">extremely</span> high temperatures were recorded in the upper Midwest during the month of March. This sustained heat wave not only made March the warmest on record, but also induced remarkably fast development of arthropods and plants. In terms of degree-days, however, the arthropod ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1991GeoRL..18.1987C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1991GeoRL..18.1987C"><span id="translatedtitle">Strato-meso-thermospheric coupling at mid-latitudes in the course of mid-<span class="hlt">winter</span> strat-<span class="hlt">warmings</span> during Dyana</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cevolani, Giordano</p> <p>1991-11-01</p> <p>Wind observations in the meteor region carried out at the CNR radar station near Bologna (45°N 12°E) in the <span class="hlt">winter</span> of 1989-90 during the DYANA (DYnamics Adapted Network for the Atmosphere) project, give evidence of significant strato-meso-thermospheric coupling in the course of two strat-<span class="hlt">warmings</span> recorded at the end of January and in mid-February 1990. Amplification of 10-12 day long-period waves just a few days before the temperature peak at the 10 hPa stratospheric level, and the strong phase variations of the semidiurnal tide (ST) in the 80-110 km region during the two separate events could be of interest for our knowledge of the evolution and influence of a strat-<span class="hlt">warming</span> in the overall middle atmosphere. Possible interference processes and nonlinear mixing between planetary waves with different periodicities could account not only for aspects of wave amplification but also for the presence of subsidiary peaks of long period waves in the amplitude spectra of the observed zonal winds.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016R%26QE...59..270B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016R%26QE...59..270B"><span id="translatedtitle">Ground-Based Microwave Monitoring of Middle-Atmosphere Ozone Above Peterhof and Tomsk During Stratospheric <span class="hlt">Warming</span> in the <span class="hlt">Winter</span> of 2013-2014</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bochkovsky, D. A.; Virolainen, Ya. A.; Kulikov, Yu. Yu.; Marichev, V. N.; Poberovsky, A. V.; Ryskin, V. G.; Timofeyev, Yu. M.</p> <p>2016-09-01</p> <p>We present the results of studying the dynamics of middle-atmosphere ozone above Peterhof (60°N, 30°E) and Tomsk (56°N, 85°E) during stratospheric <span class="hlt">warming</span> in the <span class="hlt">winter</span> of 2013-2014 by the radiophysical method. In the ground-based observations we used the same microwave ozone meters (operated at 110.8 GHz) and the same techniques both for measuring the radiation spectra of ozone molecules and estimation of the vertical distribution of ozone in the middle atmosphere. These results were compared with satellite data on the total ozone content TOC (OMI/Aura), altitude profiles of ozone and temperature in the layer 20-60 km (MLS/Aura), and also with the data on ozone content in the layer 25-60 km, which were obtained using a Bruker IFS-125HR infrared Fourier spectrometer in Peterhof. Significant variations in ozone, which were caused by a stratospheric <span class="hlt">warming</span> of the minor type, were observed in the atmosphere above Peterhof at altitudes of 40 to 60 km. The duration of dynamic perturbations above Peterhof was 2.5 months. Dynamic processes associated with the horizontal transport of air masses, which had an impact on the vertical structure of ozone in the middle atmosphere, were also detected above Tomsk, but this effect was less dependent on the background temperature variations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMGC42A..06S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMGC42A..06S"><span id="translatedtitle">Impact of Anthropogenic Land Cover Change on <span class="hlt">Warm</span> Temperature <span class="hlt">Extremes</span> : the summer 2003 heat waves as a testbed</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Stéfanon, M.</p> <p>2013-12-01</p> <p>Events similar to the 2003 mega heat wave will be likely more frequent, intense and longer by the end of the 21st century owing to enhanced atmospheric greenhouse-gas concentrations. Policies for climate mitigation privileges carbon sequestration techniques while land cover change (LCC) may be a preferred alternative in terms of environmental impact, where geography permits. Biogeophysical factors such as albedo, evapotranspiration, and surface roughness may have locally the potential to offset the biogeochemical impact of increased greenhouse-gas. However, so far the set of existing (but not consistent) LCC impact studies conducted in the Mediterranean have contradictory results on summer temperature (cooling or <span class="hlt">warming</span>). Using the Model of the Regional Coupled Earth system (MORCE), the impact of an afforestation scenario (POT) is conducted for both 2002 and 2003 years, and compared to an agricultural scenario (CUR). The favorable meteorological conditions in spring 2003 fasten the development of agricultural vegetation in CUR compared to a) conditions in 2002, and b) to the development of trees in POT. This greater photosynthetic capacity of crops, followed by larger evapotranspiration rates, dampens the <span class="hlt">extreme</span> values of temperature from April to the end of June 2003 (locally by 3°C) and more specifically during the June heat-wave (locally by 1.6°C). It contributes to increase the differences between POT and CUR in 2003 compared to 2002. In July vegetation starts to get limited by soil moisture, and agricultural plants are most affected than trees because of their shallower roots. From early July to October, trees are not too water limited. They can still evaporate, while water stress in CUR makes croplands contribute to enhance the <span class="hlt">warm</span> summer temperatures, especially in 2003. The very hot summer 2003 July-August temperatures are therefore amplified (resp. dampened) by the presence of crops (resp. trees) in CUR (resp. POT). However this cooling capacity of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016IJBm...60.1885C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016IJBm...60.1885C"><span id="translatedtitle">Recent <span class="hlt">warming</span> evidence inferred from a tree-ring-based <span class="hlt">winter</span>-half year minimum temperature reconstruction in northwestern Yichang, South Central China, and its relation to the large-scale circulation anomalies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cai, Qiufang; Liu, Yu; Wang, Yanchao; Ma, Yongyong; Liu, Han</p> <p>2016-12-01</p> <p>High-resolution <span class="hlt">winter</span> temperature reconstructions in China are rare, yet vital for the comprehensive understanding of past climate change. In the present work, the first <span class="hlt">winter</span>-half year minimum mean temperature from previous November to current April in northwestern Yichang, South Central China, was reconstructed back to 1875 based on tree-ring material. The reconstruction can explain 55 % of the variance over the calibration period during 1955-2011. The temperature maintained at comparatively low level before 1958, and an abnormal <span class="hlt">warming</span> was seen since 1959. However, the <span class="hlt">warming</span> trend stagnated after 2000 AD. 2001-2010 was the warmest decade not only during the instrumental period but also during the whole reconstructed period. The reconstruction indicates good spatial resemblance to other temperatures series in adjacent areas and Northern Hemisphere, yet the recent <span class="hlt">warming</span> in this study is earlier and more prominent than that of Southeast China. This work also manifests that the <span class="hlt">winter</span>-half year minimum temperature in study area has good agreement with summer (June-September) maximum temperature variation in Southeast China at decadal scale, except that the <span class="hlt">winter</span>-half year <span class="hlt">warming</span> in recent decades is more evident than summer. This reconstruction is not only useful in improving our knowledge of long-term temperature variation but also useful in predicting the tree growth dynamics in the future in the study area.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1815087L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1815087L"><span id="translatedtitle">Contribution of the land-use forcing to the increase in risk of <span class="hlt">warm</span> <span class="hlt">extreme</span> events since 1850 over North America from constrained CMIP5 simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lejeune, Quentin; Davin, Edouard; Seneviratne, Sonia</p> <p>2016-04-01</p> <p>During the industrial period, large areas of North America experienced a reduction in forest cover and an expansion of agricultural areas. There is indication that this has affected the intensity and frequency of temperature <span class="hlt">extremes</span> through changes in biophysical land surface properties (Christidis et al., 2013, Pitman et al., 2012). However, it has never been addressed in the context of a multi-model transient experiment ensemble. Here we intend to constrain CMIP5 models with observations in order to assess the contribution of historical land-cover changes (LCC) to changes in the risk of <span class="hlt">warm</span> <span class="hlt">extreme</span> events over North America. We have retained only six models from the CMIP5 ensemble that can reproduce the local <span class="hlt">warming</span> effect of deforestation during daytime, which was identified in present-day observations of the impact of deforestation on mean summer temperature (Lee et al, 2011). As for its observed cooling effect during nighttime, we kept the sole model that is able to simulate it. Using a framework derived from the Fraction of Attributable Risk methodology, we have then quantified by how much the increase in risk of getting a particular <span class="hlt">extreme</span> event driven by increased greenhouse gas concentrations (GHG) was damped or amplified over areas which were largely affected by LCC, compared to surrounding ones that experienced few LCC over the same period. We find that the constrained model ensemble indicates an amplification by between 10 and more than 100% by local LCC of the increase in risk of occurrence of a <span class="hlt">warm</span> <span class="hlt">extreme</span> event corresponding to the 90th percentile during the pre-industrial period, depending on the model. This amplification factor gets higher for more <span class="hlt">extreme</span> events, rising to at least 20% for the 995th permille. Regarding nighttime temperatures, the retained model indicates that historical LCC have locally more than cancelled the effect of increased GHG concentrations on the frequency of <span class="hlt">warm</span> <span class="hlt">extreme</span> events corresponding to between the 90th</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1039923','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1039923"><span id="translatedtitle">Response of precipitation <span class="hlt">extremes</span> to idealized global <span class="hlt">warming</span> in an aqua-planet climate model: Towards robust projection across different horizontal resolutions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Li, F.; Collins, W.D.; Wehner, M.F.; Williamson, D.L.; Olson, J.G.</p> <p>2011-04-15</p> <p>Current climate models produce quite heterogeneous projections for the responses of precipitation <span class="hlt">extremes</span> to future climate change. To help understand the range of projections from multimodel ensembles, a series of idealized 'aquaplanet' Atmospheric General Circulation Model (AGCM) runs have been performed with the Community Atmosphere Model CAM3. These runs have been analysed to identify the effects of horizontal resolution on precipitation <span class="hlt">extreme</span> projections under two simple global <span class="hlt">warming</span> scenarios. We adopt the aquaplanet framework for our simulations to remove any sensitivity to the spatial resolution of external inputs and to focus on the roles of model physics and dynamics. Results show that a uniform increase of sea surface temperature (SST) and an increase of low-to-high latitude SST gradient both lead to increase of precipitation and precipitation <span class="hlt">extremes</span> for most latitudes. The perturbed SSTs generally have stronger impacts on precipitation <span class="hlt">extremes</span> than on mean precipitation. Horizontal model resolution strongly affects the global <span class="hlt">warming</span> signals in the <span class="hlt">extreme</span> precipitation in tropical and subtropical regions but not in high latitude regions. This study illustrates that the effects of horizontal resolution have to be taken into account to develop more robust projections of precipitation <span class="hlt">extremes</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_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('https://www.ncbi.nlm.nih.gov/pubmed/27604976','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27604976"><span id="translatedtitle">Record-breaking <span class="hlt">warming</span> and <span class="hlt">extreme</span> drought in the Amazon rainforest during the course of El Niño 2015-2016.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Jiménez-Muñoz, Juan C; Mattar, Cristian; Barichivich, Jonathan; Santamaría-Artigas, Andrés; Takahashi, Ken; Malhi, Yadvinder; Sobrino, José A; Schrier, Gerard van der</p> <p>2016-09-08</p> <p>The El Niño-Southern Oscillation (ENSO) is the main driver of interannual climate <span class="hlt">extremes</span> in Amazonia and other tropical regions. The current 2015/2016 EN event was expected to be as strong as the EN of the century in 1997/98, with <span class="hlt">extreme</span> heat and drought over most of Amazonian rainforests. Here we show that this protracted EN event, combined with the regional <span class="hlt">warming</span> trend, was associated with unprecedented <span class="hlt">warming</span> and a larger extent of <span class="hlt">extreme</span> drought in Amazonia compared to the earlier strong EN events in 1982/83 and 1997/98. Typical EN-like drought conditions were observed only in eastern Amazonia, whilst in western Amazonia there was an unusual wetting. We attribute this wet-dry dipole to the location of the maximum sea surface <span class="hlt">warming</span> on the Central equatorial Pacific. The impacts of this climate <span class="hlt">extreme</span> on the rainforest ecosystems remain to be documented and are likely to be different to previous strong EN events.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatSR...633130J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatSR...633130J"><span id="translatedtitle">Record-breaking <span class="hlt">warming</span> and <span class="hlt">extreme</span> drought in the Amazon rainforest during the course of El Niño 2015–2016</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jiménez-Muñoz, Juan C.; Mattar, Cristian; Barichivich, Jonathan; Santamaría-Artigas, Andrés; Takahashi, Ken; Malhi, Yadvinder; Sobrino, José A.; Schrier, Gerard Van Der</p> <p>2016-09-01</p> <p>The El Niño-Southern Oscillation (ENSO) is the main driver of interannual climate <span class="hlt">extremes</span> in Amazonia and other tropical regions. The current 2015/2016 EN event was expected to be as strong as the EN of the century in 1997/98, with <span class="hlt">extreme</span> heat and drought over most of Amazonian rainforests. Here we show that this protracted EN event, combined with the regional <span class="hlt">warming</span> trend, was associated with unprecedented <span class="hlt">warming</span> and a larger extent of <span class="hlt">extreme</span> drought in Amazonia compared to the earlier strong EN events in 1982/83 and 1997/98. Typical EN-like drought conditions were observed only in eastern Amazonia, whilst in western Amazonia there was an unusual wetting. We attribute this wet-dry dipole to the location of the maximum sea surface <span class="hlt">warming</span> on the Central equatorial Pacific. The impacts of this climate <span class="hlt">extreme</span> on the rainforest ecosystems remain to be documented and are likely to be different to previous strong EN events.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5015046','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5015046"><span id="translatedtitle">Record-breaking <span class="hlt">warming</span> and <span class="hlt">extreme</span> drought in the Amazon rainforest during the course of El Niño 2015–2016</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Jiménez-Muñoz, Juan C.; Mattar, Cristian; Barichivich, Jonathan; Santamaría-Artigas, Andrés; Takahashi, Ken; Malhi, Yadvinder; Sobrino, José A.; Schrier, Gerard van der</p> <p>2016-01-01</p> <p>The El Niño-Southern Oscillation (ENSO) is the main driver of interannual climate <span class="hlt">extremes</span> in Amazonia and other tropical regions. The current 2015/2016 EN event was expected to be as strong as the EN of the century in 1997/98, with <span class="hlt">extreme</span> heat and drought over most of Amazonian rainforests. Here we show that this protracted EN event, combined with the regional <span class="hlt">warming</span> trend, was associated with unprecedented <span class="hlt">warming</span> and a larger extent of <span class="hlt">extreme</span> drought in Amazonia compared to the earlier strong EN events in 1982/83 and 1997/98. Typical EN-like drought conditions were observed only in eastern Amazonia, whilst in western Amazonia there was an unusual wetting. We attribute this wet-dry dipole to the location of the maximum sea surface <span class="hlt">warming</span> on the Central equatorial Pacific. The impacts of this climate <span class="hlt">extreme</span> on the rainforest ecosystems remain to be documented and are likely to be different to previous strong EN events. PMID:27604976</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009EGUGA..11.5554W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009EGUGA..11.5554W"><span id="translatedtitle">20th century global <span class="hlt">warming</span> favoured enhanced intensity of <span class="hlt">extreme</span> torrential events - a proglacial sediment record in NW French Alps</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wilhelm, B.; Arnaud, F.; Legaz, A.; Allignol, F.; Enters, D.; Revillon, S.</p> <p>2009-04-01</p> <p>During the past few yeas, considerable climate changes have been observed at high elevation areas of the European Alps. Additionally, one of the main results of high resolution climate modelling is a trend towards both dryer summer conditions and enhanced risk of <span class="hlt">extreme</span> floods. This should have particularly dramatic consequences in alpine areas. Indeed, the development of tourism during the 20th century in the Alps and the rise of population density resulted in an increasing potential risk from natural hazards. Among them, torrential floods are some of the most common and widespread ones. They cause both loss of human life and high damage to property and infrastructure and are particularly destructive in mountain areas. For example, in August 2005, an unusual meteorological situation resulted in a series of catastrophic floods in most regions of the European Alps and particularly in the catchment of the Vorz river, downstream of proglacial Lac Blanc (2170 m a.s.l., Belledonne range, NW French Alps). We studied a series of sediment cores from Lac Blanc, spanning the last ca. 250 years. Through a coupled high resolution sedimentological and geochemical approach we documented about 100 flood deposits and measured their thickness. The age of each deposit has been assessed by radiochemical dating and the recognition of historically-known events - major earthquakes and historical atmospheric lead deposition. Furthermore, a detailed study of regional and local historical archives was conducted allowing us to relate the recognised flood deposits to the ones reported by local population. We hence obtained a flood calendar from 1740 to 2005 with the respective intensity of each event assessed by the thickness of the associated deposit. The flood frequency shows an important and punctual increase at the early end of the Little Ice Age (1830 - 1860) as a response to the beginning <span class="hlt">warming</span> period, which was emphasized by the synchronous local glacier retreat. On the other hand</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.2394P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.2394P"><span id="translatedtitle">Quantitative and qualitative responses of soil organic carbon to six years of <span class="hlt">extreme</span> soil <span class="hlt">warming</span> in a subarctic grassland in Iceland</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Poeplau, Christopher; Leblans, Niki I. W.; Sigurdsson, Bjarni D.; Kätterer, Thomas</p> <p>2016-04-01</p> <p>Terrestrial carbon cycle feedbacks to global <span class="hlt">warming</span> are expected, but constitute a major uncertainty in climate models. Soils in northern latitudes store a large proportion of the total global biosphere carbon stock and might thus become a strong source of CO2 when <span class="hlt">warmed</span>. Long-term in situ observations of <span class="hlt">warming</span> effects on soil organic carbon (SOC) dynamics are indispensable for an in depth understanding of the involved processes. We investigated the effect of six years of soil <span class="hlt">warming</span> on SOC quantity and quality in a geothermally heated grassland soil in Iceland. We isolated five fractions of SOC along an <span class="hlt">extreme</span> soil <span class="hlt">warming</span> gradient of +0 to +40°C. Those fractions vary conceptually in turnover time from active to passive in the following order: particulate organic matter (POM), dissolved organic carbon (DOC), SOC in sand and stable aggregates (SA), SOC in silt and clay (SC-rSOC) and resistant SOC (rSOC). Soil <span class="hlt">warming</span> of 1°C increased bulk SOC by 22% (0-10 cm) and 27% (20-30 cm), while further <span class="hlt">warming</span> led to exponential SOC depletion of up to 79% (0-10 cm) and 74% (20-30) in the most heated plots (~ +40°C). Only the SA fraction was more sensitive than the bulk soil, with 93% (0-10 cm) and 86% (20-30 cm) losses and with the highest relative enrichment in 13C (+1.6‰ in 0-10 cm and +1.3‰ in 20-30 cm). In addition, the mass of the SA fraction did significantly decline along the <span class="hlt">warming</span> gradient, which we explained by devitalization of aggregate binding mechanisms. As a consequence, the fine SC fraction mass increased with <span class="hlt">warming</span> which explained the relative enrichment of presumably more slow-cycling SOC (R2=0.61 in 0-10 cm and R2=0.92 in 20-30 cm). Unexpectedly, no difference was observed between the responses of SC-rSOC (slow-cycling) and rSOC (passive) to <span class="hlt">warming</span>. Furthermore, the 13C enrichment by trophic fractionation in the passive rSOC fraction was equal to this in the bulk soil. We therefore conclude that the sensitivity of SOC to <span class="hlt">warming</span> was not a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21839679','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21839679"><span id="translatedtitle">Sphagnum-dwelling testate amoebae in subarctic bogs are more sensitive to soil <span class="hlt">warming</span> in the growing season than in <span class="hlt">winter</span>: the results of eight-year field climate manipulations.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Tsyganov, Andrey N; Aerts, Rien; Nijs, Ivan; Cornelissen, Johannes H C; Beyens, Louis</p> <p>2012-05-01</p> <p>Sphagnum-dwelling testate amoebae are widely used in paleoclimate reconstructions as a proxy for climate-induced changes in bogs. However, the sensitivity of proxies to seasonal climate components is an important issue when interpreting proxy records. Here, we studied the effects of summer <span class="hlt">warming</span>, <span class="hlt">winter</span> snow addition solely and <span class="hlt">winter</span> snow addition together with spring <span class="hlt">warming</span> on testate amoeba assemblages after eight years of experimental field climate manipulations. All manipulations were accomplished using open top chambers in a dry blanket bog located in the sub-Arctic (Abisko, Sweden). We estimated sensitivity of abundance, diversity and assemblage structure of living and empty shell assemblages of testate amoebae in the living and decaying layers of Sphagnum. Our results show that, in a sub-arctic climate, testate amoebae are more sensitive to climate changes in the growing season than in <span class="hlt">winter</span>. Summer <span class="hlt">warming</span> reduced species richness and shifted assemblage composition towards predominance of xerophilous species for the living and empty shell assemblages in both layers. The higher soil temperatures during the growing season also decreased abundance of empty shells in both layers hinting at a possible increase in their decomposition rates. Thus, although possible effects of climate changes on preservation of empty shells should always be taken into account, species diversity and structure of testate amoeba assemblages in dry subarctic bogs are sensitive proxies for climatic changes during the growing season.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4839561','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4839561"><span id="translatedtitle">Grain Yield and Water Use Efficiency in <span class="hlt">Extremely</span>-Late Sown <span class="hlt">Winter</span> Wheat Cultivars under Two Irrigation Regimes in the North China Plain</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Wang, Bin; Zhang, Yinghua; Hao, Baozhen; Xu, Xuexin; Zhao, Zhigan; Wang, Zhimin; Xue, Qingwu</p> <p>2016-01-01</p> <p>Wheat production is threatened by water shortages and groundwater over-draft in the North China Plain (NCP). In recent years, <span class="hlt">winter</span> wheat has been increasingly sown <span class="hlt">extremely</span> late in early to mid-November after harvesting cotton or pepper. To improve water use efficiency (WUE) and guide the <span class="hlt">extremely</span> late sowing practices, a 3-year field experiment was conducted under two irrigation regimes (W1, one-irrigation, 75 mm at jointing; W2, two-irrigation, 75 mm at jointing and 75 mm at anthesis) in 3 cultivars differing in spike size (HS4399, small spike; JM22, medium spike; WM8, large spike). Wheat was sown in early to mid-November at a high seeding rate of 800–850 seeds m−2. Average yields of 7.42 t ha−1 and WUE of 1.84 kg m−3 were achieved with an average seasonal evapotranspiration (ET) of 404 mm. Compared with W2, wheat under W1 did not have yield penalty in 2 of 3 years, and had 7.9% lower seasonal ET and 7.5% higher WUE. The higher WUE and stable yield under W1 was associated with higher 1000-grain weight (TGW) and harvest index (HI). Among the 3 cultivars, JM22 had 5.9%–8.9% higher yield and 4.2%–9.3% higher WUE than WM8 and HS4399. The higher yield in JM22 was attributed mainly to higher HI and TGW due to increased post-anthesis biomass and deeper seasonal soil water extraction. In conclusion, one-irrigation with a medium-sized spike cultivar JM22 could be a useful strategy to maintain yield and high WUE in <span class="hlt">extremely</span> late-sown <span class="hlt">winter</span> wheat at a high seeding rate in the NCP. PMID:27100187</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27100187','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27100187"><span id="translatedtitle">Grain Yield and Water Use Efficiency in <span class="hlt">Extremely</span>-Late Sown <span class="hlt">Winter</span> Wheat Cultivars under Two Irrigation Regimes in the North China Plain.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wang, Bin; Zhang, Yinghua; Hao, Baozhen; Xu, Xuexin; Zhao, Zhigan; Wang, Zhimin; Xue, Qingwu</p> <p>2016-01-01</p> <p>Wheat production is threatened by water shortages and groundwater over-draft in the North China Plain (NCP). In recent years, <span class="hlt">winter</span> wheat has been increasingly sown <span class="hlt">extremely</span> late in early to mid-November after harvesting cotton or pepper. To improve water use efficiency (WUE) and guide the <span class="hlt">extremely</span> late sowing practices, a 3-year field experiment was conducted under two irrigation regimes (W1, one-irrigation, 75 mm at jointing; W2, two-irrigation, 75 mm at jointing and 75 mm at anthesis) in 3 cultivars differing in spike size (HS4399, small spike; JM22, medium spike; WM8, large spike). Wheat was sown in early to mid-November at a high seeding rate of 800-850 seeds m(-2). Average yields of 7.42 t ha(-1) and WUE of 1.84 kg m(-3) were achieved with an average seasonal evapotranspiration (ET) of 404 mm. Compared with W2, wheat under W1 did not have yield penalty in 2 of 3 years, and had 7.9% lower seasonal ET and 7.5% higher WUE. The higher WUE and stable yield under W1 was associated with higher 1000-grain weight (TGW) and harvest index (HI). Among the 3 cultivars, JM22 had 5.9%-8.9% higher yield and 4.2%-9.3% higher WUE than WM8 and HS4399. The higher yield in JM22 was attributed mainly to higher HI and TGW due to increased post-anthesis biomass and deeper seasonal soil water extraction. In conclusion, one-irrigation with a medium-sized spike cultivar JM22 could be a useful strategy to maintain yield and high WUE in <span class="hlt">extremely</span> late-sown <span class="hlt">winter</span> wheat at a high seeding rate in the NCP.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4648455','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4648455"><span id="translatedtitle"><span class="hlt">Extreme</span> defoliation reduces tree growth but not C and N storage in a <span class="hlt">winter</span>-deciduous 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>Piper, Frida I.; Gundale, Michael J.; Fajardo, Alex</p> <p>2015-01-01</p> <p>Background and Aims There is a growing concern about how forests will respond to increased herbivory associated with climate change. Carbon (C) and nitrogen (N) limitation are hypothesized to cause decreasing growth after defoliation, and eventually mortality. This study examines the effects of a natural and massive defoliation by an insect on mature trees’ C and N storage, which have rarely been studied together, particularly in <span class="hlt">winter</span>-deciduous species. Methods Survival, growth rate, carbon [C, as non-structural carbohydrate (NSC) concentration] and nitrogen (N) storage, defences (tannins and total polyphenols), and re-foliation traits were examined in naturally defoliated and non-defoliated adult trees of the <span class="hlt">winter</span>-deciduous temperate species Nothofagus pumilio 1 and 2 years after a massive and complete defoliation caused by the caterpillar of Ormiscodes amphimone (Saturniidae) during summer 2009 in Patagonia. Key Results Defoliated trees did not die but grew significantly less than non-defoliated trees for at least 2 years after defoliation. One year after defoliation, defoliated trees had similar NSC and N concentrations in woody tissues, higher polyphenol concentrations and lower re-foliation than non-defoliated trees. In the second year, however, NSC concentrations in branches were significantly higher in defoliated trees while differences in polyphenols and re-foliation disappeared and decreased, respectively. Conclusions The significant reduction in growth following defoliation was not caused by insufficient C or N availability, as frequently assumed; instead, it was probably due to growth limitations due to factors other than C or N, or to preventative C allocation to storage. This study shows an integrative approach to evaluating plant growth limitations in response to disturbance, by examining major resources other than C (e.g. N), and other C sinks besides storage and growth (e.g. defences and re-foliation). PMID:25851136</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/966057','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/966057"><span id="translatedtitle">Hydrological consequences of global <span class="hlt">warming</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Miller, Norman L.</p> <p>2009-06-01</p> <p>The 2007 Intergovernmental Panel for Climate Change indicates there is strong evidence that the atmospheric concentration of carbon dioxide far exceeds the natural range over the last 650,000 years, and this recent <span class="hlt">warming</span> of the climate system is unequivocal, resulting in more frequent <span class="hlt">extreme</span> precipitation events, earlier snowmelt runoff, increased <span class="hlt">winter</span> flood likelihoods, increased and widespread melting of snow and ice, longer and more widespread droughts, and rising sea level. The effects of recent <span class="hlt">warming</span> has been well documented and climate model projections indicate a range of hydrological impacts with likely to very likely probabilities (67 to 99 percent) of occurring with significant to severe consequences in response to a warmer lower atmosphere with an accelerating hydrologic cycle.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004AGUFMPP11B0565H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004AGUFMPP11B0565H"><span id="translatedtitle">How Were Southwest Pacific Pelagic Ecosystems Affected by <span class="hlt">Extreme</span> Global <span class="hlt">Warming</span> During the Initial Eocene Thermal Maximum?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hollis, C. J.; Crouch, E. M.; Dickens, G. R.</p> <p>2004-12-01</p> <p>Four sections in eastern New Zealand provide the only South Pacific record of the initial Eocene thermal maximum (IETM): a siliciclastic outer shelf section (Tawanui, Hawkes Bay) and three pelagic-hemipelagic sections forming an outer shelf-upper slope transect across a carbonate ramp (Muzzle, Dee and Mead Streams, Clarence Valley). Although the rocks are too indurated to yield reliable oxygen isotope data, the IETM is identified by bulk carbonate carbon isotopes as a sharp negative excursion followed by gradual recovery over 0.6 to 4.0 m. In all sections, the excursion is mirrored by terrigenous sediment concentration, due to reduced biogenic (carbonate and silica) input and increased terrigenous input. Increased precipitation under <span class="hlt">warm</span> humid conditions appears to have increased terrestrial discharge, recorded by deposition of smectitic marl in pelagic settings and illite/kaolinite-bearing smectitic mudstone in neritic settings. Eutrophic conditions are inferred for the IETM interval at Tawanui based on dysoxia, carbonate dissolution, an acme for the peridinioid dinocyst Apectodinium and abundant Toweius spp in nannofossil assemblages. Continued abundance of Toweius and replacement of Apectodinium by peridinioids of the Deflandrea complex suggests that eutrophic, albeit cooler, conditions persisted for at least 0.5 Ma after the IETM. In contrast, the IETM in Clarence Valley is marked by reduced biogenic silica content but little change in carbonate, and no evidence for carbonate dissolution. Sparse, poorly preserved palynomorphs assemblages suggest organic matter was oxidised under fully oxic conditions. Reduced numbers of upwelling indicators in the siliceous microfossil assemblage and common <span class="hlt">warm</span>-water planktic foraminifera (Morozovella spp.), nannoplankton (Discoaster spp.) and radiolarians (e.g. Podocyrtis and Theocorys spp.) signal a switch from eutrophic to oligotrophic conditions and significant <span class="hlt">warming</span> of near-surface waters. A progressive increase in</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ThApC.tmp...45L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ThApC.tmp...45L"><span id="translatedtitle">Development of heat and drought related <span class="hlt">extreme</span> weather events and their effect on <span class="hlt">winter</span> wheat yields in Germany</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lüttger, Andrea B.; Feike, Til</p> <p>2017-02-01</p> <p>Climate change constitutes a major challenge for high productivity in wheat, the most widely grown crop in Germany. <span class="hlt">Extreme</span> weather events including dry spells and heat waves, which negatively affect wheat yields, are expected to aggravate in the future. It is crucial to improve the understanding of the spatiotemporal development of such <span class="hlt">extreme</span> weather events and the respective crop-climate relationships in Germany. Thus, the present study is a first attempt to evaluate the historic development of relevant drought and heat-related <span class="hlt">extreme</span> weather events from 1901 to 2010 on county level (NUTS-3) in Germany. Three simple drought indices and two simple heat stress indices were used in the analysis. A continuous increase in dry spells over time was observed over the investigated periods from 1901-1930, 1931-1960, 1961-1990 to 2001-2010. Short and medium dry spells, i.e., precipitation-free periods longer than 5 and 8 days, respectively, increased more strongly compared to longer dry spells (longer than 11 days). The heat-related stress indices with maximum temperatures above 25 and 28 °C during critical wheat growth phases showed no significant increase over the first three periods but an especially sharp increase in the final 1991-2010 period with the increases being particularly pronounced in parts of Southwestern Germany. Trend analysis over the entire 110-year period using Mann-Kendall test revealed a significant positive trend for all investigated indices except for heat stress above 25 °C during flowering period. The analysis of county-level yield data from 1981 to 2010 revealed declining spatial yield variability and rather constant temporal yield variability over the three investigated (1981-1990, 1991-2000, and 2001-2010) decades. A clear spatial gradient manifested over time with variability in the West being much smaller than in the east of Germany. Correlating yield variability with the previously analyzed <span class="hlt">extreme</span> weather indices revealed strong</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20030053448','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20030053448"><span id="translatedtitle">The Unusual Southern Hemisphere Stratosphere <span class="hlt">Winter</span> of 2002</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Newman, Paul A.; Nash, Eric R.</p> <p>2003-01-01</p> <p>The southern hemisphere stratospheric <span class="hlt">winter</span> of 2002 was the most unusual <span class="hlt">winter</span> yet observed in the southern hemisphere climate record. Temperatures near the edge of the Antarctic polar vortex were considerably warmer than normal over the entire course of the <span class="hlt">winter</span>. The polar night jet was considerably weaker than normal, and was displaced more poleward than has been observed in previous <span class="hlt">winters</span>. These record high temperatures and weak jet resulted from a series of wave events that took place over the course of the <span class="hlt">winter</span>. The first large event occurred on 15 May, and the final <span class="hlt">warming</span> occurred on 25 October. The propagation of these wave events from the troposphere is diagnosed from time series of Eliassen-Palm flux vectors. The wave events tended to occur irregularly over the course of the <span class="hlt">winter</span>, and pre-conditioned the polar night jet for the <span class="hlt">extremely</span> large wave event of 22 September. This large wave event resulted in the first ever observed major stratospheric <span class="hlt">warming</span> in the southern hemisphere. This wave event split the Antarctic ozone hole. The combined effect of the wave events of the 2002 <span class="hlt">winter</span> resulted in the smallest ozone hole observed since 1988.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRD..121.9911S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRD..121.9911S"><span id="translatedtitle">Recent amplification of the North American <span class="hlt">winter</span> temperature dipole</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Singh, Deepti; Swain, Daniel L.; Mankin, Justin S.; Horton, Daniel E.; Thomas, Leif N.; Rajaratnam, Bala; Diffenbaugh, Noah S.</p> <p>2016-09-01</p> <p>During the <span class="hlt">winters</span> of 2013-2014 and 2014-2015, anomalously <span class="hlt">warm</span> temperatures in western North America and anomalously cool temperatures in eastern North America resulted in substantial human and environmental impacts. Motivated by the impacts of these concurrent temperature <span class="hlt">extremes</span> and the intrinsic atmospheric linkage between weather conditions in the western and eastern United States, we investigate the occurrence of concurrent "<span class="hlt">warm</span>-West/cool-East" surface temperature anomalies, which we call the "North American <span class="hlt">winter</span> temperature dipole." We find that, historically, <span class="hlt">warm</span>-West/cool-East dipole conditions have been associated with anomalous mid-tropospheric ridging over western North America and downstream troughing over eastern North America. We also find that the occurrence and severity of <span class="hlt">warm</span>-West/cool-East events have increased significantly between 1980 and 2015, driven largely by an increase in the frequency with which high-amplitude "ridge-trough" wave patterns result in simultaneous severe temperature conditions in both the West and East. Using a large single-model ensemble of climate simulations, we show that the observed positive trend in the <span class="hlt">warm</span>-West/cool-East events is attributable to historical anthropogenic emissions including greenhouse gases, but that the co-occurrence of <span class="hlt">extreme</span> western warmth and eastern cold will likely decrease in the future as <span class="hlt">winter</span> temperatures <span class="hlt">warm</span> dramatically across the continent, thereby reducing the occurrence of severely cold conditions in the East. Although our analysis is focused on one particular region, our analysis framework is generally transferable to the physical conditions shaping different types of <span class="hlt">extreme</span> events around the globe.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19850042467&hterms=extinction+behavior&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dextinction%2Bbehavior','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19850042467&hterms=extinction+behavior&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dextinction%2Bbehavior"><span id="translatedtitle">Behavior of zonal mean aerosol extinction ratio and its relationship with zonal mean temperature during the <span class="hlt">winter</span> 1978-1979 stratospheric <span class="hlt">warming</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wang, P.-H.; Mccormick, M. P.</p> <p>1985-01-01</p> <p>The behavior of the zonal mean aerosol extinction ratio in the lower stratosphere near 75 deg N and its relationship with the zonal mean temperature during the January-February 1979 stratospheric sudden <span class="hlt">warming</span> have been investigated based on the satellite sensor SAM II (Stratospheric Aerosol Measurement) and auxiliary meteorological measurements. The results indicate that distinct changes in the zonal mean aerosol extinction ratio occurred during this stratospheric sudden <span class="hlt">warming</span>. It is also found that horizontal eddy transport due to planetary waves may have played a significant role in determining the distribution of the zonal mean aerosol extinction ratio.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26111101','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26111101"><span id="translatedtitle">Climatic and biotic <span class="hlt">extreme</span> events moderate long-term responses of above- and belowground sub-Arctic heathland communities to 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>Bokhorst, Stef; Phoenix, Gareth K; Berg, Matty P; Callaghan, Terry V; Kirby-Lambert, Christopher; Bjerke, Jarle W</p> <p>2015-11-01</p> <p>Climate change impacts are not uniform across the Arctic region because interacting factors causes large variations in local ecosystem change. <span class="hlt">Extreme</span> climatic events and population cycles of herbivores occur simultaneously against a background of gradual climate <span class="hlt">warming</span> trends and can redirect ecosystem change along routes that are difficult to predict. Here, we present the results from sub-Arctic heath vegetation and its belowground micro-arthropod community in response to the two main drivers of vegetation damage in this region: <span class="hlt">extreme</span> <span class="hlt">winter</span> <span class="hlt">warming</span> events and subsequent outbreaks of the defoliating autumnal moth caterpillar (Epirrita autumnata). Evergreen dwarf shrub biomass decreased (30%) following <span class="hlt">extreme</span> <span class="hlt">winter</span> <span class="hlt">warming</span> events and again by moth caterpillar grazing. Deciduous shrubs that were previously exposed to an <span class="hlt">extreme</span> <span class="hlt">winter</span> <span class="hlt">warming</span> event were not affected by the moth caterpillar grazing, while those that were not exposed to <span class="hlt">warming</span> events (control plots) showed reduced (23%) biomass from grazing. Cryptogam cover increased irrespective of grazing or <span class="hlt">winter</span> <span class="hlt">warming</span> events. Micro-arthropods declined (46%) following <span class="hlt">winter</span> <span class="hlt">warming</span> but did not respond to changes in plant community. <span class="hlt">Extreme</span> <span class="hlt">winter</span> <span class="hlt">warming</span> and caterpillar grazing suppressed the CO2 fluxes of the ecosystem. Evergreen dwarf shrubs are disadvantaged in a future sub-Arctic with more stochastic climatic and biotic events. Given that summer <span class="hlt">warming</span> may further benefit deciduous over evergreen shrubs, event and trend climate change may both act against evergreen shrubs and the ecosystem functions they provide. This is of particular concern given that Arctic heath vegetation is typically dominated by evergreen shrubs. Other components of the vegetation showed variable responses to abiotic and biotic events, and their interaction indicates that sub-Arctic vegetation response to multiple pressures is not easy to predict from single-factor responses. Therefore, while biotic and climatic events may</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23187619','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23187619"><span id="translatedtitle">Holocene <span class="hlt">winter</span> climate variability in mid-latitude western North America.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ersek, Vasile; Clark, Peter U; Mix, Alan C; Cheng, Hai; Edwards, R Lawrence</p> <p>2012-01-01</p> <p>Water resources in western North America depend on <span class="hlt">winter</span> precipitation, yet our knowledge of its sensitivity to climate change remains limited. Similarly, understanding the potential for future loss of <span class="hlt">winter</span> snow pack requires a longer perspective on natural climate variability. Here we use stable isotopes from a speleothem in southwestern Oregon to reconstruct <span class="hlt">winter</span> climate change for much of the past 13,000 years. We find that on millennial time scales there were abrupt transitions between <span class="hlt">warm</span>-dry and cold-wet regimes. Temperature and precipitation changes on multi-decadal to century timescales are consistent with ocean-atmosphere interactions that arise from mechanisms similar to the Pacific Decadal Oscillation. <span class="hlt">Extreme</span> cold-wet and <span class="hlt">warm</span>-dry events that punctuated the Holocene appear to be sensitive to solar forcing, possibly through the influence of the equatorial Pacific on the <span class="hlt">winter</span> storm tracks reaching the US Pacific Northwest region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ESSD....9...63B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ESSD....9...63B"><span id="translatedtitle">A sudden stratospheric <span class="hlt">warming</span> compendium</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Butler, Amy H.; Sjoberg, Jeremiah P.; Seidel, Dian J.; Rosenlof, Karen H.</p> <p>2017-02-01</p> <p>Major, sudden midwinter stratospheric <span class="hlt">warmings</span> (SSWs) are large and rapid temperature increases in the <span class="hlt">winter</span> polar stratosphere are associated with a complete reversal of the climatological westerly winds (i.e., the polar vortex). These <span class="hlt">extreme</span> events can have substantial impacts on <span class="hlt">winter</span> surface climate, including increased frequency of cold air outbreaks over North America and Eurasia and anomalous <span class="hlt">warming</span> over Greenland and eastern Canada. Here we present a SSW Compendium (SSWC), a new database that documents the evolution of the stratosphere, troposphere, and surface conditions 60 days prior to and after SSWs for the period 1958-2014. The SSWC comprises data from six different reanalysis products: MERRA2 (1980-2014), JRA-55 (1958-2014), ERA-interim (1979-2014), ERA-40 (1958-2002), NOAA20CRv2c (1958-2011), and NCEP-NCAR I (1958-2014). Global gridded daily anomaly fields, full fields, and derived products are provided for each SSW event. The compendium will allow users to examine the structure and evolution of individual SSWs, and the variability among events and among reanalysis products. The SSWC is archived and maintained by NOAA's National Centers for Environmental Information (NCEI, <a href="http://dx.doi.org/10.7289/V5NS0RWP" target="_blank">doi:10.7289/V5NS0RWP</a>).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED164325.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED164325.pdf"><span id="translatedtitle"><span class="hlt">Winter</span> Survival: A Consumer's Guide to <span class="hlt">Winter</span> Preparedness.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Department of Energy, Washington, DC.</p> <p></p> <p>This booklet discusses a variety of topics to help consumers prepare for <span class="hlt">winter</span>. Tips for the home include: <span class="hlt">winterizing</span> the home, dealing with a loss of heat or power failure, and what you need to have on hand. Another section gives driving tips and what to do in a storm. Health factors include suggestions for keeping <span class="hlt">warm</span>, signs and treatment for…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AtmRe.170..176A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AtmRe.170..176A"><span id="translatedtitle">Inter-annual variations and trends of the urban <span class="hlt">warming</span> in Tehran</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Alizadeh-Choobari, O.; Ghafarian, P.; Adibi, P.</p> <p>2016-03-01</p> <p>Urbanization is an <span class="hlt">extreme</span> case of land-use change which amplifies in most cases the regional <span class="hlt">warming</span>, and highly impacts a number of sensitive sectors, particularly human health. Using near-surface daily temperature records for a 63-yr period from 1951 to 2013, temperature changes over the urban city of Tehran were examined. Statistically significant <span class="hlt">warming</span> trend of the order 0.37 °C/decade has been observed, leading to 2.3 °C rise over the entire 63-yr period, and the <span class="hlt">warming</span> trend has been intensified in recent years. The observed <span class="hlt">warming</span> in the urban city of Tehran has been more than triple the rate of change in the global average temperature, indicating that urbanization has had a significant <span class="hlt">warming</span> effect. The nighttime <span class="hlt">warming</span> (0.62 °C/decade) in the urban city of Tehran was found to be more than three times greater than the daytime <span class="hlt">warming</span> (0.17 °C/decade), resulted in a decreasing trend in the diurnal temperature range (DTR; i.e. the difference between the daytime maximum and nighttime minimum temperatures). In a similar manner, a decreasing trend in the number of cold nights was identified, and the rate was more than twice as high as the rate of increase in the number of <span class="hlt">warm</span> days. From a seasonal perspective, <span class="hlt">warming</span> trends of the urban city of Tehran have been found to be nearly identical in <span class="hlt">winter</span> and summer, with the rates of 0.35 °C/decade and 0.33 °C/decade, respectively. However, a seasonal cycle in the changes of the DTR was identified, with a stronger decrease rate in <span class="hlt">winter</span> than summer because while the nighttime <span class="hlt">warming</span> (which has been greater than the daytime <span class="hlt">warming</span>) has not changed considerably from <span class="hlt">winter</span> to summer, the daytime <span class="hlt">warming</span> has been stronger in summer.</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('http://adsabs.harvard.edu/abs/2015JGRA..120.5226L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JGRA..120.5226L"><span id="translatedtitle">Thermal and dynamical perturbations in the <span class="hlt">winter</span> polar mesosphere-lower thermosphere region associated with sudden stratospheric <span class="hlt">warmings</span> under conditions of low solar activity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lukianova, Renata; Kozlovsky, Alexander; Shalimov, Sergey; Ulich, Thomas; Lester, Mark</p> <p>2015-06-01</p> <p>The upper mesospheric neutral winds and temperatures have been derived from continuous meteor radar (MR) measurements over Sodankyla, Finland, in 2008-2014. Under conditions of low solar activity pronounced sudden mesospheric coolings linked to the major stratospheric <span class="hlt">warming</span> (SSW) in 2009 and a medium SSW in 2010 are observed while there is no observed thermal signature of the major SSW in 2013 occurred during the solar maximum. Mesosphere-ionosphere anomalies observed simultaneously by the MR, the Aura satellite, and the rapid-run ionosonde during a period of major SSW include the following features. The mesospheric temperature minimum occurs 1 day ahead of the stratospheric maximum, and the mesospheric cooling is almost of the same value as the stratospheric <span class="hlt">warming</span> (~50 K), the former decay faster than the latter. In the course of SSW, a strong mesospheric wind shear of ~70 m/s/km occurs. The wind turns clockwise (anticlockwise) from north-eastward (south-eastward) to south-westward (north-westward) above (below) 90 km. As the mesospheric temperature reaches its minimum, the gravity waves (GW) in the ionosphere with periods of 10-60 min decay abruptly while the GWs with longer periods are not affected. The effect is explained by selective filtering and/or increased turbulence near the mesopause.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4518244','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4518244"><span id="translatedtitle">Short <span class="hlt">winters</span> threaten temperate fish populations</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Farmer, Troy M.; Marschall, Elizabeth A.; Dabrowski, Konrad; Ludsin, Stuart A.</p> <p>2015-01-01</p> <p>Although climate <span class="hlt">warming</span> is expected to benefit temperate ectotherms by lengthening the summer growing season, declines in reproductive success following short, <span class="hlt">warm</span> <span class="hlt">winters</span> may counter such positive effects. Here we present long-term (1973–2010) field patterns for Lake Erie yellow perch, Perca flavescens, which show that failed annual recruitment events followed short, <span class="hlt">warm</span> <span class="hlt">winters</span>. Subsequent laboratory experimentation and field investigations revealed how reduced reproductive success following short, <span class="hlt">warm</span> <span class="hlt">winters</span> underlie these observed field patterns. Following short <span class="hlt">winters</span>, females spawn at warmer temperatures and produce smaller eggs that both hatch at lower rates and produce smaller larvae than females exposed to long <span class="hlt">winters</span>. Our research suggests that continued climate <span class="hlt">warming</span> can lead to unanticipated, negative effects on temperate fish populations. PMID:26173734</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26173734','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26173734"><span id="translatedtitle">Short <span class="hlt">winters</span> threaten temperate fish populations.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Farmer, Troy M; Marschall, Elizabeth A; Dabrowski, Konrad; Ludsin, Stuart A</p> <p>2015-07-15</p> <p>Although climate <span class="hlt">warming</span> is expected to benefit temperate ectotherms by lengthening the summer growing season, declines in reproductive success following short, <span class="hlt">warm</span> <span class="hlt">winters</span> may counter such positive effects. Here we present long-term (1973-2010) field patterns for Lake Erie yellow perch, Perca flavescens, which show that failed annual recruitment events followed short, <span class="hlt">warm</span> <span class="hlt">winters</span>. Subsequent laboratory experimentation and field investigations revealed how reduced reproductive success following short, <span class="hlt">warm</span> <span class="hlt">winters</span> underlie these observed field patterns. Following short <span class="hlt">winters</span>, females spawn at warmer temperatures and produce smaller eggs that both hatch at lower rates and produce smaller larvae than females exposed to long <span class="hlt">winters</span>. Our research suggests that continued climate <span class="hlt">warming</span> can lead to unanticipated, negative effects on temperate fish populations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NatCo...6E7724F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NatCo...6E7724F"><span id="translatedtitle">Short <span class="hlt">winters</span> threaten temperate fish populations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Farmer, Troy M.; Marschall, Elizabeth A.; Dabrowski, Konrad; Ludsin, Stuart A.</p> <p>2015-07-01</p> <p>Although climate <span class="hlt">warming</span> is expected to benefit temperate ectotherms by lengthening the summer growing season, declines in reproductive success following short, <span class="hlt">warm</span> <span class="hlt">winters</span> may counter such positive effects. Here we present long-term (1973-2010) field patterns for Lake Erie yellow perch, Perca flavescens, which show that failed annual recruitment events followed short, <span class="hlt">warm</span> <span class="hlt">winters</span>. Subsequent laboratory experimentation and field investigations revealed how reduced reproductive success following short, <span class="hlt">warm</span> <span class="hlt">winters</span> underlie these observed field patterns. Following short <span class="hlt">winters</span>, females spawn at warmer temperatures and produce smaller eggs that both hatch at lower rates and produce smaller larvae than females exposed to long <span class="hlt">winters</span>. Our research suggests that continued climate <span class="hlt">warming</span> can lead to unanticipated, negative effects on temperate fish populations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.A33E0265S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.A33E0265S"><span id="translatedtitle">A modeling study on the role of local SST <span class="hlt">warming</span> on the precipitation trends observed in north Japan during <span class="hlt">winter</span> monsoon</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sato, T.; Sugimoto, S.</p> <p>2013-12-01</p> <p>The role of sea surface temperature (SST) anomaly in modulating the terrestrial precipitation in <span class="hlt">winter</span> around Japan was investigated using a regional atmospheric model. The terrestrial precipitation over the Japan Sea side (JSS) region in northern Japan was sensitive to the offshore SST anomaly through affecting moisture flux toward Japan. Since the offshore SST was clearly warmer in the 2000s relative to the 1980s, the effect of the long-term SST variation on the terrestrial precipitation trend was examined. The experiment with realistic SST simulated the observed trend in terrestrial precipitation in the JSS region. In contrast, the precipitation trend was significantly reduced in the experiment with climatology SST. Therefore, the long-term SST trend is an important factor for the precipitation trend in the region of Japan and the adjacent oceans where SST has significant trends. Precipitation in the Pacific Ocean side of Japan indicated a weak increasing trend even without the SST trend. This suggests that the long-term variations in extra-tropical cyclones are also an important factor for precipitation trends around the Kuroshio extension.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20020060765','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20020060765"><span id="translatedtitle">Variability of <span class="hlt">Winter</span> Air Temperature in Mid-Latitude Europe</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Otterman, J.; Ardizzone, J.; Atlas, R.; Bungato, D.; Cierniewski, J.; Jusem, J. C.; Przybylak, R.; Schubert, S.; Starr, D.; Walczewski, J.</p> <p>2002-01-01</p> <p>The aim of this paper is to report <span class="hlt">extreme</span> <span class="hlt">winter</span>/early-spring air temperature (hereinafter temperature) anomalies in mid-latitude Europe, and to discuss the underlying forcing to these interannual fluctuations. <span class="hlt">Warm</span> advection from the North Atlantic in late <span class="hlt">winter</span> controls the surface-air temperature, as indicated by the substantial correlation between the speed of the surface southwesterlies over the eastern North Atlantic (quantified by a specific Index Ina) and the 2-meter level air temperatures (hereinafter Ts) over Europe, 45-60 deg N, in <span class="hlt">winter</span>. In mid-March and subsequently, the correlation drops drastically (quite often it is negative). This change in the relationship between Ts and Ina marks a transition in the control of the surface-air temperature: absorption of insolation replaces the <span class="hlt">warm</span> advection as the dominant control. This forcing by maritime-air advection in <span class="hlt">winter</span> was demonstrated in a previous publication, and is re-examined here in conjunction with <span class="hlt">extreme</span> fluctuations of temperatures in Europe. We analyze here the interannual variability at its <span class="hlt">extreme</span> by comparing <span class="hlt">warm-winter</span>/early-spring of 1989/90 with the opposite scenario in 1995/96. For these two December-to-March periods the differences in the monthly mean temperature in Warsaw and Torun, Poland, range above 10 C. Short-term (shorter than a month) fluctuations of the temperature are likewise very strong. We conduct pentad-by-pentad analysis of the surface-maximum air temperature (hereinafter Tmax), in a selected location, examining the dependence on Ina. The increased cloudiness and higher amounts of total precipitable water, corollary effects to the <span class="hlt">warm</span> low-level advection. in the 1989/90 <span class="hlt">winter</span>, enhance the positive temperature anomalies. The analysis of the ocean surface winds is based on the Special Sensor Microwave/Imager (SSM/I) dataset; ascent rates, and over land wind data are from the European Centre for Medium-Range Weather Forecasts (ECMWF); maps of 2-m temperature, cloud</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMGC31B0454S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMGC31B0454S"><span id="translatedtitle">On-Going Temperature <span class="hlt">Extremes</span> in Siberia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shulgina, T. M.; Gordov, E. P.</p> <p>2014-12-01</p> <p>Ongoing global climate changes accompanied by the restructuring of global processes in the atmosphere and biosphere are strongly pronounced in the Northern Eurasia regions, especially in Siberia. Temperature trends (grows up to 0.5 °C per decade), more frequent occurrence of temperature <span class="hlt">extremes</span> provoked serious natural disasters (2010 heat waves in Russia, 2013 flood in Russia's Far East) led to socio-economical impact (crop damages, infrastructure failures, respectively). To get reliable knowledge on location, frequency and magnitude of observed <span class="hlt">extremes</span> we have studied daily max/min temperature trends based on ECMWF ERA Interim Reanalysis data (0,25°×0,25°). This dataset is most accurately reproduces observed temperature behavior in the region. Statistical analysis of daily temperature time series (1979-2012) indicates the asymmetric changes in distribution tails of such <span class="hlt">extreme</span> indices as <span class="hlt">warm</span>/cold days/nights. Namely, the <span class="hlt">warming</span> during <span class="hlt">winter</span> cold nights is stronger than during <span class="hlt">warm</span> nights, especially over the north of Siberia. Increases in minimum temperatures are more significant than in maximum temperatures. <span class="hlt">Warming</span> determined at the high latitudes of the region is achieved mostly due to <span class="hlt">winter</span> temperature changes. South area of Siberia has slightly cooling during <span class="hlt">winter</span> and summer. Results obtained provide regional decision-makers with detailed high spatial and temporal resolution climatic information required for adaptation and mitigation measures development. Calculations presented have been realized using information-computational web-GIS system "Climate" (http://climate.scert.ru/) which automatically generates the archive of calculated fields ready for multidisciplinary studies of regional climate change impacts. The authors acknowledge partial financial support for this research from the RFBR (13-05-12034, 14-05-00502), SB RAS 131 and VIII.80.2.1.) and grant of the President of RF (№ 181).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.C33B0817M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.C33B0817M"><span id="translatedtitle">Assimilation of Airborne Snow Observatory Snow Water Equivalent to Improve Runoff Forecasting Model Performance and Reservoir Management During <span class="hlt">Warm</span> and Dry <span class="hlt">Winters</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>McGurk, B. J.; Painter, T. H.</p> <p>2015-12-01</p> <p>The Airborne Snow Observatory (ASO) NASA-JPL demonstration mission has collected detailed snow information for portions of the Tuolumne Basin in California for three years, 2013 - 2015. Both 2014 and 2015 were low snow years, and 2015 was exceptionally <span class="hlt">warm</span> and analogous to future years after climate change. The ASO uses an imaging spectrometer and LiDAR sensors mounted in an aircraft to collect snow depth and extent data, and snow albedo. By combining ground and modeled density fields, the ~weekly flights over the Tuolumne produced both basin-wide and detailed sub-basin snow water equivalent (SWE) estimates that were provided to Hetch Hetchy Reservoir operators. The data were also assimilated into an hydrologic simulation model in an attempt to improve the accuracy and timing of a runoff forecasting tool that can be used to improve the management of Hetch Hetchy Reservoir, the source of 85% of the water supply for 2.6 million people on the San Francisco Peninsula. The USGS Precipitation Runoff Modeling System was calibrated to the 1181 square kilometer basin and simulation results compared to observed runoff with and without assimilation of ASO data. Simulated and observed were also compared with observed with both single updates associated with each flight, and with sequential updates from each flight. Sequential updating was found to improve correlation between observed and simulated reservoir inflows, and there by improve the ability of reservoir operators to more efficiently allocate the last half of the recession limb of snowmelt inflow and be assured of filling the reservoir and minimizing ecologically-damaging late season spills.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005RPPh...68.1343H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005RPPh...68.1343H"><span id="translatedtitle">Global <span class="hlt">warming</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Houghton, John</p> <p>2005-06-01</p> <p>'Global <span class="hlt">warming</span>' is a phrase that refers to the effect on the climate of human activities, in particular the burning of fossil fuels (coal, oil and gas) and large-scale deforestation, which cause emissions to the atmosphere of large amounts of 'greenhouse gases', of which the most important is carbon dioxide. Such gases absorb infrared radiation emitted by the Earth's surface and act as blankets over the surface keeping it warmer than it would otherwise be. Associated with this <span class="hlt">warming</span> are changes of climate. The basic science of the 'greenhouse effect' that leads to the <span class="hlt">warming</span> is well understood. More detailed understanding relies on numerical models of the climate that integrate the basic dynamical and physical equations describing the complete climate system. Many of the likely characteristics of the resulting changes in climate (such as more frequent heat waves, increases in rainfall, increase in frequency and intensity of many <span class="hlt">extreme</span> climate events) can be identified. Substantial uncertainties remain in knowledge of some of the feedbacks within the climate system (that affect the overall magnitude of change) and in much of the detail of likely regional change. Because of its negative impacts on human communities (including for instance substantial sea-level rise) and on ecosystems, global <span class="hlt">warming</span> is the most important environmental problem the world faces. Adaptation to the inevitable impacts and mitigation to reduce their magnitude are both necessary. International action is being taken by the world's scientific and political communities. Because of the need for urgent action, the greatest challenge is to move rapidly to much increased energy efficiency and to non-fossil-fuel energy sources.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014TCD.....8.5911S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014TCD.....8.5911S"><span id="translatedtitle">Weak precipitation, <span class="hlt">warm</span> <span class="hlt">winters</span> and springs impact glaciers of south slopes of Mt. Everest (central Himalaya) in the last two decades (1994-2013)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Salerno, F.; Guyennon, N.; Thakuri, S.; Viviano, G.; Romano, E.; Vuillermoz, E.; Cristofanelli, P.; Stocchi, P.; Agrillo, G.; Ma, Y.; Tartari, G.</p> <p>2014-12-01</p> <p>Studies on recent climate trends from the Himalayan range are limited, and even completely absent at high elevation. This contribution specifically explores the southern slopes of Mt. Everest (central Himalaya), analyzing the minimum, maximum, and mean temperature and precipitation time series reconstructed from seven stations located between 2660 and 5600m a.s.l. over the last twenty years (1994-2013). We complete this analysis with data from all the existing ground weather stations located on both sides of the mountain range (Koshi Basin) over the same period. Overall we observe that the main and more significant increase in temperature is concentrated outside of the monsoon period. At higher elevations minimum temperature (0.072 ± 0.011 °C a-1, p < 0.001) increased far more than maximum temperature (0.009 ± 0.012 °C a-1, p > 0.1), while mean temperature increased by 0.044 ± 0.008 °C a-1, p < 0.05. Moreover, we note a substantial precipitation weakening (9.3 ± 1.8mm a-1, p < 0.01 during the monsoon season). The annual rate of decrease at higher elevation is similar to the one at lower altitudes on the southern side of the Koshi Basin, but here the drier conditions of this remote environment make the fractional loss much more consistent (47% during the monsoon period). This study contributes to change the perspective on which climatic driver (temperature vs. precipitation) led mainly the glacier responses in the last twenty years. The main implications are the following: (1) the negative mass balances of glaciers observed in this region can be more ascribed to less accumulation due to weaker precipitation than to an increase of melting processes. (2) The melting processes have only been favored during <span class="hlt">winter</span> and spring months and close to the glaciers terminus. (3) A decreasing of the probability of snowfall has significantly interested only the glaciers ablation zones (10%, p < 0.05), but the magnitude of this phenomenon is decidedly lower than the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015TCry....9.1229S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015TCry....9.1229S"><span id="translatedtitle">Weak precipitation, <span class="hlt">warm</span> <span class="hlt">winters</span> and springs impact glaciers of south slopes of Mt. Everest (central Himalaya) in the last 2 decades (1994-2013)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Salerno, F.; Guyennon, N.; Thakuri, S.; Viviano, G.; Romano, E.; Vuillermoz, E.; Cristofanelli, P.; Stocchi, P.; Agrillo, G.; Ma, Y.; Tartari, G.</p> <p>2015-06-01</p> <p>Studies on recent climate trends from the Himalayan range are limited, and even completely absent at high elevation (> 5000 m a.s.l.). This study specifically explores the southern slopes of Mt. Everest, analyzing the time series of temperature and precipitation reconstructed from seven stations located between 2660 and 5600 m a.s.l. during 1994-2013, complemented with the data from all existing ground weather stations located on both sides of the mountain range (Koshi Basin) over the same period. Overall we find that the main and most significant increase in temperature is concentrated outside of the monsoon period. Above 5000 m a.s.l. the increasing trend in the time series of minimum temperature (+0.072 °C yr-1) is much stronger than of maximum temperature (+0.009 °C yr-1), while the mean temperature increased by +0.044 °C yr-1. Moreover, we note a substantial liquid precipitation weakening (-9.3 mm yr-1) during the monsoon season. The annual rate of decrease in precipitation at higher elevations is similar to the one at lower elevations on the southern side of the Koshi Basin, but the drier conditions of this remote environment make the fractional loss much more consistent (-47% during the monsoon period). Our results challenge the assumptions on whether temperature or precipitation is the main driver of recent glacier mass changes in the region. The main implications are the following: (1) the negative mass balances of glaciers observed in this region can be more ascribed to a decrease in accumulation (snowfall) than to an increase in surface melting; (2) the melting has only been favoured during <span class="hlt">winter</span> and spring months and close to the glaciers terminus; (3) a decrease in the probability of snowfall (-10%) has made a significant impact only at glacier ablation zone, but the magnitude of this decrease is distinctly lower than the observed decrease in precipitation; (4) the decrease in accumulation could have caused the observed decrease in glacier flow</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRG..121..895L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRG..121..895L"><span id="translatedtitle">Fourfold higher tundra volatile emissions due to arctic summer <span class="hlt">warming</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lindwall, Frida; Schollert, Michelle; Michelsen, Anders; Blok, Daan; Rinnan, Riikka</p> <p>2016-03-01</p> <p>Biogenic volatile organic compounds (BVOCs), which are mainly emitted by vegetation, may create either positive or negative climate forcing feedbacks. In the Subarctic, BVOC emissions are highly responsive to temperature, but the effects of climatic <span class="hlt">warming</span> on BVOC emissions have not been assessed in more <span class="hlt">extreme</span> arctic ecosystems. The Arctic undergoes rapid climate change, with air temperatures increasing at twice the rate of the global mean. Also, the amount of <span class="hlt">winter</span> precipitation is projected to increase in large areas of the Arctic, and it is unknown how <span class="hlt">winter</span> snow depth affects BVOC emissions during summer. Here we examine the responses of BVOC emissions to experimental summer <span class="hlt">warming</span> and <span class="hlt">winter</span> snow addition—each treatment alone and in combination—in an arctic heath during two growing seasons. We observed a 280% increase relative to ambient in BVOC emissions in response to a 4°C summer <span class="hlt">warming</span>. Snow addition had minor effects on growing season BVOC emissions after one <span class="hlt">winter</span> but decreased BVOC emissions after the second <span class="hlt">winter</span>. We also examined differences between canopy and air temperatures and found that the tundra canopy surface was on average 7.7°C and maximum 21.6°C warmer than air. This large difference suggests that the tundra surface temperature is an important driver for emissions of BVOCs, which are temperature dependent. Our results demonstrate a strong response of BVOC emissions to increasing temperatures in the Arctic, suggesting that emission rates will increase with climate <span class="hlt">warming</span> and thereby feed back to regional climate change.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AdAtS..34..289W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AdAtS..34..289W"><span id="translatedtitle">Changes in mean and <span class="hlt">extreme</span> temperature and precipitation over the arid region of northwestern China: Observation and projection</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Yujie; Zhou, Botao; Qin, Dahe; Wu, Jia; Gao, Rong; Song, Lianchun</p> <p>2017-03-01</p> <p>This paper reports a comprehensive study on the observed and projected spatiotemporal changes in mean and <span class="hlt">extreme</span> climate over the arid region of northwestern China, based on gridded observation data and CMIP5 simulations under the RCP4.5 and RCP8.5 scenarios. The observational results reveal an increase in annual mean temperature since 1961, largely attributable to the increase in minimum temperature. The annual mean precipitation also exhibits a significant increasing tendency. The precipitation amount in the most recent decade was greater than in any preceding decade since 1961. Seasonally, the greatest increase in temperature and precipitation appears in <span class="hlt">winter</span> and in summer, respectively. Widespread significant changes in temperature-related <span class="hlt">extremes</span> are consistent with <span class="hlt">warming</span>, with decreases in cold <span class="hlt">extremes</span> and increases in <span class="hlt">warm</span> <span class="hlt">extremes</span>. The <span class="hlt">warming</span> of the coldest night is greater than that of the warmest day, and changes in cold and <span class="hlt">warm</span> nights are more evident than for cold and <span class="hlt">warm</span> days. <span class="hlt">Extreme</span> precipitation and wet days exhibit an increasing trend, and the maximum number of consecutive dry days shows a tendency toward shorter duration. Multi-model ensemble mean projections indicate an overall continual increase in temperature and precipitation during the 21st century. Decreases in cold <span class="hlt">extremes</span>, increases in <span class="hlt">warm</span> <span class="hlt">extremes</span>, intensification of <span class="hlt">extreme</span> precipitation, increases in wet days, and decreases in consecutive dry days, are expected under both emissions scenarios, with larger changes corresponding to stronger radiative forcing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110008075','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110008075"><span id="translatedtitle">Titan's Emergence from <span class="hlt">Winter</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Flasar, F. Michael; Achterberg, Richard; Jennings, Donald; Schinder, Paul</p> <p>2011-01-01</p> <p>We summarize the changes in Titans thermal structure derived from Cassini CIRS and radio-occultation data during the transition from <span class="hlt">winter</span> to early spring. Titan's surface, and middle atmosphere show noticeable seasonal change, whereas that in most of the troposphere is mated. This can be understood in terms of the relatively small radiative relaxation time in the middle atmosphere and much larger time scale in the troposphere. The surface exhibits seasonal change because the heat capacity in an annual skin depth is much smaller than that in the lowest scale height of the troposphere. Surface temperatures rise 1 K at raid and high latitudes in the <span class="hlt">winter</span> northern hemisphere and cool in the southern hemisphere. Changes in in the middle atmosphere are more complicated. Temperatures in the middle stratosphere (approximately 1 mbar) increase by a few kelvin at mid northern latitudes, but those at high latitudes first increase as that region moves out of <span class="hlt">winter</span> shadow, and then decrease. This probably results from the combined effect of increased solar heating as the suit moves higher in the sky and the decreased adiabatic <span class="hlt">warming</span> as the sinking motions associated with the cross-equatorial meridional cell weaken. Consistent with this interpretation, the <span class="hlt">warm</span> temperatures observed higher up at the <span class="hlt">winter</span> polar stratopause cool significantly.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMGC43D1086K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMGC43D1086K"><span id="translatedtitle">How Much <span class="hlt">Winter</span> Stratospheric Polar-cap <span class="hlt">Warming</span> Is Explained By Upward-propagating Planetary Waves In CMIP5 Models?: Part 1. An Indirect Approach Using A Wave Interference Index</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.; Kim, B.</p> <p>2013-12-01</p> <p>The breaking of upward-propagating planetary (typically characterized by the combination of zonal wave number 1 and 2) waves in the stratosphere is regarded as one of the factors that provoke the sudden stratospheric <span class="hlt">warming</span> (SSW) and the accompanying collapse of stratospheric polar vortex during <span class="hlt">winter</span>. It is also known that if the anomalous stationary wave pattern is in phase with that of the climatology during a certain period, this period is dynamically favorable for the upward propagation and amplification of planetary waves. This kind of phenomenon that amplitude of resultant wave increases by combining two or more waves in phase is called the constructive interference. Our research evaluates whether and to what degree the Coupled Model Intercomparison Project Phase 5 (CMIP5) models simulate such a relation between tropospheric wave interference and Northern polar stratosphere temperature anomaly during <span class="hlt">winter</span>. Here the 500-hPa wave interference index (WII500) is defined as the coefficient that is obtained by projecting the anomaly of wave number 1 and 2 components of 500-hPa geopotential height onto its climatology. Using monthly outputs of the CMIP5 historical runs currently available to us, we examine the lagged relationship (R-square) between the WII500 during November-December-January (NDJ) and the polar-cap temperature anomaly at 50 hPa (PCT50) during December-January-February (DJF) on an interannual timescale. By sampling uncertainty in R-squares of 33-yr samples (chosen fit with the modern reanalysis period, 1980-2012) with bootstrap resampling, we obtain the sampled medians for all models. The observed relations are then calculated using six reanalyses (ERA-40, ERA-Interim, JRA-25, MERRA, NCEP-R1, and NCEP-R2), and the 5-95% confidence interval of their observed R-square is obtained again with bootstrap resampling of all six reanalyses blended. Then we evaluate which CMIP5 model simulates the WII500-PCT50 relation within the probable range of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMGC21D0874G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMGC21D0874G"><span id="translatedtitle">Ongoing climatic <span class="hlt">extreme</span> dynamics in Siberia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gordov, E. P.; Shulgina, T. M.; Okladnikov, I. G.; Titov, A. G.</p> <p>2013-12-01</p> <p>Ongoing global climate changes accompanied by the restructuring of global processes in the atmosphere and biosphere are strongly pronounced in the Northern Eurasia regions, especially in Siberia. Recent investigations indicate not only large changes in averaged climatic characteristics (Kabanov and Lykosov, 2006, IPCC, 2007; Groisman and Gutman, 2012), but more frequent occurrence and stronger impacts of climatic <span class="hlt">extremes</span> are reported as well (Bulygina et al., 2007; IPCC, 2012: Climate <span class="hlt">Extremes</span>, 2012; Oldenborh et al., 2013). This paper provides the results of daily temperature and precipitation <span class="hlt">extreme</span> dynamics in Siberia for the last three decades (1979 - 2012). Their seasonal dynamics is assessed using 10th and 90th percentile-based threshold indices that characterize frequency, intensity and duration of climatic <span class="hlt">extremes</span>. To obtain the geographical pattern of these variations with high spatial resolution, the sub-daily temperature data from ECMWF ERA-Interim reanalysis and daily precipitation amounts from APHRODITE JMA dataset were used. All <span class="hlt">extreme</span> indices and linear trend coefficients have been calculated using web-GIS information-computational platform Climate (http://climate.scert.ru/) developed to support collaborative multidisciplinary investigations of regional climatic changes and their impacts (Gordov et al., 2012). Obtained results show that seasonal dynamics of daily temperature <span class="hlt">extremes</span> is asymmetric for tails of cold and <span class="hlt">warm</span> temperature <span class="hlt">extreme</span> distributions. Namely, the intensity of <span class="hlt">warming</span> during cold nights is higher than during <span class="hlt">warm</span> nights, especially at high latitudes of Siberia. The similar dynamics is observed for cold and <span class="hlt">warm</span> day-time temperatures. Slight summer cooling was observed in the central part of Siberia. It is associated with decrease in <span class="hlt">warm</span> temperature <span class="hlt">extremes</span>. In the southern Siberia in <span class="hlt">winter</span>, we also observe some cooling mostly due to strengthening of the cold temperature <span class="hlt">extremes</span>. Changes in daily precipitation <span class="hlt">extremes</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ClDy...46.4027G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ClDy...46.4027G"><span id="translatedtitle"><span class="hlt">Extreme</span> air-sea interaction over the North Atlantic subpolar gyre during the <span class="hlt">winter</span> of 2013-2014 and its sub-surface legacy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Grist, Jeremy P.; Josey, Simon A.; Jacobs, Zoe L.; Marsh, Robert; Sinha, Bablu; Van Sebille, Erik</p> <p>2016-06-01</p> <p>Exceptionally low North American temperatures and record-breaking precipitation over the British Isles during <span class="hlt">winter</span> 2013-2014 were interconnected by anomalous ocean evaporation over the North Atlantic subpolar gyre region (SPG). This evaporation (or oceanic latent heat release) was accompanied by strong sensible heat loss to the atmosphere. The enhanced heat loss over the SPG was caused by a combination of surface westerly winds from the North American continent and northerly winds from the Nordic Seas region that were colder, drier and stronger than normal. A distinctive feature of the air-sea exchange was that the enhanced heat loss spanned the entire width of the SPG, with evaporation anomalies intensifying in the east while sensible heat flux anomalies were slightly stronger upstream in the west. The immediate impact of the strong air-sea fluxes on the ocean-atmosphere system included a reduction in ocean heat content of the SPG and a shift in basin-scale pathways of ocean heat and atmospheric freshwater transport. Atmospheric reanalysis data and the EN4 ocean data set indicate that a longer-term legacy of the <span class="hlt">winter</span> has been the enhanced formation of a particularly dense mode of Subpolar Mode Water (SPMW)—one of the precursors of North Atlantic Deep Water and thus an important component of the Atlantic Meridional Overturning Circulation. Using particle trajectory analysis, the likely dispersal of newly-formed SPMW is evaluated, providing evidence for the re-emergence of anomalously cold SPMW in early <span class="hlt">winter</span> 2014/2015.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22150424','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22150424"><span id="translatedtitle">Nutrition for <span class="hlt">winter</span> sports.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Meyer, Nanna L; Manore, Melinda M; Helle, Christine</p> <p>2011-01-01</p> <p><span class="hlt">Winter</span> sports are played in cold conditions on ice or snow and often at moderate to high altitude. The most important nutritional challenges for <span class="hlt">winter</span> sport athletes exposed to environmental <span class="hlt">extremes</span> include increased energy expenditure, accelerated muscle and liver glycogen utilization, exacerbated fluid loss, and increased iron turnover. <span class="hlt">Winter</span> sports, however, vary greatly regarding their nutritional requirements due to variable physiological and physique characteristics, energy and substrate demands, and environmental training and competition conditions. What most <span class="hlt">winter</span> sport athletes have in common is a relatively lean physique and high-intensity training periods, thus they require greater energy and nutrient intakes, along with adequate food and fluid before, during, and after training. Event fuelling is most challenging for cross-country skiers competing in long events, ski jumpers aiming to reduce their body weight, and those <span class="hlt">winter</span> sport athletes incurring repeated qualification rounds and heats. These athletes need to ensure carbohydrate availability throughout competition. Finally, <span class="hlt">winter</span> sport athletes may benefit from dietary and sport supplements; however, attention should be paid to safety and efficacy if supplementation is considered.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=wildflowers&pg=2&id=EJ256876','ERIC'); return false;" href="http://eric.ed.gov/?q=wildflowers&pg=2&id=EJ256876"><span id="translatedtitle"><span class="hlt">Winter</span> Weeds.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Lindberg, Lois</p> <p>1981-01-01</p> <p>Try to learn all you can about a plant in the <span class="hlt">winter</span>. As the season changes, you can see what the dried seed pod is like in bloom. You are a convert if you notice a spectacular show of summer wildflowers and wonder what sort of <span class="hlt">winter</span> weed will result. (Author/CM)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013GeoRL..40.6208V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013GeoRL..40.6208V"><span id="translatedtitle"><span class="hlt">Extreme</span> Arctic cyclones in CMIP5 historical simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vavrus, Stephen J.</p> <p>2013-12-01</p> <p>attention is being paid to <span class="hlt">extreme</span> weather, including recent high-profile events involving very destructive cyclones. In summer 2012, a historically powerful cyclone traversed the Arctic, a region experiencing rapid <span class="hlt">warming</span> and dramatic loss of ice and snow cover. This study addresses whether such powerful storms are an emerging expression of anthropogenic climate change by investigating simulated <span class="hlt">extreme</span> Arctic cyclones during the historical period (1850-2005) among global climate models in the Coupled Model Intercomparison Project 5 (CMIP5) archive. These general circulation models are able to simulate <span class="hlt">extreme</span> pressures associated with strong polar storms without a significant dependence on model resolution. The models display realism by generating <span class="hlt">extreme</span> Arctic storms primarily around subpolar cyclone regions (Aleutian and Icelandic) and preferentially during <span class="hlt">winter</span>. Simulated secular trends in Arctic mean sea level pressure and <span class="hlt">extreme</span> cyclones are equivocal; both indicate increasing storminess in some regions, but the magnitude of changes to date are modest compared with future projections.</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('http://adsabs.harvard.edu/abs/2016EGUGA..1816504O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1816504O"><span id="translatedtitle">The role of convection permitting modeling to evaluate the contribution of the anthropogenic climate change on the UK <span class="hlt">Winter</span> 2013-2014 <span class="hlt">extreme</span> rain</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Omrani, Hiba; Vautard, Robert</p> <p>2016-04-01</p> <p>During the <span class="hlt">winter</span> 2013/2014, the UK saw heavy rainfalls associated with a succession of storms reaching Southern England causing widespread flooding, power cuts and major disruptions to transport. The January precipitation set a record for several rain gauge stations in Southern England. The aim of this study is to evaluate the contribution of the anthropogenic climate change, represented by a modification of the sea surface temperature (SST) on the January precipitation. For that, we conducted a sensitivity experiment by running a set of two-months simulations using WRF model with 50km horizontal resolution simulation and 2 km convection permitting simulation centered over the southern UK. We also investigated the sensitivity to the model physics. Results show that the horizontal resolution plays an important role for interpreting the results. Indeed, the low resolution simulation showed no robust signal to attribute this event. However, the convection permitting simulations gave more consistent results over the studied area.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21265150','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21265150"><span id="translatedtitle">[Passive nighttime <span class="hlt">warming</span> (PNW) system, its design and <span class="hlt">warming</span> effect].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chen, Jin; Yang, Fei; Zhang, Bin; Tian, Yun-lu; Dong, Wen-jun; Zhang, Wei-jian</p> <p>2010-09-01</p> <p>Based on the technique of passive nighttime <span class="hlt">warming</span> (PNW), a convenient and energy-saving PNW facility was designed for a rice-wheat cropping system in Danyang, Jiangsu Province. The facility could guarantee 15.75 m2 effective sampling area, with a homogeneous amplitude of increased temperature, and making the nighttime canopy temperature during whole rice growth season increased averagely by 1.1 degrees C and the nighttime canopy temperature and 5 cm soil temperature during whole <span class="hlt">winter</span> wheat growth period increased averagely by 1.3 degrees C and 0.8 degrees C, respectively. During the operation period of the facility, the variation trends of the canopy temperature and 5 cm soil temperature during the whole growth periods of rice and <span class="hlt">winter</span> wheat in the <span class="hlt">warming</span> plots were similar to those of the control. Though the facility slightly decreased the soil moisture content during <span class="hlt">winter</span> wheat growth period, wheat growth was less impacted. The application of this facility in our main production areas of rice and <span class="hlt">winter</span> wheat showed that the facility could advance the initial blossoming stages of rice and <span class="hlt">winter</span> wheat averagely by 3 d and 5 d, respectively. In despite of the discrepancy in the <span class="hlt">warming</span> effect among different regions and seasons, this energy-saving facility was reliable for the field research on crop responses to climate <span class="hlt">warming</span>, when the homogeneity of increased temperature, the effective area, and the effects on crop growth period were taken into comprehensive consideration.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5095811','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5095811"><span id="translatedtitle">Recent amplification of the North American <span class="hlt">winter</span> temperature dipole</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Swain, Daniel L.; Mankin, Justin S.; Horton, Daniel E.; Thomas, Leif N.; Rajaratnam, Bala; Diffenbaugh, Noah S.</p> <p>2016-01-01</p> <p>Abstract During the <span class="hlt">winters</span> of 2013–2014 and 2014–2015, anomalously <span class="hlt">warm</span> temperatures in western North America and anomalously cool temperatures in eastern North America resulted in substantial human and environmental impacts. Motivated by the impacts of these concurrent temperature <span class="hlt">extremes</span> and the intrinsic atmospheric linkage between weather conditions in the western and eastern United States, we investigate the occurrence of concurrent “warm‐West/cool‐East” surface temperature anomalies, which we call the “North American <span class="hlt">winter</span> temperature dipole.” We find that, historically, warm‐West/cool‐East dipole conditions have been associated with anomalous mid‐tropospheric ridging over western North America and downstream troughing over eastern North America. We also find that the occurrence and severity of warm‐West/cool‐East events have increased significantly between 1980 and 2015, driven largely by an increase in the frequency with which high‐amplitude “ridge‐trough” wave patterns result in simultaneous severe temperature conditions in both the West and East. Using a large single‐model ensemble of climate simulations, we show that the observed positive trend in the warm‐West/cool‐East events is attributable to historical anthropogenic emissions including greenhouse gases, but that the co‐occurrence of <span class="hlt">extreme</span> western warmth and eastern cold will likely decrease in the future as <span class="hlt">winter</span> temperatures <span class="hlt">warm</span> dramatically across the continent, thereby reducing the occurrence of severely cold conditions in the East. Although our analysis is focused on one particular region, our analysis framework is generally transferable to the physical conditions shaping different types of <span class="hlt">extreme</span> events around the globe. PMID:27840780</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=earth+AND+warming&pg=4&id=EJ391198','ERIC'); return false;" href="http://eric.ed.gov/?q=earth+AND+warming&pg=4&id=EJ391198"><span id="translatedtitle">Global <span class="hlt">Warming</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Hileman, Bette</p> <p>1989-01-01</p> <p>States the foundations of the theory of global <span class="hlt">warming</span>. Describes methodologies used to measure the changes in the atmosphere. Discusses steps currently being taken in the United States and the world to slow the <span class="hlt">warming</span> trend. Recognizes many sources for the <span class="hlt">warming</span> and the possible effects on the earth. (MVL)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Biological+AND+warfare&pg=2&id=EJ297264','ERIC'); return false;" href="http://eric.ed.gov/?q=Biological+AND+warfare&pg=2&id=EJ297264"><span id="translatedtitle">Nuclear <span class="hlt">Winter</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Ehrlich, Anne</p> <p>1984-01-01</p> <p>"Nuclear <span class="hlt">Winter</span>" was recently coined to describe the climatic and biological effects of a nuclear war. These effects are discussed based on models, simulations, scenarios, and projections. Effects on human populations are also considered. (JN)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2769945','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2769945"><span id="translatedtitle">Increases in Whole Blood Glucose Measurements Using Optically Based Self-Monitoring of Blood Glucose Analyzers Due to <span class="hlt">Extreme</span> Canadian <span class="hlt">Winters</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>Cembrowski, George C.; Smith, Barbara; O'Malley, Ellen M.</p> <p>2009-01-01</p> <p>Background Temperature and humidity have been reported to influence the results of whole blood glucose (WBG) measurements. Methods To determine whether patient WBG values were affected by seasonal variation, we conducted a retrospective analysis of 3 years' worth of weekly averages of patient WBG in five Edmonton hospitals. Results In all five hospitals, the <span class="hlt">winter</span> WBG averages were consistently higher than the summer WBG averages, with the differences varying between 5% and 9%. Whole blood glucose averages were negatively correlated with the outside temperature. This seasonal variation was not observed in weekly patient averages of specimens run in a central hospital laboratory. Interpretation It is probable that the seasonal variation of WBG arises from the very low indoor humidities that are associated with external subzero temperatures. These increases in WBG in cold weather may be due to limitations in the WBG measuring systems when operated in decreased humidities and/or increased evaporation of the blood sample during the blood glucose measurement process. The implications of this seasonal variation are significant in that it (1) introduces increased variability in patient WBG, (2) may result in increased glucose-lowering therapy during periods of external cold and low indoor humidity, and (3) confounds evaluations of WBG meter technology in geographic regions of subzero temperature and low indoor humidity. To mitigate the risk of diagnosing and treating factitious hyperglycemia, the humidity of patient care areas must be strictly controlled. PMID:20144309</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRD..122.2269H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRD..122.2269H"><span id="translatedtitle">Can climate-effective land management reduce regional <span class="hlt">warming</span>?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hirsch, A. L.; Wilhelm, M.; Davin, E. L.; Thiery, W.; Seneviratne, S. I.</p> <p>2017-02-01</p> <p>Limiting global <span class="hlt">warming</span> to well below 2°C is an imminent challenge for humanity. However, even if this global target can be met, some regions are still likely to experience substantial <span class="hlt">warming</span> relative to others. Using idealized global climate simulations, we examine the potential of land management options in affecting regional climate, with a focus on crop albedo enhancement and irrigation (climate-effective land management). The implementation is performed over all crop regions globally to provide an upper bound. We find that the implementation of both crop albedo enhancement and irrigation can reduce hot temperature <span class="hlt">extremes</span> by more than 2°C in North America, Eurasia, and India over the 21st century relative to a scenario without management application. The efficacy of crop albedo enhancement scales with the magnitude, where a cooling response exceeding 0.5°C for hot temperature <span class="hlt">extremes</span> was achieved with a large (i.e., ≥0.08) change in crop albedo. Regional differences were attributed to the surface energy balance response with temperature changes mostly explained by latent heat flux changes for irrigation and net shortwave radiation changes for crop albedo enhancement. However, limitations do exist, where we identify <span class="hlt">warming</span> over the <span class="hlt">winter</span> months when climate-effective land management is temporarily suspended. This was associated with persistent cloud cover that enhances longwave <span class="hlt">warming</span>. It cannot be confirmed if the magnitude of this feedback is reproducible in other climate models. Our results overall demonstrate that regional <span class="hlt">warming</span> of hot <span class="hlt">extremes</span> in our climate model can be partially mitigated when using an idealized treatment of climate-effective land management.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ThApC.tmp..141W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ThApC.tmp..141W"><span id="translatedtitle">Trends in temperature <span class="hlt">extremes</span> over nine integrated agricultural regions in China, 1961-2011</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wu, Xushu; Wang, Zhaoli; Zhou, Xiaowen; Lai, Chengguang; Chen, Xiaohong</p> <p>2016-06-01</p> <p>By characterizing the patterns of temperature <span class="hlt">extremes</span> over nine integrated agricultural regions (IARs) in China from 1961 to 2011, this study performed trend analyses on 16 <span class="hlt">extreme</span> temperature indices using a high-resolution (0.5° × 0.5°) daily gridded dataset and the Mann-Kendall method. The results show that annually, at both daytime and nighttime, cold <span class="hlt">extremes</span> significantly decreased but <span class="hlt">warm</span> <span class="hlt">extremes</span> significantly increased across all IARs. Overall, nighttimes tended to <span class="hlt">warm</span> faster than daytimes. Diurnal temperature ranges (DTR) diminished, apart from the mid-northern Southwest China Region and the mid-Loess Plateau Region. Seasonally, DTR widely diminished across all IARs during the four seasons except for spring. Higher minimum daily minimum temperature (TNn) and maximum daily maximum temperature (TXx), in both summer and <span class="hlt">winter</span>, were recorded for most IARs except for the Huang-Huai-Hai Region; in autumn, all IARs generally encountered higher TNn and TXx. In all seasons, <span class="hlt">warming</span> was observed at daytime and nighttime but, again, nighttimes <span class="hlt">warmed</span> faster than daytimes. The results also indicate a more rapid <span class="hlt">warming</span> trend in Northern and Western China than in Southern and Eastern China, with accelerated <span class="hlt">warming</span> at high elevations. The increases in TNn and TXx might cause a reduction in agriculture yield in spring over Northern China, while such negative impact might occur in Southern China during summer. In autumn and <span class="hlt">winter</span>, however, the negative impact possibly occurred in most of the IARs. Moreover, increased TXx in the Pearl River Delta and Yangtze River Delta is possibly related to rapid local urbanization. Climatically, the general increase in temperature <span class="hlt">extremes</span> across Chinese IARs may be induced by strengthened Northern Hemisphere Subtropical High or weakened Northern Hemisphere Polar Vortex.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27069614','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27069614"><span id="translatedtitle">The seesaw effect of <span class="hlt">winter</span> temperature change on the recruitment of cotton bollworms Helicoverpa armigera through mismatched phenology.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Reddy, Gadi V P; Shi, Peijian; Hui, Cang; Cheng, Xiaofei; Ouyang, Fang; Ge, Feng</p> <p>2015-12-01</p> <p>Knowing how climate change affects the population dynamics of insect pests is critical for the future of integrated pest management. Rising <span class="hlt">winter</span> temperatures from global <span class="hlt">warming</span> can drive increases in outbreaks of some agricultural pests. In contrast, here we propose an alternative hypothesis that both <span class="hlt">extremely</span> cold and <span class="hlt">warm</span> <span class="hlt">winters</span> can mismatch the timing between the eclosion of overwintering pests and the flowering of key host plants. As host plants normally need higher effective cumulative temperatures for flowering than insects need for eclosion, changes in flowering time will be less dramatic than changes in eclosion time, leading to a mismatch of phenology on either side of the optimal <span class="hlt">winter</span> temperature. We term this the "seesaw effect." Using a long-term dataset of the Old World cotton bollworm Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) in northern China, we tested this seesaw hypothesis by running a generalized additive model for the effects of the third generation moth in the preceding year, the <span class="hlt">winter</span> air temperature, the number of <span class="hlt">winter</span> days below a critical temperature and cumulative precipitation during <span class="hlt">winter</span> on the demography of the overwintering moth. Results confirmed the existence of the seesaw effect of <span class="hlt">winter</span> temperature change on overwintering populations. Pest management should therefore consider the indirect effect of changing crop phenology (whether due to greenhouse cultivation or to climate change) on pest outbreaks. As arthropods from mid- and high latitudes are actually living in a cooler thermal environment than their physiological optimum in contrast to species from lower latitudes, the effects of rising <span class="hlt">winter</span> temperatures on the population dynamics of arthropods in the different latitudinal zones should be considered separately. The seesaw effect makes it more difficult to predict the average long-term population dynamics of insect pests at high latitudes due to the potential sharp changes in annual growth rates</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=stomach&pg=7&id=ED167311','ERIC'); return false;" href="http://eric.ed.gov/?q=stomach&pg=7&id=ED167311"><span id="translatedtitle"><span class="hlt">Winter</span> Games.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Tarbuth, Lawson, Comp.</p> <p></p> <p>Educators may find activities for indoor and outdoor <span class="hlt">winter</span> programs in the games of the traditional Eskimo. These games are dominated by few-step operations and low level structural organization. For the most part they are quickly organized, begun, terminated, and ready to be recommenced. All types of games can be found, including quiet ones,…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=sky&pg=7&id=EJ987761','ERIC'); return false;" href="http://eric.ed.gov/?q=sky&pg=7&id=EJ987761"><span id="translatedtitle"><span class="hlt">Winter</span> Wonderlands</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Coy, Mary</p> <p>2011-01-01</p> <p>Listening to people complain about the hardships of <span class="hlt">winter</span> and the dreariness of the nearly constant gray sky prompted the author to help her sixth graders recognize and appreciate the beauty that surrounds them for nearly five months of the year in western New York. The author opines that if students could see things more artistically, the winter…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Battleships&pg=2&id=ED242456','ERIC'); return false;" href="http://eric.ed.gov/?q=Battleships&pg=2&id=ED242456"><span id="translatedtitle"><span class="hlt">Winter</span> Workshop.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Council of Outdoor Educators of Quebec, Montreal.</p> <p></p> <p>Materials on 11 topics presented at a <span class="hlt">winter</span> workshop for Quebec outdoor educators have been compiled into this booklet. Action story, instant replay, shoe factory, sound and action, and find an object to fit the description are described and recommended as group dynamic activities. Directions for five games (Superlative Selection; Data…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22351521','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22351521"><span id="translatedtitle">The state of the <span class="hlt">warm</span> and cold gas in the <span class="hlt">extreme</span> starburst at the core of the Phoenix galaxy cluster (SPT-CLJ2344-4243)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>McDonald, Michael; Bautz, Marshall W.; Swinbank, Mark; Edge, Alastair C.; Hogan, Michael T.; Wilner, David J.; Bayliss, Matthew B.; Veilleux, Sylvain; Benson, Bradford A.; Marrone, Daniel P.; McNamara, Brian R.; Wei, Lisa H.</p> <p>2014-03-20</p> <p>We present new optical integral field spectroscopy (Gemini South) and submillimeter spectroscopy (Submillimeter Array) of the central galaxy in the Phoenix cluster (SPT-CLJ2344-4243). This cluster was previously reported to have a massive starburst (∼800 M {sub ☉} yr{sup –1}) in the central, brightest cluster galaxy, most likely fueled by the rapidly cooling intracluster medium. These new data reveal a complex emission-line nebula, extending for >30 kpc from the central galaxy, detected at [O II]λλ3726, 3729, [O III]λλ4959, 5007, Hβ, Hγ, Hδ, [Ne III]λ3869, and He II λ4686. The total Hα luminosity, assuming Hα/Hβ = 2.85, is L {sub Hα} = 7.6 ± 0.4 ×10{sup 43} erg s{sup –1}, making this the most luminous emission-line nebula detected in the center of a cool core cluster. Overall, the relative fluxes of the low-ionization lines (e.g., [O II], Hβ) to the UV continuum are consistent with photoionization by young stars. In both the center of the galaxy and in a newly discovered highly ionized plume to the north of the galaxy, the ionization ratios are consistent with both shocks and active galactic nucleus (AGN) photoionization. We speculate that this extended plume may be a galactic wind, driven and partially photoionized by both the starburst and central AGN. Throughout the cluster we measure elevated high-ionization line ratios (e.g., He II/Hβ, [O III]/Hβ), coupled with an overall high-velocity width (FWHM ≳ 500 km s{sup –1}), suggesting that shocks are likely important throughout the interstellar medium of the central galaxy. These shocks are most likely driven by a combination of stellar winds from massive young stars, core-collapse supernovae, and the central AGN. In addition to the <span class="hlt">warm</span>, ionized gas, we detect a substantial amount of cold, molecular gas via the CO(3-2) transition, coincident in position with the galaxy center. We infer a molecular gas mass of M{sub H{sub 2}} = 2.2 ± 0.6 × 10{sup 10} M {sub ☉}, which implies that</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014ApJ...784...18M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014ApJ...784...18M"><span id="translatedtitle">The State of the <span class="hlt">Warm</span> and Cold Gas in the <span class="hlt">Extreme</span> Starburst at the Core of the Phoenix Galaxy Cluster (SPT-CLJ2344-4243)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>McDonald, Michael; Swinbank, Mark; Edge, Alastair C.; Wilner, David J.; Veilleux, Sylvain; Benson, Bradford A.; Hogan, Michael T.; Marrone, Daniel P.; McNamara, Brian R.; Wei, Lisa H.; Bayliss, Matthew B.; Bautz, Marshall W.</p> <p>2014-03-01</p> <p>We present new optical integral field spectroscopy (Gemini South) and submillimeter spectroscopy (Submillimeter Array) of the central galaxy in the Phoenix cluster (SPT-CLJ2344-4243). This cluster was previously reported to have a massive starburst (~800 M ⊙ yr-1) in the central, brightest cluster galaxy, most likely fueled by the rapidly cooling intracluster medium. These new data reveal a complex emission-line nebula, extending for >30 kpc from the central galaxy, detected at [O II]λλ3726, 3729, [O III]λλ4959, 5007, Hβ, Hγ, Hδ, [Ne III]λ3869, and He II λ4686. The total Hα luminosity, assuming Hα/Hβ = 2.85, is L Hα = 7.6 ± 0.4 ×1043 erg s-1, making this the most luminous emission-line nebula detected in the center of a cool core cluster. Overall, the relative fluxes of the low-ionization lines (e.g., [O II], Hβ) to the UV continuum are consistent with photoionization by young stars. In both the center of the galaxy and in a newly discovered highly ionized plume to the north of the galaxy, the ionization ratios are consistent with both shocks and active galactic nucleus (AGN) photoionization. We speculate that this extended plume may be a galactic wind, driven and partially photoionized by both the starburst and central AGN. Throughout the cluster we measure elevated high-ionization line ratios (e.g., He II/Hβ, [O III]/Hβ), coupled with an overall high-velocity width (FWHM gsim 500 km s-1), suggesting that shocks are likely important throughout the interstellar medium of the central galaxy. These shocks are most likely driven by a combination of stellar winds from massive young stars, core-collapse supernovae, and the central AGN. In addition to the <span class="hlt">warm</span>, ionized gas, we detect a substantial amount of cold, molecular gas via the CO(3-2) transition, coincident in position with the galaxy center. We infer a molecular gas mass of M_{H_2} = 2.2 ± 0.6 × 1010 M ⊙, which implies that the starburst will consume its fuel in ~30 Myr if it is not</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..12.9535J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..12.9535J"><span id="translatedtitle">Effects of <span class="hlt">extreme</span> spring temperatures on phenology: a case study from Munich and Ingolstadt</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jochner, Susanne; Menzel, Annette</p> <p>2010-05-01</p> <p><span class="hlt">Extreme</span> events - e.g. <span class="hlt">warm</span> spells or heavy precipitation events - are likely to increase in the future both in frequency and intensity. Therefore, research on <span class="hlt">extreme</span> events gains new importance; also in terms of plant development which is mostly triggered by temperatures. An arising question is how plants respond to an <span class="hlt">extreme</span> <span class="hlt">warm</span> spell when following an <span class="hlt">extreme</span> cold <span class="hlt">winter</span> season. This situation could be studied in spring 2009 in the greater area of Munich and Ingolstadt by phenological observations of flowering and leaf unfolding of birch (Betula pendula L.) and flowering of horse chestnut (Aesculus hippocastanum L.). The long chilling period of <span class="hlt">winter</span> 2008 and spring 2009 was followed by an immediate strong forcing of flowering and leaf unfolding, especially for birch. This <span class="hlt">extreme</span> weather situation diminished the difference between urban and rural dates of onset. Another important fact that could be observed in the proceeding period of December 2008 to April 2009 was the reduced temperature difference among urban and rural sites (urban heat island effect). Long-term observations (1951-2008) of the phenological network of the German Meteorological Service (DWD) were used to identify years with reduced urban-rural differences between onset times in the greater area of Munich in the past. Statistical analyses were conducted in order to answer the question whether the sequence of <span class="hlt">extreme</span> <span class="hlt">warm</span> and cold events leads to a decreased difference in phenological onset times or if this behaviour can be attributed to <span class="hlt">extreme</span> <span class="hlt">warm</span> springs themselves or to the decreased urban heat island effect which is mostly affected by general atmospheric circulation patterns.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20090009324&hterms=subsidence&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dsubsidence','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20090009324&hterms=subsidence&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dsubsidence"><span id="translatedtitle">Titan's <span class="hlt">Winter</span> Polar Vortex</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Flasar, F.M.; Achterberg, R.K.; Schinder, P.J.</p> <p>2008-01-01</p> <p>Titan's atmosphere has provided an interesting study in contrasts and similarities with Earth's. While both have N$_2$ as the dominant constituent and comparable surface pressures $\\sim1$ bar, Titan's next most abundant molecule is CH$_4$, not O$_2$, and the dissociative breakup of CH$_4$ and N$_2$ by sunlight and electron impact leads to a suite of hydrocarbons and nitriles, and ultimately the photochemical smog that enshrouds the moon. In addition, with a 15.95-day period, Titan is a slow rotator compared to Earth. While the mean zonal terrestrial winds are geostrophic, Titan's are mostly cyclostrophic, whipping around the moon in as little as 1 day. Despite the different dynamical regime, Titan's <span class="hlt">winter</span> stratosphere exhibits several characteristics that should be familiar to terrestrial meteorologists. The cold <span class="hlt">winter</span> pole near the 1 -mbar level is circumscribed by strong winds (up to 190 m/s) that act as a barrier to mixing with airmasses at lower latitudes. There is evidence of enhancement of several organic species over the <span class="hlt">winter</span> pole, indicating subsidence. The adiabatic heating associated with this subsidence gives rise to a <span class="hlt">warm</span> anomaly at the 0.01-mbar level, raising the stratopause two scale heights above its location at equatorial latitudes. Condensate ices have been detected in Titan's lower stratosphere within the <span class="hlt">winter</span> polar vortex from infrared spectra. Although not always unambiguously identified, their spatial distribution exhibits a sharp gradient, decreasing precipitously across the vortex away from the <span class="hlt">winter</span> pole. The interesting question of whether there is important heterogeneous chemistry occurring within the polar vortex, analogous to that occurring in the terrestrial polar stratospheric clouds in the ozone holes, has not been addressed. The breakup of Titan's <span class="hlt">winter</span> polar vortex has not yet been observed. On Earth, the polar vortex is nonlinearly disrupted by interaction with large-amplitude planetary waves. Large-scale waves have not</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ERL....11d4009K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ERL....11d4009K"><span id="translatedtitle">Physical characteristics of Eurasian <span class="hlt">winter</span> temperature variability</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kim, Kwang-Yul; Son, Seok-Woo</p> <p>2016-04-01</p> <p>Despite the on-going global <span class="hlt">warming</span>, recent <span class="hlt">winters</span> in Eurasian mid-latitudes were much colder than average. In an attempt to better understand the physical characteristics for cold Eurasian <span class="hlt">winters</span>, major sources of variability in surface air temperature (SAT) are investigated based on cyclostationary EOF analysis. The two leading modes of SAT variability represent the effect of Arctic amplification (AA) and the Arctic oscillation (AO), respectively. These two modes are distinct in terms of the physical characteristics, including surface energy fluxes and tropospheric circulations, and result in significantly different <span class="hlt">winter</span> SAT patterns over the Eurasian continent. The AA-related SAT anomalies are dipolar with <span class="hlt">warm</span> Arctic, centered at the Barents-Kara Seas, and cold East Asia. In contrast, the negative AO-related SAT anomalies are characterized by widespread cold anomalies in Northern Eurasia. Relative importance of the AA and the negative AO contributions to cold Eurasian <span class="hlt">winters</span> is sensitive to the region of interest.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26312211','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26312211"><span id="translatedtitle">Precipitation <span class="hlt">Extremes</span> Under 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>O'Gorman, Paul A</p> <p></p> <p>The response of precipitation <span class="hlt">extremes</span> to climate change is considered using results from theory, modeling, and observations, with a focus on the physical factors that control the response. Observations and simulations with climate models show that precipitation <span class="hlt">extremes</span> intensify in response to a <span class="hlt">warming</span> climate. However, the sensitivity of precipitation <span class="hlt">extremes</span> to <span class="hlt">warming</span> remains uncertain when convection is important, and it may be higher in the tropics than the extratropics. Several physical contributions govern the response of precipitation <span class="hlt">extremes</span>. The thermodynamic contribution is robust and well understood, but theoretical understanding of the microphysical and dynamical contributions is still being developed. Orographic precipitation <span class="hlt">extremes</span> and snowfall <span class="hlt">extremes</span> respond differently from other precipitation <span class="hlt">extremes</span> and require particular attention. Outstanding research challenges include the influence of mesoscale convective organization, the dependence on the duration considered, and the need to better constrain the sensitivity of tropical precipitation <span class="hlt">extremes</span> to <span class="hlt">warming</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=earth+AND+warming&pg=5&id=EJ484206','ERIC'); return false;" href="http://eric.ed.gov/?q=earth+AND+warming&pg=5&id=EJ484206"><span id="translatedtitle">Global <span class="hlt">Warming</span>?</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Eichman, Julia Christensen; Brown, Jeff A.</p> <p>1994-01-01</p> <p>Presents information and data on an experiment designed to test whether different atmosphere compositions are affected by light and temperature during both cooling and heating. Although flawed, the experiment should help students appreciate the difficulties that researchers face when trying to find evidence of global <span class="hlt">warming</span>. (PR)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21375534','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21375534"><span id="translatedtitle"><span class="hlt">Winter</span> leaf reddening in 'evergreen' species.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hughes, Nicole M</p> <p>2011-05-01</p> <p>Leaf reddening during autumn in senescing, deciduous tree species has received widespread attention from the public and in the scientific literature, whereas leaf reddening in evergreen species during <span class="hlt">winter</span> remains largely ignored. <span class="hlt">Winter</span> reddening can be observed in evergreen herbs, shrubs, vines and trees in Mediterranean, temperate, alpine, and arctic regions, and can persist for several months before dissipating with springtime <span class="hlt">warming</span>. Yet, little is known about the functional significance of this colour change, or why it occurs in some species but not others. Here, the biochemistry, physiology and ecology associated with <span class="hlt">winter</span> leaf reddening are reviewed, with special focus on its possible adaptive function. Photoprotection is currently the favoured hypothesis for <span class="hlt">winter</span> reddening, but alternative explanations have scarcely been explored. Intraspecific reddening generally increases with sunlight incidence, and may also accompany photosynthetic inferiority in photosynthetically 'weak' (e.g. low-nitrogen) individuals. Red leaves tend to show symptoms of shade acclimation relative to green, consistent with a photoprotective function. However, <span class="hlt">winter-red</span> and <span class="hlt">winter</span>-green species often cohabitate the same high-light environments, and exhibit similar photosynthetic capacities. The factors dictating interspecific <span class="hlt">winter</span> leaf colouration therefore remain unclear. Additional outstanding questions and future directions are also highlighted, and possible alternative functions of <span class="hlt">winter</span> reddening discussed.</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('http://adsabs.harvard.edu/abs/2016ThApC.126..519H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ThApC.126..519H"><span id="translatedtitle">Climate changes in temperature and precipitation <span class="hlt">extremes</span> in an alpine grassland of Central Asia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hu, Zengyun; Li, Qingxiang; Chen, Xi; Teng, Zhidong; Chen, Changchun; Yin, Gang; Zhang, Yuqing</p> <p>2016-11-01</p> <p>The natural ecosystem in Central Asia is sensitive and vulnerable to the arid and semiarid climate variations, especially the climate <span class="hlt">extreme</span> events. However, the climate <span class="hlt">extreme</span> events in this area are still unclear. Therefore, this study analyzed the climate variability in the temperature and precipitation <span class="hlt">extreme</span> events in an alpine grassland (Bayanbuluk) of Central Asia based on the daily minimum temperature, daily maximum temperature, and daily precipitation from 1958 to 2012. Statistically significant ( p < 0.01) increasing trends were found in the minimum temperature, maximum temperature at annual, and seasonal time scales except the <span class="hlt">winter</span> maximum temperature. In the seasonal changes, the <span class="hlt">winter</span> temperature had the largest contribution to the annual <span class="hlt">warming</span>. Further, there appeared increasing trends for the <span class="hlt">warm</span> nights and the <span class="hlt">warm</span> days and decreasing trends for the cool nights and the cool days at a 99 % confidence level. These trends directly resulted in an increasing trend for the growing season length (GSL) which could have positively influence on the vegetation productivity. For the precipitation, it displayed an increasing trend for the annual precipitation although it was not significant. And the summer precipitation had the same variations as the annual precipitation which indicated that the precipitation in summer made the biggest contribution to the annual precipitation than the other three seasons. The <span class="hlt">winter</span> precipitation had a significant increasing trend (1.49 mm/10a) and a decreasing trend was found in spring. We also found that the precipitation of the very wet days mainly contributes to the annual precipitation with the trend of 4.5 mm/10a. The maximum 1-day precipitation and the heavy precipitation days only had slight increasing trend. A sharp decreasing trend was found before the early 1980s, and then becoming increase for the above three precipitation indexes. The climate experienced a <span class="hlt">warm</span>-wet abrupt climate change in the 1980s</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1193634-microclimatic-performance-free-air-warming-co-enrichment-experiment-windy-wyoming-usa','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1193634-microclimatic-performance-free-air-warming-co-enrichment-experiment-windy-wyoming-usa"><span id="translatedtitle">Microclimatic performance of a free-air <span class="hlt">warming</span> and CO₂ enrichment experiment in windy Wyoming, USA</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>LeCain, Daniel; Smith, David; Morgan, Jack; ...</p> <p>2015-02-06</p> <p>In order to plan for global changing climate experiments are being conducted in many countries, but few have monitored the effects of the climate change treatments (<span class="hlt">warming</span>, elevated CO₂) on the experimental plot microclimate. During three years of an eight year study with year-round feedback-controlled infra-red heater <span class="hlt">warming</span> (1.5/3.0°C day/night) and growing season free-air CO₂ enrichment (600 ppm) in the mixed-grass prairie of Wyoming, USA, we monitored soil, leaf, canopy-air, above-canopy-air temperatures and relative humidity of control and treated experimental plots and evaluated ecologically important temperature differentials. Leaves were <span class="hlt">warmed</span> somewhat less than the target settings (1.1 & 1.5°C day/night)more » but soil was <span class="hlt">warmed</span> more creating an average that matched the target settings <span class="hlt">extremely</span> well both during the day and night plus the summer and <span class="hlt">winter</span>. The site typically has about 50% bare or litter covered soil, therefore soil heat transfer is more critical than in dense canopy ecosystems. The Wyoming site commonly has strong winds (5 ms⁻¹ average) and significant daily and seasonal temperature fluctuations (as much as 30°C daily) but the <span class="hlt">warming</span> system was nearly always able to maintain the set temperatures regardless of abiotic variation. The within canopy-air was only slightly <span class="hlt">warmed</span> and above canopy-air was not <span class="hlt">warmed</span> by the system, therefore convective <span class="hlt">warming</span> was minor. Elevated CO₂ had no direct effect nor interaction with the <span class="hlt">warming</span> treatment on microclimate. Relative humidity within the plant canopy was only slightly reduced by <span class="hlt">warming</span>. Soil water content was reduced by <span class="hlt">warming</span> but increased by elevated CO₂. This study demonstrates the importance of monitoring the microclimate in manipulative field global change experiments so that critical physiological and ecological conclusions can be determined. Highly variable energy demand fluctuations showed that passive IR heater <span class="hlt">warming</span> systems will not maintain desired <span class="hlt">warming</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1193634','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1193634"><span id="translatedtitle">Microclimatic performance of a free-air <span class="hlt">warming</span> and CO₂ enrichment experiment in windy Wyoming, USA</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>LeCain, Daniel; Smith, David; Morgan, Jack; Kimball, Bruce A.; Pendall, Elise; Miglietta, Franco; Liang, Wenju</p> <p>2015-02-06</p> <p>In order to plan for global changing climate experiments are being conducted in many countries, but few have monitored the effects of the climate change treatments (<span class="hlt">warming</span>, elevated CO₂) on the experimental plot microclimate. During three years of an eight year study with year-round feedback-controlled infra-red heater <span class="hlt">warming</span> (1.5/3.0°C day/night) and growing season free-air CO₂ enrichment (600 ppm) in the mixed-grass prairie of Wyoming, USA, we monitored soil, leaf, canopy-air, above-canopy-air temperatures and relative humidity of control and treated experimental plots and evaluated ecologically important temperature differentials. Leaves were <span class="hlt">warmed</span> somewhat less than the target settings (1.1 & 1.5°C day/night) but soil was <span class="hlt">warmed</span> more creating an average that matched the target settings <span class="hlt">extremely</span> well both during the day and night plus the summer and <span class="hlt">winter</span>. The site typically has about 50% bare or litter covered soil, therefore soil heat transfer is more critical than in dense canopy ecosystems. The Wyoming site commonly has strong winds (5 ms⁻¹ average) and significant daily and seasonal temperature fluctuations (as much as 30°C daily) but the <span class="hlt">warming</span> system was nearly always able to maintain the set temperatures regardless of abiotic variation. The within canopy-air was only slightly <span class="hlt">warmed</span> and above canopy-air was not <span class="hlt">warmed</span> by the system, therefore convective <span class="hlt">warming</span> was minor. Elevated CO₂ had no direct effect nor interaction with the <span class="hlt">warming</span> treatment on microclimate. Relative humidity within the plant canopy was only slightly reduced by <span class="hlt">warming</span>. Soil water content was reduced by <span class="hlt">warming</span> but increased by elevated CO₂. This study demonstrates the importance of monitoring the microclimate in manipulative field global change experiments so that critical physiological and ecological conclusions can be determined. Highly variable energy demand fluctuations showed that passive IR heater <span class="hlt">warming</span> systems will not maintain desired <span class="hlt">warming</span> for much</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.6155V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.6155V"><span id="translatedtitle">Influence of spatial and temporal scales in identifying temperature <span class="hlt">extremes</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>van Eck, Christel M.; Friedlingstein, Pierre; Mulder, Vera L.; Regnier, Pierre A. G.</p> <p>2016-04-01</p> <p><span class="hlt">Extreme</span> heat events are becoming more frequent. Notable are severe heatwaves such as the European heatwave of 2003, the Russian heat wave of 2010 and the Australian heatwave of 2013. Surface temperature is attaining new maxima not only during the summer but also during the <span class="hlt">winter</span>. The year of 2015 is reported to be a temperature record breaking year for both summer and <span class="hlt">winter</span>. These <span class="hlt">extreme</span> temperatures are taking their human and environmental toll, emphasizing the need for an accurate method to define a heat <span class="hlt">extreme</span> in order to fully understand the spatial and temporal spread of an <span class="hlt">extreme</span> and its impact. This research aims to explore how the use of different spatial and temporal scales influences the identification of a heat <span class="hlt">extreme</span>. For this purpose, two near-surface temperature datasets of different temporal scale and spatial scale are being used. First, the daily ERA-Interim dataset of 0.25 degree and a time span of 32 years (1979-2010). Second, the daily Princeton Meteorological Forcing Dataset of 0.5 degree and a time span of 63 years (1948-2010). A temperature is considered <span class="hlt">extreme</span> anomalous when it is surpassing the 90th, 95th, or the 99th percentile threshold based on the aforementioned pre-processed datasets. The analysis is conducted on a global scale, dividing the world in IPCC's so-called SREX regions developed for the analysis of <span class="hlt">extreme</span> climate events. Pre-processing is done by detrending and/or subtracting the monthly climatology based on 32 years of data for both datasets and on 63 years of data for only the Princeton Meteorological Forcing Dataset. This results in 6 datasets of temperature anomalies from which the location in time and space of the anomalous <span class="hlt">warm</span> days are identified. Comparison of the differences between these 6 datasets in terms of absolute threshold temperatures for <span class="hlt">extremes</span> and the temporal and spatial spread of the <span class="hlt">extreme</span> anomalous <span class="hlt">warm</span> days show a dependence of the results on the datasets and methodology used. This stresses</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=greenhouse+AND+effect+AND+helps&pg=2&id=EJ502198','ERIC'); return false;" href="http://eric.ed.gov/?q=greenhouse+AND+effect+AND+helps&pg=2&id=EJ502198"><span id="translatedtitle">Global <span class="hlt">Warming</span>: Understanding and Teaching the Forecast.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Andrews, Bill</p> <p>1995-01-01</p> <p>A resource for teaching about the consequences of global <span class="hlt">warming</span>. Discusses feedback from the temperature increase, changes in the global precipitation pattern, effects on agriculture, weather <span class="hlt">extremes</span>, effects on forests, effects on biodiversity, effects on sea levels, and actions which will help the global community cope with global <span class="hlt">warming</span>. (LZ)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/publication/?seqNo115=276422','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/publication/?seqNo115=276422"><span id="translatedtitle">Duration of prepupal summer dormancy regulates synchronization of adult diapause with <span class="hlt">winter</span> temperatures in bees of the genus Osmia</span></a></p> <p><a target="_blank" href="http://www.ars.usda.gov/services/TekTran.htm">Technology Transfer Automated Retrieval System (TEKTRAN)</a></p> <p></p> <p></p> <p>Osmia (Osmia) bees are strictly univoltine and <span class="hlt">winter</span> as diapausing adults. In these species, the timing of adult eclosion with the onset of <span class="hlt">wintering</span> conditions is critical, because adults exposed to long pre-<span class="hlt">wintering</span> periods show increased lipid loss and <span class="hlt">winter</span> mortality. Populations from <span class="hlt">warm</span> ar...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatCC...6..627S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatCC...6..627S"><span id="translatedtitle">Human influence on climate in the 2014 southern England <span class="hlt">winter</span> floods and their impacts</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schaller, Nathalie; Kay, Alison L.; Lamb, Rob; Massey, Neil R.; van Oldenborgh, Geert Jan; Otto, Friederike E. L.; Sparrow, Sarah N.; Vautard, Robert; Yiou, Pascal; Ashpole, Ian; Bowery, Andy; Crooks, Susan M.; Haustein, Karsten; Huntingford, Chris; Ingram, William J.; Jones, Richard G.; Legg, Tim; Miller, Jonathan; Skeggs, Jessica; Wallom, David; Weisheimer, Antje; Wilson, Simon; Stott, Peter A.; Allen, Myles R.</p> <p>2016-06-01</p> <p>A succession of storms reaching southern England in the <span class="hlt">winter</span> of 2013/2014 caused severe floods and #451 million insured losses. In a large ensemble of climate model simulations, we find that, as well as increasing the amount of moisture the atmosphere can hold, anthropogenic <span class="hlt">warming</span> caused a small but significant increase in the number of January days with westerly flow, both of which increased <span class="hlt">extreme</span> precipitation. Hydrological modelling indicates this increased <span class="hlt">extreme</span> 30-day-average Thames river flows, and slightly increased daily peak flows, consistent with the understanding of the catchment’s sensitivity to longer-duration precipitation and changes in the role of snowmelt. Consequently, flood risk mapping shows a small increase in properties in the Thames catchment potentially at risk of riverine flooding, with a substantial range of uncertainty, demonstrating the importance of explicit modelling of impacts and relatively subtle changes in weather-related risks when quantifying present-day effects of human influence on climate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25490555','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25490555"><span id="translatedtitle">Could behaviour and not physiological thermal tolerance determine <span class="hlt">winter</span> survival of aphids in cereal fields?</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Alford, Lucy; Andrade, Thiago Oliveira; Georges, Romain; Burel, Françoise; van Baaren, Joan</p> <p>2014-01-01</p> <p>Traits of physiological thermotolerance are commonly measured in the laboratory as predictors of the field success of ectotherms at unfavourable temperatures (e.g. during harsh <span class="hlt">winters</span>, heatwaves, or under conditions of predicted global <span class="hlt">warming</span>). Due to being more complicated to measure, behavioural thermoregulation is less commonly studied, although both physiology and behaviour interact to explain the survival of ectotherms. The aphids Metopolophium dirhodum, Rhopalosiphum padi and Sitobion avenae are commercially important pests of temperate cereal crops. Although coexisting, these species markedly differ in <span class="hlt">winter</span> success, with R. padi being the most abundant species during cold <span class="hlt">winters</span>, followed by S. avenae and lastly M. dirhodum. To better understand the thermal physiology and behavioural factors contributing to differential <span class="hlt">winter</span> success, the lethal temperature (physiological thermotolerance) and the behaviour of aphids in a declining temperature regime (behavioural thermotolerance) of these three species were investigated. Physiological thermotolerance significantly differed between the three species, with R. padi consistently the least cold tolerant and S. avenae the most cold tolerant. However, although the least cold tolerant of the study species, significantly more R. padi remained attached to the host plant at <span class="hlt">extreme</span> sub-zero temperatures than S. avenae and M. dirhodum. Given the success of anholocyclic R. padi in harsh <span class="hlt">winters</span> compared to its anholocyclic counterparts, this study illustrates that behavioural differences could be more important than physiological thermotolerance in explaining resistance to <span class="hlt">extreme</span> temperatures. Furthermore it highlights that there is a danger to studying physiological thermotolerance in isolation when ascertaining risks of ectotherm invasions, the establishment potential of exotic species in glasshouses, or predicting species impacts under climate change scenarios.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003EAEJA.....7519V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003EAEJA.....7519V"><span id="translatedtitle"><span class="hlt">Warm</span> Storms Associated with Avalanches Hazard and Floods in the Andes Mountains</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vergara, J.</p> <p>2003-04-01</p> <p>Rain-on-snow events produce avalanches of different magnitude depending on the snowpack properties, air temperatures and rain intensities. <span class="hlt">Winter</span> storms in this mountain range typically have rain/snow levels between 1000 and 2200 m. above sea level, but <span class="hlt">warm</span> storms with higher rain/snow of to 3000 m. above sea level. occur in <span class="hlt">extreme</span> <span class="hlt">winters</span> and have the potential to generate rain on snow floods and wet-snow avalanches. For example, the flood of June 29 of 2000 occurred after one of <span class="hlt">extremely</span> wet June of the last 40 years were snowfall was 991cm in the Aconcagua Valley. Infrequently storms activity generated a huge snowfall and rainfall over the Andes mountains on June of 2000 (1525mm in El Maule Valley) and the end of the unusually period, the flood was triggered by rising temperatures on the mountains and heavy rain (199mm in 24 hours) fall over the fresh snow on the morning of June 29 and floods wave developed and moved down along of the all river located on Central part of Chile, the foods peak was 2970.5m3/s on the El Maule basin in the morning of June 29. This paper studies the characteristics of <span class="hlt">warm</span> storms the had the potential to generate wet-snow avalanches and floods.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017APJAS..53...31L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017APJAS..53...31L"><span id="translatedtitle">Future trend in seasonal lengths and <span class="hlt">extreme</span> temperature distributions over South Korea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lee, Jangho</p> <p>2017-02-01</p> <p>CSEOF analysis is conducted on the daily mean, maximum, and minimum temperatures measured at 60 Korea Meteorological Administration stations in the period of 1979-2014. Each PC time series is detrended and fitted to an autoregressive (AR) model. The resulting AR models are used to generate 100 sets of synthetic PC time series for the period of 1979-2064, and the linear trends are added back to the resulting PC time series. Then, 100 sets of synthetic daily temperatures are produced by using the synthetic PC time series together with the The cyclostationary EOF (CSEOF) loading vectors. The statistics of the synthetic daily temperatures are similar to those of the original data during the observational period (1979-2064). Based on the synthetic datasets, future statistics including distribution of <span class="hlt">extreme</span> temperatures and the length of four seasons have been analyzed. Average daily temperature in spring is expected to decrease by a small amount, whereas average temperatures in summer, fall and <span class="hlt">winter</span> are expected to increase. Standard deviation of daily temperatures is expected to increase in all four seasons. The Generalized <span class="hlt">Extreme</span> Value and Generalized Pareto distributions of <span class="hlt">extreme</span> temperatures indicate that both <span class="hlt">warm</span> and cold <span class="hlt">extremes</span> are likely to increase in summer, while only <span class="hlt">warm</span> <span class="hlt">extremes</span> are predicted to increase significantly in <span class="hlt">winter</span>. Thus, heat waves will increase and cold waves will decrease in number in future. Spring and fall will be shorter, whereas summer and <span class="hlt">winter</span> will be longer. A statistical prediction carried out in the present study may serve as a baseline solution for numerical predictions using complex models.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ClDy...44.1187B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ClDy...44.1187B"><span id="translatedtitle">A record-breaking low ice cover over the Great Lakes during <span class="hlt">winter</span> 2011/2012: combined effects of a strong positive NAO and La Niña</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bai, Xuezhi; Wang, Jia; Austin, Jay; Schwab, David J.; Assel, Raymond; Clites, Anne; Bratton, John F.; Colton, Marie; Lenters, John; Lofgren, Brent; Wohlleben, Trudy; Helfrich, Sean; Vanderploeg, Henry; Luo, Lin; Leshkevich, George</p> <p>2015-03-01</p> <p>A record-breaking low ice cover occurred in the North American Great Lakes during <span class="hlt">winter</span> 2011/2012, in conjunction with a strong positive Arctic Oscillation/North Atlantic Oscillation (+AO/NAO) and a La Niña event. Large-scale atmosphere circulation in the Pacific/North America (PNA) region reflected a combined signal of La Niña and +NAO. Surface heat flux analysis shows that sensible heat flux contributed most to the net surface heat flux anomaly. Surface air temperature is the dominant factor governing the interannual variability of Great Lakes ice cover. Neither La Niña nor +NAO alone can be responsible for the <span class="hlt">extreme</span> warmth; the typical mid-latitude response to La Niña events is a negative PNA pattern, which does not have a significant impact on Great Lakes <span class="hlt">winter</span> climate; the positive phase of NAO is usually associated with moderate <span class="hlt">warming</span>. When the two occurred simultaneously, the combined effects of La Niña and +NAO resulted in a negative East Pacific pattern with a negative center over Alaska/Western Canada, a positive center in the eastern North Pacific (north of Hawaii), and an enhanced positive center over the eastern and southern United States. The overall pattern prohibited the movement of the Arctic air mass into mid-latitudes and enhanced southerly flow and <span class="hlt">warm</span> advection from the Gulf of Mexico over the eastern United States and Great Lakes region, leading to the record-breaking low ice cover. It is another climatic pattern that can induce <span class="hlt">extreme</span> <span class="hlt">warming</span> in the Great Lakes region in addition to strong El Niño events. A very similar event occurred in the <span class="hlt">winter</span> of 1999/2000. This <span class="hlt">extreme</span> <span class="hlt">warm</span> <span class="hlt">winter</span> and spring in 2012 had significant impacts on the physical environment, as well as counterintuitive effects on phytoplankton abundance.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003GeoRL..30.1583W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003GeoRL..30.1583W"><span id="translatedtitle">Dynamical control of NH and SH <span class="hlt">winter</span>/spring total ozone from GOME observations in 1995-2002</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Weber, M.; Dhomse, S.; Wittrock, F.; Richter, A.; Sinnhuber, B.-M.; Burrows, J. P.</p> <p>2003-06-01</p> <p>The abnormal high wave activity in austral spring 2002 led to the first observation of a major stratospheric <span class="hlt">warming</span> in the southern hemisphere resulting in a net <span class="hlt">winter</span> increase of mid- to high latitude total ozone until September 2002. In previous years chemical ozone depletion inside the Antarctic vortex was sufficiently high to reduce mean total ozone south of 50° in September to values slightly below that of March (fall) as observed by GOME during the period 1995-2001. This unusual event permits us to examine the interannual variability in total ozone and OClO (the latter being an indicator of the level of chlorine activation inside the polar vortex) as measured by GOME combining data from the southern and northern hemisphere. It is shown that the absolute <span class="hlt">winter</span> eddy heat flux between 43° and 70° latitudes at 100 hPa correlates <span class="hlt">extremely</span> well (r = 0.97) with spring-to-fall ratio of total ozone polewards of 50° and anti-correlates with the <span class="hlt">winter</span> integrated maximum OClO column amounts (r = -0.94) using this combined data set. The unusual ozone ratio for austral <span class="hlt">winter</span>/spring 2002 lies almost midway between typical values for Antarctica and those for recent cold Arctic <span class="hlt">winter</span>/spring seasons.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ThApC.124..855Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ThApC.124..855Z"><span id="translatedtitle">Spatiotemporal variations of temperature and precipitation <span class="hlt">extremes</span> in the Poyang Lake basin, China</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Qiang; Xiao, Mingzhong; Singh, Vijay P.; Wang, Yeqiao</p> <p>2016-05-01</p> <p>Daily temperature and precipitation data from 15 rain gauges covering a period of 1957-2011 were analyzed using the Mann-Kendall trend test with the aim to investigate changing characteristics of weather <span class="hlt">extremes</span> in the Poyang Lake basin, the largest freshwater lake in China. Also, the connection between El Niño Southern Oscillation (ENSO) and precipitation <span class="hlt">extremes</span> is analyzed and possible causes for the connection are briefly discussed. Results indicate that (1) <span class="hlt">warming</span>, characterized by a decreasing trend in frost days and a significant decrease of temperature <span class="hlt">extremes</span> defined by lower temperature, in the Poyang Lake basin is observed. Temperature <span class="hlt">extremes</span>, defined by higher temperature indices such as hot days, exhibit moderate changes with no significant trends. Moreover, <span class="hlt">warming</span> occurs mainly in the northern part of the Poyang Lake basin; (2) precipitation changes are intensifying as reflected by increasing precipitation <span class="hlt">extremes</span>. However, these changes are different from 1 month to another and the intensification is found mainly in <span class="hlt">winter</span> and/or summer months; (3) the influence of ENSO on precipitation changes in the Poyang Lake basin is evident with a time lag of longer than 3 months. This should be due to the fact that higher sea surface temperature tends to trigger the occurrence of convective precipitation regimes. Results of this study are important for modeling the occurrence of precipitation <span class="hlt">extremes</span> in a changing climate and regional climatic responses to global climate changes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4493696','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4493696"><span id="translatedtitle">Photosynthetic response of Persian Gulf acroporid corals to summer versus <span class="hlt">winter</span> temperature deviations</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Saleh, Abolfazl; Mehdinia, Ali; Shirvani, Arash; Kayal, Mohsen</p> <p>2015-01-01</p> <p>With on-going climate change, coral susceptibility to thermal stress constitutes a central concern in reefconservation. In the Persian Gulf, coral reefs are confronted with a high seasonal variability in water temperature, and both hot and cold <span class="hlt">extremes</span> have been associated with episodes of coral bleaching and mortality. Using physiological performance as a measure of coral health, we investigated the thermal susceptibility of the common acroporid, Acropora downingi, near Hengam Island where the temperature oscillates seasonally in the range 20.2–34.2 °C. In a series of two short-term experiments comparing coral response in summer versus <span class="hlt">winter</span> conditions, we exposed corals during each season (1) to the corresponding seasonal average and <span class="hlt">extreme</span> temperature levels in a static thermal environment, and (2) to a progressive temperature deviation from the annual mean toward the corresponding <span class="hlt">extreme</span> seasonal value and beyond in a dynamic thermal environment. We monitored four indictors of coral physiological performance: net photosynthesis (Pn), dark respiration (R), autotrophic capability (Pn/R), and survival. Corals exposed to <span class="hlt">warming</span> during summer showed a decrease in net photosynthesis and ultimately died, while corals exposed to cooling during <span class="hlt">winter</span> were not affected in their photosynthetic performance and survival. Coral autotrophic capability Pn/R was lower at the warmer thermal level within eachseason, and during summer compared to <span class="hlt">winter</span>. Corals exposed to the maximum temperature of summer displayed Pn/R < 1, inferring that photosynthetic performance could not support basal metabolic needs under this environment. Our results suggest that the autotrophic performance of the Persian Gulf A. downingi is sensitive to the <span class="hlt">extreme</span> temperatures endured in summer, and therefore its populations may be impacted by future increases in water temperature. PMID:26157627</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1814288C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1814288C"><span id="translatedtitle">How <span class="hlt">extreme</span> are <span class="hlt">extremes</span>?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cucchi, Marco; Petitta, Marcello; Calmanti, Sandro</p> <p>2016-04-01</p> <p>High temperatures have an impact on the energy balance of any living organism and on the operational capabilities of critical infrastructures. Heat-wave indicators have been mainly developed with the aim of capturing the potential impacts on specific sectors (agriculture, health, wildfires, transport, power generation and distribution). However, the ability to capture the occurrence of <span class="hlt">extreme</span> temperature events is an essential property of a multi-hazard <span class="hlt">extreme</span> climate indicator. Aim of this study is to develop a standardized heat-wave indicator, that can be combined with other indices in order to describe multiple hazards in a single indicator. The proposed approach can be used in order to have a quantified indicator of the strenght of a certain <span class="hlt">extreme</span>. As a matter of fact, <span class="hlt">extremes</span> are usually distributed in exponential or exponential-exponential functions and it is difficult to quickly asses how strong was an <span class="hlt">extreme</span> events considering only its magnitude. The proposed approach simplify the quantitative and qualitative communication of <span class="hlt">extreme</span> magnitude</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AtmRe.185..131Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AtmRe.185..131Z"><span id="translatedtitle">Spatiotemporal variability of <span class="hlt">extreme</span> temperature frequency and amplitude 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>Zhang, Yuanjie; Gao, Zhiqiu; Pan, Zaitao; Li, Dan; Huang, Xinhui</p> <p>2017-03-01</p> <p>Temperature <span class="hlt">extremes</span> in China are examined based on daily maximum and minimum temperatures from station observations and multiple global climate models. The magnitude and frequency of <span class="hlt">extremes</span> are expressed in terms of return values and periods, respectively, estimated by the fitted Generalized <span class="hlt">Extreme</span> Value (GEV) distribution of annual <span class="hlt">extreme</span> temperatures. The observations suggest that changes in temperature <span class="hlt">extremes</span> considerably exceed changes in the respective climatological means during the past five decades, with greater amplitude of increases in cold <span class="hlt">extremes</span> than in <span class="hlt">warm</span> <span class="hlt">extremes</span>. The frequency of <span class="hlt">warm</span> (cold) <span class="hlt">extremes</span> increases (decreases) over most areas, with an increasingly faster rate as the <span class="hlt">extremity</span> level rises. Changes in <span class="hlt">warm</span> <span class="hlt">extremes</span> are more dependent on the varying shape of GEV distribution than the location shift, whereas changes in cold <span class="hlt">extremes</span> are more closely associated with the location shift. The models simulate the overall pattern of temperature <span class="hlt">extremes</span> during 1961-1981 reasonably well in China, but they show a smaller asymmetry between changes in <span class="hlt">warm</span> and cold <span class="hlt">extremes</span> primarily due to their underestimation of increases in cold <span class="hlt">extremes</span> especially over southern China. Projections from a high emission scenario show the multi-model median change in <span class="hlt">warm</span> and cold <span class="hlt">extremes</span> by 2040 relative to 1971 will be 2.6 °C and 2.8 °C, respectively, with the strongest changes in cold <span class="hlt">extremes</span> shifting southward. By 2040, <span class="hlt">warm</span> <span class="hlt">extremes</span> at the 1971 20-year return values would occur about every three years, while the 1971 cold <span class="hlt">extremes</span> would occur once in > 500 years.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003AGUFM.H22B0919L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003AGUFM.H22B0919L"><span id="translatedtitle">Long-Term <span class="hlt">Warm</span>-Season Stream Temperature Variations and Changes Over Siberian Lena River</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, B.; Yang, D.</p> <p>2003-12-01</p> <p>Stream temperature is an important environmental variable that has considerable significance in regional hydrology, climate, and ecology systems. Few investigations on long-term stream temperature variations in Arctic regions have been undertaken. This research examined and analyzed long-term (1950-1992) stream temperature data collected at dozens of stations in the Lena River basin during (open water) <span class="hlt">warm</span> seasons. Preliminary results show that: (1) the stream temperature across the whole basin shows a significant positive trend during early <span class="hlt">warm</span> season, which may indicate a response of early snowmelt due to climate <span class="hlt">warming</span> in the <span class="hlt">winter</span> and spring seasons; (2) over the Aldan tributary, stream temperatures collected at elevated locations are much lower than those at low valley stations; (3) in the Upper Lena river, stream temperatures have very strong negative trend in late July to early August, which imply certain climatic factors is affecting the stream temperature regime during this period; and, (4) in the Vilui subbasin, stream temperatures are strongly affected by reservoir regulations, for instance, <span class="hlt">extremely</span> strong positive and negative trends appear at the station close to reservoir in early and middle <span class="hlt">warm</span> season, respectively. The research has defined stream temperature regime and identified its long-term changes/variations over Lena river basin. Our future work will examine the impacts of climate change on river thermal condition. We will also study the effects of local environmental settings to stream temperatures and aquatic life.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20039819','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20039819"><span id="translatedtitle">The impact of global <span class="hlt">warming</span> on Mount Everest.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Moore, G W K; Semple, John L</p> <p>2009-01-01</p> <p>Global <span class="hlt">warming</span> impacts a wide range of human activities and ecosystems. One unanticipated consequence of the <span class="hlt">warming</span> is an increase in barometric pressure throughout the troposphere. Mount Everest's <span class="hlt">extreme</span> height and resulting low barometric pressure places humans near its summit in an <span class="hlt">extreme</span> state of hypoxia. Here we quantify the degree with which this <span class="hlt">warming</span> is increasing the barometric pressure near Everest's summit and argue that it is of such a magnitude as to make the mountain, over time, easier to climb.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24691026','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24691026"><span id="translatedtitle"><span class="hlt">Winter</span> climate limits subantarctic low forest growth and establishment.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Harsch, Melanie A; McGlone, Matt S; Wilmshurst, Janet M</p> <p>2014-01-01</p> <p>Campbell Island, an isolated island 600 km south of New Zealand mainland (52 °S, 169 °E) is oceanic (Conrad Index of Continentality  =  -5) with small differences between mean summer and <span class="hlt">winter</span> temperatures. Previous work established the unexpected result that a mean annual climate <span class="hlt">warming</span> of c. 0.6 °C since the 1940's has not led to upward movement of the forest limit. Here we explore the relative importance of summer and <span class="hlt">winter</span> climatic conditions on growth and age-class structure of the treeline forming species, Dracophyllum longifolium and Dracophyllum scoparium over the second half of the 20th century. The relationship between climate and growth and establishment were evaluated using standard dendroecological methods and local climate data from a meteorological station on the island. Growth and establishment were correlated against climate variables and further evaluated within hierarchical regression models to take into account the effect of plot level variables. <span class="hlt">Winter</span> climatic conditions exerted a greater effect on growth and establishment than summer climatic conditions. Establishment is maximized under <span class="hlt">warm</span> (mean <span class="hlt">winter</span> temperatures >7 °C), dry <span class="hlt">winters</span> (total <span class="hlt">winter</span> precipitation <400 mm). Growth, on the other hand, is adversely affected by wide <span class="hlt">winter</span> temperature ranges and increased rainfall. The contrasting effect of <span class="hlt">winter</span> warmth on growth and establishment suggests that <span class="hlt">winter</span> temperature affects growth and establishment through differing mechanisms. We propose that milder <span class="hlt">winters</span> enhance survival of seedlings and, therefore, recruitment, but increases metabolic stress on established plants, resulting in lower growth rates. Future <span class="hlt">winter</span> <span class="hlt">warming</span> may therefore have complex effects on plant growth and establishment globally.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3972215','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3972215"><span id="translatedtitle"><span class="hlt">Winter</span> Climate Limits Subantarctic Low Forest Growth and Establishment</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Harsch, Melanie A.; McGlone, Matt S.; Wilmshurst, Janet M.</p> <p>2014-01-01</p> <p>Campbell Island, an isolated island 600 km south of New Zealand mainland (52°S, 169°E) is oceanic (Conrad Index of Continentality  = −5) with small differences between mean summer and <span class="hlt">winter</span> temperatures. Previous work established the unexpected result that a mean annual climate <span class="hlt">warming</span> of c. 0.6°C since the 1940's has not led to upward movement of the forest limit. Here we explore the relative importance of summer and <span class="hlt">winter</span> climatic conditions on growth and age-class structure of the treeline forming species, Dracophyllum longifolium and Dracophyllum scoparium over the second half of the 20th century. The relationship between climate and growth and establishment were evaluated using standard dendroecological methods and local climate data from a meteorological station on the island. Growth and establishment were correlated against climate variables and further evaluated within hierarchical regression models to take into account the effect of plot level variables. <span class="hlt">Winter</span> climatic conditions exerted a greater effect on growth and establishment than summer climatic conditions. Establishment is maximized under <span class="hlt">warm</span> (mean <span class="hlt">winter</span> temperatures >7 °C), dry <span class="hlt">winters</span> (total <span class="hlt">winter</span> precipitation <400 mm). Growth, on the other hand, is adversely affected by wide <span class="hlt">winter</span> temperature ranges and increased rainfall. The contrasting effect of <span class="hlt">winter</span> warmth on growth and establishment suggests that <span class="hlt">winter</span> temperature affects growth and establishment through differing mechanisms. We propose that milder <span class="hlt">winters</span> enhance survival of seedlings and, therefore, recruitment, but increases metabolic stress on established plants, resulting in lower growth rates. Future <span class="hlt">winter</span> <span class="hlt">warming</span> may therefore have complex effects on plant growth and establishment globally. PMID:24691026</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://files.eric.ed.gov/fulltext/EJ218337.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/EJ218337.pdf"><span id="translatedtitle">A <span class="hlt">Winter</span> Survival Unit.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Phillips, Ronald E.</p> <p>1979-01-01</p> <p>The article is a condensation of materials from the <span class="hlt">winter</span> survival unit of a Canadian snow ecology course. The unit covers: cold physiology, frostbite, snowblindness, hypothermia, <span class="hlt">winter</span> campout, and survival strategies. (SB)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://medlineplus.gov/winterweatheremergencies.html','NIH-MEDLINEPLUS'); return false;" href="https://medlineplus.gov/winterweatheremergencies.html"><span id="translatedtitle"><span class="hlt">Winter</span> Weather Emergencies</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>Severe <span class="hlt">winter</span> weather can lead to health and safety challenges. You may have to cope with Cold related health problems, including ... there are no guarantees of safety during <span class="hlt">winter</span> weather emergencies, you can take actions to protect yourself. ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25658313','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25658313"><span id="translatedtitle">Microclimatic performance of a free-air <span class="hlt">warming</span> and CO2 enrichment experiment in windy Wyoming, USA.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>LeCain, Daniel; Smith, David; Morgan, Jack; Kimball, Bruce A; Pendall, Elise; Miglietta, Franco</p> <p>2015-01-01</p> <p>In order to plan for global changing climate experiments are being conducted in many countries, but few have monitored the effects of the climate change treatments (<span class="hlt">warming</span>, elevated CO2) on the experimental plot microclimate. During three years of an eight year study with year-round feedback-controlled infra-red heater <span class="hlt">warming</span> (1.5/3.0°C day/night) and growing season free-air CO2 enrichment (600 ppm) in the mixed-grass prairie of Wyoming, USA, we monitored soil, leaf, canopy-air, above-canopy-air temperatures and relative humidity of control and treated experimental plots and evaluated ecologically important temperature differentials. Leaves were <span class="hlt">warmed</span> somewhat less than the target settings (1.1 & 1.5°C day/night) but soil was <span class="hlt">warmed</span> more creating an average that matched the target settings <span class="hlt">extremely</span> well both during the day and night plus the summer and <span class="hlt">winter</span>. The site typically has about 50% bare or litter covered soil, therefore soil heat transfer is more critical than in dense canopy ecosystems. The Wyoming site commonly has strong winds (5 ms(-1) average) and significant daily and seasonal temperature fluctuations (as much as 30°C daily) but the <span class="hlt">warming</span> system was nearly always able to maintain the set temperatures regardless of abiotic variation. The within canopy-air was only slightly <span class="hlt">warmed</span> and above canopy-air was not <span class="hlt">warmed</span> by the system, therefore convective <span class="hlt">warming</span> was minor. Elevated CO2 had no direct effect nor interaction with the <span class="hlt">warming</span> treatment on microclimate. Relative humidity within the plant canopy was only slightly reduced by <span class="hlt">warming</span>. Soil water content was reduced by <span class="hlt">warming</span> but increased by elevated CO2. This study demonstrates the importance of monitoring the microclimate in manipulative field global change experiments so that critical physiological and ecological conclusions can be determined. Highly variable energy demand fluctuations showed that passive IR heater <span class="hlt">warming</span> systems will not maintain desired <span class="hlt">warming</span> for much of the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4319967','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4319967"><span id="translatedtitle">Microclimatic Performance of a Free-Air <span class="hlt">Warming</span> and CO2 Enrichment Experiment in Windy Wyoming, USA</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>LeCain, Daniel; Smith, David; Morgan, Jack; Kimball, Bruce A.; Pendall, Elise; Miglietta, Franco</p> <p>2015-01-01</p> <p>In order to plan for global changing climate experiments are being conducted in many countries, but few have monitored the effects of the climate change treatments (<span class="hlt">warming</span>, elevated CO2) on the experimental plot microclimate. During three years of an eight year study with year-round feedback-controlled infra-red heater <span class="hlt">warming</span> (1.5/3.0°C day/night) and growing season free-air CO2 enrichment (600 ppm) in the mixed-grass prairie of Wyoming, USA, we monitored soil, leaf, canopy-air, above-canopy-air temperatures and relative humidity of control and treated experimental plots and evaluated ecologically important temperature differentials. Leaves were <span class="hlt">warmed</span> somewhat less than the target settings (1.1 & 1.5°C day/night) but soil was <span class="hlt">warmed</span> more creating an average that matched the target settings <span class="hlt">extremely</span> well both during the day and night plus the summer and <span class="hlt">winter</span>. The site typically has about 50% bare or litter covered soil, therefore soil heat transfer is more critical than in dense canopy ecosystems. The Wyoming site commonly has strong winds (5 ms-1 average) and significant daily and seasonal temperature fluctuations (as much as 30°C daily) but the <span class="hlt">warming</span> system was nearly always able to maintain the set temperatures regardless of abiotic variation. The within canopy-air was only slightly <span class="hlt">warmed</span> and above canopy-air was not <span class="hlt">warmed</span> by the system, therefore convective <span class="hlt">warming</span> was minor. Elevated CO2 had no direct effect nor interaction with the <span class="hlt">warming</span> treatment on microclimate. Relative humidity within the plant canopy was only slightly reduced by <span class="hlt">warming</span>. Soil water content was reduced by <span class="hlt">warming</span> but increased by elevated CO2. This study demonstrates the importance of monitoring the microclimate in manipulative field global change experiments so that critical physiological and ecological conclusions can be determined. Highly variable energy demand fluctuations showed that passive IR heater <span class="hlt">warming</span> systems will not maintain desired <span class="hlt">warming</span> for much of the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28219258','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28219258"><span id="translatedtitle">Competent and <span class="hlt">Warm</span>?</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hansen, Karolina; Rakić, Tamara; Steffens, Melanie C</p> <p>2017-01-01</p> <p>Most research on ethnicity has focused on visual cues. However, accents are strong social cues that can match or contradict visual cues. We examined understudied reactions to people whose one cue suggests one ethnicity, whereas the other cue contradicts it. In an experiment conducted in Germany, job candidates spoke with an accent either congruent or incongruent with their (German or Turkish) appearance. Based on ethnolinguistic identity theory, we predicted that accents would be strong cues for categorization and evaluation. Based on expectancy violations theory we expected that incongruent targets would be evaluated more <span class="hlt">extremely</span> than congruent targets. Both predictions were confirmed: accents strongly influenced perceptions and Turkish-looking German-accented targets were perceived as most competent of all targets (and additionally most <span class="hlt">warm</span>). The findings show that bringing together visual and auditory information yields a more complete picture of the processes underlying impression formation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..14.3397B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..14.3397B"><span id="translatedtitle">Global <span class="hlt">Warming</span> And Meltwater</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bratu, S.</p> <p>2012-04-01</p> <p> glaciers, permafrost and sea ice. Other likely effects of the <span class="hlt">warming</span> include more frequent occurrences of <span class="hlt">extreme</span> weather events including heat waves, droughts and heavy rainfall events, species extinctions due to shifting temperature regimes, and changes in agricultural yields. Meltwater is the water released by the melting of snow or ice, including glacial ice and ice shelves in the oceans. Meltwater is often found in the ablation zone of glaciers, where the rate of snow cover is reduced. In a report published in June 2007, the United Nations Environment Program estimated that global <span class="hlt">warming</span> could lead to 40% of the world's population being affected by the loss of glaciers, snow and the associated meltwater in Asia. This is one of many activities of the physics laboratory that the students of our high school are involved in.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ACP....16.4757S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ACP....16.4757S"><span id="translatedtitle">Precipitation and synoptic regime in two <span class="hlt">extreme</span> years 2009 and 2010 at Dome C, Antarctica - implications for ice core interpretation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schlosser, Elisabeth; Stenni, Barbara; Valt, Mauro; Cagnati, Anselmo; Powers, Jordan G.; Manning, Kevin W.; Raphael, Marilyn; Duda, Michael G.</p> <p>2016-04-01</p> <p>At the East Antarctic deep ice core drilling site Dome C, daily precipitation measurements were initiated in 2006 and are being continued until today. The amounts and stable isotope ratios of the precipitation samples as well as crystal types are determined. Within the measuring period, the two years 2009 and 2010 showed striking contrasting temperature and precipitation anomalies, particularly in the <span class="hlt">winter</span> seasons. The reasons for these anomalies are analysed using data from the mesoscale atmospheric model WRF (Weather Research and Forecasting Model) run under the Antarctic Mesoscale Prediction System (AMPS). 2009 was relatively <span class="hlt">warm</span> and moist due to frequent <span class="hlt">warm</span> air intrusions connected to amplification of Rossby waves in the circumpolar westerlies, whereas the <span class="hlt">winter</span> of 2010 was <span class="hlt">extremely</span> dry and cold. It is shown that while in 2010 a strong zonal atmospheric flow was dominant, in 2009 an enhanced meridional flow prevailed, which increased the meridional transport of heat and moisture onto the East Antarctic plateau and led to a number of high-precipitation/<span class="hlt">warming</span> events at Dome C. This was also evident in a positive (negative) SAM (Southern Annular Mode) index and a negative (positive) ZW3 (zonal wave number three) index during the <span class="hlt">winter</span> months of 2010 (2009). Changes in the frequency or seasonality of such event-type precipitation can lead to a strong bias in the air temperature derived from stable water isotopes in ice cores.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ACPD...1530473S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ACPD...1530473S"><span id="translatedtitle">Precipitation regime and stable oxygen isotopes at Dome C, East Antarctica - a comparison of two <span class="hlt">extreme</span> years 2009 and 2010</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schlosser, E.; Stenni, B.; Valt, M.; Cagnati, A.; Powers, J. G.; Manning, K. W.; Raphael, M.; Duda, M. G.</p> <p>2015-11-01</p> <p>At the East Antarctic deep ice core drilling site Dome C, daily precipitation measurements have been initiated in 2006 and are being continued until today. The amounts and stable isotope ratios of the precipitation samples as well as crystal types are determined. Within the measuring period, the two years 2009 and 2010 showed striking contrasting temperature and precipitation anomalies, particularly in the <span class="hlt">winter</span> seasons. The reasons for these anomalies and their relation to stable isotope ratios are analysed using data from the mesoscale atmospheric model WRF (Weather Research and Forecasting Model) run under the Antarctic Mesoscale Prediction System (AMPS). 2009 was relatively <span class="hlt">warm</span> and moist due to frequent <span class="hlt">warm</span> air intrusions connected to amplification of Rossby waves in the circumpolar westerlies, whereas the <span class="hlt">winter</span> of 2010 was <span class="hlt">extremely</span> dry and cold. It is shown that while in 2010 a strong zonal atmospheric flow was dominant, in 2009 an enhanced meridional flow prevailed, which increased the meridional transport of heat and moisture onto the East Antarctic plateau and led to a number of high-precipitation/<span class="hlt">warming</span> events at Dome C. This was also evident in a positive (negative) SAM index and a negative (positive) ZW3 index during the <span class="hlt">winter</span> months of 2010 (2009). Changes in the frequency or seasonality of such event-type precipitation can lead to a strong bias in the air temperature derived from stable water isotopes in ice cores.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012MAP...115..173Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012MAP...115..173Y"><span id="translatedtitle"><span class="hlt">Extreme</span> drought event of 2009/2010 over southwestern China</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yang, Jing; Gong, Daoyi; Wang, Wenshan; Hu, Miao; Mao, Rui</p> <p>2012-02-01</p> <p>The <span class="hlt">extreme</span> drought of 2009/2010 over southwestern China is the driest event with the lowest percentage rainfall anomaly and the longest non-rain days during <span class="hlt">winter</span> season (October-February) in the past 50 years, and also the severest one with the lowest percentage rainfall anomaly at the same period since 1880. The drought domain is characterized with anomalous <span class="hlt">warming</span> and drying in the mid-lower troposphere as well as an evident anomalous subsidence. The favorable circulation anomalies for this drought are associated with the following two factors. One is the strongest negative-phase Arctic Oscillation during 2009/2010 <span class="hlt">winter</span> that accompanies with a weakened Middle East Jet Stream (MEJS), the cyclonic anomaly over Arabian Sea (AS), the anticyclonic anomaly over Tibet and the cyclonic anomaly over Lake Baikal. The weakened MEJS, the AS cyclonic anomaly and the Tibet anticyclonic anomaly weaken the Southern Branch Trough (SBT) that directly decreases the moisture transport toward the southwestern China; the cyclonic anomaly over the Lake Baikal causes a deepened and westward shifted East Asian Major Trough (EAT) so that dry cold air behind the EAT easily invades down to southwestern China. The AS cyclonic anomaly favors the westward extension of Western Pacific Subtropical High (WPSH). The westward extension of WPSH is also associated with the second factor that is the El Nino Modoki event during 2009/2010 autumn-<span class="hlt">winter</span>. The intensification and westward extension of WPSH enhance the local subsidence, weaken the SBT and exacerbate this drought.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ClDy..tmp...91C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ClDy..tmp...91C"><span id="translatedtitle">Impacts of <span class="hlt">winter</span> NPO on subsequent <span class="hlt">winter</span> ENSO: sensitivity to the definition of NPO index</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Shangfeng; Wu, Renguang</p> <p>2017-03-01</p> <p>This study investigates the linkage between boreal <span class="hlt">winter</span> North Pacific Oscillation (NPO) and subsequent <span class="hlt">winter</span> El Niño-Southern Oscillation (ENSO) based on seven different NPO indices. Results show that the influence of <span class="hlt">winter</span> NPO on the subsequent <span class="hlt">winter</span> El Niño is sensitive to how the NPO is defined. A significant NPO-El Niño connection is obtained when the NPO-related anomalous cyclone over the subtropical North Pacific extends to near-equatorial regions. The anomalous cyclone induces <span class="hlt">warm</span> sea surface temperature (SST) anomalies through modulating surface heat fluxes. These <span class="hlt">warm</span> SST anomalies are able to maintain into the following spring and summer through an air-sea coupled process and in turn induce significant westerly wind anomalies over the tropical western Pacific. In contrast, the NPO-El Niño relationship is unclear when the NPO-related anomalous cyclone over the subtropical North Pacific is confined to off-equatorial regions and cannot induce significant <span class="hlt">warm</span> SST anomalies over the subtropical North Pacific. The present study suggests that definitions of NPO should be taken into account when using NPO to predict ENSO. In particular, we recommend defining the NPO index based on the empirical orthogonal function technique over appropriate region that does not extend too far north.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013CliPD...9.6459S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013CliPD...9.6459S"><span id="translatedtitle"><span class="hlt">Extreme</span> <span class="hlt">warming</span>, photic zone euxinia and sea level rise during the Paleocene/Eocene Thermal Maximum on the Gulf of Mexico Coastal Plain; connecting marginal marine biotic signals, nutrient cycling and ocean deoxygenation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sluijs, A.; van Roij, L.; Harrington, G. J.; Schouten, S.; Sessa, J. A.; LeVay, L. J.; Reichart, G.-J.; Slomp, C. P.</p> <p>2013-12-01</p> <p>The Paleocene/Eocene Thermal Maximum (PETM, ~56 Ma) was a ~200 kyr episode of global <span class="hlt">warming</span>, associated with massive injections of 13C-depleted carbon into the ocean-atmosphere system. Although climate change during the PETM is relatively well constrained, effects on marine oxygen and nutrient cycling remain largely unclear. We identify the PETM in a sediment core from the US margin of the Gulf of Mexico. Biomarker-based paleotemperature proxies (MBT/CBT and TEX86) indicate that continental air and sea surface temperatures <span class="hlt">warmed</span> from 27-29 °C to ~35 °C, although variations in the relative abundances of terrestrial and marine biomarkers may have influenced the record. Vegetation changes as recorded from pollen assemblages supports profound <span class="hlt">warming</span>. Lithology, relative abundances of terrestrial vs. marine palynomorphs as well as dinoflagellate cyst and biomarker assemblages indicate sea level rise during the PETM, consistent with previously recognized eustatic rise. The recognition of a maximum flooding surface during the PETM changes regional sequence stratigraphic interpretations, which allows us to exclude the previously posed hypothesis that a nearby fossil found in PETM-deposits represents the first North American primate. Within the PETM we record the biomarker isorenieratane, diagnostic of euxinic photic zone conditions. A global data compilation indicates that deoxygenation occurred in large regions of the global ocean in response to <span class="hlt">warming</span>, hydrological change, and carbon cycle feedbacks, particularly along continental margins, analogous to modern trends. Seafloor deoxygenation and widespread anoxia likely caused phosphorus regeneration from suboxic and anoxic sediments. We argue that this fuelled shelf eutrophication, as widely recorded from microfossil studies, increasing organic carbon burial along continental margins as a negative feedback to carbon input and global <span class="hlt">warming</span>. If properly quantified with future work, the PETM offers the opportunity to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014NatSR...4E6890E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014NatSR...4E6890E"><span id="translatedtitle"><span class="hlt">Warming</span> shifts `worming': effects of experimental <span class="hlt">warming</span> on invasive earthworms in northern 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>Eisenhauer, Nico; Stefanski, Artur; Fisichelli, Nicholas A.; Rice, Karen; Rich, Roy; Reich, Peter B.</p> <p>2014-11-01</p> <p>Climate change causes species range shifts and potentially alters biological invasions. The invasion of European earthworm species across northern North America has severe impacts on native ecosystems. Given the long and cold <span class="hlt">winters</span> in that region that to date supposedly have slowed earthworm invasion, future <span class="hlt">warming</span> is hypothesized to accelerate earthworm invasions into yet non-invaded regions. Alternatively, <span class="hlt">warming</span>-induced reductions in soil water content (SWC) can also decrease earthworm performance. We tested these hypotheses in a field <span class="hlt">warming</span> experiment at two sites in Minnesota, USA by sampling earthworms in closed and open canopy in three temperature treatments in 2010 and 2012. Structural equation modeling revealed that detrimental <span class="hlt">warming</span> effects on earthworm densities and biomass could indeed be partly explained by <span class="hlt">warming</span>-induced reductions in SWC. The direction of <span class="hlt">warming</span> effects depended on the current average SWC: <span class="hlt">warming</span> had neutral to positive effects at high SWC, whereas the opposite was true at low SWC. Our results suggest that <span class="hlt">warming</span> limits the invasion of earthworms in northern North America by causing less favorable soil abiotic conditions, unless <span class="hlt">warming</span> is accompanied by increased and temporally even distributions of rainfall sufficient to offset greater water losses from higher evapotranspiration.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25363633','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25363633"><span id="translatedtitle"><span class="hlt">Warming</span> shifts 'worming': effects of experimental <span class="hlt">warming</span> on invasive earthworms in northern North America.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Eisenhauer, Nico; Stefanski, Artur; Fisichelli, Nicholas A; Rice, Karen; Rich, Roy; Reich, Peter B</p> <p>2014-11-03</p> <p>Climate change causes species range shifts and potentially alters biological invasions. The invasion of European earthworm species across northern North America has severe impacts on native ecosystems. Given the long and cold <span class="hlt">winters</span> in that region that to date supposedly have slowed earthworm invasion, future <span class="hlt">warming</span> is hypothesized to accelerate earthworm invasions into yet non-invaded regions. Alternatively, <span class="hlt">warming</span>-induced reductions in soil water content (SWC) can also decrease earthworm performance. We tested these hypotheses in a field <span class="hlt">warming</span> experiment at two sites in Minnesota, USA by sampling earthworms in closed and open canopy in three temperature treatments in 2010 and 2012. Structural equation modeling revealed that detrimental <span class="hlt">warming</span> effects on earthworm densities and biomass could indeed be partly explained by <span class="hlt">warming</span>-induced reductions in SWC. The direction of <span class="hlt">warming</span> effects depended on the current average SWC: <span class="hlt">warming</span> had neutral to positive effects at high SWC, whereas the opposite was true at low SWC. Our results suggest that <span class="hlt">warming</span> limits the invasion of earthworms in northern North America by causing less favorable soil abiotic conditions, unless <span class="hlt">warming</span> is accompanied by increased and temporally even distributions of rainfall sufficient to offset greater water losses from higher evapotranspiration.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011ERL.....6c1002H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011ERL.....6c1002H"><span id="translatedtitle">Global <span class="hlt">warming</span>: it's not only size that matters</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hegerl, Gabriele C.</p> <p>2011-09-01</p> <p> impacts than temperatures that have occurred frequently due to internal climate variability. Determining when exactly temperatures enter unusual ranges may be done in many different ways (and the paper shows several, and more could be imagined), but the main result of first local emergence in low latitudes remains robust. A worrying factor is that the regions where the signal is expected to emerge first, or is already emerging are largely regions in Africa, parts of South and Central America, and the Maritime Continent; regions that are vulnerable to climate change for a variety of regions (see IPCC 2007), and regions which contribute generally little to global greenhouse gas emissions. In contrast, strong emissions of greenhouse gases occur in regions of low <span class="hlt">warming</span>-to-variability ratio. To get even closer to the relevance of this finding for impacts, it would be interesting to place the emergence of highly unusual summer temperatures in the context not of internal variability, but in the context of variability experienced by the climate system prior to the 20th century, as, e.g. documented in palaeoclimatic reconstructions and simulated in simulations of the last millennium (see Jansen et al 2007). External forcing has moved the temperature range around more strongly for some regions and in some seasons than others. For example, while reconstructions of summer temperatures in Europe appear to show small long-term variations, <span class="hlt">winter</span> shows deep drops in temperature in the little Ice Age and a long-term increase since then (Luterbacher et al 2004), which was at least partly caused by external forcing (Hegerl et al 2011a) and therefore 'natural variability' may be different from internal variability. A further interesting question in attempts to provide a climate-based proxy for impacts of climate change is: to what extent does the rapidity of change matter, and how does it compare to trends due to natural variability? It is reasonable to assume that fast changes impact</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20060033954&hterms=Chlorine&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DChlorine','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20060033954&hterms=Chlorine&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DChlorine"><span id="translatedtitle">Measurements of Chlorine Partitioning in the <span class="hlt">Winter</span> Arctic Stratosphere</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stachnik, R.; Salawitch, R.; Engel, A.; Schmidt, U.</p> <p>1999-01-01</p> <p>Under the <span class="hlt">extremely</span> cold conditions in the polar <span class="hlt">winter</span> stratosphere, heterogeneous reactions involving HCl and CIONO(sub 2) on the surfaces of polar stratospheric cloud particles can release large amounts of reactive chlorine from these reservoirs leading to rapid chemical loss of ozone in the Arctic lower stratosphere during late <span class="hlt">winter</span> and early spring.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/1000579','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/1000579"><span id="translatedtitle">Distribution of alewives in southeastern Lake Ontario in autumn and <span class="hlt">winter</span>: a clue to <span class="hlt">winter</span> mortalities</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Bergstedt, Roger A.; O'Gorman, Robert</p> <p>1989-01-01</p> <p>Alewives Alosa pseudoharengus in the Great Lakes are thought to avoid <span class="hlt">extreme</span> cold in <span class="hlt">winter</span> by moving to deep water where the temperature is usually highest because of inverse thermal stratification. Information collected in Lake Ontario during autumn and <span class="hlt">winter</span> 1981–1984 with an echo sounder and bottom and midwater trawls indicated that many alewives remained at depths above 110 m, regardless of water temperature. Alewives in the Great Lakes that did not descend to greater depths would be exposed to potentially lethal temperatures during cold <span class="hlt">winters</span>.inters.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27910905','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27910905"><span id="translatedtitle">Magnitude and pattern of Arctic <span class="hlt">warming</span> governed by the seasonality of radiative forcing.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bintanja, R; Krikken, F</p> <p>2016-12-02</p> <p>Observed and projected climate <span class="hlt">warming</span> is strongest in the Arctic regions, peaking in autumn/<span class="hlt">winter</span>. Attempts to explain this feature have focused primarily on identifying the associated climate feedbacks, particularly the ice-albedo and lapse-rate feedbacks. Here we use a state-of-the-art global climate model in idealized seasonal forcing simulations to show that Arctic <span class="hlt">warming</span> (especially in <span class="hlt">winter</span>) and sea ice decline are particularly sensitive to radiative forcing in spring, during which the energy is effectively 'absorbed' by the ocean (through sea ice melt and ocean <span class="hlt">warming</span>, amplified by the ice-albedo feedback) and consequently released to the lower atmosphere in autumn and <span class="hlt">winter</span>, mainly along the sea ice periphery. In contrast, <span class="hlt">winter</span> radiative forcing causes a more uniform response centered over the Arctic Ocean. This finding suggests that intermodel differences in simulated Arctic (<span class="hlt">winter</span>) <span class="hlt">warming</span> can to a considerable degree be attributed to model uncertainties in Arctic radiative fluxes, which peak in summer.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFM.B24B..02Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFM.B24B..02Y"><span id="translatedtitle">Recent <span class="hlt">Extremes</span> in European Climate: Assessment, Case Studies and Impacts</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yiou, P.; Vautard, R.; D'Andrea, F.; Cattiaux, J.; Naveau, P.; Ciais, P.; Garnier, E.</p> <p>2008-12-01</p> <p>During the last centuries and up to the present decade, <span class="hlt">extreme</span> climate events have certainly had larger economic impacts than any trend of temperature in Europe. In addition to an intrinsic scientific interest, their study is thus essential for society. One of the challenges of their investigation is that, depending on their definition, <span class="hlt">extreme</span> climate events potentially have a behavior that is not connected to the secular temperature trend in a simple fashion. This presentation will review the statistical assessments of <span class="hlt">extremes</span> in Europe, focusing on surface temperature, precipitation, and their connections with large-scale features of the atmospheric circulation. In particular, the questions of modeling their severity and frequency will be discussed in the first part of the presentation. I will then give two kinds of examples of European climate <span class="hlt">extremes</span>: summer heatwaves and droughts, and <span class="hlt">winter</span> <span class="hlt">warm</span> waves. The mechanisms leading to such phenomena will be explored, and I will examine some of the impacts on the biosphere that were recently observed. In order to provide a long term perspective of those events, examples of historical droughts in France will be presented and connected with proxy records of temperature. It appears that the mechanisms that are favored for present-day climate might still have been valid during the past centuries. To conclude, new challenges for dynamical and statistical modeling will be explored.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19870018783','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19870018783"><span id="translatedtitle">Dynamic characteristics of observed sudden <span class="hlt">warmings</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Dartt, D. G.; Venne, D. E.</p> <p>1986-01-01</p> <p>The planetary wave dynamics of stratospheric sudden <span class="hlt">warmings</span> in the Northern Hemisphere for a large number of observed events that occurred during <span class="hlt">winters</span> from 1970 to 1975 and 1978 to 1981 are investigated. The analysis describes wave propagation and zonal flow interaction from the troposphere upwards to near 50 km, and in some years to near 80 km. Three primary topics are covered here: (1) the interaction of zonally propagating and quasi-stationary planetary waves during <span class="hlt">warming</span> events; (2) planetary wave influence on zonal flow near the stratopause; and (3) planetary wave propagation to near 80 km as seen from Stratospheric and Mesospheric Sounder (SAMS) data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/471027','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/471027"><span id="translatedtitle">Global <span class="hlt">warming</span>, insurance losses and financial industry</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Low, N.C.</p> <p>1996-12-31</p> <p>Global <span class="hlt">warming</span> causes <span class="hlt">extremely</span> bad weather in the near term. They have already caught the attention of the insurance industry, as they suffered massive losses in the last decade. Twenty-one out of the 25 largest catastrophes in the US, mainly in the form of hurricanes have occurred in the last decade. The insurance industry has reacted by taking the risk of global <span class="hlt">warming</span> in decisions as to pricing and underwriting decisions. But they have yet to take a more active role in regulating the factors that contributes to global <span class="hlt">warming</span>. How global <span class="hlt">warming</span> can impact the financial industry and the modern economy is explored. Insurance and modern financial derivatives are key to the efficient functioning of the modern economy, without which the global economy can still function but will take a giant step backward. Any risk as global <span class="hlt">warming</span> that causes economic surprises will hamper the efficient working of the financial market and the modern economy.</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('http://adsabs.harvard.edu/abs/2011AGUFMGC21A0857W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMGC21A0857W"><span id="translatedtitle">Modeling the Pineapple Express phenomenon via Multivariate <span class="hlt">Extreme</span> Value Theory</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Weller, G.; Cooley, D. S.</p> <p>2011-12-01</p> <p>The pineapple express (PE) phenomenon is responsible for producing <span class="hlt">extreme</span> <span class="hlt">winter</span> precipitation events in the coastal and mountainous regions of the western United States. Because the PE phenomenon is also associated with <span class="hlt">warm</span> temperatures, the heavy precipitation and associated snowmelt can cause destructive flooding. In order to study impacts, it is important that regional climate models from NARCCAP are able to reproduce <span class="hlt">extreme</span> precipitation events produced by PE. We define a daily precipitation quantity which captures the spatial extent and intensity of precipitation events produced by the PE phenomenon. We then use statistical <span class="hlt">extreme</span> value theory to model the tail dependence of this quantity as seen in an observational data set and each of the six NARCCAP regional models driven by NCEP reanalysis. We find that most NCEP-driven NARCCAP models do exhibit tail dependence between daily model output and observations. Furthermore, we find that not all <span class="hlt">extreme</span> precipitation events are pineapple express events, as identified by Dettinger et al. (2011). The synoptic-scale atmospheric processes that drive <span class="hlt">extreme</span> precipitation events produced by PE have only recently begun to be examined. Much of the current work has focused on pattern recognition, rather than quantitative analysis. We use daily mean sea-level pressure (MSLP) fields from NCEP to develop a "pineapple express index" for <span class="hlt">extreme</span> precipitation, which exhibits tail dependence with our observed precipitation quantity for pineapple express events. We build a statistical model that connects daily precipitation output from the WRFG model, daily MSLP fields from NCEP, and daily observed precipitation in the western US. Finally, we use this model to simulate future observed precipitation based on WRFG output driven by the CCSM model, and our pineapple express index derived from future CCSM output. Our aim is to use this model to develop a better understanding of the frequency and intensity of <span class="hlt">extreme</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19860018268&hterms=Gelman&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D30%26Ntt%3DGelman','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19860018268&hterms=Gelman&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D30%26Ntt%3DGelman"><span id="translatedtitle">Discrimination of a major stratospheric <span class="hlt">warming</span> event in February-March 1984 from earlier minor <span class="hlt">warmings</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Johnson, K. W.; Quiroz, R. S.; Gelman, M. E.</p> <p>1985-01-01</p> <p>As part of its responsibility for stratospheric monitoring, the Climate Analysis Center derives time trends of various dynamic parameters from NMC stratospheric analyses. Selected figures from this stratospheric monitoring data base are published in Climate Diagnostics Bulletin in March and October, after each hemispheric <span class="hlt">winter</span>. During the Northern Hemisphere <span class="hlt">winter</span> of December 1983-February 1984 several <span class="hlt">warming</span> events may be seen in the plot of 60 deg. N zonal mean temperatures for 10 mb. Minor <span class="hlt">warmings</span> may be noted in early December, late December, mid January and early February. A major <span class="hlt">warming</span> with the 60 deg. N zonal mean temperatures reaching -40C is observed in late February, associated with a circulation reversal. In all of the minor <span class="hlt">warming</span> episodes, there is a polarward movement of the Aleutian anticyclone; however, at 10 mb the North Pole remains in the cyclonic circulation of the stratospheric vortex which is not displaced far from its usual position. In the case of the later February major <span class="hlt">warming</span>, the 10 mb circulation pattern over the North Pole is anticyclonic, and the cyclonic circulation has moved to the south and east with a considerable elongation. Cross sections of heat transport and momentum transport are not dramatically different for the minor and major <span class="hlt">warming</span> episodes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMPA21B1873R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMPA21B1873R"><span id="translatedtitle">Communicating Certainty About Nuclear <span class="hlt">Winter</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Robock, A.</p> <p>2013-12-01</p> <p> Report of the Intergovernmental Panel on Climate Change (IPCC), I inserted a paragraph pointing out that volcanic eruptions serve as an analog that supports new work on nuclear <span class="hlt">winter</span>. This is the first time that nuclear <span class="hlt">winter</span> has been in the IPCC report. I will tell the story of the discussions within our chapter, with review editors, and with the IPCC leadership that resulted in a box in Chapter 8 that discusses nuclear <span class="hlt">winter</span>. We gave a briefing to John Holdren, the President's Science Advisor, about the work. Daniel Ellsberg, Fidel Castro, and Mikhail Gorbachev found out about our work, and used the results to appeal for nuclear abolition. In 2013 the work was featured at the Conference on the Humanitarian Impact of Nuclear Weapons in Oslo, Norway attended by 132 nations, and I gave a TEDx talk, I published an opinion piece on the CNN website, and I gave an invited public lecture in Nagasaki, Japan, all about the climatic consequences of nuclear war. I am now using Twitter and Facebook to communicate about nuclear <span class="hlt">winter</span>. The threat that nuclear weapons pose to the planet is a much easier problem to solve than global <span class="hlt">warming</span>. We need to eliminate nuclear weapons so we have the luxury of working on the global <span class="hlt">warming</span> problem without the possibility of the existential global threat still posed by the global nuclear arsenal.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24659171','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24659171"><span id="translatedtitle"><span class="hlt">Extreme</span> weather event in spring 2013 delayed breeding time of Great Tit and Blue Tit.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Glądalski, Michał; Bańbura, Mirosława; Kaliński, Adam; Markowski, Marcin; Skwarska, Joanna; Wawrzyniak, Jarosław; Zieliński, Piotr; Bańbura, Jerzy</p> <p>2014-12-01</p> <p>The impact of climatic changes on life cycles by re-scheduling the timing of reproduction is an important topic in studies of biodiversity. Global <span class="hlt">warming</span> causes and will probably cause in the future not only raising temperatures but also an increasing frequency of <span class="hlt">extreme</span> weather events. In 2013, the <span class="hlt">winter</span> in central and north Europe ended late, with low temperatures and long-retained snow cover--this <span class="hlt">extreme</span> weather phenomenon acted in opposition to the increasing temperature trend. In 2013, thermal conditions measured by the warmth sum in the period 15 March–15 April, a critical time for early breeding passerines, went far beyond the range of the warmth sums for at least 40 preceding years. Regardless of what was the reason for the <span class="hlt">extreme</span> early spring 2013 and assuming that there is a potential for more atypical years because of climate change, we should look closely at every <span class="hlt">extreme</span> phenomenon and its consequences for the phenology of organisms. In this paper, we report that the prolonged occurrence of <span class="hlt">winter</span> conditions during the time that is crucial for Blue Tit (Cyanistes caeruleus) and Great Tit (Parus major) reproduction caused a substantial delay in the onset of egg laying in comparison with typical springs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.8384G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.8384G"><span id="translatedtitle">Storing snow for the next <span class="hlt">winter</span>: Two case studies on the application of snow farming.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Grünewald, Thomas; Wolfsperger, Fabian</p> <p>2016-04-01</p> <p>Snow farming is the conservation of snow during the <span class="hlt">warm</span> half-year. This means that large piles of snow are formed in spring in order to be conserved over the summer season. Well-insulating materials such as chipped wood are added as surface cover to reduce melting. The aim of snow farming is to provide a "snow guaranty" for autumn or early <span class="hlt">winter</span> - this means that a specific amount of snow will definitively be available, independent of the weather conditions. The conserved snow can then be used as basis for the preparation of <span class="hlt">winter</span> sports grounds such as cross-country tracks or ski runs. This helps in the organization of early <span class="hlt">winter</span> season sport events such as World Cup races or to provide appropriate training conditions for athletes. We present a study on two snow farming projects, one in Davos (Switzerland) and one in the Martell valley of South Tyrol. At both places snow farming has been used for several years. For the summer season 2015, we monitored both snow piles in order to assess the amount of snow conserved. High resolution terrestrial laser scanning was performed to measure snow volumes of the piles at the beginning and at the end of the summer period. Results showed that only 20% to 30 % of the snow mass was lost due to ablation. This mass loss was surprisingly low considering the <span class="hlt">extremely</span> <span class="hlt">warm</span> and dry summer. In order to identify the most relevant drivers of snow melt we also present simulations with the sophisticated snow cover models SNOWPACK and Alpine3D. The simulations are driven by meteorological input data recorded in the vicinity of the piles and enable a detailed analysis of the relevant processes controlling the energy balance. The models can be applied to optimize settings for snow farming and to examine the suitability of new locations, configurations or cover material for future snow farming projects.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1236702','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1236702"><span id="translatedtitle">Historical trends and <span class="hlt">extremes</span> in boreal Alaska river basins</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Bennett, Katrina E.; Cannon, Alex J.; Hinzman, Larry</p> <p>2015-05-12</p> <p>Climate change will shift the frequency, intensity, duration and persistence of <span class="hlt">extreme</span> hydroclimate events and have particularly disastrous consequences in vulnerable systems such as the <span class="hlt">warm</span> permafrost-dominated Interior region of boreal Alaska. This work focuses on recent research results from nonparametric trends and nonstationary generalized <span class="hlt">extreme</span> value (GEV) analyses at eight Interior Alaskan river basins for the past 50/60 years (1954/64–2013). Trends analysis of maximum and minimum streamflow indicates a strong (>+50%) and statistically significant increase in 11-day flow events during the late fall/<span class="hlt">winter</span> and during the snowmelt period (late April/mid-May), followed by a significant decrease in the 11-day flow events during the post-snowmelt period (late May and into the summer). The April–May–June seasonal trends show significant decreases in maximum streamflow for snowmelt dominated systems (<–50%) and glacially influenced basins (–24% to –33%). Annual maximum streamflow trends indicate that most systems are experiencing declines, while minimum flow trends are largely increasing. Nonstationary GEV analysis identifies time-dependent changes in the distribution of spring <span class="hlt">extremes</span> for snowmelt dominated and glacially dominated systems. Temperature in spring influences the glacial and high elevation snowmelt systems and <span class="hlt">winter</span> precipitation drives changes in the snowmelt dominated basins. The Pacific Decadal Oscillation was associated with changes occurring in snowmelt dominated systems, and the Arctic Oscillation was linked to one lake dominated basin, with half of the basins exhibiting no change in response to climate variability. The paper indicates that broad scale studies examining trend and direction of change should employ multiple methods across various scales and consider regime dependent shifts to identify and understand changes in <span class="hlt">extreme</span> streamflow within boreal forested watersheds of Alaska.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1236702-historical-trends-extremes-boreal-alaska-river-basins','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1236702-historical-trends-extremes-boreal-alaska-river-basins"><span id="translatedtitle">Historical trends and <span class="hlt">extremes</span> in boreal Alaska river basins</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Bennett, Katrina E.; Cannon, Alex J.; Hinzman, Larry</p> <p>2015-05-12</p> <p>Climate change will shift the frequency, intensity, duration and persistence of <span class="hlt">extreme</span> hydroclimate events and have particularly disastrous consequences in vulnerable systems such as the <span class="hlt">warm</span> permafrost-dominated Interior region of boreal Alaska. This work focuses on recent research results from nonparametric trends and nonstationary generalized <span class="hlt">extreme</span> value (GEV) analyses at eight Interior Alaskan river basins for the past 50/60 years (1954/64–2013). Trends analysis of maximum and minimum streamflow indicates a strong (>+50%) and statistically significant increase in 11-day flow events during the late fall/<span class="hlt">winter</span> and during the snowmelt period (late April/mid-May), followed by a significant decrease in the 11-day flowmore » events during the post-snowmelt period (late May and into the summer). The April–May–June seasonal trends show significant decreases in maximum streamflow for snowmelt dominated systems (<–50%) and glacially influenced basins (–24% to –33%). Annual maximum streamflow trends indicate that most systems are experiencing declines, while minimum flow trends are largely increasing. Nonstationary GEV analysis identifies time-dependent changes in the distribution of spring <span class="hlt">extremes</span> for snowmelt dominated and glacially dominated systems. Temperature in spring influences the glacial and high elevation snowmelt systems and <span class="hlt">winter</span> precipitation drives changes in the snowmelt dominated basins. The Pacific Decadal Oscillation was associated with changes occurring in snowmelt dominated systems, and the Arctic Oscillation was linked to one lake dominated basin, with half of the basins exhibiting no change in response to climate variability. The paper indicates that broad scale studies examining trend and direction of change should employ multiple methods across various scales and consider regime dependent shifts to identify and understand changes in <span class="hlt">extreme</span> streamflow within boreal forested watersheds of Alaska.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/467747','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/467747"><span id="translatedtitle">Cold climate bioventing with soil <span class="hlt">warming</span> in Alaska</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sayles, G.D.; Brenner, R.C.; Leeson, A.; Hinchee, R.E.; Vogel, C.M.; Miller, R.N.</p> <p>1995-12-31</p> <p>In the heart of Alaska, a 3-year field study was conducted of bioventing in conjunction with several soil <span class="hlt">warming</span> methods. The contamination was JP-4 jet fuel. The soil <span class="hlt">warming</span> methods evaluated, chosen for their apparent low cost, were (1) application of <span class="hlt">warm</span> water at a low rate, (2) enhanced solar <span class="hlt">warming</span> by covering the surface with clear plastic in the summer and covering the surface with insulation in the <span class="hlt">winter</span>, and (3) buried heat pipe. The <span class="hlt">warm</span> water and buried heat tape methods performed best, maintaining summer-like 10 to 20 C temperatures in the test plots year round, compared to the temperature of the unheated control plot, which dipped to {minus}1 C in the <span class="hlt">winter</span>. The solar/insulation <span class="hlt">warming</span> method showed a modest improvement in temperature over the unheated control test plot. The annual average temperatures of the <span class="hlt">warm</span> water, heat tape, solar, and control plots were 16.9, 14.5, 6.1, and 3.5 C, respectively. The biodegradation rates, measured by in situ respirometry, were higher in plots with higher temperatures and followed the Arrhenius relationship. Despite the low temperature, significant biodegradation was observed in the unheated plot during the <span class="hlt">winter</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009GPC....68..209G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009GPC....68..209G"><span id="translatedtitle">Climatic changes and associated impacts in the Mediterranean resulting from a 2 °C global <span class="hlt">warming</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Giannakopoulos, C.; Le Sager, P.; Bindi, M.; Moriondo, M.; Kostopoulou, E.; Goodess, C. M.</p> <p>2009-08-01</p> <p>Climatic changes over the Mediterranean basin in 2031-2060, when a 2 °C global <span class="hlt">warming</span> is most likely to occur, are investigated with the HadCM3 global circulation model and their impacts on human activities and natural ecosystem are assessed. Precipitation and surface temperature changes are examined through mean and <span class="hlt">extreme</span> values analysis, under the A2 and B2 emission scenarios. Confidence in results is obtained via bootstrapping. Over the land areas, the <span class="hlt">warming</span> is larger than the global average. The rate of <span class="hlt">warming</span> is found to be around 2 °C in spring and <span class="hlt">winter</span>, while it reaches 4 °C in summer. An additional month of summer days is expected, along with 2-4 weeks of tropical nights. Increase in heatwave days and decrease in frost nights are expected to be a month inland. In the northern part of the basin the widespread drop in summer rainfall is partially compensated by a <span class="hlt">winter</span> precipitation increase. One to 3 weeks of additional dry days lead to a dry season lengthened by a week and shifted toward spring in the south of France and inland Algeria, and autumn elsewhere. In central Mediterranean droughts are extended by a month, starting a week earlier and ending 3 weeks later. The impacts of these climatic changes on human activities such as agriculture, energy, tourism and natural ecosystems (forest fires) are also assessed. Regarding agriculture, crops whose growing cycle occurs mostly in autumn and <span class="hlt">winter</span> show no changes or even an increase in yield. In contrast, summer crops show a remarkable decrease of yield. This different pattern is attributed to a lengthier drought period during summer and to an increased rainfall in <span class="hlt">winter</span> and autumn. Regarding forest fire risk, an additional month of risk is expected over a great part of the basin. Energy demand levels are expected to fall significantly during a warmer <span class="hlt">winter</span> period inland, whereas they seem to substantially increase nearly everywhere during summer. <span class="hlt">Extremely</span> high summer temperatures in the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.A32C..03V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.A32C..03V"><span id="translatedtitle">Simulation of <span class="hlt">Extreme</span> Arctic Cyclones in IPCC AR5 Experiments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vavrus, S. J.</p> <p>2012-12-01</p> <p>Although impending Arctic climate change is widely recognized, a wild card in its expression is how <span class="hlt">extreme</span> weather events in this region will respond to greenhouse <span class="hlt">warming</span>. Intense polar cyclones represent one type of high-latitude phenomena falling into this category, including very deep synoptic-scale cyclones and mesoscale polar lows. These systems inflict damage through high winds, heavy precipitation, and wave action along coastlines, and their impact is expected to expand in the future, when reduced sea ice cover allows enhanced wave energy. The loss of a buffering ice pack could greatly increase the rate of coastal erosion, which has already been increasing in the Arctic. These and related threats may amplify if <span class="hlt">extreme</span> Arctic cyclones become more frequent and/or intense in a <span class="hlt">warming</span> climate with much more open water to fuel them. This possibility has merit on the basis of GCM experiments, which project that greenhouse forcing causes lower mean sea level pressure (SLP) in the Arctic and a strengthening of the deepest storms over boreal high latitudes. In this study, the latest Coupled Model Intercomparison Project (CMIP5) climate model output is used to investigate the following questions: (1) What are the spatial and seasonal characteristics of <span class="hlt">extreme</span> Arctic cyclones? (2) How well do GCMs simulate these phenomena? (3) Are Arctic cyclones already showing the expected response to greenhouse <span class="hlt">warming</span> in climate models? To address these questions, a retrospective analysis is conducted of the transient 20th century simulations among the CMIP5 GCMs (spanning years 1850-2005). The results demonstrate that GCMs are able to reasonably represent <span class="hlt">extreme</span> Arctic cyclones and that the simulated characteristics do not depend significantly on model resolution. Consistent with observational evidence, climate models generate these storms primarily during <span class="hlt">winter</span> and within the climatological Aleutian and Icelandic Low regions. Occasionally the cyclones remain very intense</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4640126','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4640126"><span id="translatedtitle">Climate <span class="hlt">warming</span> could increase recruitment success in glacier foreland plants</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Mondoni, Andrea; Pedrini, Simone; Bernareggi, Giulietta; Rossi, Graziano; Abeli, Thomas; Probert, Robin J.; Ghitti, Michele; Bonomi, Costantino; Orsenigo, Simone</p> <p>2015-01-01</p> <p>Background and Aims Glacier foreland plants are highly threatened by global <span class="hlt">warming</span>. Regeneration from seeds on deglaciated terrain will be crucial for successful migration and survival of these species, and hence a better understanding of the impacts of climate change on seedling recruitment is urgently needed to predict future plant persistence in these environments. This study presents the first field evidence of the impact of climate change on recruitment success of glacier foreland plants. Methods Seeds of eight foreland species were sown on a foreland site at 2500 m a.s.l., and at a site 400 m lower in altitude to simulate a 2·7 °C increase in mean annual temperature. Soil from the site of origin was used to reproduce the natural germination substrate. Recruitment success, temperature and water potential were monitored for 2 years. The response of seed germination to <span class="hlt">warming</span> was further investigated in the laboratory. Key Results At the glacier foreland site, seedling emergence was low (0 to approx. 40 %) and occurred in summer in all species after seeds had experienced autumn and <span class="hlt">winter</span> seasons. However, at the warmer site there was a shift from summer to autumn emergence in two species and a significant increase of summer emergence (13–35 % higher) in all species except two. Survival and establishment was possible for 60–75 % of autumn-emerged seedlings and was generally greater under warmer conditions. Early snowmelt in spring caused the main ecological factors enhancing the recruitment success. Conclusions The results suggest that <span class="hlt">warming</span> will influence the recruitment of glacier foreland species primarily via the extension of the snow-free period in spring, which increases seedling establishment and results in a greater resistance to summer drought and <span class="hlt">winter</span> <span class="hlt">extremes</span>. The changes in recruitment success observed here imply that range shifts or changes in abundance are possible in a future warmer climate, but overall success may be dependent</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25585353','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25585353"><span id="translatedtitle">Effect of simulated fall heat waves on cold hardiness and <span class="hlt">winter</span> survival of hemlock looper, Lambdina fiscellaria (Lepidoptera: Geometridae).</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Vallières, Rosemarie; Rochefort, Sophie; Berthiaume, Richard; Hébert, Christian; Bauce, Éric</p> <p>2015-02-01</p> <p>The hemlock looper (Lambdina fiscellaria) is an important pest of eastern Canadian forests. The ongoing climate <span class="hlt">warming</span> could modify the seasonal ecology of this univoltine species that lays eggs at the end of summer and overwinters at this stage. Indeed, the increase in frequency and intensity of <span class="hlt">extreme</span> climatic events such as fall heat waves could interfere with the <span class="hlt">winter</span> metabolism of the hemlock looper. Moreover, the host plant quality, which influences the quantity of insect energetic reserves, the geographic origin of populations and the conditions prevailing during the cold acclimation period, could cause various responses of this pest to climate <span class="hlt">warming</span>. The main objective of this study is to determine the impact of these factors on hemlock looper <span class="hlt">winter</span> biology. In October 2010, hemlock looper eggs initially collected from two geographic areas in the province of Québec, and from parents reared on two host plants, were exposed to fall heat waves of different intensities during 5 consecutive days. Supercooling points and cryoprotectant levels were measured on eggs on four different dates in 2010-2011 and survival rate was measured in April 2011. Our results show that hemlock looper eggs have a very low supercooling point and high levels of trehalose, glucose and mannitol in September and November. However, there is no clear relationship between the concentration of these compounds and the decrease in supercooling points. Contents in trehalose, glucose and mannitol were significantly influenced by fall heat waves and by the origin of the population. <span class="hlt">Winter</span> survival of eggs from the temperate population was negatively affected by strong heat waves while the boreal population was not affected. This study suggests that the metabolism and <span class="hlt">winter</span> survival of temperate hemlock looper populations in Québec will be more affected by fall heat waves that will increase in frequency due to climate change, than boreal populations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/41805','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/41805"><span id="translatedtitle">Solar aquaculture: A <span class="hlt">wintering</span> technique for parent prawns</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Cao Jin Long</p> <p>1994-09-01</p> <p>A new method of providing the <span class="hlt">warm</span> water needed for parent prawn <span class="hlt">wintering</span> using solar energy is described. Using solar energy for prawn <span class="hlt">wintering</span> involves heat collection, heat storage and temperature maintenance. The system designed provides sufficient energy for the safe <span class="hlt">wintering</span> of prawns with suitable water temperatures. The temperature control facilities consist of three parts: a salt gradient solar pond, a shallow solar pond and a plastic house. The technique involves use of a shallow solar pond for collection and storage of heat. The average temperature in the <span class="hlt">wintering</span> pond plastic house was 11 degrees C and the minimum temperature in January was 5.4 degrees C. This system allowed the <span class="hlt">wintering</span> process to be conducted using solar energy alone and may extend aquaculture to higher latitudes. The ratio of net profit with the solar energy system over investment is 1.5 which makes it economically viable.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=timo&pg=4&id=EJ776062','ERIC'); return false;" href="http://eric.ed.gov/?q=timo&pg=4&id=EJ776062"><span id="translatedtitle"><span class="hlt">Winter</span> Art Education Project</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Jokela, Timo</p> <p>2007-01-01</p> <p>The purpose of this article is to describe how the Department of Art Education at the University of Lapland in Finland has developed <span class="hlt">winter</span> art as a method of environmental and community-based art education. I will focus on the Snow Show <span class="hlt">Winter</span> Art Education Project, a training project funded by the European Union and the State Provincial Office…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PCE....94...66F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PCE....94...66F"><span id="translatedtitle">Recent trends of <span class="hlt">extreme</span> temperature indices for the Iberian Peninsula</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fonseca, D.; Carvalho, M. J.; Marta-Almeida, M.; Melo-Gonçalves, P.; Rocha, A.</p> <p>2016-08-01</p> <p>Climate change and <span class="hlt">extreme</span> climate events have a significant impact on societies and ecosystems. As a result, climate change projections, especially related with <span class="hlt">extreme</span> temperature events, have gained increasing importance due to their impacts on the well-being of the population and ecosystems. However, most studies in the field are based on coarse global climate models (GCMs). In this study, we perform a high resolution downscaling simulation to evaluate recent trends of <span class="hlt">extreme</span> temperature indices. The model used was Weather Research and Forecast (WRF) forced by MPI-ESM-LR, which has been shown to be one of the more robust models to simulate European climate. The domain used in the simulations includes the Iberian Peninsula and the simulation covers the 1986-2005 period (i.e. recent past). In order to study <span class="hlt">extreme</span> temperature events, trends were computed using the Theil-Sen method for a set of temperature indexes defined by the Expert Team on Climate Change Detection and Indices (ETCCDI). For this, daily values of minimum and maximum temperatures were used. The trends of the indexes were computed for annual and seasonal values and the Mann-Kendall Trend test was used to evaluate their statistical significance. In order to validate the results, a second simulation, in which WRF was forced by ERA-Interim, was performed. The results suggest an increase in the number of <span class="hlt">warm</span> days and <span class="hlt">warm</span> nights, especially during summer and negative trends for cold nights and cold days for the summer and spring. For the <span class="hlt">winter</span>, contrary to the expected, the results suggest an increase in cold days and cold nights (<span class="hlt">warming</span> hiatus). This behavior is supported by the WRF simulation forced by ERA-Interim for the autumn days, pointing to an extension of the <span class="hlt">warming</span> hiatus phenomenon to the remaining seasons. These results should be used with caution since the period used to calculate the trends may not be long enough for this purpose. However, the general sign of trends are similar for</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003AtmRe..67..501M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003AtmRe..67..501M"><span id="translatedtitle"><span class="hlt">Winter</span> thunderstorms in central Europe in the past and the present</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Munzar, Jan; Franc, Marek</p> <p></p> <p>Thunderstorms in the territories of the Czech Republic and neighbouring countries are almost exclusively the only phenomena occurring in the <span class="hlt">warm</span> season. In the cold half of the year, from October to March, an average incidence of thunderstorms is only 2%, with the least occurrence being recorded in January. Yet, <span class="hlt">winter</span> thunderstorms are dangerous particularly for air traffic because during them, the cloud base is rapidly falling down and visibility is suddenly worsening due to heavy snowfall. Notwithstanding these facts, the issue of their occurrence in the central European space has been paid little attention so far. Long years of study into historical weather <span class="hlt">extremes</span> in the territory of the Czech Republic revealed over 10 chronicle entries on the occurrence of <span class="hlt">winter</span> thunderstorms in the period between November and February from the 16th to the beginning of the 20th centuries. The irregular phenomenon was even devoted three occasional prints in central Europe in the second half of the 16th century, two of which were issued in Germany. Fires caused by <span class="hlt">winter</span> thunderstorms were no sporadic cases. The occurrence of thunderstorms in <span class="hlt">winter</span> was apparently associated with the passage of pronounced cold fronts. This can be documented on cases from the end of December 1555 when heavy thunderstorms and consequent fires were recorded within a short period of time in Holland, Germany and in Czech lands. It is assumed that the situation in 1627 was similar when a <span class="hlt">winter</span> thunderstorm was recorded in Prague and in Holešov, southeastern Moravia on 28 December. In February 1581, a thunderstorm in Prague became one of three unusual events publicized by the local occasional newspaper. The beginning of modern studies into <span class="hlt">winter</span> thunderstorms dates back to the 1960s with the use of lightning flash counters and later also with the use of systems for large-scale lightning flash detection and localization. However, more comprehensive meteorological and climatological assessments of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ClDy...45.3257L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ClDy...45.3257L"><span id="translatedtitle">Evaluation of large-scale meteorological patterns associated with temperature <span class="hlt">extremes</span> in the NARCCAP regional climate model simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Loikith, Paul C.; Waliser, Duane E.; Lee, Huikyo; Neelin, J. David; Lintner, Benjamin R.; McGinnis, Seth; Mearns, Linda O.; Kim, Jinwon</p> <p>2015-12-01</p> <p>Large-scale meteorological patterns (LSMPs) associated with temperature <span class="hlt">extremes</span> are evaluated in a suite of regional climate model (RCM) simulations contributing to the North American Regional Climate Change Assessment Program. LSMPs are characterized through composites of surface air temperature, sea level pressure, and 500 hPa geopotential height anomalies concurrent with <span class="hlt">extreme</span> temperature days. Six of the seventeen RCM simulations are driven by boundary conditions from reanalysis while the other eleven are driven by one of four global climate models (GCMs). Four illustrative case studies are analyzed in detail. Model fidelity in LSMP spatial representation is high for cold <span class="hlt">winter</span> <span class="hlt">extremes</span> near Chicago. <span class="hlt">Winter</span> <span class="hlt">warm</span> <span class="hlt">extremes</span> are captured by most RCMs in northern California, with some notable exceptions. Model fidelity is lower for cool summer days near Houston and <span class="hlt">extreme</span> summer heat events in the Ohio Valley. Physical interpretation of these patterns and identification of well-simulated cases, such as for Chicago, boosts confidence in the ability of these models to simulate days in the tails of the temperature distribution. Results appear consistent with the expectation that the ability of an RCM to reproduce a realistically shaped frequency distribution for temperature, especially at the tails, is related to its fidelity in simulating LMSPs. Each ensemble member is ranked for its ability to reproduce LSMPs associated with observed <span class="hlt">warm</span> and cold <span class="hlt">extremes</span>, identifying systematically high performing RCMs and the GCMs that provide superior boundary forcing. The methodology developed here provides a framework for identifying regions where further process-based evaluation would improve the understanding of simulation error and help guide future model improvement and downscaling efforts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016TCry...10.2589W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016TCry...10.2589W"><span id="translatedtitle">Frequency and distribution of <span class="hlt">winter</span> melt events from passive microwave satellite data in the pan-Arctic, 1988-2013</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Libo; Toose, Peter; Brown, Ross; Derksen, Chris</p> <p>2016-11-01</p> <p>This study presents an algorithm for detecting <span class="hlt">winter</span> melt events in seasonal snow cover based on temporal variations in the brightness temperature difference between 19 and 37 GHz from satellite passive microwave measurements. An advantage of the passive microwave approach is that it is based on the physical presence of liquid water in the snowpack, which may not be the case with melt events inferred from surface air temperature data. The algorithm is validated using in situ observations from weather stations, snow pit measurements, and a surface-based passive microwave radiometer. The validation results indicate the algorithm has a high success rate for melt durations lasting multiple hours/days and where the melt event is preceded by <span class="hlt">warm</span> air temperatures. The algorithm does not reliably identify short-duration events or events that occur immediately after or before periods with <span class="hlt">extremely</span> cold air temperatures due to the thermal inertia of the snowpack and/or overpass and resolution limitations of the satellite data. The results of running the algorithm over the pan-Arctic region (north of 50° N) for the 1988-2013 period show that <span class="hlt">winter</span> melt events are relatively rare, totaling less than 1 week per <span class="hlt">winter</span> over most areas, with higher numbers of melt days (around two weeks per <span class="hlt">winter</span>) occurring in more temperate regions of the Arctic (e.g., central Québec and Labrador, southern Alaska and Scandinavia). The observed spatial pattern is similar to <span class="hlt">winter</span> melt events inferred with surface air temperatures from the ERA-Interim (ERA-I) and Modern Era-Retrospective Analysis for Research and Applications (MERRA) reanalysis datasets. There was little evidence of trends in <span class="hlt">winter</span> melt event frequency over 1988-2013 with the exception of negative trends over northern Europe attributed to a shortening of the duration of the <span class="hlt">winter</span> period. The frequency of <span class="hlt">winter</span> melt events is shown to be strongly correlated to the duration of <span class="hlt">winter</span> period. This must be taken into</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRD..12110394T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRD..12110394T"><span id="translatedtitle">Poleward transport variability in the Northern Hemisphere during final stratospheric <span class="hlt">warmings</span> simulated by CESM(WACCM)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Thiéblemont, Rémi; Matthes, Katja; Orsolini, Yvan J.; Hauchecorne, Alain; Huret, Nathalie</p> <p>2016-09-01</p> <p>Observational studies of Arctic stratospheric final <span class="hlt">warmings</span> have shown that tropical/subtropical air masses can be advected to high latitudes and remain confined within a long-lived "frozen-in" anticyclone (FrIAC) for several months. It was suggested that the frequency of FrIACs may have increased since 2000 and that their interannual variability may be modulated by (i) the occurrence of major stratospheric <span class="hlt">warmings</span> (mSSWs) in the preceding <span class="hlt">winter</span> and (ii) the phase of the quasi-biennial oscillation (QBO). In this study, we tested these observational-based hypotheses for the first time using a chemistry climate model. Three 145 year sensitivity experiments were performed with the National Center of Atmospheric Research's Community Earth System Model (CESM): one control experiment including only natural variability, one with an <span class="hlt">extreme</span> greenhouse gas emission scenario, and one without the QBO in the tropical stratosphere. In comparison with reanalysis, the model simulates a realistic frequency and characteristics of FrIACs, which occur under an abrupt and early <span class="hlt">winter</span>-to-summer stratospheric circulation transition, driven by enhanced planetary wave activity. Furthermore, the model results support the suggestion that the development of FrIACs is favored by an easterly QBO in the middle stratosphere and by the absence of mSSWs during the preceding <span class="hlt">winter</span>. The lower stratospheric persistence of background dynamical state anomalies induced by deep mSSWs leads to less favorable conditions for planetary waves to enter the high-latitude stratosphere in April, which in turn decreases the probability of FrIAC development. Our model results do not suggest that climate change conditions (RCP8.5 scenario) influence FrIAC occurrences.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=warmup&pg=7&id=EJ404495','ERIC'); return false;" href="http://eric.ed.gov/?q=warmup&pg=7&id=EJ404495"><span id="translatedtitle"><span class="hlt">Warm</span> Up with Skill.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Hoyle, R. J.; Smith, Robert F.</p> <p>1989-01-01</p> <p>Too little time is often spent on <span class="hlt">warm</span>-up activities in the school or recreation class. <span class="hlt">Warm</span>-ups are often perfunctory and unimaginative. Several suggestions are made for <span class="hlt">warm</span>-up activities that incorporate both previously learned and new skills, while preparing the body for more vigorous activity. (IAH)</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('https://www.ncbi.nlm.nih.gov/pubmed/24045424','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24045424"><span id="translatedtitle">Climate change and influenza: the likelihood of early and severe influenza seasons following warmer than average <span class="hlt">winters</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Towers, Sherry; Chowell, Gerardo; Hameed, Rasheed; Jastrebski, Matthew; Khan, Maryam; Meeks, Jonathan; Mubayi, Anuj; Harris, George</p> <p>2013-01-28</p> <p>The 2012-13 influenza season had an unusually early and severe start in the US, succeeding the record mild 2011-12 influenza season, which occurred during the fourth warmest <span class="hlt">winter</span> on record. Our analysis of climate and past US influenza epidemic seasons between 1997-98 to present indicates that <span class="hlt">warm</span> <span class="hlt">winters</span> tend to be followed by severe epidemics with early onset, and that these patterns are seen for both influenza A and B. We posit that fewer people are infected with influenza during <span class="hlt">warm</span> <span class="hlt">winters</span>, thereby leaving an unnaturally large fraction of susceptible individuals in the population going into the next season, which can lead to early and severe epidemics. In the event of continued global <span class="hlt">warming</span>, <span class="hlt">warm</span> <span class="hlt">winters</span> such as that of 2011-12 are expected to occur more frequently. Our results thus suggest that expedited manufacture and distribution of influenza vaccines after mild <span class="hlt">winters</span> has the potential to mitigate the severity of future influenza epidemics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMGC41G..06S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMGC41G..06S"><span id="translatedtitle">Understanding future changes in Northern Hemisphere <span class="hlt">winter</span> meridional wind and regional hydroclimate</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Simpson, I.; Seager, R.; Ting, M.; Shaw, T.</p> <p>2015-12-01</p> <p>A critical aspect of human-induced climate change is how it will affect climatological mean and <span class="hlt">extreme</span> precipitation around the world. To leading order, the increased ability of the atmosphere to hold moisture as it <span class="hlt">warms</span>, intensifies moisture transports, making subtropical dry regions drier and tropical and mid- to high latitude wet regions wetter. But regionally, precipitation change will also depend on how the atmospheric circulation responds to <span class="hlt">warming</span>. During Northern Hemisphere <span class="hlt">winter</span>, climate models predict a robust (in terms of structure) change in the stationary wave field that brings wetting southerlies to the west coast of North America and drying northerlies to interior southwest North America and the Mediterranean. Here, the underlying cause of this change is investigated. Stationary wave model experiments reaveal that the strengthening of the zonal wind in the sub-tropical upper troposphere is primarily responsible through it's influence on the character of intermediate scale stationary waves. A robust and easily understood model response to global <span class="hlt">warming</span> is, therefore, the prime cause and it should be expected to happen to some degree. However, there is considerable model diversity in the magnitude of the stationary wave response and almost 50% of the model spread over North America can be explained through this mechanistic understanding, allowing an improved estimate of where the real world will sit within the spectrum of model behavior. It is concluded that many models are likely overestimating the magnitude of this response and as a result, the wetting of the North American west coast and drying in the interior south west will likely be weaker than predicted by the majority of models and the multi-model mean. The implications of this for future predicted hydroclimate <span class="hlt">extremes</span> will also be discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24804439','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24804439"><span id="translatedtitle">Permafrost degradation stimulates carbon loss from experimentally <span class="hlt">warmed</span> tundra.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Natali, Susan M; Schuur, Edward A G; Webb, Elizabeth E; Pries, Caitlin E Hicks; Crummer, Kathryn G</p> <p>2014-03-01</p> <p>A large pool of organic carbon (C) has been accumulating in the Arctic for thousands of years because cold and waterlogged conditions have protected soil organic material from microbial decomposition. As the climate <span class="hlt">warms</span> this vast and frozen C pool is at risk of being thawed, decomposed, and released to the atmosphere as greenhouse gasses. At the same time, some C losses may be offset by <span class="hlt">warming</span>-mediated increases in plant productivity. Plant and microbial responses to <span class="hlt">warming</span> ultimately determine net C exchange from ecosystems, but the timing and magnitude of these responses remain uncertain. Here we show that experimental <span class="hlt">warming</span> and permafrost (ground that remains below 0 degrees C for two or more consecutive years) degradation led to a two-fold increase in net ecosystem C uptake during the growing season. However, <span class="hlt">warming</span> also enhanced <span class="hlt">winter</span> respiration, which entirely offset growing-season C gains. <span class="hlt">Winter</span> C losses may be even higher in response to actual climate <span class="hlt">warming</span> than to our experimental manipulations, and, in that scenario, could be expected to more than double overall net C losses from tundra to the atmosphere. Our results highlight the importance of <span class="hlt">winter</span> processes in determining whether tundra acts as a C source or sink, and demonstrate the potential magnitude of C release from the permafrost zone that might be expected in a warmer climate.</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 id="translatedtitle">The Tropical Western Hemisphere <span class="hlt">Warm</span> 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 tropical Western Hemisphere <span class="hlt">warm</span> pool (WHWP) of water warmer than 28.5oC. The WHWP is the second-largest tropical <span class="hlt">warm</span> pool on Earth. Unlike the Eastern Hemisphere <span class="hlt">warm</span> pool in the western Pacific, 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 Pacific, the Gulf of Mexico, the Caribbean, and the western tropical North Atlantic. It has a large seasonal cycle and its interannual fluctuations of area and intensity are significant. Surface heat fluxes <span class="hlt">warm</span> 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 Pacific 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 <span class="hlt">winter</span> preceding large <span class="hlt">warm</span> pool, there is an alteration of the Walker and Hadley circulation cells that serves as a "tropospheric bridge" for transferring Pacific ENSO effects to the Atlantic sector and inducing initial <span class="hlt">warming</span> of <span class="hlt">warm</span> pool. Associated with the <span class="hlt">warm</span> 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/2011ThApC.103...27H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011ThApC.103...27H"><span id="translatedtitle">Climatology of <span class="hlt">winter</span> transition days for the contiguous USA, 1951-2007</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hondula, David M.; Davis, Robert E.</p> <p>2011-01-01</p> <p>In middle and high latitudes, climate change could impact the frequency and characteristics of frontal passages. Although transitions between air masses are significant features of the general circulation that influence human activities and other surface processes, they are much more difficult to objectively identify than single variables like temperature or even <span class="hlt">extreme</span> events like fires, droughts, and floods. The recently developed Spatial Synoptic Classification (SSC) provides a fairly objective means of identifying frontal passages. In this research, we determine the specific meteorological patterns represented by the SSC's Transition category, a "catch-all" group that attempts to identify those days that cannot be characterized as a single, homogeneous air mass type. The result is a detailed transition climatology for the continental USA. We identify four subtypes of the Transition category based on intra-day sea level pressure change and dew point temperature change. Across the contiguous USA, most transition days are identified as cold fronts and <span class="hlt">warm</span> fronts during the <span class="hlt">winter</span> season. Among the two less common subtypes, transition days in which the dew point temperature and pressure both rise are more frequently observed across the western states, and days in which both variables fall are more frequently observed in coastal regions. The relative frequencies of wintertime <span class="hlt">warm</span> and cold fronts have changed over the period 1951-2007. Relative cold front frequency has significantly increased in the Northeast and Midwest regions, and <span class="hlt">warm</span> front frequencies have declined in the Midwest, Rocky Mountain, and Pacific Northwest regions. The overall shift toward cold fronts and away from <span class="hlt">warm</span> fronts across the northern USA arises from a combination of an enhanced ridge over western North America and a northward shift of storm tracks throughout the mid-latitudes. These results are consistent with projections of climate change associated with elevated greenhouse gas</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ERL....10i4024S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ERL....10i4024S"><span id="translatedtitle">Urban climate effects on <span class="hlt">extreme</span> temperatures in Madison, Wisconsin, USA</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schatz, Jason; Kucharik, Christopher J.</p> <p>2015-09-01</p> <p>As climate change increases the frequency and intensity of <span class="hlt">extreme</span> heat, cities and their urban heat island (UHI) effects are growing, as are the urban populations encountering them. These mutually reinforcing trends present a growing risk for urban populations. However, we have limited understanding of urban climates during <span class="hlt">extreme</span> temperature episodes, when additional heat from the UHI may be most consequential. We observed a historically hot summer and historically cold <span class="hlt">winter</span> using an array of up to 150 temperature and relative humidity sensors in and around Madison, Wisconsin, an urban area of population 402 000 surrounded by lakes and a rural landscape of agriculture, forests, wetlands, and grasslands. In the summer of 2012 (third hottest since 1869), Madison’s urban areas experienced up to twice as many hours ⩾32.2 °C (90 °F), mean July TMAX up to 1.8 °C higher, and mean July TMIN up to 5.3 °C higher than rural areas. During a record setting heat wave, dense urban areas spent over four consecutive nights above the National Weather Service nighttime heat stress threshold of 26.7 °C (80 °F), while rural areas fell below 26.7 °C nearly every night. In the <span class="hlt">winter</span> of 2013-14 (coldest in 35 years), Madison’s most densely built urban areas experienced up to 40% fewer hours ⩽-17.8 °C (0 °F), mean January TMAX up to 1 °C higher, and mean January TMIN up to 3 °C higher than rural areas. Spatially, the UHI tended to be most intense in areas with higher population densities. Temporally, both daytime and nighttime UHIs tended to be slightly more intense during more-<span class="hlt">extreme</span> heat days compared to average summer days. These results help us understand the climates for which cities must prepare in a <span class="hlt">warming</span>, urbanizing world.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002IJCli..22.1511G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002IJCli..22.1511G"><span id="translatedtitle">Climatological analysis of wintertime <span class="hlt">extreme</span> low temperatures in São Paulo City, Brazil: impact of sea-surface temperature anomalies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gonçalves, F. L. T.; Silva Dias, P. L.; Araújo, G. P.</p> <p>2002-10-01</p> <p>A diagnostic climatological study of <span class="hlt">winter</span> cold temperature <span class="hlt">extremes</span> in the Metropolitan Area of São Paulo (MASP) is presented. This diagnosis is based on temperature data collected at the Meteorological Station of Parque Estadual das Fontes do Ipiranga (IAG/USP) from 1950 to 2000. The persistence of synoptic and climatological patterns has been studied through principal component (PC) analysis and the results are compared with monthly anomalies in sea-surface temperature (SST) of the eastern Pacific and South Atlantic. The <span class="hlt">extreme</span> cold air temperatures, on a monthly basis, have shown no significant change since 1950. On the other hand, the mean monthly air temperatures have shown a slight <span class="hlt">warming</span> trend, in agreement with the South Atlantic Ocean <span class="hlt">warming</span> trend. The PC indicates significant loadings of two SST anomaly types: a cold anomaly of the South Atlantic Ocean, and a <span class="hlt">warm</span> anomaly off the southern Brazilian coast. The latter could also be responsible for some <span class="hlt">extreme</span> cold events (for daily minimum temperatures) in the MASP, and to a dominant westerly wind direction (southwest to northwest). Both the cold events and the westerly wind direction were evident in such <span class="hlt">winters</span> as 1953, 1975, 1978, 1981, and 1994. On the other hand, the cold mean monthly temperatures are very well correlated to a broad cold pool anomaly in the South Atlantic at around 25 to 35° S and 15 to 55° W - sometimes narrower (such as in 1979 and 1988), and sometimes broader (such as 1964 and 1990). Where there was a narrowing or a widening, the prevailing wind direction was from the south-southeast. Therefore, the conclusion of these results is that the SST anomalies in the South Atlantic Ocean have a dominant effect on the São Paulo <span class="hlt">winter</span> temperature climatology.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://elibrary.unm.edu/sora/Auk/v107n04/p0745-p0749.pdf','USGSPUBS'); return false;" href="http://elibrary.unm.edu/sora/Auk/v107n04/p0745-p0749.pdf"><span id="translatedtitle">American woodcock <span class="hlt">winter</span> distribution and fidelity to <span class="hlt">wintering</span> areas</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Diefenbach, D.R.; Derleth, E.L.; Vander Haegen, W.M.; Nichols, J.D.; Hines, J.E.</p> <p>1990-01-01</p> <p>We examined <span class="hlt">winter</span> distribution and fidelity to <span class="hlt">wintering</span> areas for the American Woodcock (Scolopax minor), which exhibits reversed, sexual size dimorphism. Band-recovery data revealed no difference in <span class="hlt">winter</span> distributions of different age/sex classes for woodcock from the same breeding areas. Similarly, band recoveries from woodcock banded on <span class="hlt">wintering</span> grounds revealed no difference in fidelity to <span class="hlt">wintering</span> sites. Males may <span class="hlt">winter</span> north of a latitude that is optimal for survival based on physiological considerations, but they gain a reproductive advantage if they are among the first to arrive on the breeding grounds. This may explain our results, which indicate males and females have similar distribution patterns during <span class="hlt">winter</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25035801','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25035801"><span id="translatedtitle">Local adaptations to frost in marginal and central populations of the dominant forest tree Fagus sylvatica L. as affected by temperature and <span class="hlt">extreme</span> drought in common garden experiments.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kreyling, Juergen; Buhk, Constanze; Backhaus, Sabrina; Hallinger, Martin; Huber, Gerhard; Huber, Lukas; Jentsch, Anke; Konnert, Monika; Thiel, Daniel; Wilmking, Martin; Beierkuhnlein, Carl</p> <p>2014-03-01</p> <p>Local adaptations to environmental conditions are of high ecological importance as they determine distribution ranges and likely affect species responses to climate change. Increased environmental stress (<span class="hlt">warming</span>, <span class="hlt">extreme</span> drought) due to climate change in combination with decreased genetic mixing due to isolation may lead to stronger local adaptations of geographically marginal than central populations. We experimentally observed local adaptations of three marginal and four central populations of Fagus sylvaticaL., the dominant native forest tree, to frost over <span class="hlt">winter</span> and in spring (late frost). We determined frost hardiness of buds and roots by the relative electrolyte leakage in two common garden experiments. The experiment at the cold site included a continuous <span class="hlt">warming</span> treatment; the experiment at the <span class="hlt">warm</span> site included a preceding summer drought manipulation. In both experiments, we found evidence for local adaptation to frost, with stronger signs of local adaptation in marginal populations. <span class="hlt">Winter</span> frost killed many of the potted individuals at the cold site, with higher survival in the <span class="hlt">warming</span> treatment and in those populations originating from colder environments. However, we found no difference in <span class="hlt">winter</span> frost tolerance of buds among populations, implying that bud survival was not the main cue for mortality. Bud late frost tolerance in April differed between populations at the <span class="hlt">warm</span> site, mainly because of phenological differences in bud break. Increased spring frost tolerance of plants which had experienced drought stress in the preceding summer could also be explained by shifts in phenology. Stronger local adaptations to climate in geographically marginal than central populations imply the potential for adaptation to climate at range edges. In times of climate change, however, it needs to be tested whether locally adapted populations at range margins can successfully adapt further to changing conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..1610644V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..1610644V"><span id="translatedtitle">Significant influences of global mean temperature and ENSO on <span class="hlt">extreme</span> rainfall over Southeast Asia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Villafuerte, Marcelino, II; Matsumoto, Jun</p> <p>2014-05-01</p> <p>Along with the increasing concerns on the consequences of global <span class="hlt">warming</span>, and the accumulating records of disaster related to heavy rainfall events in Southeast Asia, this study investigates whether a direct link can be detected between the rising global mean temperature, as well as the El Niño-Southern Oscillation (ENSO), and <span class="hlt">extreme</span> rainfall over the region. The maximum likelihood modeling that allows incorporating covariates on the location parameter of the generalized <span class="hlt">extreme</span> value (GEV) distribution is employed. The GEV model is fitted to annual and seasonal rainfall <span class="hlt">extremes</span>, which were taken from a high-resolution gauge-based gridded daily precipitation data covering a span of 57 years (1951-2007). Nonstationarities in <span class="hlt">extreme</span> rainfall are detected over the central parts of Indochina Peninsula, eastern coasts of central Vietnam, northwest of the Sumatra Island, inland portions of Borneo Island, and on the northeastern and southwestern coasts of the Philippines. These nonstationarities in <span class="hlt">extreme</span> rainfall are directly linked to near-surface global mean temperature and ENSO. In particular, the study reveals that a kelvin increase in global mean temperature anomaly can lead to an increase of 30% to even greater than 45% in annual maximum 1-day rainfall, which were observed pronouncedly over central Vietnam, southern coast of Myanmar, northwestern sections of Thailand, northwestern tip of Sumatra, central portions of Malaysia, and the Visayas island in central Philippines. Furthermore, a pronounced ENSO influence manifested on the seasonal maximum 1-day rainfall; a northward progression of 10%-15% drier condition over Southeast Asia as the El Niño develops from summer to <span class="hlt">winter</span> is revealed. It is important therefore, to consider the results obtained here for water resources management as well as for adaptation planning to minimize the potential adverse impact of global <span class="hlt">warming</span>, particularly on <span class="hlt">extreme</span> rainfall and its associated flood risk over the region</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.A41L..07L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.A41L..07L"><span id="translatedtitle">Surface Temperature Probability Distributions and <span class="hlt">Extremes</span> in the NARCCAP Hindcast Experiment: Evaluation Methodology and Metrics, Results, and Associated Atmospheric Mechanisms</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Loikith, P.; Waliser, D. E.; Kim, J.; Lee, H.; Lintner, B. R.; Neelin, J.; McGinnis, S. A.; Mattmann, C. A.; Mearns, L. O.</p> <p>2013-12-01</p> <p>Daily surface temperature probability distribution functions (PDFs) for a suite of regional climate model (RCM) hindcast experiments participating in the North American Regional Climate Change Assessment Program (NARCCAP) are evaluated against two state-of-the-art high resolution reanalysis products over North America. While all models exhibit some level of temperature bias throughout the PDF, the majority of models capture higher moment statistics like variance and skewness with reasonable fidelity in the <span class="hlt">winter</span>. More substantial disagreement exists in the simulation of the tails of the summer temperature distributions, with notable observational uncertainty, indicative of difficulty in properly simulating temperature <span class="hlt">extremes</span> here. To better understand the mechanisms behind model-reanalysis disagreement, potential mechanisms affecting PDF shape are evaluated, focusing on events in the tails of the distribution. Composite analysis is employed to investigate differences in atmospheric circulation patterns associated with <span class="hlt">extreme</span> temperature days at select locations where station data are available to reconcile reanalysis PDF uncertainty. In general, the models simulate large-scale atmospheric circulation patterns well where the shape of the PDF most resembles reanalysis, especially in the <span class="hlt">winter</span>. Summertime patterns tend to be smaller in scale and lower in magnitude where <span class="hlt">extreme</span> temperature occurrence may also be associated with local processes such as unusual soil moisture content and convective precipitation and cloudiness, introducing additional possibilities for model disagreement. From this comprehensive multi-model evaluation, it is possible to identify which models may be best suited to simulate temperature <span class="hlt">extremes</span> under global <span class="hlt">warming</span> conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..1513367O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..1513367O"><span id="translatedtitle">A late <span class="hlt">winter</span> arctic temperature record</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ólafsson, Haraldur; Ágústsson, Hálfdán</p> <p>2013-04-01</p> <p>In the afternoon of 29 March 2012, a temperature recording of 20.5 °C was made at Kvísker in Southeast-Iceland. This <span class="hlt">extreme</span> event is analysed and described by a numerical simulation. The analysis of the event leads to identification of the following important characteristics a) A <span class="hlt">warm</span> airmass b) A low level inversion and strong winds at mountain top level leading to an upstream blocking and yet strong downslope flow c) Weak winds (<2 m/s) leading to a superadiabatic surface layer d) Snow-free and dry soil for a low albedo and a high Bowen ratio Some of the above situations are infrequent, such as dry soil in March and <span class="hlt">warm</span> and strong foehn winds over the slopes in SE-Iceland, but calm at the same time at the weather station in question. The frequency of conditions for <span class="hlt">extreme</span> events of this kind in future climate scenarios will be explored.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22834382','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22834382"><span id="translatedtitle"><span class="hlt">Warming</span> modifies trophic cascades and eutrophication in experimental freshwater communities.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kratina, Pavel; Greig, Hamish S; Thompson, Patrick L; Carvalho-Pereira, Ticiana S A; Shurin, Jonathan B</p> <p>2012-06-01</p> <p>Climate <span class="hlt">warming</span> is occurring in concert with other anthropogenic changes to ecosystems. However, it is unknown whether and how <span class="hlt">warming</span> alters the importance of top-down vs. bottom-up control over community productivity and variability. We performed a 16-month factorial experimental manipulation of <span class="hlt">warming</span>, nutrient enrichment, and predator presence in replicated freshwater pond mesocosms to test their independent and interactive impacts. <span class="hlt">Warming</span> strengthened trophic cascades from fish to primary producers, and it decreased the impact of eutrophication on the mean and temporal variation of phytoplankton biomass. These impacts varied seasonally, with higher temperatures leading to stronger trophic cascades in <span class="hlt">winter</span> and weaker algae blooms under eutrophication in summer. Our results suggest that higher temperatures may shift the control of primary production in freshwater ponds toward stronger top-down and weaker bottom-up effects. The dampened temporal variability of algal biomass under eutrophication at higher temperatures suggests that <span class="hlt">warming</span> may stabilize some ecosystem processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013GeoRL..40.2091M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013GeoRL..40.2091M"><span id="translatedtitle">Recent <span class="hlt">warming</span> at Summit, Greenland: Global context 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>McGrath, Daniel; Colgan, William; Bayou, Nicolas; Muto, Atsuhiro; Steffen, Konrad</p> <p>2013-05-01</p> <p>at Summit, Greenland suggest that the annual mean near-surface air temperature increased at 0.09 ± 0.01°C/a over the 1982-2011 climatology period. This rate of <span class="hlt">warming</span>, six times the global average, places Summit in the 99th percentile of all globally observed <span class="hlt">warming</span> trends over this period. The rate of <span class="hlt">warming</span> at Summit is increasing over time. During the instrumental period (1987-2011), <span class="hlt">warming</span> has been greatest in the <span class="hlt">winter</span> season, although the implications of summer <span class="hlt">warming</span> are more acute. The annual maximum elevation of the equilibrium line and dry snow line has risen at 44 and 35 m/a over the past 15 and 18 years, respectively. Extrapolation of this observed trend now suggests, with 95% confidence intervals, that the dry snow facies of the Greenland Ice Sheet will inevitably transition to percolation facies. There is a 50% probability of this transition occurring by 2025.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=309994&keyword=put&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=78687768&CFTOKEN=38953102','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=309994&keyword=put&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=78687768&CFTOKEN=38953102"><span id="translatedtitle">Preliminary Evidence for the Amplification of Global <span class="hlt">Warming</span> in Shallow, Intertidal Estuarine Waters</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>Over the past 50 years, mean annual water temperature in northeastern U.S. estuaries has increased by approximately 1.2°C, with most of the <span class="hlt">warming</span> recorded in the <span class="hlt">winter</span> and early spring. We hypothesize that this <span class="hlt">warming</span> may be amplified in the shallow (<2m), nearshore portions ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22591333','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22591333"><span id="translatedtitle">Global <span class="hlt">warming</span> reduces plant reproductive output for temperate multi-inflorescence species on the Tibetan plateau.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Liu, Yinzhan; Mu, Junpeng; Niklas, Karl J; Li, Guoyong; Sun, Shucun</p> <p>2012-07-01</p> <p>• Temperature is projected to increase more during the <span class="hlt">winter</span> than during the summer in cold regions. The effects of <span class="hlt">winter</span> <span class="hlt">warming</span> on reproductive effort have not been examined for temperate plant species. • Here, we report the results of experimentally induced seasonal <span class="hlt">winter</span> <span class="hlt">warming</span> (0.4 and 2.4°C increases in growing and nongrowing seasons, respectively, using <span class="hlt">warmed</span> and ambient open-top chambers in a Tibetan Plateau alpine meadow) for nine indeterminate-growing species producing multiple (single-flowered or multi-flowered) inflorescences and three determinate-growing species producing single inflorescences after a 3-yr period of <span class="hlt">warming</span>. • <span class="hlt">Warming</span> reduced significantly flower number and seed production per plant for all nine multi-inflorescence species, but not for the three single-inflorescence species. <span class="hlt">Warming</span> had an insignificant effect on the fruit to flower number ratio, seed size and seed number per fruit among species. The reduction in seed production was largely attributable to the decline in flower number per plant. The flowering onset time was unaffected for nine of the 12 species. Therefore, the decline in flower production and seed production in response to <span class="hlt">winter</span> <span class="hlt">warming</span> probably reflects a physiological response (e.g. metabolic changes associated with flower production). • Collectively, the data indicate that global <span class="hlt">warming</span> may reduce flower and seed production for temperate herbaceous species and will probably have a differential effect on single- vs multi-inflorescence species.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1998GeoRL..25.3517S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1998GeoRL..25.3517S"><span id="translatedtitle">Polar stratospheric clouds: A high latitude <span class="hlt">warming</span> mechanism in an ancient greenhouse world</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sloan, L. Cirbus; Pollard, D.</p> <p></p> <p>The presence of water vapor clouds in the stratosphere produces <span class="hlt">warming</span> in excess of tropospheric greenhouse <span class="hlt">warming</span>, via radiative <span class="hlt">warming</span> in the lower stratosphere. The stratospheric clouds form only in regions of very low temperature and so the <span class="hlt">warming</span> produced by the clouds is concentrated in polar <span class="hlt">winter</span> regions. Results from a paleoclimate modeling study that includes idealized, prescribed polar stratospheric clouds (PSCs) show that the clouds cause up to 20°C of <span class="hlt">warming</span> at high latitude surfaces of the <span class="hlt">winter</span> hemisphere, with greatest impact in oceanic regions where sea ice is reduced. The modeled temperature response suggests that PSCs may have been a significant climate forcing factor for past time intervals associated with high concentrations of atmospheric methane. The clouds and associated <span class="hlt">warming</span> may help to explain long-standing discrepancies between model-produced paleotemperatures and geologic proxy temperature interpretations at high latitudes, a persistent problem in studies of ancient greenhouse climates.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.H43N..02W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.H43N..02W"><span id="translatedtitle">Investigating NARCCAP Precipitation <span class="hlt">Extremes</span> via Bivariate <span class="hlt">Extreme</span> Value Theory (Invited)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Weller, G. B.; Cooley, D. S.; Sain, S. R.; Bukovsky, M. S.; Mearns, L. O.</p> <p>2013-12-01</p> <p>We introduce methodology from statistical <span class="hlt">extreme</span> value theory to examine the ability of reanalysis-drive regional climate models to simulate past daily precipitation <span class="hlt">extremes</span>. Going beyond a comparison of summary statistics such as 20-year return values, we study whether the most <span class="hlt">extreme</span> precipitation events produced by climate model simulations exhibit correspondence to the most <span class="hlt">extreme</span> events seen in observational records. The extent of this correspondence is formulated via the statistical concept of tail dependence. We examine several case studies of <span class="hlt">extreme</span> precipitation events simulated by the six models of the North American Regional Climate Change Assessment Program (NARCCAP) driven by NCEP reanalysis. It is found that the NARCCAP models generally reproduce daily <span class="hlt">winter</span> precipitation <span class="hlt">extremes</span> along the Pacific coast quite well; in contrast, simulation of past daily summer precipitation <span class="hlt">extremes</span> in a central US region is poor. Some differences in the strength of <span class="hlt">extremal</span> correspondence are seen in the central region between models which employ spectral nudging and those which do not. We demonstrate how these techniques may be used to draw a link between <span class="hlt">extreme</span> precipitation events and large-scale atmospheric drivers, as well as to downscale <span class="hlt">extreme</span> precipitation simulated by a future run of a regional climate model. Specifically, we examine potential future changes in the nature of <span class="hlt">extreme</span> precipitation along the Pacific coast produced by the pineapple express (PE) phenomenon. A link between <span class="hlt">extreme</span> precipitation events and a "PE Index" derived from North Pacific sea-surface pressure fields is found. This link is used to study PE-influenced <span class="hlt">extreme</span> precipitation produced by a future-scenario climate model run.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006PrOce..70..346E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006PrOce..70..346E"><span id="translatedtitle">How are large western hemisphere <span class="hlt">warm</span> pools formed?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Enfield, David B.; Lee, Sang-Ki; Wang, Chunzai</p> <p>2006-08-01</p> <p>During the boreal summer the Western Hemisphere <span class="hlt">warm</span> pool (WHWP) stretches from the eastern North Pacific to the tropical North Atlantic and is a key feature of the climate of the Americas and Africa. In the summers following nine El Niño events during 1950-2000, there have been five instances of extraordinarily large <span class="hlt">warm</span> pools averaging about twice the climatological annual size. These large <span class="hlt">warm</span> pools have induced a strengthened divergent circulation aloft and have been associated with rainfall anomalies throughout the western hemisphere tropics and subtropics and with more frequent hurricanes. However, following four other El Niño events large <span class="hlt">warm</span> pools did not develop, such that the mere existence of El Niño during the boreal <span class="hlt">winter</span> does not provide the basis for predicting an anomalously large <span class="hlt">warm</span> pool the following summer. In this paper, we find consistency with the hypothesis that large <span class="hlt">warm</span> pools result from an anomalous divergent circulation forced by sea surface temperature (SST) anomalies in the Pacific, the so-called atmospheric bridge. We also find significant explanations for why large <span class="hlt">warm</span> pools do not always develop. If the El Niño event ends early in the eastern Pacific, the Pacific <span class="hlt">warm</span> anomaly lacks the persistence needed to force the atmospheric bridge and the Atlantic portion of the <span class="hlt">warm</span> pool remains normal. If SST anomalies in the eastern Pacific do not last much beyond February of the following year, then the eastern North Pacific portion of the <span class="hlt">warm</span> pool remains normal. The overall strength of the Pacific El Niño does not appear to be a critical factor. We also find that when conditions favor a developing atmospheric bridge and the <span class="hlt">winter</span> atmosphere over the North Atlantic conforms to a negative North Atlantic Oscillation (NAO) pattern (as in 1957-58 and 1968-69), the forcing is reinforced and the <span class="hlt">warm</span> pool is stronger. On the other hand, if a positive NAO pattern develops the <span class="hlt">warm</span> pool may remain normal even if other circumstances</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20170000976&hterms=Lee&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D30%26Ntt%3DLee%252C%2BIn','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20170000976&hterms=Lee&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D30%26Ntt%3DLee%252C%2BIn"><span id="translatedtitle">Analysis of the Warmest Arctic <span class="hlt">Winter</span>, 2015-2016</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cullather, Richard I.; Lim, Young-Kwon; Boisvert, Linette N.; Brucker, Ludovic; Lee, Jae N.; Nowicki, Sophie M. J.</p> <p>2016-01-01</p> <p>December through February 2015-2016 defines the warmest <span class="hlt">winter</span> season over the Arctic in the observational record. Positive 2m temperature anomalies were focused over regions of reduced sea ice cover in the Kara and Barents Seas and southwestern Alaska. A third region is found over the ice-covered central Arctic Ocean. The period is marked by a strong synoptic pattern which produced melting temperatures in close proximity to the North Pole in late December and anomalous high pressure near the Taymyr Peninsula. Atmospheric teleconnections from the Atlantic contributed to <span class="hlt">warming</span> over Eurasian high-latitude land surfaces, and El Niño-related teleconnections explain <span class="hlt">warming</span> over southwestern Alaska and British Columbia, while <span class="hlt">warm</span> anomalies over the central Arctic are associated with physical processes including the presence of enhanced atmospheric water vapor and an increased downwelling longwave radiative flux. Preconditioning of sea ice conditions by <span class="hlt">warm</span> temperatures affected the ensuing spring extent.</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://adsabs.harvard.edu/abs/2016GeoRL..4310808C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoRL..4310808C"><span id="translatedtitle">Analysis of the warmest Arctic <span class="hlt">winter</span>, 2015-2016</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cullather, Richard I.; Lim, Young-Kwon; Boisvert, Linette N.; Brucker, Ludovic; Lee, Jae N.; Nowicki, Sophie M. J.</p> <p>2016-10-01</p> <p>December through February 2015-2016 defines the warmest <span class="hlt">winter</span> season over the Arctic in the observational record. Positive 2 m temperature anomalies were focused over regions of reduced sea ice cover in the Kara and Barents Seas and southwestern Alaska. A third region is found over the ice-covered central Arctic Ocean. The period is marked by a strong synoptic pattern which produced melting temperatures in close proximity to the North Pole in late December and anomalous high pressure near the Taymyr Peninsula. Atmospheric teleconnections from the Atlantic contributed to <span class="hlt">warming</span> over Eurasian high-latitude land surfaces, and El Niño-related teleconnections explain <span class="hlt">warming</span> over southwestern Alaska and British Columbia, while <span class="hlt">warm</span> anomalies over the central Arctic are associated with physical processes including the presence of enhanced atmospheric water vapor and an increased downwelling longwave radiative flux. Preconditioning of sea ice conditions by <span class="hlt">warm</span> temperatures affected the ensuing spring extent.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1818437R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1818437R"><span id="translatedtitle"><span class="hlt">Extreme</span> conditions over Europe and North America: role of the Atlantic Multidecadal Variability</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ruprich-Robert, Yohan; Msadek, Rym; Delworth, Tom</p> <p>2016-04-01</p> <p>The Atlantic Multidecadal Variability (AMV) is the result and possibly the source of marked modulations of the climate over many areas of the globe. For instance, the relatively <span class="hlt">warm</span> and dry climate of North America throughout the 30-yr interval of 1931-60, during which the Dust Bowl and the 1950's drought occurred, has been linked to the concomitant <span class="hlt">warm</span> phase of the AMV. During this period relative <span class="hlt">warm</span> and wet conditions prevailed over Europe. After 1960, the Atlantic began to cool, and for almost three decades the North American climate turned wetter and cooler whereas Europe experienced cooler and dryer conditions. However, the shortness of the historical observations compared to the AMV period suggested by longer proxy (~60-80yr) does not allow to firmly conclude on the causal effect of the AMV. We use a model approach to isolate the causal role of the AMV on the occurrence of <span class="hlt">extreme</span> events over Europe and North America. We present experiments based on two GFDL global climate models, a low resolution version, CM2.1 and a higher resolution model for the atmospheric component, FLOR. In both model experiments sea surface temperatures in the North Atlantic sector are restored to the observed AMV pattern, while the other basins are left fully coupled. In order to explore and robustly isolate the AMV impacts on <span class="hlt">extreme</span> events, we use large ensemble simulations (100 members for CM2.1 and 50 for FLOR) that we run for 20 years. We find that a positive phase of the AMV increases the frequency of occurrence of drought over North America and of <span class="hlt">extremely</span> cold/<span class="hlt">warm</span> conditions over Northern/Central Europe during <span class="hlt">winter</span>/summer. Interestingly, we find that the AMV impacts on these <span class="hlt">extreme</span> conditions are modulated by the Pacific response to the AMV itself. Members that develop a weak Pacific response show more <span class="hlt">extreme</span> events over Europe whereas those that develop a strong Pacific response show more <span class="hlt">extreme</span> events over North America.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22371563','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22371563"><span id="translatedtitle">Impact of declining Arctic sea ice on <span class="hlt">winter</span> snowfall.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Liu, Jiping; Curry, Judith A; Wang, Huijun; Song, Mirong; Horton, Radley M</p> <p>2012-03-13</p> <p>While the Arctic region has been <span class="hlt">warming</span> strongly in recent decades, anomalously large snowfall in recent <span class="hlt">winters</span> has affected large parts of North America, Europe, and east Asia. Here we demonstrate that the decrease in autumn Arctic sea ice area is linked to changes in the <span class="hlt">winter</span> Northern Hemisphere atmospheric circulation that have some resemblance to the negative phase of the <span class="hlt">winter</span> Arctic oscillation. However, the atmospheric circulation change linked to the reduction of sea ice shows much broader meridional meanders in midlatitudes and clearly different interannual variability than the classical Arctic oscillation. This circulation change results in more frequent episodes of blocking patterns that lead to increased cold surges over large parts of northern continents. Moreover, the increase in atmospheric water vapor content in the Arctic region during late autumn and <span class="hlt">winter</span> driven locally by the reduction of sea ice provides enhanced moisture sources, supporting increased heavy snowfall in Europe during early <span class="hlt">winter</span> and the northeastern and midwestern United States during <span class="hlt">winter</span>. We conclude that the recent decline of Arctic sea ice has played a critical role in recent cold and snowy <span class="hlt">winters</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=warmup&pg=6&id=EJ601591','ERIC'); return false;" href="http://eric.ed.gov/?q=warmup&pg=6&id=EJ601591"><span id="translatedtitle"><span class="hlt">Warm</span>-Up Activities.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Mingguang, Yang</p> <p>1999-01-01</p> <p>Discusses how <span class="hlt">warm</span>-up activities can help to make the English-as-a-foreign-language classroom a lively and interesting place. <span class="hlt">Warm</span>-up activities are games carried out at the beginning of each class to motivate students to make good use of class time. (Author/VWL)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=global+AND+warming+AND+marine+AND+environment&id=EJ412301','ERIC'); return false;" href="http://eric.ed.gov/?q=global+AND+warming+AND+marine+AND+environment&id=EJ412301"><span id="translatedtitle">Global <span class="hlt">Warming</span> Trends.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Jones, Philip D.; Wigley, Tom M. L.</p> <p>1990-01-01</p> <p>Results from the analysis of land and marine records from the past century are presented. It is indicated that the planet earth has <span class="hlt">warmed</span> about one-half of a degree celsius. The uncertainty of these measurements and future <span class="hlt">warming</span> trends are discussed. (CW)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1237543-changes-concurrent-precipitation-temperature-extremes','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1237543-changes-concurrent-precipitation-temperature-extremes"><span id="translatedtitle">Changes in Concurrent Precipitation and Temperature <span class="hlt">Extremes</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Hao, Zengchao; AghaKouchak, Amir; Phillips, Thomas J.</p> <p>2013-08-01</p> <p>While numerous studies have addressed changes in climate <span class="hlt">extremes</span>, analyses of concurrence of climate <span class="hlt">extremes</span> are scarce, and climate change effects on joint <span class="hlt">extremes</span> are rarely considered. This study assesses the occurrence of joint (concurrent) monthly continental precipitation and temperature <span class="hlt">extremes</span> in Climate Research Unit (CRU) and University of Delaware (UD) observations, and in 13 Coupled Model Intercomparison Project Phase 5 (CMIP5) global climate simulations. Moreover, the joint occurrences of precipitation and temperature <span class="hlt">extremes</span> simulated by CMIP5 climate models are compared with those derived from the CRU and UD observations for <span class="hlt">warm</span>/wet, <span class="hlt">warm</span>/dry, cold/wet, and cold/dry combinations of joint <span class="hlt">extremes</span>.more » The number of occurrences of these four combinations during the second half of the 20th century (1951–2004) is assessed on a common global grid. CRU and UD observations show substantial increases in the occurrence of joint <span class="hlt">warm</span>/dry and <span class="hlt">warm</span>/wet combinations for the period 1978–2004 relative to 1951–1977. The results show that with respect to the sign of change in the concurrent <span class="hlt">extremes</span>, the CMIP5 climate model simulations are in reasonable overall agreement with observations. The results reveal notable discrepancies between regional patterns and the magnitude of change in individual climate model simulations relative to the observations of precipitation and temperature.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1237543','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1237543"><span id="translatedtitle">Changes in Concurrent Precipitation and Temperature <span class="hlt">Extremes</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hao, Zengchao; AghaKouchak, Amir; Phillips, Thomas J.</p> <p>2013-08-01</p> <p>While numerous studies have addressed changes in climate <span class="hlt">extremes</span>, analyses of concurrence of climate <span class="hlt">extremes</span> are scarce, and climate change effects on joint <span class="hlt">extremes</span> are rarely considered. This study assesses the occurrence of joint (concurrent) monthly continental precipitation and temperature <span class="hlt">extremes</span> in Climate Research Unit (CRU) and University of Delaware (UD) observations, and in 13 Coupled Model Intercomparison Project Phase 5 (CMIP5) global climate simulations. Moreover, the joint occurrences of precipitation and temperature <span class="hlt">extremes</span> simulated by CMIP5 climate models are compared with those derived from the CRU and UD observations for <span class="hlt">warm</span>/wet, <span class="hlt">warm</span>/dry, cold/wet, and cold/dry combinations of joint <span class="hlt">extremes</span>. The number of occurrences of these four combinations during the second half of the 20th century (1951–2004) is assessed on a common global grid. CRU and UD observations show substantial increases in the occurrence of joint <span class="hlt">warm</span>/dry and <span class="hlt">warm</span>/wet combinations for the period 1978–2004 relative to 1951–1977. The results show that with respect to the sign of change in the concurrent <span class="hlt">extremes</span>, the CMIP5 climate model simulations are in reasonable overall agreement with observations. The results reveal notable discrepancies between regional patterns and the magnitude of change in individual climate model simulations relative to the observations of precipitation and temperature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=insulation&pg=7&id=EJ307514','ERIC'); return false;" href="http://eric.ed.gov/?q=insulation&pg=7&id=EJ307514"><span id="translatedtitle">Teaching Ecology in <span class="hlt">Winter</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Clearing: Nature and Learning in the Pacific Northwest, 1984</p> <p>1984-01-01</p> <p>Presents ideas for teaching ecology in the <span class="hlt">winter</span>. Suggested topic areas or units include snow insulation and density, snowflakes and snow crystals, goldenrod galls, bird behavior, survival techniques, bacteriology and decomposition, trees and keying, biomass and productivity, pollution, and soil organisms. A sample student activity sheet is…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=northern+AND+lights&pg=7&id=EJ334897','ERIC'); return false;" href="http://eric.ed.gov/?q=northern+AND+lights&pg=7&id=EJ334897"><span id="translatedtitle">Mammals in <span class="hlt">Winter</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Wapner, Suzanne</p> <p>1985-01-01</p> <p>Mammals that tolerate the <span class="hlt">winter</span> cold and stay active all year exploit the harsh northern climate to their advantage. By simple experiments and observation you can better understand their adaptations which include furry bodies, snowshoe feet, extra blubber, light coloration, and strategically distributed food caches. (JHZ)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3291389','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3291389"><span id="translatedtitle">Influenza, <span class="hlt">Winter</span> Olympiad, 2002</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Rubin, Michael A.; Samore, Matthew H.; Lopansri, Bert; Lahey, Timothy; McGuire, Heather L.; Winthrop, Kevin L.; Dunn, James J.; Willick, Stuart E.; Vosters, Randal L.; Waeckerle, Joseph F.; Carroll, Karen C.; Gwaltney, Jack M.; Hayden, Frederick G.; Elstad, Mark R.; Sande, Merle A.</p> <p>2006-01-01</p> <p>Prospective surveillance for influenza was performed during the 2002 Salt Lake City <span class="hlt">Winter</span> Olympics. Oseltamivir was administered to patients with influenzalike illness and confirmed influenza, while their close contacts were given oseltamivir prophylactically. Influenza A/B was diagnosed in 36 of 188 patients, including 13 athletes. Prompt management limited the spread of this outbreak. PMID:16494733</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=dreaming&pg=4&id=EJ755597','ERIC'); return false;" href="http://eric.ed.gov/?q=dreaming&pg=4&id=EJ755597"><span id="translatedtitle"><span class="hlt">Winter</span> Playscape Dreaming</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Keeler, Rusty</p> <p>2006-01-01</p> <p><span class="hlt">Winter</span>, like all seasons, adds a new sense of mystery and discovery to the world of young children. It is the time when they can study snowflakes, find icicles, or observe the birds that share their yards. This article presents ideas and suggestions on how to plan a playscape. A playscape is a man-made seasonal playground for young children. It…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016cosp...41E1726S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016cosp...41E1726S"><span id="translatedtitle">Impact of <span class="hlt">winter</span> cooling on the northern part of the Black Sea.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Savchenko, Anatolii</p> <p>2016-07-01</p> <p>Climate change in the future may have a negative impact on many countries due to the increasing surface temperature and sea level rise. Probably, unprecedented largest positive trend of surface temperature, which observed since the mid XX century, has associated with increasing human activities around the world. Moreover, this <span class="hlt">warming</span> will continue in this century, and at the end of the XXI century will be 2 - 5 ºC. Thus, investigation and monitoring of current climate are very important and necessary tasks. Regional model data (downscaling) and satellite data are used, because of underdeveloped network of meteorological stations in the northern part of the Black Sea region. Experiment of downscaling was carried out for the Black Sea region with a high spatial resolution of 0.22° x 0.22° for 1958 - 2007(daily values). For the Black Sea were also used satellite data of sea surface temperature(SST) from MyOcean-2 Project, which CNR(Rome) has reprocessed Pathfinder V5.2 (PFV52) AVHRR data over period 1981 - 2012 with daily gap-free maps (L4) at the original PFV52 resolution at 0.04° x 0.04°. Correlation between satellite SST and surface temperature from regional model climate are amounted 0,99. Thus, surface temperature of model and satellite data for the Black Sea is much correlated between yourself. The following integral characteristics of the Black Sea are referred to the area of sea limited by the 44 - 47º N and 28 - 34º E. Maximum cooling of the north-western part of the Black Sea in <span class="hlt">winter</span> is occurs after invasion of cold air across the northern border of the basin. In addition, this water area is also interesting in the presence of her huge oil and gas reserves, as well as the construction of liquefied gas (crude oil) terminals. The maximum values of total heat flux (sensible + latent heat fluxes= Q) corresponding to the minimum values of SST are observed during the periods of the negative phase of the NAO. Besides, fluxes with <span class="hlt">extreme</span> days P (Q) = 95</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/361682','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/361682"><span id="translatedtitle">Establishing native <span class="hlt">warm</span> season grasses on Eastern Kentucky strip mines</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Barnes, T.G.; Larkin, J.L.; Arnett, M.B.</p> <p>1998-12-31</p> <p>The authors evaluated various methods of establishing native <span class="hlt">warm</span> season grasses on two reclaimed Eastern Kentucky mines from 1994--1997. Most current reclamation practices incorporate the use of tall fescue (Festuca arundinacea) and other cool-season grasses/legumes that provide little wildlife habitats. The use of native <span class="hlt">warm</span> season grasses will likely improve wildlife habitat on reclaimed strip mines. Objectives of this study were to compare the feasibility of establishing these grasses during fall, <span class="hlt">winter</span>, or spring using a native rangeland seeder or hydroseeding; a fertilizer application at planting; or cold-moist stratification prior to hydroseeding. Vegetative cover, bare ground, species richness, and biomass samples were collected at the end of each growing season. Native <span class="hlt">warm</span> season grass plantings had higher plant species richness compared to cool-season reclamation mixtures. There was no difference in establishment of native <span class="hlt">warm</span> season grasses as a result of fertilization or seeding technique. <span class="hlt">Winter</span> native <span class="hlt">warm</span> season grass plantings were failures and cold-moist stratification did not increase plant establishment during any season. As a result of a drought during 1997, both cool-season and <span class="hlt">warm</span> season plantings were failures. Cool-season reclamation mixtures had significantly more vegetative cover and biomass compared to native <span class="hlt">warm</span> season grass mixtures and the native <span class="hlt">warm</span> season grass plantings did not meet vegetative cover requirements for bond release. Forbs and legumes that established well included pale purple coneflower (Echinacea pallida), lance-leaf coreopsis (Coreopsis lanceolata), round-headed lespedeza (Lespedeza capitata), partridge pea (Cassia fasiculata), black-eyed susan (Rudbeckia hirta), butterfly milkweed (Asclepias tuberosa), and bergamot (Monarda fistulosa). Results from two demonstration plots next to research plots indicate it is possible to establish native <span class="hlt">warm</span> season grasses on Eastern Kentucky strip mines for wildlife habitat.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/15009836','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/15009836"><span id="translatedtitle"><span class="hlt">Warm</span> Dense Matter: An Overview</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kalantar, D H; Lee, R W; Molitoris, J D</p> <p>2004-04-21</p> <p>This document provides a summary of the ''LLNL Workshop on <span class="hlt">Extreme</span> States of Materials: <span class="hlt">Warm</span> Dense Matter to NIF'' which was held on 20, 21, and 22 February 2002 at the Wente Conference Center in Livermore, CA. The <span class="hlt">warm</span> dense matter regime, the transitional phase space region between cold material and hot plasma, is presently poorly understood. The drive to understand the nature of matter in this regime is sparking scientific activity worldwide. In addition to pure scientific interest, finite temperature dense matter occurs in the regimes of interest to the SSMP (Stockpile Stewardship Materials Program). So that obtaining a better understanding of WDM is important to performing effective experiments at, e.g., NIF, a primary mission of LLNL. At this workshop we examined current experimental and theoretical work performed at, and in conjunction with, LLNL to focus future activities and define our role in this rapidly emerging research area. On the experimental front LLNL plays a leading role in three of the five relevant areas and has the opportunity to become a major player in the other two. Discussion at the workshop indicated that the path forward for the experimental efforts at LLNL were two fold: First, we are doing reasonable baseline work at SPLs, HE, and High Energy Lasers with more effort encouraged. Second, we need to plan effectively for the next evolution in large scale facilities, both laser (NIF) and Light/Beam sources (LCLS/TESLA and GSI) Theoretically, LLNL has major research advantages in areas as diverse as the thermochemical approach to <span class="hlt">warm</span> dense matter equations of state to first principles molecular dynamics simulations. However, it was clear that there is much work to be done theoretically to understand <span class="hlt">warm</span> dense matter. Further, there is a need for a close collaboration between the generation of verifiable experimental data that can provide benchmarks of both the experimental techniques and the theoretical capabilities. The conclusion of this</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002EGSGA..27.1420P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002EGSGA..27.1420P"><span id="translatedtitle">Impacts of Climate Change On The Occurrence of <span class="hlt">Extreme</span> Events: The Mice Project</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Palutikof, J. P.; Mice Team</p> <p></p> <p>It is widely accepted that climate change due to global <span class="hlt">warming</span> will have substan- tial impacts on the natural environment, and on human activities. Furthermore, it is increasingly recognized that changes in the severity and frequency of <span class="hlt">extreme</span> events, such as windstorm and flood, are likely to be more important than changes in the average climate. The EU-funded project MICE (Modelling the Impacts of Climate <span class="hlt">Extremes</span>) commenced in January 2002. It seeks to identify the likely changes in the occurrence of <span class="hlt">extremes</span> of rainfall, temperature and windstorm due to global <span class="hlt">warm</span>- ing, using information from climate models as a basis, and to study the impacts of these changes in selected European environments. The objectives are: a) to evaluate, by comparison with gridded and station observations, the ability of climate models to successfully reproduce the occurrence of <span class="hlt">extremes</span> at the required spatial and temporal scales. b) to analyse model output with respect to future changes in the occurrence of <span class="hlt">extremes</span>. Statistical analyses will determine changes in (i) the return periods of ex- tremes, (ii) the joint probability of <span class="hlt">extremes</span> (combinations of damaging events such as windstorm followed by heavy rain), (iii) the sequential behaviour of <span class="hlt">extremes</span> (whether events are well-separated or clustered) and (iv) the spatial patterns of <span class="hlt">extreme</span> event occurrence across Europe. The range of uncertainty in model predictions will be ex- plored by analysing changes in model experiments with different spatial resolutions and forcing scenarios. c) to determine the impacts of the predicted changes in <span class="hlt">extremes</span> occurrence on selected activity sectors: agriculture (Mediterranean drought), commer- cial forestry and natural forest ecosystems (windstorm and flood in northern Europe, fire in the Mediterranean), energy use (temperature <span class="hlt">extremes</span>), tourism (heat stress and Mediterranean beach holidays, changes in the snow pack and <span class="hlt">winter</span> sports ) and civil protection/insurance (windstorm and flood</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.3422B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.3422B"><span id="translatedtitle">Magnitude and pattern of Arctic <span class="hlt">warming</span> governed by the seasonality of radiative forcing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bintanja, Richard; Krikken, Folmer</p> <p>2015-04-01</p> <p>Observed and projected climate <span class="hlt">warming</span> is strongest in the Arctic regions, and maximum in autumn/<span class="hlt">winter</span>. Attempts to explain this feature have focused primarily on identifying the associated climate feedbacks, particularly the ice-albedo and lapse-rate feedbacks. However, the impact of seasonally varying climate forcing has not been identified and quantified. Here we use a state-of-the-art global climate model in idealized seasonal forcing simulations to show that Arctic <span class="hlt">warming</span> is very sensitive to the season in which the radiative forcing occurs. More specifically, Arctic <span class="hlt">warming</span> and sea ice decline (especially in <span class="hlt">winter</span>) are particularly sensitive to forcing in spring, during which the energy is effectively 'absorbed' by the ocean (through sea ice melt and ocean <span class="hlt">warming</span>, amplified by the ice-albedo feedback) and consequently released to the lower atmosphere in autumn and <span class="hlt">winter</span>, mainly along the sea ice periphery. In contrast, wintertime radiative forcing yields a more evenly distributed <span class="hlt">winter</span> <span class="hlt">warming</span>, which, surprisingly, in certain regions is even smaller than that due to spring forcing. The dependence of the magnitude and pattern of Arctic <span class="hlt">warming</span> on the seasonality of the climate forcing has important implications in terms of projected increases in anthropogenic forcing. For instance, shipping-induced emissions such as those of black carbon are projected to peak in the ice-free summer and will thereby exert a comparatively strong impact on Arctic <span class="hlt">warming</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ThApC.123..473F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ThApC.123..473F"><span id="translatedtitle">Recent changes of temperature <span class="hlt">extremes</span> over Italy: an index-based analysis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fioravanti, Guido; Piervitali, Emanuela; Desiato, Franco</p> <p>2016-02-01</p> <p>The assessment of climate change impacts requires updated estimates of the tendencies in temperature <span class="hlt">extremes</span>. With the objective of studying recent variations in frequency and intensity of temperature <span class="hlt">extremes</span> over Italy, a collection of daily minimum and maximum temperature time series was selected for the calculation of a set of indices recommended by the Expert Team on Climate Change Detection and Indices (ETCCDI). The trend of each index was investigated through a non-parametric statistical analysis over the last half-century (1961-2011), and its spatial variability was illustrated through trend maps. Mean national-scale trends were also assessed at annual and seasonal level. The results show that mean annual series exhibit a general <span class="hlt">warming</span> tendency from 1961 to 2011, with significant trends for summer days, tropical nights, heat waves, and percentile-based indices at most stations, with <span class="hlt">warming</span> trends more pronounced in summer and spring and weaker in <span class="hlt">winter</span> and autumn. As a changepoint was identified in 1977 for the minimum ( T min) and maximum temperature ( T max) Italian annual series, the trend analysis was also performed for the two sub-periods 1961-1977 and 1978-2011. Non-significant "cooling" trends characterize the sub-period 1961-1977, while significant "<span class="hlt">warming</span>" trends were identified over the period 1978-2011. This study updates previous research in the extent of time series, in the number of indices and in the approach followed for their analysis, providing useful information for evaluating the impacts of temperature <span class="hlt">extremes</span> in the context of a changing climate in Italy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ready.gov/heat','NIH-MEDLINEPLUS'); return false;" href="https://www.ready.gov/heat"><span id="translatedtitle"><span class="hlt">Extreme</span> Heat</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... Emergencies Biological Threats Chemical Threats Cyber Incident Drought Earthquakes <span class="hlt">Extreme</span> Heat Explosions Floods Hazardous Materials Incidents Home ... Emergencies Biological Threats Chemical Threats Cyber ... Heat Explosions Floods Hazardous Materials Incidents Home ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.B31D0596S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.B31D0596S"><span id="translatedtitle">A Pan-arctic Survey about the Meaning of <span class="hlt">Winter</span> Respiration in Northern High Latitudes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Selbmann, A. K.; Natali, S.</p> <p>2015-12-01</p> <p>The arctic is <span class="hlt">warming</span> at twice the rate of the rest of the planet, with the greatest <span class="hlt">warming</span> occurring during the <span class="hlt">winter</span> months. Despite the cold temperatures during the <span class="hlt">winter</span>, microbial activity continues and leads to a release of soil carbon during a criticial period when plant uptake has ceased. Due to the <span class="hlt">warming</span> climate, huge pools of carbon stored in permafrost soils are expected to be released to the atmosphere. To identify the annual carbon balance of arctic ecosystems and potential impacts caused by a rise in temperatures, understanding the magnitude of <span class="hlt">winter</span> respiration is essential. In order to refine current and future estimates of carbon loss from permafrost ecosystems, we conducted a pan-arctic synthesis of <span class="hlt">winter</span> respiration from northern high latitude regions. We examined differences in cumulative <span class="hlt">winter</span> respiration among permafrost zones, biomes, ecosystem types, and effects of measurement method on <span class="hlt">winter</span> respiration estimates. We also examined effect of air temperature and precipitation (Worldclim database) on rates of <span class="hlt">winter</span> respiration. The database contained 169 measurement points from 46 study sites located throughout the permafrost zones. We found that 21.6 % of annual respiration is happening during non-growing season, which can shift ecosystems from annual sinks during the growing season to net sources of carbon on an annual basis. Across studies, the average carbon loss during the <span class="hlt">winter</span> was 66 g CO2-C. There was a strong relationship between mean annual air temperature and <span class="hlt">winter</span> respiration, and lower respiration in continuous compared to discontinuous permafrost zones and northern areas without permafrost. The present results clarify the contribution of <span class="hlt">winter</span> respiration to annual carbon balance and show the sensitivity of carbon release to rising temperatures in northern high latitudes. These results suggest that permafrost degradation and increased temperature will lead to a higher release of carbon from the Arctic in wintertime</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26043384','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26043384"><span id="translatedtitle"><span class="hlt">Warm</span> autoimmune hemolytic anemia.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Naik, Rakhi</p> <p>2015-06-01</p> <p><span class="hlt">Warm</span> autoimmune hemolytic anemia (AIHA) is defined as the destruction of circulating red blood cells (RBCs) in the setting of anti-RBC autoantibodies that optimally react at 37°C. The pathophysiology of disease involves phagocytosis of autoantibody-coated RBCs in the spleen and complement-mediated hemolysis. Thus far, treatment is aimed at decreasing autoantibody production with immunosuppression or reducing phagocytosis of affected cells in the spleen. The role of complement inhibitors in <span class="hlt">warm</span> AIHA has not been explored. This article addresses the diagnosis, etiology, and treatment of <span class="hlt">warm</span> AIHA and highlights the role of complement in disease pathology.</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('http://adsabs.harvard.edu/abs/2014AGUFM.B41C0046D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.B41C0046D"><span id="translatedtitle">Ecosystem Greenhouse Gas Fluxes Respond Directly to Weather Not Climate: A Case Study on the Relationship of Global Atmospheric Circulation, Foehn Frequency, and <span class="hlt">Winter</span> Weather to Northern Alps Regional Grassland Phenology and Carbon Cycling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Desai, A. R.; Wohlfahrt, G.; Zeeman, M. J.; Katata, G.; Mauder, M.; Schmid, H. P. E.</p> <p>2014-12-01</p> <p>The impact of climate change on regional ecosystem structure and biogeochemical cycling has two important aspects that require better elaboration to improve projections of these effects. The first is that ecosystems don't respond directly to climate, but indirectly via frequency and occurrence of weather systems, which are driven by climatic shifts in global circulation and radiative processes. The second is that many responses of ecosystems to these weather patterns and <span class="hlt">extremes</span> are lagged in time. Here, we examine these aspects for northern Alpine grasslands. Long-term eddy covariance flux tower and phenology observations in Austria and Germany and biophysical models reveal a strong influence of <span class="hlt">winter</span> air temperature, snowfall, and snowmelt frequency on <span class="hlt">winter</span> grass mortality and spring grassland carbon uptake. Further, the mode of climate variability that drives <span class="hlt">winter</span> air temperature and snow depth patterns is primarily the frequency of strong regional southerly Foehn flow that promotes <span class="hlt">warm</span>, dry conditions in <span class="hlt">winter</span>. Finally, we demonstrate that much of the interannual variance in Foehn frequency and southerly flow is driven by statistics and climatic trends of 500 hPa pressure patterns in Greenland, part of the Arctic Oscillation. However, a few years, including the unusually <span class="hlt">warm</span> and dry <span class="hlt">winter</span> of 2013-2014 appear to have secondary, possibly local thermotopographic circulation factors that promoted its weather conditions regionally, which also included primarily cool and wet conditions in northern Europe and the southern Alps. These findings demonstrate that the regional response of ecosystems to climate change is modulated by how large-scale circulation patterns influence local meteorology and topographic flows both during and outside the growing season and provides a framework for future assessment and climate model improvements of linkages of climate change, weather patterns, and ecosystem responses.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/7015600','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/7015600"><span id="translatedtitle">A successful forecast of an El Nino <span class="hlt">winter</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kerr, R.A.</p> <p>1992-01-24</p> <p>This year, for the first time, weather forecasters used signs of a <span class="hlt">warming</span> in the tropical Pacific as the basis for a long-range prediction of <span class="hlt">winter</span> weather patterns across the United States. Now forecasters are talking about the next step: stretching the lead time for such forecasts by a year or more. That seems feasible because although this Pacific <span class="hlt">warming</span> was unmistakable by the time forecasters at the National Weather Service's Climate Analysis Center (CAC) in Camp Springs, Maryland, issued their <span class="hlt">winter</span> forecast, the El Nino itself had been predicted almost 2 years in advance by a computer model. Next time around, the CAC may well be listening to the modelers and predicting El Nino-related patterns of warmth and flooding seasons in advance.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED357939.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED357939.pdf"><span id="translatedtitle"><span class="hlt">Winter</span> Wilderness Travel and Camping.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Gilchrest, Norman</p> <p></p> <p>Knowledge and skill are needed for safe and enjoyable travel and camping in the wilderness in <span class="hlt">winter</span>. The beauty of snow and ice, reduced human use, and higher tolerance of animals toward humans make the wilderness attractive during <span class="hlt">winter</span>. The uniqueness of <span class="hlt">winter</span> travel presents several challenges that are not present in other seasons. Safety is…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012PhDT.......226L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012PhDT.......226L"><span id="translatedtitle">Characteristics of atmospheric circulation patterns associated with <span class="hlt">extreme</span> temperatures over North America in observations and climate models</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Loikith, Paul C.</p> <p></p> <p>Motivated by a desire to understand the physical mechanisms involved in future anthropogenic changes in <span class="hlt">extreme</span> temperature events, the key atmospheric circulation patterns associated with <span class="hlt">extreme</span> daily temperatures over North America in the current climate are identified. Several novel metrics are used to systematically identify and describe these patterns for the entire continent. The orientation, physical characteristics, and spatial scale of these circulation patterns vary based on latitude, season, and proximity to important geographic features (i.e., mountains, coastlines). The anomaly patterns associated with <span class="hlt">extreme</span> cold events tend to be similar to, but opposite in sign of, those associated with <span class="hlt">extreme</span> <span class="hlt">warm</span> events, especially within the westerlies, and tend to scale with temperature in the same locations. The influence of the Pacific North American (PNA) pattern, the Northern Annular Mode (NAM), and the El Niño-Southern Oscillation (ENSO) on <span class="hlt">extreme</span> temperature days and months shows that associations between <span class="hlt">extreme</span> temperatures and the PNA and NAM are stronger than associations with ENSO. In general, the association with <span class="hlt">extremes</span> tends to be stronger on monthly than daily time scales. <span class="hlt">Extreme</span> temperatures are associated with the PNA and NAM in locations typically influenced by these circulation patterns; however many <span class="hlt">extremes</span> still occur on days when the amplitude and polarity of these patterns do not favor their occurrence. In <span class="hlt">winter</span>, synoptic-scale, transient weather disturbances are important drivers of <span class="hlt">extreme</span> temperature days; however these smaller-scale events are often concurrent with amplified PNA or NAM patterns. Associations are weaker in summer when other physical mechanisms affecting the surface energy balance, such as anomalous soil moisture content, are associated with <span class="hlt">extreme</span> temperatures. Analysis of historical runs from seventeen climate models from the CMIP5 database suggests that most models simulate realistic circulation patterns</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=dinosaur&pg=5&id=EJ658270','ERIC'); return false;" href="http://eric.ed.gov/?q=dinosaur&pg=5&id=EJ658270"><span id="translatedtitle"><span class="hlt">Warm</span> and Cool Dinosaurs.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Mannlein, Sally</p> <p>2001-01-01</p> <p>Presents an art activity in which first grade students draw dinosaurs in order to learn about the concept of <span class="hlt">warm</span> and cool colors. Explains how the activity also helped the students learn about the concept of distance when drawing. (CMK)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150000726','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150000726"><span id="translatedtitle">Reconciling <span class="hlt">Warming</span> Trends</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Schmidt, Gavin A.; Shindell, Drew T.; Tsigaridis, Konstantinos</p> <p>2014-01-01</p> <p>Climate models projected stronger <span class="hlt">warming</span> over the past 15 years than has been seen in observations. Conspiring factors of errors in volcanic and solar inputs, representations of aerosols, and El NiNo evolution, may explain most of the discrepancy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.P21G..01M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.P21G..01M"><span id="translatedtitle">Polar <span class="hlt">Warming</span> Drivers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>McDunn, T. L.; Bougher, S. W.; Mischna, M. A.; Murphy, J. R.</p> <p>2012-12-01</p> <p>Polar <span class="hlt">warming</span> is a dynamically induced temperature enhancement over mid-to-high latitudes that results in a reversed (poleward) meridional temperature gradient. This phenomenon was recently characterized over the 40-90 km altitude region [1] based on nearly three martian years of Mars Climate Sounder observations [2, 3]. Here we investigate which forcing mechanisms affect the magnitude and distribution of the observed polar <span class="hlt">warming</span> by conducting simulations with the Mars Weather Research and Forecasting General Circulation Model [4, 5]. We present simulations confirming the influence topography [6] and dust loading [e.g., 7] have upon polar <span class="hlt">warming</span>. We then present simulations illustrating the modulating influence gravity wave momentum deposition exerts upon polar <span class="hlt">warming</span>, consistent with previous modeling studies [e.g., 8]. The results of this investigation suggest the magnitude and distribution of polar <span class="hlt">warming</span> in the martian middle atmosphere is modified by gravity wave activity and that the characteristics of the gravity waves that most significantly affect polar <span class="hlt">warming</span> vary with season. References: [1] McDunn, et al., 2012 (JGR), [2]Kleinböhl, et al., 2009 (JGR), [3] Kleinböhl, et al., 2011 (JQSRT), [4] Richardson, et al., 2007 (JGR), [5] Mischna, et al., 2011 (Planet. Space Sci.), [6] Richardson and Wilson, 2002 (Nature), [7] Haberle, et al., 1982 (Icarus), [8] Barnes, 1990 (JGR).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70027100','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70027100"><span id="translatedtitle"><span class="hlt">Winter</span> ecology of spectacled eiders: Environmental characteristics and population change</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Petersen, M.R.; Douglas, D.C.</p> <p>2004-01-01</p> <p>We described characteristics of the <span class="hlt">wintering</span> area used by Spectacled Eiders (Somateria fischeri) in the Bering Sea, Alaska, and evaluated these characteristics in relation to long-term population trends. Remoteness, limited daylight, and <span class="hlt">extreme</span> weather conditions precluded direct observations, so we derived the location of the <span class="hlt">wintering</span> area from satellite telemetry, ice conditions from remotely sensed data, weather conditions from archived data sets, and benthic communities from the literature. Based on analyses of two indices spanning 1957-2002 and 1988-2002, we identified no single environmental parameter that explained the precipitous decline in nesting populations in western Alaska. In general, we found that the number of days with <span class="hlt">extreme</span> sea ice in <span class="hlt">winter</span>, <span class="hlt">extreme</span> winds, and winds in spring explained the greatest variability in annual indices. These analyses support the conclusion that annual population estimates on the breeding grounds can be negatively impacted by extended periods of dense sea-ice concentration and weather during the previous <span class="hlt">winter</span>. Examination of population indices did not support the hypothesis that changes in benthic community on the <span class="hlt">wintering</span> grounds have contributed to the decline or inhibited the recovery of the Spectacled Eider breeding population in western Alaska.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.cdc.gov/disasters/winter/beforestorm/supplylists.html','NIH-MEDLINEPLUS'); return false;" href="https://www.cdc.gov/disasters/winter/beforestorm/supplylists.html"><span id="translatedtitle"><span class="hlt">Winter</span> Weather Checklists</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... About CDC.gov . Natural Disasters and Severe Weather Earthquakes Being Prepared Emergency Supplies Home Hazards Indoor Safety ... Matters What's New Preparation & Planning Disasters & Severe Weather Earthquakes <span class="hlt">Extreme</span> Heat Floods Hurricanes Landslides Tornadoes Tsunamis Volcanoes ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.cdc.gov/disasters/winter/staysafe/frostbite.html','NIH-MEDLINEPLUS'); return false;" href="https://www.cdc.gov/disasters/winter/staysafe/frostbite.html"><span id="translatedtitle"><span class="hlt">Winter</span> Weather: Frostbite</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... About CDC.gov . Natural Disasters and Severe Weather Earthquakes Being Prepared Emergency Supplies Home Hazards Indoor Safety ... Matters What's New Preparation & Planning Disasters & Severe Weather Earthquakes <span class="hlt">Extreme</span> Heat Floods Hurricanes Landslides Tornadoes Tsunamis Volcanoes ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.cdc.gov/disasters/winter/duringstorm/outdoorsafety.html','NIH-MEDLINEPLUS'); return false;" href="https://www.cdc.gov/disasters/winter/duringstorm/outdoorsafety.html"><span id="translatedtitle"><span class="hlt">Winter</span> Weather: Outdoor Safety</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... About CDC.gov . Natural Disasters and Severe Weather Earthquakes Being Prepared Emergency Supplies Home Hazards Indoor Safety ... Matters What's New Preparation & Planning Disasters & Severe Weather Earthquakes <span class="hlt">Extreme</span> Heat Floods Hurricanes Landslides Tornadoes Tsunamis Volcanoes ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.cdc.gov/disasters/winter/duringstorm/indoorsafety.html','NIH-MEDLINEPLUS'); return false;" href="https://www.cdc.gov/disasters/winter/duringstorm/indoorsafety.html"><span id="translatedtitle"><span class="hlt">Winter</span> Weather: Indoor Safety</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... tips below. Take Action Be careful when using wood stoves, fireplaces, or space heaters to heat your ... Home Safely If you plan to use a wood stove, fireplace, or space heater, be <span class="hlt">extremely</span> careful. ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014GeoRL..41.3251B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014GeoRL..41.3251B"><span id="translatedtitle"><span class="hlt">Winter</span> fog is decreasing in the fruit growing region of the Central Valley of California</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Baldocchi, Dennis; Waller, Eric</p> <p>2014-05-01</p> <p>The Central Valley of California is home to a variety of fruit and nut trees. These trees account for 95% of the U.S. production, but they need a sufficient amount of <span class="hlt">winter</span> chill to achieve rest and quiescence for the next season's buds and flowers. In prior work, we reported that the accumulation of <span class="hlt">winter</span> chill is declining in the Central Valley. We hypothesize that a reduction in <span class="hlt">winter</span> fog is cooccurring and is contributing to the reduction in <span class="hlt">winter</span> chill. We examined a 33 year record of satellite remote sensing to develop a fog climatology for the Central Valley. We find that the number of <span class="hlt">winter</span> fog events, integrated spatially, decreased 46%, on average, over 32 <span class="hlt">winters</span>, with much year to year variability. Less fog means warmer air and an increase in the energy balance on buds, which amplifies their <span class="hlt">warming</span>, reducing their chill accumulation more.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..1710502O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..1710502O"><span id="translatedtitle">The recent <span class="hlt">warming</span> trend in North Greenland</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Orsi, Anais; Kawamura, Kenji; Masson-Delmotte, Valerie; Landais, Amaelle; Severinghaus, Jeff</p> <p>2015-04-01</p> <p>The arctic is the fastest <span class="hlt">warming</span> region on Earth, but it is also one where there is little historical data. Although summer <span class="hlt">warming</span> causes melt, the annual temperature trend is dominated by the <span class="hlt">winter</span> and fall season, which are much less well documented. In addition, the instrumental record relies principally on coastal weather stations, and there are very few direct temperature observations in the interior dating back more than 30 years, especially in North Greenland, where the current <span class="hlt">warming</span> trend is the largest. Here, we present a temperature reconstruction from NEEM (51°W, 77°N), in North Greenland, for the last 100 years, which allows us to put the recent trend in the context of the longer term climate. We use a combination of two independent proxies to reconstruct the temperature history at NEEM: borehole temperature and inert gas isotope measurements in the firn. Borehole temperature takes advantage of the low temperature diffusivity of the snow and ice, which allows the temperature history to be preserved in the ice for several centuries. Temperature gradients in the firn (old snow above the ice) influence the gas isotopic composition: thermal fractionation causes heavy isotopes to concentrate on the cold end of the firn column. We measured the isotopes of inert gases (N2, Ar and Kr), which have a constant atmospheric composition through time, and use the thermal fractionation signal as an additional constraint on the temperature history at the site. We find that NEEM has been <span class="hlt">warming</span> by 0.86±0.22°C/decade over the past 30 years, from -28.55±0.29°C for the 1900-1970 average to -26.77±0.16°C for the 2000-2010 average. The <span class="hlt">warming</span> rate at NEEM is similar to that of Greenland Summit, and confirms the large <span class="hlt">warming</span> trends in North Greenland (polar amplification) and high altitude sites (tropospheric rather than surface <span class="hlt">warming</span>). Water isotopes show that the recent past has not met the level of the 1928 anomaly; but the average of the past 30 years has</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2889344','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2889344"><span id="translatedtitle">Decreased <span class="hlt">winter</span> severity increases viability of a montane frog population</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>McCaffery, Rebecca M.; Maxell, Bryce A.</p> <p>2010-01-01</p> <p>Many proximate causes of global amphibian declines have been well documented, but the role that climate change has played and will play in this crisis remains ambiguous for many species. Breeding phenology and disease outbreaks have been associated with <span class="hlt">warming</span> temperatures, but, to date, few studies have evaluated effects of climate change on individual vital rates and subsequent population dynamics of amphibians. We evaluated relationships among local climate variables, annual survival and fecundity, and population growth rates from a 9-year demographic study of Columbia spotted frogs (Rana luteiventris) in the Bitterroot Mountains of Montana. We documented an increase in survival and breeding probability as severity of <span class="hlt">winter</span> decreased. Therefore, a <span class="hlt">warming</span> climate with less severe <span class="hlt">winters</span> is likely to promote population viability in this montane frog population. More generally, amphibians and other ectotherms inhabiting alpine or boreal habitats at or near their thermal ecological limits may benefit from the milder <span class="hlt">winters</span> provided by a <span class="hlt">warming</span> climate as long as suitable habitats remain intact. A more thorough understanding of how climate change is expected to benefit or harm amphibian populations at different latitudes and elevations is essential for determining the best strategies to conserve viable populations and allow for gene flow and shifts in geographic range. PMID:20421473</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15891822','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15891822"><span id="translatedtitle">Will loss of snow cover during climatic <span class="hlt">warming</span> expose New Zealand alpine plants to increased frost damage?</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bannister, Peter; Maegli, Tanja; Dickinson, Katharine J M; Halloy, Stephan R P; Knight, Allison; Lord, Janice M; Mark, Alan F; Spencer, Katrina L</p> <p>2005-06-01</p> <p>If snow cover in alpine environments were reduced through climatic <span class="hlt">warming</span>, plants that are normally protected by snow-lie in <span class="hlt">winter</span> would become exposed to greater <span class="hlt">extremes</span> of temperature and solar radiation. We examined the annual course of frost resistance of species of native alpine plants from southern New Zealand that are normally buried in snowbanks over <span class="hlt">winter</span> (Celmisia haastii and Celmisia prorepens) or in sheltered areas that may accumulate snow (Hebe odora) and other species, typical of more exposed areas, that are relatively snow-free (Celmisia viscosa, Poa colensoi, Dracophyllum muscoides). The frost resistance of these principal species was in accord with habitat: those from snowbanks or sheltered areas showed the least frost resistance, whereas species from exposed areas had greater frost resistance throughout the year. P. colensoi had the greatest frost resistance (-32.5 degrees C). All the principal species showed a rapid increase in frost resistance from summer to early <span class="hlt">winter</span> (February-June) and maximum frost resistance in <span class="hlt">winter</span> (July-August). The loss of resistance in late <span class="hlt">winter</span> to early summer (August-December) was most rapid in P. colensoi and D. muscoides. Seasonal frost resistance of the principal species was more strongly related to daylength than to temperature, although all species except C. viscosa were significantly related to temperature when the influence of daylength was accounted for. Measurements of chlorophyll fluorescence indicated that photosynthetic efficiency of the principal species declined with increasing daylength. Levels of frost resistance of the six principal alpine plant species, and others measured during the growing season, were similar to those measured in tropical alpine areas and somewhat more resistant than those recorded in alpine areas of Europe. The potential for frost damage was greatest in spring. The current relationship of frost resistance with daylength is sufficient to prevent damage at any time of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25322929','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25322929"><span id="translatedtitle">Climate change in our backyards: the reshuffling of North America's <span class="hlt">winter</span> bird communities.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Princé, Karine; Zuckerberg, Benjamin</p> <p>2015-02-01</p> <p>Much of the recent changes in North American climate have occurred during the <span class="hlt">winter</span> months, and as result, overwintering birds represent important sentinels of anthropogenic climate change. While there is mounting evidence that bird populations are responding to a <span class="hlt">warming</span> climate (e.g., poleward shifts) questions remain as to whether these species-specific responses are resulting in community-wide changes. Here, we test the hypothesis that a changing <span class="hlt">winter</span> climate should favor the formation of <span class="hlt">winter</span> bird communities dominated by <span class="hlt">warm</span>-adapted species. To do this, we quantified changes in community composition using a functional index--the Community Temperature Index (CTI)--which measures the balance between low- and high-temperature dwelling species in a community. Using data from Project FeederWatch, an international citizen science program, we quantified spatiotemporal changes in <span class="hlt">winter</span> bird communities (n = 38 bird species) across eastern North America and tested the influence of changes in <span class="hlt">winter</span> minimum temperature over a 22-year period. We implemented a jackknife analysis to identify those species most influential in driving changes at the community level and the population dynamics (e.g., extinction or colonization) responsible for these community changes. Since 1990, we found that the <span class="hlt">winter</span> bird community structure has changed with communities increasingly composed of <span class="hlt">warm</span>-adapted species. This reshuffling of <span class="hlt">winter</span> bird communities was strongest in southerly latitudes and driven primarily by local increases in abundance and regional patterns of colonization by southerly birds. CTI tracked patterns of changing <span class="hlt">winter</span> temperature at different temporal scales ranging from 1 to 35 years. We conclude that a shifting <span class="hlt">winter</span> climate has provided an opportunity for smaller, southerly distributed species to colonize new regions and promote the formation of unique <span class="hlt">winter</span> bird assemblages throughout eastern North America.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6914531','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6914531"><span id="translatedtitle">Global <span class="hlt">warming</span> on trial</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Broeker, W.S.</p> <p>1992-04-01</p> <p>Jim Hansen, a climatologist at NASA's Goddard Space Institute, is convinced that the earth's temperature is rising and places the blame on the buildup of greenhouse gases in the atmosphere. Unconvinced, John Sununu, former White House chief of staff, doubts that the <span class="hlt">warming</span> will be great enough to produce serious threat and fears that measures to reduce the emissions would throw a wrench into the gears that drive the Unites States' troubled economy. During his three years at the White House, Sununu's view prevailed, and although his role in the debate has diminished, others continue to cast doubt on the reality of global <span class="hlt">warming</span>. A new lobbying group called the Climate Council has been created to do just this. Burning fossil fuels is not the only problem; a fifth of emissions of carbon dioxide now come from clearing and burning forests. Scientists are also tracking a host of other greenhouse gases that emanate from a variety of human activities; the <span class="hlt">warming</span> effect of methane, chlorofluorocarbons and nitrous oxide combined equals that of carbon dioxide. Although the current <span class="hlt">warming</span> from these gases may be difficult to detect against the background noise of natural climate variation, most climatologists are certain that as the gases continue to accumulate, increases in the earth's temperature will become evident even to skeptics. If the reality of global <span class="hlt">warming</span> were put on trial, each side would have trouble making its case. Jim Hansen's side could not prove beyond a reasonable doubt that carbon dioxide and other greenhouse gases have <span class="hlt">warmed</span> the planet. But neither could John Sununu's side prove beyond a reasonable doubt that the <span class="hlt">warming</span> expected from greenhouse gases has not occurred. To see why each side would have difficulty proving its case, this article reviews the arguments that might be presented in such a hearing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/234035','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/234035"><span id="translatedtitle">Implication of climate <span class="hlt">warming</span> for agricultural production in eastern China</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wang Futang</p> <p>1996-03-01</p> <p>According to the regional climate change scenarios for China estimated by the composite GCM, the potential impacts of climate <span class="hlt">warming</span> on rice, <span class="hlt">winter</span> wheat and corn production in eastern agricultural areas and cropping systems in China in future are simulated in this paper, using the weather-yield model and cropping system model. As a result, it is shown that under the current planting systems and agrotechniques the climate <span class="hlt">warming</span> effect upon the corn production is the most significant, impact upon the <span class="hlt">winter</span> wheat is the next one and the smallest one is that upon the rice. The regional and seasonal features of impacts on various crops are rather different. And also, there will be a substantial northward shift of the cropping patterns, such as the northern boundary of triple cropping area would shift from its current border at Yangtze River toward Yellow River. However, it is still difficult to draw a specific conclusion that climate <span class="hlt">warming</span> will be advantageous or disadvantageous for farm in China, because of significant negative balance between precipitation and evapotranspiration increase and a lot of scientific uncertainties in the investigation of climate <span class="hlt">warming</span>, GCM prediction and complex-various impact of climate <span class="hlt">warming</span> on agricultural production.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/470966','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/470966"><span id="translatedtitle">Geographical features of global water cycle during <span class="hlt">warm</span> geological epochs</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Georgiadi, A.G.</p> <p>1996-12-31</p> <p>The impact of global <span class="hlt">warming</span> on the water cycle can be <span class="hlt">extremely</span> complex and diverse. The goal of the investigation was to estimate the geographic features of the mean annual water budget of the world during climatic optimums of the Holocene and the Eemian interglacial periods. These geological epochs could be used as analogs of climatic <span class="hlt">warming</span> on 1 degree, centigrade and 2 degrees, centigrade. The author used the results of climatic reconstructions based on a simplified version of a GCM.</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/2014EGUGA..1611254Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..1611254Z"><span id="translatedtitle">Interannual variability of <span class="hlt">Winter</span> Precipitation in Southeast China</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Ling; Fraedrich, Klaus; zhu, Xiuhua; Sielmann, Frank</p> <p>2014-05-01</p> <p>The observed <span class="hlt">winter</span> (DJF) precipitation in Southeast China (1961-2010) is characterized by a monopole pattern of the three-monthly Standardized Precipitation Index (SPI-3) whose interannual variability is related to the anomalies of East Asian <span class="hlt">Winter</span> Monsoon (EAWM) systems. Dynamic composites and linear regression analysis indicate that the intensity of EAWM and Siberia High (SH), the position of East Asian Trough (EAT), El Niño events and SST anomalies over South China Sea (SCS) influence different regions of anomalous Southeast China <span class="hlt">winter</span> precipitation on interannual scales. The circulation indices (EAWM, SH and EAT) mainly affect the <span class="hlt">winter</span> precipitation in the eastern part of Southeast China. El Niño events affect the South China <span class="hlt">winter</span> precipitation due to the anticyclone anomalies over Philippines. The effect of SCS SST anomalies on the <span class="hlt">winter</span> precipitation is mainly in the south part of Yangtze River. And the contributions from all the impact factors do not counteract with one another to generate the Southeast China <span class="hlt">winter</span> precipitation variability. Thus, a set of circulation regimes, represented by a handful indices, provide the basis for modeling precipitation anomalies or <span class="hlt">extremes</span> in future climate projections.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMGC41D0599L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMGC41D0599L"><span id="translatedtitle">Changes in Terrestrial Water Availability under Global <span class="hlt">Warming</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lan, C. W.; Lo, M. H.; Chou, C.</p> <p>2014-12-01</p> <p>Under global <span class="hlt">warming</span>, the annual range of precipitation is widening (Chou and Lan, 2012; Chou et al., 2013) and the frequency of precipitation <span class="hlt">extreme</span> events also increases. Due to nonlinear responses of land hydrological process to precipitation <span class="hlt">extremes</span>, runoff can increase exponentially, and on the hard hand, soil water storage may decline. In addition, IPCC AR5 indicates that soil moisture decreases in most areas under the global <span class="hlt">warming</span> scenario. In this study, we use NCAR Community Land Model version 4 (CLM4) to simulate changes in terrestrial available water (TAW, defined as the precipitation minus evaporation minus runoff, and then divided by the precipitation) under global <span class="hlt">warming</span>. Preliminary results show that the TAW has clear seasonal variations. Compared to previous studies, which do not include the runoff in the calculations of the available water, our estimates on the TAW has much less available water in high latitudes through out the year, especially under <span class="hlt">extreme</span> precipitation events.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ClDy..tmp..265W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ClDy..tmp..265W"><span id="translatedtitle">Tropospheric circulation during the early twentieth century Arctic <span class="hlt">warming</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wegmann, Martin; Brönnimann, Stefan; Compo, Gilbert P.</p> <p>2016-06-01</p> <p>The early twentieth century Arctic <span class="hlt">warming</span> (ETCAW) between 1920 and 1940 is an exceptional feature of climate variability in the last century. Its <span class="hlt">warming</span> rate was only recently matched by recent <span class="hlt">warming</span> in the region. Unlike recent <span class="hlt">warming</span> largely attributable to anthropogenic radiative forcing, atmospheric <span class="hlt">warming</span> during the ETCAW was strongest in the mid-troposphere and is believed to be triggered by an exceptional case of natural climate variability. Nevertheless, ultimate mechanisms and causes for the ETCAW are still under discussion. Here we use state of the art multi-member global circulation models, reanalysis and reconstruction datasets to investigate the internal atmospheric dynamics of the ETCAW. We investigate the role of boreal <span class="hlt">winter</span> mid-tropospheric heat transport and circulation in providing the energy for the large scale <span class="hlt">warming</span>. Analyzing sensible heat flux components and regional differences, climate models are not able to reproduce the heat flux evolution found in reanalysis and reconstruction datasets. These datasets show an increase of stationary eddy heat flux and a decrease of transient eddy heat flux during the ETCAW. Moreover, tropospheric circulation analysis reveals the important role of both the Atlantic and the Pacific sectors in the convergence of southerly air masses into the Arctic during the <span class="hlt">warming</span> event. Subsequently, it is suggested that the internal dynamics of the atmosphere played a major role in the formation in the ETCAW.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=PIA07338&hterms=fog&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dfog','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=PIA07338&hterms=fog&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dfog"><span id="translatedtitle"><span class="hlt">Winter</span> Frost and Fog</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2005-01-01</p> <p><p/> This somewhat oblique blue wide angle Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows the 174 km (108 mi) diameter crater, Terby, and its vicinity in December 2004. Located north of Hellas, this region can be covered with seasonal frost and ground-hugging fog, even in the afternoon, despite being north of 30oS. The subtle, wavy pattern is a manifestation of fog. <p/> <i>Location near</i>: 28oS, 286oW <i>Illumination from</i>: upper left <i>Season</i>: Southern <span class="hlt">Winter</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..14.5816M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..14.5816M"><span id="translatedtitle">Shifts during the snow season in the Romanian Carpathians in response to <span class="hlt">winter</span> temperature and precipitation change</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Micu, D.</p> <p>2012-04-01</p> <p>Snowpack characteristics and duration are considered to be key indicators of climate change in mountain regions, particularly during the <span class="hlt">winter</span> season when its environmental and economic importance is notable. The present study is focused on relevant snow statistics over a 43-year period of meteorological observations at several climatological stations (15) located above 1,000 m a.s.l. in the Romanian Carpathians. Here the snow season is considered to last from the 1st of November to the 30th of April when snowpack reaches the highest stability and thickness in most of the studied locations. <span class="hlt">Winter</span> temperature and precipitation change signals are investigated as main triggering factors of snow season changes (i.e. snow vs. rain, seasonal snowfall onset and offset, snowpack duration s.o.). The current mountain climate <span class="hlt">warming</span> is obvious, determining a generalized decreasing trend of the snow-to-rain ratio. The alpine areas are also experiencing temperature increases and a higher frequency of positive <span class="hlt">extremes</span> (e.g. <span class="hlt">winter</span> heat waves). Earlier spring snowmelt was also statistically proved both at regional level and by elevation levels. <span class="hlt">Winter</span> precipitation varies from year to year and over decades, and changes in amount, intensity, frequency, and type (e.g. snow vs rain) affect both the environment and society. Periods in which snow was abundant or not were also investigated in relation to the large-scale forcing (e.g. the <span class="hlt">winter</span> North Atlantic Oscillation index fluctuations as a measure of strength of the westerly flow from the Atlantic and of cyclonic activity trends). The shifts observed in the Romanian Carpathians snow season are comparable to <span class="hlt">winter</span> climate change estimated from observational data recorded also in other European mountain regions (e.g. the Swiss Alps, the French Alps and the Tatra Mts.). The results indicate that since mid-1980s the Romanian Carpathians have shown an obvious trend towards late Fall snowfall and snowpack onset (more evident below</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ThApC.tmp..337C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ThApC.tmp..337C"><span id="translatedtitle">Recent <span class="hlt">warming</span> trend in the coastal region of Qatar</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cheng, Way Lee; Saleem, Ayman; Sadr, Reza</p> <p>2015-12-01</p> <p>The objective of this study was to analyze long-term temperature-related phenomena in the eastern portion of the Middle East, focusing on the coastal region of Qatar. <span class="hlt">Extreme</span> temperature indices were examined, which were defined by the Expert Team on Climate Change Detection and Indices, for Doha, Qatar; these indices were then compared with those from neighboring countries. The trends were calculated for a 30-year period (1983-2012), using hourly data obtained from the National Climatic Data Center. The results showed spatially consistent <span class="hlt">warming</span> trends throughout the region. For Doha, 11 of the 12 indices studied showed significant <span class="hlt">warming</span> trends. In particular, the <span class="hlt">warming</span> trends were represented by an increase in the number of <span class="hlt">warm</span> days and nights and a decrease in the number of cool nights and days. The high-temperature <span class="hlt">extremes</span> during the night have risen at more than twice the rate of their corresponding daytime <span class="hlt">extremes</span>. The intensity and frequency of hot days have increased, and the minimum temperature indices exhibited a higher rate of <span class="hlt">warming</span>. The climatic changes in Doha are consistent with the region-wide heat-up in recent decades across the Middle East. However, the rapid economic expansion, increase of population since the 1990s, and urban effects in the region are thought to have intensified the rapidly <span class="hlt">warming</span> climate pattern observed in Doha since the turn of the century.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013GeoRL..40..579S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013GeoRL..40..579S"><span id="translatedtitle">Six month-lead downscaling prediction of <span class="hlt">winter</span> to spring drought in South Korea based on a multimodel ensemble</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sohn, Soo-Jin; Ahn, Joong-Bae; Tam, Chi-Yung</p> <p>2013-02-01</p> <p><title type="main">Abstract The potential of using a dynamical-statistical method for long-lead drought prediction was investigated. In particular, the APEC Climate Center one-tier multimodel ensemble (MME) was downscaled for predicting the standardized precipitation evapotranspiration index (SPEI) over 60 stations in South Korea. SPEI depends on both precipitation and temperature, and can incorporate the effect of global <span class="hlt">warming</span> on the balance between precipitation and evapotranspiration. It was found that the one-tier MME has difficulty in capturing the local temperature and rainfall variations over extratropical land areas, and has no skill in predicting SPEI during boreal <span class="hlt">winter</span> and spring. On the other hand, temperature and precipitation predictions were substantially improved in the downscaled MME. In conjunction with variance inflation, downscaled MME can give reasonably skillful 6 month-lead forecasts of SPEI for the <span class="hlt">winter</span> to spring period. Our results could lead to more reliable hydrological <span class="hlt">extreme</span> predictions for policymakers and stakeholders in the water management sector, and for better mitigation and climate adaptations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=PIA09088&hterms=spirit&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dspirit','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=PIA09088&hterms=spirit&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dspirit"><span id="translatedtitle">Spirit's <span class="hlt">Winter</span> Work Site</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2006-01-01</p> <p><p/> [figure removed for brevity, see original site] Annotated Version <p/> This portion of an image acquired by the Mars Reconnaissance Orbiter's High Resolution Imaging Science Experiment camera shows the Spirit rover's <span class="hlt">winter</span> campaign site. Spirit was parked on a slope tilted 11 degrees to the north to maximize sunlight during the southern <span class="hlt">winter</span> season. 'Tyrone' is an area where the rover's wheels disturbed light-toned soils. Remote sensing and in-situ analyses found the light-toned soil at Tyrone to be sulfate rich and hydrated. The original picture is catalogued as PSP_001513_1655_red and was taken on Sept. 29, 2006. <p/> NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, is the prime contractor for the project and built the spacecraft. The High Resolution Imaging Science Experiment is operated by the University of Arizona, Tucson, and the instrument was built by Ball Aerospace and Technology Corp., Boulder, Colo.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22695877','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22695877"><span id="translatedtitle">Global <span class="hlt">warming</span> and allergy in Asia Minor.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bajin, Munir Demir; Cingi, Cemal; Oghan, Fatih; Gurbuz, Melek Kezban</p> <p>2013-01-01</p> <p>The earth is <span class="hlt">warming</span>, and it is <span class="hlt">warming</span> quickly. Epidemiological studies have demonstrated that global <span class="hlt">warming</span> is correlated with the frequency of pollen-induced respiratory allergy and allergic diseases. There is a body of evidence suggesting that the prevalence of allergic diseases induced by pollens is increasing in developed countries, a trend that is also evident in the Mediterranean area. Because of its mild <span class="hlt">winters</span> and sunny days with dry summers, the Mediterranean area is different from the areas of central and northern Europe. Classical examples of allergenic pollen-producing plants of the Mediterranean climate include Parietaria, Olea and Cupressaceae. Asia Minor is a Mediterranean region that connects Asia and Europe, and it includes considerable coastal areas. Gramineae pollens are the major cause of seasonal allergic rhinitis in Asia Minor, affecting 1.3-6.4 % of the population, in accordance with other European regions. This article emphasizes the importance of global climate change and anticipated increases in the prevalence and severity of allergic disease in Asia Minor, mediated through worsening air pollution and altered local and regional pollen production, from an otolaryngologic perspective.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27145612','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27145612"><span id="translatedtitle">Beyond arctic and alpine: the influence of <span class="hlt">winter</span> climate on temperate ecosystems.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ladwig, Laura M; Ratajczak, Zak R; Ocheltree, Troy W; Hafich, Katya A; Churchill, Amber C; Frey, Sarah J K; Fuss, Colin B; Kazanski, Clare E; Muñoz, Juan D; Petrie, Matthew D; Reinmann, Andrew B; Smith, Jane G</p> <p>2016-02-01</p> <p><span class="hlt">Winter</span> climate is expected to change under future climate scenarios, yet the majority of <span class="hlt">winter</span> ecology research is focused in cold-climate ecosystems. In many temperate systems, it is unclear how <span class="hlt">winter</span> climate relates to biotic responses during the growing season. The objective of this study was to examine how <span class="hlt">winter</span> weather relates to plant and animal communities in a variety of terrestrial ecosystems ranging from <span class="hlt">warm</span> deserts to alpine tundra. Specifically, we examined the association between <span class="hlt">winter</span> weather and plant phenology, plant species richness, consumer abundance, and consumer richness in 11 terrestrial ecosystems associated with the U.S. Long-Term Ecological Research (LTER) Network. To varying degrees, <span class="hlt">winter</span> precipitation and temperature were correlated with all biotic response variables. Bud break was tightly aligned with end of <span class="hlt">winter</span> temperatures. For half the sites, <span class="hlt">winter</span> weather was a better predictor of plant species richness than growing season weather. Warmer <span class="hlt">winters</span> were correlated with lower consumer abundances in both temperate and alpine systems. Our findings suggest <span class="hlt">winter</span> weather may have a strong influence on biotic activity during the growing season and should be considered in future studies investigating the effects of climate change on both alpine and temperate systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/12916893','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/12916893"><span id="translatedtitle"><span class="hlt">Winter</span> sports injuries. The 2002 <span class="hlt">Winter</span> Olympics experience and a review of the literature.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Crim, Julia R</p> <p>2003-05-01</p> <p>Injury patterns at the 2002 <span class="hlt">Winter</span> Olympics were similar to those in recreational <span class="hlt">winter</span> athletes, although injury rates were higher. The high rates of injury compared with reported rates in recreational athletes reflect the intensity of the competition and the high speeds of the athletes. In addition, rates are artificially elevated because we were not able to count the number of practice runs by each athlete, only the number of races. The highest rates of injuries resulting in positive MR imaging or plain radiographs were in snowboarders (28/1000 races), followed by alpine skiers (20/1000). In all of the <span class="hlt">winter</span> sports, the most commonly injured joint was the knee (37 injuries), and the most common knee injury was the ACL tear. Injuries to the foot and ankle were second in frequency (15 injuries). It is interesting that three of the ankle injuries were syndesmosis sprains; this may be an underreported injury in <span class="hlt">winter</span> sports. There were 12 injuries to the upper <span class="hlt">extremity</span>, all but two to the shoulder. Back complaints were frequent, but only seven patients had significant imaging abnormalities found in the lumbar spine: two stress fractures of the pedicles, one acute pedicle fracture, one spondylolysis, and four disc protrusions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4690898','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4690898"><span id="translatedtitle">Role of Acclimatization in Weather-Related Human Mortality During the Transition Seasons of Autumn and Spring in a Thermally <span class="hlt">Extreme</span> Mid-Latitude Continental Climate</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>de Freitas, Christopher R.; Grigorieva, Elena A.</p> <p>2015-01-01</p> <p>Human mortality is closely related to natural climate-determined levels of thermal environmental stress and the resulting thermophysiological strain. Most climate-mortality research has focused on seasonal <span class="hlt">extremes</span> during <span class="hlt">winter</span> and summer when mortality is the highest, while relatively little attention has been paid to mortality during the transitional seasons of autumn and spring. The body acclimatizes to heat in the summer and cold in <span class="hlt">winter</span> and readjusts through acclimatization during the transitions between the two during which time the body experiences the thermophysiological strain of readjustment. To better understand the influences of weather on mortality through the acclimatization process, the aim here is to examine the periods that link very cold and very <span class="hlt">warms</span> seasons. The study uses the Acclimatization Thermal Strain Index (ATSI), which is a comparative measure of short-term thermophysiological impact on the body. ATSI centers on heat exchange with the body’s core via the respiratory system, which cannot be protected. The analysis is based on data for a major city in the climatic region of the Russian Far East characterized by very hot summers and <span class="hlt">extremely</span> cold <span class="hlt">winters</span>. The results show that although mortality peaks in <span class="hlt">winter</span> (January) and is at its lowest in summer (August), there is not a smooth rise through autumn nor a smooth decline through spring. A secondary peak occurs in autumn (October) with a smaller jump in May. This suggests the acclimatization from <span class="hlt">warm</span>-to-cold produces more thermophysiological strain than the transition from cold-to-<span class="hlt">warm</span>. The study shows that ATSI is a useful metric for quantifying the extent to which biophysical adaptation plays a role in increased strain on the body during re-acclimatization and for this reason is a more appropriate climatic indictor than air temperature alone. The work gives useful bioclimatic information on risks involved in transitional seasons in regions characterized by climatic <span class="hlt">extremes</span>. This</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26703633','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26703633"><span id="translatedtitle">Role of Acclimatization in Weather-Related Human Mortality During the Transition Seasons of Autumn and Spring in a Thermally <span class="hlt">Extreme</span> Mid-Latitude Continental Climate.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>de Freitas, Christopher R; Grigorieva, Elena A</p> <p>2015-11-26</p> <p>Human mortality is closely related to natural climate-determined levels of thermal environmental stress and the resulting thermophysiological strain. Most climate-mortality research has focused on seasonal <span class="hlt">extremes</span> during <span class="hlt">winter</span> and summer when mortality is the highest, while relatively little attention has been paid to mortality during the transitional seasons of autumn and spring. The body acclimatizes to heat in the summer and cold in <span class="hlt">winter</span> and readjusts through acclimatization during the transitions between the two during which time the body experiences the thermophysiological strain of readjustment. To better understand the influences of weather on mortality through the acclimatization process, the aim here is to examine the periods that link very cold and very <span class="hlt">warms</span> seasons. The study uses the Acclimatization Thermal Strain Index (ATSI), which is a comparative measure of short-term thermophysiological impact on the body. ATSI centers on heat exchange with the body’s core via the respiratory system, which cannot be protected. The analysis is based on data for a major city in the climatic region of the Russian Far East characterized by very hot summers and <span class="hlt">extremely</span> cold <span class="hlt">winters</span>. The results show that although mortality peaks in <span class="hlt">winter</span> (January) and is at its lowest in summer (August), there is not a smooth rise through autumn nor a smooth decline through spring. A secondary peak occurs in autumn (October) with a smaller jump in May. This suggests the acclimatization from <span class="hlt">warm</span>-to-cold produces more thermophysiological strain than the transition from cold-to-<span class="hlt">warm</span>. The study shows that ATSI is a useful metric for quantifying the extent to which biophysical adaptation plays a role in increased strain on the body during re-acclimatization and for this reason is a more appropriate climatic indictor than air temperature alone. The work gives useful bioclimatic information on risks involved in transitional seasons in regions characterized by climatic <span class="hlt">extremes</span>. This</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRD..122.1524H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRD..122.1524H"><span id="translatedtitle">Potential vorticity regimes over East Asia during <span class="hlt">winter</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Huang, Wenyu; Chen, Ruyan; Wang, Bin; Wright, Jonathon S.; Yang, Zifan; Ma, Wenqian</p> <p>2017-02-01</p> <p>Nine potential vorticity (PV) regimes over East Asia are identified by applying a Self-Organizing Map and Hierarchical Ascendant Classification regime analysis to the daily PV reanalysis fields on the 300 K isentropic surface for December-March 1948-2014. According to the surface temperature anomalies over East Asia, these nine regimes are further classified into three classes, i.e., cold class (three regimes), <span class="hlt">warm</span> class (four regimes), and neutral class (two regimes). The PV-based East Asian <span class="hlt">winter</span> monsoon index (EAWMI) is used to study the relationship between PV distributions and the temperature anomalies. The magnitude of cold (<span class="hlt">warm</span>) anomalies over the land areas of East Asia increases (decreases) quasi-linearly with the EAWMI. Regression analysis reveals that cold temperature anomalies preferentially occur when the EAWMI exceeds a threshold at ˜0.2 PVU (where 1 PVU ≡ 10-6 m2 K kg-1 s-1). PV inversion uncovers the mechanisms behind the relationships between the PV regimes and surface temperature anomalies and reveals that cold (<span class="hlt">warm</span>) PV regimes are associated with significant <span class="hlt">warming</span> (cooling) in the upper troposphere and lower stratosphere. On average, cold regimes have longer durations than <span class="hlt">warm</span> regimes. Interclass transition probabilities are much higher for paths from <span class="hlt">warm</span>/neutral regimes to cold regimes than for paths from cold regimes to <span class="hlt">warm</span>/neutral regimes. Besides, intraclass transitions are rare within the <span class="hlt">warm</span> or neutral regimes. The PV regime analysis provides insight into the causes of severe cold spells over East Asia, with blocking circulation patterns identified as the primary factor in initiating and maintaining these cold spells.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1992Natur.357..320S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1992Natur.357..320S"><span id="translatedtitle">Possible methane-induced polar <span class="hlt">warming</span> in the early Eocene</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sloan, L. C.; Walker, James C. G.; Moore, T. C., Jr.; Rea, David K.; Zachos, James C.</p> <p>1992-05-01</p> <p>Estimates of Eocene wetland areas are considered and it is suggested that the flux of methane may have been substantially greater during the Eocene than at present. Elevated methane concentrations would have enhanced early Eocene global <span class="hlt">warming</span> and also might have prevented severe <span class="hlt">winter</span> cooling of polar regions because of the potential of atmospheric methane to promote the formation of optically thick polar stratospheric ice clouds.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.6554D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.6554D"><span id="translatedtitle">Changes in annual temperature and precipitation <span class="hlt">extremes</span> in the Carpathians since AD 1961</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dumitrescu, Alexandru; Birsan, Marius-Victor; Magdalena Micu, Dana; Cheval, Sorin</p> <p>2014-05-01</p> <p> high and low elevation areas. The positive shift in the upper tail of summer maximum temperature distribution largely explains the intensification of this signal after mid 1980s or early 1990s, over extended areas within the Carpathian region. The changes in the occurrence of tropical nights are substantial only in low elevation areas (below 700 m) located outside the Carpathian Mountains, which are particularly exposed to persistent and intense <span class="hlt">warm</span> spells in summer. The <span class="hlt">Warm</span> Spell Duration Index is increasing over 60% of the area, showing a coherent pattern related rather to geographical position than to elevation. The shifts in the lower end of minimum temperature distribution suggest a lower frequency of <span class="hlt">extreme</span> cold conditions, favouring an extended increase in the probability of warmer <span class="hlt">winter</span> temperatures. The areas experiencing significant decreases of cold spell duration are rather scattered across the region. The trend patterns are consistent over the region (there are no mixed trends for a given index). Regional differences in climate <span class="hlt">extreme</span> trends within the Carpathian region are related to altitude, rather than latitude. The (annual) East Atlantic pattern shows strong correlations with the <span class="hlt">warm</span>-related indices. Our results are in agreement with previous studies on precipitation and temperature <span class="hlt">extremes</span> in the region. This study has been done within the project CC-WARE (SEE/D/0143/2.1/X).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25712272','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25712272"><span id="translatedtitle">Ice cover extent drives phytoplankton and bacterial community structure in a large north-temperate lake: implications for a <span class="hlt">warming</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>Beall, B F N; Twiss, M R; Smith, D E; Oyserman, B O; Rozmarynowycz, M J; Binding, C E; Bourbonniere, R A; Bullerjahn, G S; Palmer, M E; Reavie, E D; Waters, Lcdr M K; Woityra, Lcdr W C; McKay, R M L</p> <p>2016-06-01</p> <p>Mid-<span class="hlt">winter</span> limnological surveys of Lake Erie captured <span class="hlt">extremes</span> in ice extent ranging from expansive ice cover in 2010 and 2011 to nearly ice-free waters in 2012. Consistent with a <span class="hlt">warming</span> climate, ice cover on the Great Lakes is in decline, thus the ice-free condition encountered may foreshadow the lakes future <span class="hlt">winter</span> state. Here, we show that pronounced changes in annual ice cover are accompanied by equally important shifts in phytoplankton and bacterial community structure. Expansive ice cover supported phytoplankton blooms of filamentous diatoms. By comparison, ice free conditions promoted the growth of smaller sized cells that attained lower total biomass. We propose that isothermal mixing and elevated turbidity in the absence of ice cover resulted in light limitation of the phytoplankton during <span class="hlt">winter</span>. Additional insights into microbial community dynamics were gleaned from short 16S rRNA tag (Itag) Illumina sequencing. UniFrac analysis of Itag sequences showed clear separation of microbial communities related to presence or absence of ice cover. Whereas the ecological implications of the changing bacterial community are unclear at this time, it is likely that the observed shift from a phytoplankton community dominated by filamentous diatoms to smaller cells will have far reaching ecosystem effects including food web disruptions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA574657','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA574657"><span id="translatedtitle">Simulation of <span class="hlt">Extreme</span> Arctic Cyclones in IPCC AR5 Experiments</span></a></p> <p><a target="_blank" href="https://publicaccess.dtic.mil/psm/api/service/search/search">DTIC Science & Technology</a></p> <p></p> <p>2012-09-30</p> <p>of the current generation of global climate models (GCMs) to simulate <span class="hlt">extreme</span> Arctic cyclones and identify changes in the characteristics of these...2011). 5. The CCSM4 simulations show an interesting shift in the location of <span class="hlt">extreme</span> Arctic cyclones as a function of greenhouse <span class="hlt">warming</span> (Figure 1...preferred track over the North Atlantic-Barents Sea. However, this change is not effected by the modest greenhouse <span class="hlt">warming</span> between 1850-2000, when</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=cool&pg=3&id=EJ1002704','ERIC'); return false;" href="http://eric.ed.gov/?q=cool&pg=3&id=EJ1002704"><span id="translatedtitle"><span class="hlt">Warm</span> and Cool Cityscapes</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Jubelirer, Shelly</p> <p>2012-01-01</p> <p>Painting cityscapes is a great way to teach first-grade students about <span class="hlt">warm</span> and cool colors. Before the painting begins, the author and her class have an in-depth discussion about big cities and what types of buildings or structures that might be seen in them. They talk about large apartment and condo buildings, skyscrapers, art museums,…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED263758.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED263758.pdf"><span id="translatedtitle"><span class="hlt">Warming</span> Up to Communication.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Garner, Lucia Caycedo; Rusch, Debbie</p> <p></p> <p>Daily <span class="hlt">warm</span>-up exercises are advocated as a means of bridging the gap between previously unrelated activities outside the classroom and immersion into the second language, relaxing the class, and establishing a mood for communication. Variety, careful preparation, assuring that the students understand the activity, feeling free to discontinue an…</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('http://adsabs.harvard.edu/abs/2011NatCC...1..437.','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011NatCC...1..437."><span id="translatedtitle">Global <span class="hlt">warming</span> 'confirmed'</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p></p> <p>2011-12-01</p> <p>In October, the Berkeley Earth Surface Temperature project, funded in part by climate sceptics, concluded that the Earth is <span class="hlt">warming</span> based on the most comprehensive review of the data yet. Nature Climate Change talks to the project's director, physicist Richard Muller.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1817150I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1817150I"><span id="translatedtitle">Seasonal Forecasts for Northern Hemisphere <span class="hlt">Winter</span> 2015/16</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ineson, Sarah; Scaife, Adam; Comer, Ruth; Dunstone, Nick; Fereday, David; Folland, Chris; Gordon, Margaret; Karpechko, Alexey; Knight, Jeff; MacLachlan, Craig; Smith, Doug; Walker, Brent</p> <p>2016-04-01</p> <p>The northern <span class="hlt">winter</span> of 2015/16 gave rise to the strongest El Niño event since 1997/8. Central and eastern Pacific sea surface temperature anomalies exceeded three degrees and closely resembled the strong El Niño in <span class="hlt">winter</span> of 1982/3. A second feature of this <span class="hlt">winter</span> was a strong westerly phase of the Quasi-Biennial Oscillation and very strong winds in the stratospheric polar night jet. At the surface, intense extratropical circulation anomalies occurred in both the North Pacific and North Atlantic that were consistent with known teleconnections to the observed phases of ENSO and the QBO. The North Atlantic Oscillation was very positive in the early <span class="hlt">winter</span> period (Nov-Dec) and was more blocked in the late <span class="hlt">winter</span>. Initialised climate predictions were able to capture these signals at seasonal lead times. This case study adds to the evidence that north Atlantic circulation exhibits predictability on seasonal timescales, and in this case we show that even aspects of the detailed pattern and sub-seasonal evolution were predicted, providing warning of increased risk of <span class="hlt">extreme</span> events such as the intense rainfall which caused <span class="hlt">extreme</span> flooding in the UK in December.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4990907','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4990907"><span id="translatedtitle">Desert Amplification in a <span class="hlt">Warming</span> Climate</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Zhou, Liming</p> <p>2016-01-01</p> <p>Here I analyze the observed and projected surface temperature anomalies over land between 50°S-50°N for the period 1950–2099 by large-scale ecoregion and find strongest <span class="hlt">warming</span> consistently and persistently seen over driest ecoregions such as the Sahara desert and the Arabian Peninsula during various 30-year periods, pointing to desert amplification in a <span class="hlt">warming</span> climate. This amplification enhances linearly with the global mean greenhouse gases(GHGs) radiative forcing and is attributable primarily to a stronger GHGs-enhanced downward longwave radiation forcing reaching the surface over drier ecoregions as a consequence of a warmer and thus moister atmosphere in response to increasing GHGs. These results indicate that desert amplification may represent a fundamental pattern of global <span class="hlt">warming</span> associated with water vapor feedbacks over land in low- and mid- latitudes where surface <span class="hlt">warming</span> rates depend inversely on ecosystem dryness. It is likely that desert amplification might involve two types of water vapor feedbacks that maximize respectively in the tropical upper troposphere and near the surface over deserts, with both being very dry and thus <span class="hlt">extremely</span> sensitive to changes of water vapor. PMID:27538725</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatSR...631065Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatSR...631065Z"><span id="translatedtitle">Desert Amplification in a <span class="hlt">Warming</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>Zhou, Liming</p> <p>2016-08-01</p> <p>Here I analyze the observed and projected surface temperature anomalies over land between 50°S-50°N for the period 1950–2099 by large-scale ecoregion and find strongest <span class="hlt">warming</span> consistently and persistently seen over driest ecoregions such as the Sahara desert and the Arabian Peninsula during various 30-year periods, pointing to desert amplification in a <span class="hlt">warming</span> climate. This amplification enhances linearly with the global mean greenhouse gases(GHGs) radiative forcing and is attributable primarily to a stronger GHGs-enhanced downward longwave radiation forcing reaching the surface over drier ecoregions as a consequence of a warmer and thus moister atmosphere in response to increasing GHGs. These results indicate that desert amplification may represent a fundamental pattern of global <span class="hlt">warming</span> associated with water vapor feedbacks over land in low- and mid- latitudes where surface <span class="hlt">warming</span> rates depend inversely on ecosystem dryness. It is likely that desert amplification might involve two types of water vapor feedbacks that maximize respectively in the tropical upper troposphere and near the surface over deserts, with both being very dry and thus <span class="hlt">extremely</span> sensitive to changes of water vapor.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27538725','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27538725"><span id="translatedtitle">Desert Amplification in a <span class="hlt">Warming</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>Zhou, Liming</p> <p>2016-08-19</p> <p>Here I analyze the observed and projected surface temperature anomalies over land between 50°S-50°N for the period 1950-2099 by large-scale ecoregion and find strongest <span class="hlt">warming</span> consistently and persistently seen over driest ecoregions such as the Sahara desert and the Arabian Peninsula during various 30-year periods, pointing to desert amplification in a <span class="hlt">warming</span> climate. This amplification enhances linearly with the global mean greenhouse gases(GHGs) radiative forcing and is attributable primarily to a stronger GHGs-enhanced downward longwave radiation forcing reaching the surface over drier ecoregions as a consequence of a warmer and thus moister atmosphere in response to increasing GHGs. These results indicate that desert amplification may represent a fundamental pattern of global <span class="hlt">warming</span> associated with water vapor feedbacks over land in low- and mid- latitudes where surface <span class="hlt">warming</span> rates depend inversely on ecosystem dryness. It is likely that desert amplification might involve two types of water vapor feedbacks that maximize respectively in the tropical upper troposphere and near the surface over deserts, with both being very dry and thus <span class="hlt">extremely</span> sensitive to changes of water vapor.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=PIA05690&hterms=Utopia&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DUtopia','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=PIA05690&hterms=Utopia&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DUtopia"><span id="translatedtitle"><span class="hlt">Winter</span> Clouds Over Mie</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2004-01-01</p> <p>12 March 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) red wide angle image shows late <span class="hlt">winter</span> clouds over the 104 km (65 mi) diameter crater, Mie. Cellular clouds occur in the lower martian atmosphere, surrounding Mie Crater. Their cloudtops are at an altitude that is below the crater rim. Higher than the crater rim occurs a series of lee wave clouds, indicating air circulation moving from west/northwest (left) toward the east/southeast (right). Mie Crater is located in Utopia Planitia, not too far from the Viking 2 landing site, near 48.5 N, 220.4 W. Sunlight illuminates this January 2004 scene from the lower left.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=PIA08095&hterms=spirit&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dspirit','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=PIA08095&hterms=spirit&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dspirit"><span id="translatedtitle">Spirit Scans <span class="hlt">Winter</span> Haven</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>2006-01-01</p> <p><p/> At least three different kinds of rocks await scientific analysis at the place where NASA's Mars Exploration Rover Spirit will likely spend several months of Martian <span class="hlt">winter</span>. They are visible in this picture, which the panoramic camera on Spirit acquired during the rover's 809th sol, or Martian day, of exploring Mars (April 12, 2006). Paper-thin layers of light-toned, jagged-edged rocks protrude horizontally from beneath small sand drifts; a light gray rock with smooth, rounded edges sits atop the sand drifts; and several dark gray to black, angular rocks with vesicles (small holes) typical of hardened lava lie scattered across the sand. <p/> This view is an approximately true-color rendering that combines images taken through the panoramic camera's 753-nanometer, 535-nanometer, and 432-nanometer filters.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.H42D..06D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.H42D..06D"><span id="translatedtitle">Anthropogenic <span class="hlt">Warming</span> Has Increased Drought Risk In California</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Diffenbaugh, N. S.; Swain, D. L.; Touma, D. E.</p> <p>2015-12-01</p> <p>California is currently in the midst of a record-setting drought. The drought began in 2012 and now includes the lowest calendar-year and 12-mo precipitation, the highest annual temperature, and the most <span class="hlt">extreme</span> drought indicators on record. The <span class="hlt">extremely</span> <span class="hlt">warm</span> and dry conditions have led to acute water shortages, groundwater overdraft, critically low streamflow, and enhanced wildfire risk. Analyzing historical climate observations from California, we find that precipitation deficits in California were more than twice as likely to yield drought years if they occurred when conditions were <span class="hlt">warm</span>. We find that although there has not been a substantial change in the probability of either negative or moderately negative precipitation anomalies in recent decades, the occurrence of drought years has been greater in the past two decades than in the preceding century. In addition, the probability that precipitation deficits co-occur with <span class="hlt">warm</span> conditions and the probability that precipitation deficits produce drought have both increased. Climate model experiments with and without anthropogenic forcings reveal that human activities have increased the probability that dry precipitation years are also <span class="hlt">warm</span>. Further, a large ensemble of climate model realizations reveals that additional global <span class="hlt">warming</span> over the next few decades is very likely to create ˜100% probability that any annual-scale dry period is also <span class="hlt">extremely</span> <span class="hlt">warm</span>. We therefore conclude that anthropogenic <span class="hlt">warming</span> is increasing the probability of co-occurring <span class="hlt">warm</span>-dry conditions like those that have created the acute human and ecosystem impacts associated with the "exceptional" 2012-2014 drought in California.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25733875','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25733875"><span id="translatedtitle">Anthropogenic <span class="hlt">warming</span> has increased drought risk in California.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Diffenbaugh, Noah S; Swain, Daniel L; Touma, Danielle</p> <p>2015-03-31</p> <p>California is currently in the midst of a record-setting drought. The drought began in 2012 and now includes the lowest calendar-year and 12-mo precipitation, the highest annual temperature, and the most <span class="hlt">extreme</span> drought indicators on record. The <span class="hlt">extremely</span> <span class="hlt">warm</span> and dry conditions have led to acute water shortages, groundwater overdraft, critically low streamflow, and enhanced wildfire risk. Analyzing historical climate observations from California, we find that precipitation deficits in California were more than twice as likely to yield drought years if they occurred when conditions were <span class="hlt">warm</span>. We find that although there has not been a substantial change in the probability of either negative or moderately negative precipitation anomalies in recent decades, the occurrence of drought years has been greater in the past two decades than in the preceding century. In addition, the probability that precipitation deficits co-occur with <span class="hlt">warm</span> conditions and the probability that precipitation deficits produce drought have both increased. Climate model experiments with and without anthropogenic forcings reveal that human activities have increased the probability that dry precipitation years are also <span class="hlt">warm</span>. Further, a large ensemble of climate model realizations reveals that additional global <span class="hlt">warming</span> over the next few decades is very likely to create ∼ 100% probability that any annual-scale dry period is also <span class="hlt">extremely</span> <span class="hlt">warm</span>. We therefore conclude that anthropogenic <span class="hlt">warming</span> is increasing the probability of co-occurring <span class="hlt">warm</span>-dry conditions like those that have created the acute human and ecosystem impacts associated with the "exceptional" 2012-2014 drought in California.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ThApC.tmp...21A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ThApC.tmp...21A"><span id="translatedtitle">Trends in mean and <span class="hlt">extreme</span> temperatures over Ibadan, Southwest Nigeria</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Abatan, Abayomi A.; Osayomi, Tolulope; Akande, Samuel O.; Abiodun, Babatunde J.; Gutowski, William J.</p> <p>2017-01-01</p> <p>In recent times, Ibadan has been experiencing an increase in mean temperature which appears to be linked to anthropogenic global <span class="hlt">warming</span>. Previous studies have indicated that the <span class="hlt">warming</span> may be accompanied by changes in <span class="hlt">extreme</span> events. This study examined trends in mean and <span class="hlt">extreme</span> temperatures over Ibadan during 1971-2012 at annual and seasonal scales using the high-resolution atmospheric reanalysis from European Centre for Medium-Range Weather Forecasts (ECMWF) twentieth-century dataset (ERA-20C) at 15 grid points. Magnitudes of linear trends in mean and <span class="hlt">extreme</span> temperatures and their statistical significance were calculated using ordinary least squares and Mann-Kendall rank statistic tests. The results show that Ibadan has witnessed an increase in annual and seasonal mean minimum temperatures. The annual mean maximum temperature exhibited a non-significant decline in most parts of Ibadan. While trends in cold <span class="hlt">extremes</span> at annual scale show <span class="hlt">warming</span>, trends in coldest night show greater <span class="hlt">warming</span> than in coldest day. At the seasonal scale, we found that Ibadan experienced a mix of positive and negative trends in absolute <span class="hlt">extreme</span> temperature indices. However, cold <span class="hlt">extremes</span> show the largest trend magnitudes, with trends in coldest night showing the greatest <span class="hlt">warming</span>. The results compare well with those obtained from a limited number of stations. This study should inform decision-makers and urban planners about the ongoing <span class="hlt">warming</span> in Ibadan.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1986Icar...66..366D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1986Icar...66..366D"><span id="translatedtitle">Polar <span class="hlt">warming</span> in the middle atmosphere of Mars</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Deming, D.; Mumma, M. J.; Espenak, F.; Kostiuk, T.; Zipoy, D.</p> <p>1986-05-01</p> <p>During the 1984 Mars opposition, ground-based laser heterodyne spectroscopy was obtained for the nonthermal core emission of the 10.33-micron R(8) and 10.72-micron P(32) lines of C-12(O-16)2 at 23 locations on the Martian disk. It is deduced on the basis of these data that the temperature of the middle Martian atmosphere varies with latitude, and a meridional gradient of 0.4-0.9 K/deg latitude is indicated. The highest temperatures are noted to lie at high latitudes in the <span class="hlt">winter</span> hemisphere; as in the terrestrial case of seasonal effects at the menopause, this <span class="hlt">winter</span> polar <span class="hlt">warming</span> in the Martian middle atmosphere requires departures from radiative equilibrium. Two-dimensional circulation model comparisons with these results indicate that atmospheric dust may enhance this dynamical heating at high <span class="hlt">winter</span> latitudes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19860061152&hterms=Menopause&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DMenopause','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19860061152&hterms=Menopause&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DMenopause"><span id="translatedtitle">Polar <span class="hlt">warming</span> in the middle atmosphere of Mars</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Deming, D.; Mumma, M. J.; Espenak, F.; Kostiuk, T.; Zipoy, D.</p> <p>1986-01-01</p> <p>During the 1984 Mars opposition, ground-based laser heterodyne spectroscopy was obtained for the nonthermal core emission of the 10.33-micron R(8) and 10.72-micron P(32) lines of C-12(O-16)2 at 23 locations on the Martian disk. It is deduced on the basis of these data that the temperature of the middle Martian atmosphere varies with latitude, and a meridional gradient of 0.4-0.9 K/deg latitude is indicated. The highest temperatures are noted to lie at high latitudes in the <span class="hlt">winter</span> hemisphere; as in the terrestrial case of seasonal effects at the menopause, this <span class="hlt">winter</span> polar <span class="hlt">warming</span> in the Martian middle atmosphere requires departures from radiative equilibrium. Two-dimensional circulation model comparisons with these results indicate that atmospheric dust may enhance this dynamical heating at high <span class="hlt">winter</span> latitudes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRD..121.9441G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRD..121.9441G"><span id="translatedtitle">Interannual modulation of East African early short rains by the <span class="hlt">winter</span> Arctic Oscillation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gong, Dao-Yi; Guo, Dong; Mao, Rui; Yang, Jing; Gao, Yongqi; Kim, Seong-Joong</p> <p>2016-08-01</p> <p>In the present study, we analyzed the interannual linkage between the boreal <span class="hlt">winter</span> Arctic Oscillation (AO) and East African early short rains. When the Indian Ocean Dipole and El Niño-Southern Oscillation variance are excluded by linear regression, the boreal <span class="hlt">winter</span> AO index is significantly correlated with the October East African precipitation over the domain of 5°N-5°S and 35°-45°E for the period 1979-2014, r =+ 0.46. The upper ocean heat content likely acts as a medium that links the AO and East African precipitation. Significant subsurface <span class="hlt">warming</span> and positive upper ocean heat content anomalies occur over the western Indian Ocean during the autumn following positive AO <span class="hlt">winters</span>, which enriches the atmospheric moisture, intensifies convection, and enhances precipitation. Oceanic dynamics play a key role in causing this subsurface <span class="hlt">warming</span>. <span class="hlt">Winter</span> AO-related atmospheric circulation creates anomalous wind stress, which forces a downwelling oceanic Rossby wave between 60°-75°E and 5°-10°S, where the thermocline significantly deepens. This Rossby wave propagates westward and accompanies significant subsurface <span class="hlt">warming</span> along the thermocline. The Rossby wave arrives at the western Indian Ocean in the late summer, significantly <span class="hlt">warming</span> the region to the west of 55°E at a depth of 60-100 m. This <span class="hlt">warming</span> remains significant through October. Correspondingly, the upper ocean heat content significantly increases by approximately 2-3 × 108 J m-2 in the region west of 60°E between 5° and 10°S. The role of these oceanic dynamics in linking the <span class="hlt">winter</span> AO, and anomalous subsurface <span class="hlt">warming</span> was tested by numerical experiments with an oceanic general circulation model. The experiments were performed with the forcing of AO-related wind stress anomalies over the Indian Ocean in the <span class="hlt">winter</span>. The oceanic Rossby wave generated in the central Indian Ocean during boreal <span class="hlt">winter</span>, the consequent subsurface <span class="hlt">warming</span>, and the anomalous upper ocean heat content in October over the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25824529','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25824529"><span id="translatedtitle">Local cooling and <span class="hlt">warming</span> effects of forests based on satellite observations.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Li, Yan; Zhao, Maosheng; Motesharrei, Safa; Mu, Qiaozhen; Kalnay, Eugenia; Li, Shuangcheng</p> <p>2015-03-31</p> <p>The biophysical effects of forests on climate have been extensively studied with climate models. However, models cannot accurately reproduce local climate effects due to their coarse spatial resolution and uncertainties, and field observations are valuable but often insufficient due to their limited coverage. Here we present new evidence acquired from global satellite data to analyse the biophysical effects of forests on local climate. Results show that tropical forests have a strong cooling effect throughout the year; temperate forests show moderate cooling in summer and moderate <span class="hlt">warming</span> in <span class="hlt">winter</span> with net cooling annually; and boreal forests have strong <span class="hlt">warming</span> in <span class="hlt">winter</span> and moderate cooling in summer with net <span class="hlt">warming</span> annually. The spatiotemporal cooling or <span class="hlt">warming</span> effects are mainly driven by the two competing biophysical effects, evapotranspiration and albedo, which in turn are strongly influenced by rainfall and snow. Implications of our satellite-based study could be useful for informing local forestry policies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.7000W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.7000W"><span id="translatedtitle">Tropospheric circulation during the early twentieth century Arctic <span class="hlt">warming</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wegmann, Martin; Brönnimann, Stefan; Compo, Gilbert P.</p> <p>2016-04-01</p> <p>The early twentieth century Arctic <span class="hlt">warming</span> (ETCAW) between 1920-1940 is an exceptional feature of climate dynamics in the last century and its <span class="hlt">warming</span> rate was only recently matched by anthropogenic global <span class="hlt">warming</span> amplification in the Arctic region. However, atmospheric <span class="hlt">warming</span> during the ETCAW was strongest in the mid-troposphere and is believed to be triggered by an exceptional case of natural climate variability. Nevertheless, ultimate mechanisms and causes for the ETCAW are still under discussion. Here we use state of the art multi member global circulation models, reanalysis and reconstruction datasets to investigate the internal atmospheric dynamics of the ETCAW. We use these gridded datasets to investigate the role of boreal <span class="hlt">winter</span> mid-tropospheric heat transport and circulation in providing the energy for the large scale <span class="hlt">warming</span>. Analysing heat flux components and regional differences, it was found that climate models are not able to reproduce the heat flux evolution shown by reanalysis and reconstruction datasets. These datasets compute an increase of stationary eddy heat flux and a decrease of transient eddy heat flux during the ETCAW. Moreover, tropospheric circulation analysis revealed the important role of both the Atlantic and the Pacific sectors in the convergence of southerly air masses into the Arctic during the <span class="hlt">warming</span> event. Subsequently, it could be shown that the internal dynamics of the atmosphere played a major role in the formation in the ETCAW.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2992703','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2992703"><span id="translatedtitle">Diving through the thermal window: implications for a <span class="hlt">warming</span> world</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Campbell, Hamish A.; Dwyer, Ross G.; Gordos, Matthew; Franklin, Craig E.</p> <p>2010-01-01</p> <p>Population decline and a shift in the geographical distribution of some ectothermic animals have been attributed to climatic <span class="hlt">warming</span>. Here, we show that rises in water temperature of a few degrees, while within the thermal window for locomotor performance, may be detrimental to diving behaviour in air-breathing ectotherms (turtles, crocodilians, marine iguanas, amphibians, snakes and lizards). Submergence times and internal and external body temperature were remotely recorded from freshwater crocodiles (Crocodylus johnstoni) while they free-ranged throughout their natural habitat in summer and <span class="hlt">winter</span>. During summer, the crocodiles' mean body temperature was 5.2 ± 0.1°C higher than in <span class="hlt">winter</span> and the largest proportion of total dive time was composed of dive durations approximately 15 min less than in <span class="hlt">winter</span>. Diving beyond 40 min during summer required the crocodiles to exponentially increase the time they spent on the surface after the dive, presumably to clear anaerobic debt. The relationship was not as significant in <span class="hlt">winter</span>, even though a greater proportion of dives were of a longer duration, suggesting that diving lactate threshold (DLT) was reduced in summer compared with <span class="hlt">winter</span>. Additional evidence for a reduced DLT in summer was derived from the stronger influence body mass exerted upon dive duration, compared to <span class="hlt">winter</span>. The results demonstrate that the higher summer body temperature increased oxygen demand during the dive, implying that thermal acclimatization of the diving metabolic rate was inadequate. If the study findings are common among air-breathing diving ectotherms, then long-term <span class="hlt">warming</span> of the aquatic environment may be detrimental to behavioural function and survivorship. PMID:20610433</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20610433','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20610433"><span id="translatedtitle">Diving through the thermal window: implications for a <span class="hlt">warming</span> world.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Campbell, Hamish A; Dwyer, Ross G; Gordos, Matthew; Franklin, Craig E</p> <p>2010-12-22</p> <p>Population decline and a shift in the geographical distribution of some ectothermic animals have been attributed to climatic <span class="hlt">warming</span>. Here, we show that rises in water temperature of a few degrees, while within the thermal window for locomotor performance, may be detrimental to diving behaviour in air-breathing ectotherms (turtles, crocodilians, marine iguanas, amphibians, snakes and lizards). Submergence times and internal and external body temperature were remotely recorded from freshwater crocodiles (Crocodylus johnstoni) while they free-ranged throughout their natural habitat in summer and <span class="hlt">winter</span>. During summer, the crocodiles' mean body temperature was 5.2±0.1°C higher than in <span class="hlt">winter</span> and the largest proportion of total dive time was composed of dive durations approximately 15 min less than in <span class="hlt">winter</span>. Diving beyond 40 min during summer required the crocodiles to exponentially increase the time they spent on the surface after the dive, presumably to clear anaerobic debt. The relationship was not as significant in <span class="hlt">winter</span>, even though a greater proportion of dives were of a longer duration, suggesting that diving lactate threshold (DLT) was reduced in summer compared with <span class="hlt">winter</span>. Additional evidence for a reduced DLT in summer was derived from the stronger influence body mass exerted upon dive duration, compared to <span class="hlt">winter</span>. The results demonstrate that the higher summer body temperature increased oxygen demand during the dive, implying that thermal acclimatization of the diving metabolic rate was inadequate. If the study findings are common among air-breathing diving ectotherms, then long-term <span class="hlt">warming</span> of the aquatic environment may be detrimental to behavioural function and survivorship.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatSR...638287B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatSR...638287B"><span id="translatedtitle">Magnitude and pattern of Arctic <span class="hlt">warming</span> governed by the seasonality of radiative forcing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bintanja, R.; Krikken, F.</p> <p>2016-12-01</p> <p>Observed and projected climate <span class="hlt">warming</span> is strongest in the Arctic regions, peaking in autumn/<span class="hlt">winter</span>. Attempts to explain this feature have focused primarily on identifying the associated climate feedbacks, particularly the ice-albedo and lapse-rate feedbacks. Here we use a state-of-the-art global climate model in idealized seasonal forcing simulations to show that Arctic <span class="hlt">warming</span> (especially in <span class="hlt">winter</span>) and sea ice decline are particularly sensitive to radiative forcing in spring, during which the energy is effectively ‘absorbed’ by the ocean (through sea ice melt and ocean <span class="hlt">warming</span>, amplified by the ice-albedo feedback) and consequently released to the lower atmosphere in autumn and <span class="hlt">winter</span>, mainly along the sea ice periphery. In contrast, <span class="hlt">winter</span> radiative forcing causes a more uniform response centered over the Arctic Ocean. This finding suggests that intermodel differences in simulated Arctic (<span class="hlt">winter</span>) <span class="hlt">warming</span> can to a considerable degree be attributed to model uncertainties in Arctic radiative fluxes, which peak in summer.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5133621','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5133621"><span id="translatedtitle">Magnitude and pattern of Arctic <span class="hlt">warming</span> governed by the seasonality of radiative forcing</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Bintanja, R.; Krikken, F.</p> <p>2016-01-01</p> <p>Observed and projected climate <span class="hlt">warming</span> is strongest in the Arctic regions, peaking in autumn/<span class="hlt">winter</span>. Attempts to explain this feature have focused primarily on identifying the associated climate feedbacks, particularly the ice-albedo and lapse-rate feedbacks. Here we use a state-of-the-art global climate model in idealized seasonal forcing simulations to show that Arctic <span class="hlt">warming</span> (especially in <span class="hlt">winter</span>) and sea ice decline are particularly sensitive to radiative forcing in spring, during which the energy is effectively ‘absorbed’ by the ocean (through sea ice melt and ocean <span class="hlt">warming</span>, amplified by the ice-albedo feedback) and consequently released to the lower atmosphere in autumn and <span class="hlt">winter</span>, mainly along the sea ice periphery. In contrast, <span class="hlt">winter</span> radiative forcing causes a more uniform response centered over the Arctic Ocean. This finding suggests that intermodel differences in simulated Arctic (<span class="hlt">winter</span>) <span class="hlt">warming</span> can to a considerable degree be attributed to model uncertainties in Arctic radiative fluxes, which peak in summer. PMID:27910905</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004GBioC..18.3003S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004GBioC..18.3003S"><span id="translatedtitle">Response of ocean ecosystems to climate <span class="hlt">warming</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sarmiento, J. L.; Slater, R.; Barber, R.; Bopp, L.; Doney, S. C.; Hirst, A. C.; Kleypas, J.; Matear, R.; Mikolajewicz, U.; Monfray, P.; Soldatov, V.; Spall, S. A.; Stouffer, R.</p> <p>2004-09-01</p> <p>We examine six different coupled climate model simulations to determine the ocean biological response to climate <span class="hlt">warming</span> between the beginning of the industrial revolution and 2050. We use vertical velocity, maximum <span class="hlt">winter</span> mixed layer depth, and sea ice cover to define six biomes. Climate <span class="hlt">warming</span> leads to a contraction of the highly productive marginal sea ice biome by 42% in the Northern Hemisphere and 17% in the Southern Hemisphere, and leads to an expansion of the low productivity permanently stratified subtropical gyre biome by 4.0% in the Northern Hemisphere and 9.4% in the Southern Hemisphere. In between these, the subpolar gyre biome expands by 16% in the Northern Hemisphere and 7% in the Southern Hemisphere, and the seasonally stratified subtropical gyre contracts by 11% in both hemispheres. The low-latitude (mostly coastal) upwelling biome area changes only modestly. Vertical stratification increases, which would be expected to decrease nutrient supply everywhere, but increase the growing season length in high latitudes. We use satellite ocean color and climatological observations to develop an empirical model for predicting chlorophyll from the physical properties of the global <span class="hlt">warming</span> simulations. Four features stand out in the response to global <span class="hlt">warming</span>: (1) a drop in chlorophyll in the North Pacific due primarily to retreat of the marginal sea ice biome, (2) a tendency toward an increase in chlorophyll in the North Atlantic due to a complex combination of factors, (3) an increase in chlorophyll in the Southern Ocean due primarily to the retreat of and changes at the northern boundary of the marginal sea ice zone, and (4) a tendency toward a decrease in chlorophyll adjacent to the Antarctic continent due primarily to freshening within the marginal sea ice zone. We use three different primary production algorithms to estimate the response of primary production to climate <span class="hlt">warming</span> based on our estimated chlorophyll concentrations. The three algorithms give</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('https://www.ncbi.nlm.nih.gov/pubmed/21392331','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21392331"><span id="translatedtitle">Direct impacts of recent climate <span class="hlt">warming</span> on insect populations.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Robinet, Christelle; Roques, Alain</p> <p>2010-06-01</p> <p>Effects of recent climate change have already been detected in many species, and, in particular, in insects. The present paper reviews the key impacts of global <span class="hlt">warming</span> on insect development and dispersal. The effects of climate change appear to be much more complex than a simple linear response to an average increase in temperature. They can differ between seasons and bioclimatic regions. Earlier flight periods, enhanced <span class="hlt">winter</span> survival and acceleration of development rates are the major insect responses. Differential response of insects and hosts to <span class="hlt">warming</span> up might also lead to disruption of their phenological synchrony, but adaptive genetic processes are likely to quickly restore this synchrony. In a number of cases, <span class="hlt">warming</span> results in removing or relocating the barriers that limit present species' ranges. It is also likely to facilitate the establishment and spread of invasive alien species. Finally, knowledge gaps are identified and future research interests are suggested.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19850012119&hterms=wine&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dwine','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19850012119&hterms=wine&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dwine"><span id="translatedtitle">The Middle Atmosphere Program: <span class="hlt">Winter</span> In Northern Europe (MAP/WINE)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Vonzahn, U.</p> <p>1982-01-01</p> <p>The goals of map/wind (<span class="hlt">winter</span> in Northern Europe) are to better understand: (1) the interaction of planetary waves of tropospheric origin; (2) the temporal and spatial development of sudden stratospheric <span class="hlt">warmings</span>; (3) the temporal and spatial development of mesospheric cooling events in conjunction with stratospheric <span class="hlt">warmings</span>; (4) the vertical and horizontal transport of minor constituents; (5) the effects on the chemistry of neutral and charged species of the large temperature changes occurring during stratospheric <span class="hlt">warmings</span> and mesospheric cooling; (6) sources of turbulent energy; (7) the temporal and spatial development of turbulent layers; and (8) the contributions of dynamical processes to the heating and cooling of the mesospheric and turbopause region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.C53A0768H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.C53A0768H"><span id="translatedtitle">Changes in Seasonal and <span class="hlt">Extreme</span> Arctic Cyclone Events in the CMIP5 Climate Models</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hori, M. E.</p> <p>2015-12-01</p> <p>Cyclone activities are governed by many boundary conditions, such as the underlying SST or sea ice, the relative heating between the continent and the ocean, and their relative location against the jet stream to name a few. All these factors and their seasonal march is prone to change under the future global <span class="hlt">warming</span> condition. Especially in the Arctic, the timing of sea ice melting and freezing, seasonal change in snow cover, and the location of upper level jets all contribute towards a change in cyclone seasonal distribution and <span class="hlt">extreme</span> events. Here, we use a Langrangean method of detecting cyclones and their activity under the historical and rcp 4.5 scenario of 8 CMIP5 climate models to assess the change in Arctic cyclone activities. We find that while the models show weaker cyclone activities than observation and inter-model difference is large in some cases, they simulate the seasonal cycle and <span class="hlt">extreme</span> events reasonably well. In the <span class="hlt">winter</span> season under the global <span class="hlt">warming</span> scenario, many models exhibits a northeastward shift in mid-latitude storm track resulting in mode cyclones entering the Arctic from the mid-latitudes. There is also a marked increase in the number of cyclones in the Barents/Kara Sea where correlation with sea ice is suspected. During the summer season, a large change in the Arctic cyclone activity located near the North Pole is evident in many models. This change in Arctic cyclone is due to contribution of more cyclogenesis within the Arctic circle. In this presentation, we also look at other seasons and the seasonal march of the cyclone activity within the Arctic and its interaction with the mid-latitudes. We also document the change in <span class="hlt">extreme</span> events under the climate models.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27650278','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27650278"><span id="translatedtitle">The effect of <span class="hlt">winter</span> length on survival and duration of dormancy of four sympatric species of Rhagoletis exploiting plants with different fruiting phenology.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Rull, J; Tadeo, E; Lasa, R; Aluja, M</p> <p>2016-12-01</p> <p>Dormancy has been thoroughly studied for several species of economic importance in the genus Rhagoletis in temperate areas of North America and Europe. Much less is known on life history regulation for species inhabiting high-elevation areas in the subtropics at the southern <span class="hlt">extreme</span> of their geographical range. Host plant phenology has been found to play a key role in generating allochronic isolation among sibling species and host races of Rhagoletis in the course of sympatric speciation, and has important implications for pest management. We compare the effect of <span class="hlt">winter</span> length on survival to adult eclosion and dormancy duration among four species of Rhagoletis (three of them sympatric) exploiting hosts with different fruiting phenology in subtropical isolated highlands. Survival and duration of dormancy was found to be different among the four species. At 24°C, a very small proportion (<1%) of R. pomonella, R. turpiniae and R. zoqui completed development without becoming dormant, while in the case of R. solanophaga the majority of the population emerged after development within 40 days of pupation. Also, a large proportion of braconid parasitoids infesting Rhagoletis eggs and larvae emerged as adults without becoming dormant. Greatest survival after artificial <span class="hlt">winter</span> was obtained for R. pomonella (50-60%) and R. zoqui (30%) after only four weeks at 5°C (a third of the time reported for studies on northern R. pomonella), while R. turpiniae, under identical environmental conditions experienced low adult emergence, and highest survival (11%) was recorded for flies exposed to 5°C during 10 and 12 weeks. For R. pomonella, there was a strong positive relationship between <span class="hlt">winter</span> length and time to post-<span class="hlt">winter</span> adult eclosion that was not observed for R. zoqui. In sum, for R. pomonella, mild <span class="hlt">winters</span> in highland subtropical areas appear to select for flies better able to withstand longer periods of <span class="hlt">warm</span> temperature before <span class="hlt">winter</span> than flies exploiting late fruiting hosts</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/5465207','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5465207"><span id="translatedtitle">Greenhouse <span class="hlt">warming</span> still coming</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kerr, R.A.</p> <p>1986-05-02</p> <p>The growing store of carbon dioxide in the earth's atmosphere from the burning of fossil fuels and deforestation is a far larger and more pervasive problem than acid rain. The predictions of the latest models that have been applied to the problem, called GCM-mixed-layer ocean models, predict a global temperature increase between 3.5 and 4.2 degrees Celsius. They predict that the <span class="hlt">warming</span> will be larger near the poles than near the equator. They also predict increases and decreases in precipitation depending on location, the largest changes being between 30/sup 0/N and 30/sup 0/S. If CO/sub 2/ and trace gas concentrations continue to rise as projected and model calculations are essentially correct, the increasing global scale <span class="hlt">warming</span> should become much more evident over the next few decades. 1 figure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27768357','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27768357"><span id="translatedtitle"><span class="hlt">Warm</span> Little Inflaton.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bastero-Gil, Mar; Berera, Arjun; Ramos, Rudnei O; Rosa, João G</p> <p>2016-10-07</p> <p>We show that inflation can naturally occur at a finite temperature T>H that is sustained by dissipative effects, when the inflaton field corresponds to a pseudo Nambu-Goldstone boson of a broken gauge symmetry. Similar to the Little Higgs scenarios for electroweak symmetry breaking, the flatness of the inflaton potential is protected against both quadratic divergences and the leading thermal corrections. We show that, nevertheless, nonlocal dissipative effects are naturally present and are able to sustain a nearly thermal bath of light particles despite the accelerated expansion of the Universe. As an example, we discuss the dynamics of chaotic <span class="hlt">warm</span> inflation with a quartic potential and show that the associated observational predictions are in very good agreement with the latest Planck results. This model constitutes the first realization of <span class="hlt">warm</span> inflation requiring only a small number of fields; in particular, the inflaton is directly coupled to just two light fields.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhRvL.117o1301B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhRvL.117o1301B"><span id="translatedtitle"><span class="hlt">Warm</span> Little Inflaton</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bastero-Gil, Mar; Berera, Arjun; Ramos, Rudnei O.; Rosa, João G.</p> <p>2016-10-01</p> <p>We show that inflation can naturally occur at a finite temperature T >H that is sustained by dissipative effects, when the inflaton field corresponds to a pseudo Nambu-Goldstone boson of a broken gauge symmetry. Similar to the Little Higgs scenarios for electroweak symmetry breaking, the flatness of the inflaton potential is protected against both quadratic divergences and the leading thermal corrections. We show that, nevertheless, nonlocal dissipative effects are naturally present and are able to sustain a nearly thermal bath of light particles despite the accelerated expansion of the Universe. As an example, we discuss the dynamics of chaotic <span class="hlt">warm</span> inflation with a quartic potential and show that the associated observational predictions are in very good agreement with the latest Planck results. This model constitutes the first realization of <span class="hlt">warm</span> inflation requiring only a small number of fields; in particular, the inflaton is directly coupled to just two light fields.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA363890','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA363890"><span id="translatedtitle">Military Implications of Global <span class="hlt">Warming</span>.</span></a></p> <p><a target="_blank" href="https://publicaccess.dtic.mil/psm/api/service/search/search">DTIC Science & Technology</a></p> <p></p> <p>2007-11-02</p> <p>U.S. environmental issues also have important global implications. This paper analyzes current U.S. Policy as it pertains to global <span class="hlt">warming</span> and climate...for military involvement to reduce global <span class="hlt">warming</span> . Global <span class="hlt">warming</span> and other environmental issues are important to the U.S. military. As the United</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140011285','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140011285"><span id="translatedtitle">On the Role of SST Forcing in the 2011 and 2012 <span class="hlt">Extreme</span> U.S. Heat and Drought: A Study in Contrasts</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; Koster, Randal; Ham, Yoo-Geun; Suarez, Max</p> <p>2013-01-01</p> <p>This study compares the <span class="hlt">extreme</span> heat and drought that developed over the United States in 2011 and 2012 with a focus on the role of SST forcing. Experiments with the NASA GEOS-5 atmospheric general circulation model show that the <span class="hlt">winter</span>/spring response over the U.S. to the Pacific SST is remarkably similar for the two years despite substantial differences in the tropical Pacific SST. As such, the pronounced <span class="hlt">winter</span> and early spring temperature differences between the two years (warmth confined to the south in 2011 and covering much of the continent in 2012) primarily reflect differences in the contributions from the Atlantic and Indian Oceans, with both acting to cool the east and upper mid-west during 2011, while during 2012 the Indian Ocean reinforced the Pacific-driven continental-wide <span class="hlt">warming</span> and the Atlantic played a less important role. During late spring and summer of 2011 the tropical Pacific SST force a continued <span class="hlt">warming</span> and drying over the southern U.S., though considerably weaker than observed. Nevertheless, the observed anomalies fall within the models intra-ensemble spread. In contrast, the rapid development of intense heat and drying over the central U.S. during June and July of 2012 falls outside the models intra-ensemble spread. The response to the SST (a northward expansion of a modest summer <span class="hlt">warming</span> linked to the Atlantic) gives little indication that 2012 would produce record-breaking precipitation deficits and heat in the central Great Plains. A diagnosis of the 2012 observed circulation anomalies shows that the most <span class="hlt">extreme</span> heat and drought was tied to the development of a stationary Rossby wave and an associated anomalous upper tropospheric high maintained by weather transients.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70021178','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70021178"><span id="translatedtitle">Long-term experimental manipulation of <span class="hlt">winter</span> snow regime and summer temperature in arctic and alpine tundra</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Walker, M.D.; Walker, D.A.; Welker, J.M.; Arft, A.M.; Bardsley, T.; Brooks, P.D.; Fahnestock, J.T.; Jones, M.H.; Losleben, M.; Parsons, A.N.; Seastedt, T.R.; Turner, P.L.</p> <p>1999-01-01</p> <p>Three 60 m long, 2.8 m high snowfences have been erected to study long-term effects of changing <span class="hlt">winter</span> snow conditions on arctic and alpine tundra. This paper describes the experimental design and short-term effects. Open-top fiberglass <span class="hlt">warming</span> chambers are placed along the experimental snow gradients and in controls areas outside the fences; each <span class="hlt">warming</span> plot is paired with an unwarmed plot. The purpose of the experiment is to examine short- and long-term changes to the integrated physical-biological systems under simultaneous changes of <span class="hlt">winter</span> snow regime and summer temperature, as part of the Long-Term Ecological Research network and the International Tundra Experiment. The sites were at Niwot Ridge, Colorado, a temperate high altitude site in the Colorado Rockies, and Toolik Lake, Alaska, a high-latitude site. Initial results indicate that although experimental designs are essentially identical at the arctic and alpine sites, experimental effects are different. The drift at Niwot Ridge lasts much longer than do the Toolik Lake drifts, so that the Niwot Ridge fence affects both summer and <span class="hlt">winter</span> conditions, whereas the Toolik Lake fence affects primarily <span class="hlt">winter</span> conditions. The temperature experiment also differs in effect between the sites. Although the average temperature increase at the two sites is similar (daily increase 1.5oC at Toolik and 1.9oC at Niwot Ridge), at Toolik Lake there is only minor diurnal variation, whereas at Niwot Ridge the daytime increases are <span class="hlt">extreme</span> on sunny days (as much as 7-10oC), and minimum nighttime temperatures in the chambers are often slightly cooler than ambient (by about 1oC). The experimental drifts resulted in wintertime increases in temperature and CO2 flux. Temperatures under the deep drifts were much more consistent and warmer than in control areas, and at Niwot Ridge remained very close to 0oC all <span class="hlt">winter</span>. These increased temperatures were likely responsible for observed increases in system carbon loss. Initial changes</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMGC41G..02H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMGC41G..02H"><span id="translatedtitle">Changes in U.S. Temperature <span class="hlt">Extremes</span> under Increased CO2 in Millennial-scale Climate Simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Huang, W. K.; Stein, M.; Moyer, E. J.; Sun, S.; McInerney, D.</p> <p>2015-12-01</p> <p>Changes in <span class="hlt">extreme</span> weather may produce some of the largest societal impacts from anthropogenic climate change: present-day weather damages are dominated by rare events that happen only every several decades or more. However, it is intrinsically difficult to estimate changes in those rare events from the short observational record. We therefore look for insight to climate models, where we can generate long simulations. In this work we use millennial runs from the Community Climate System Model version 3 (CCSM3) in equilibrated pre-industrial and future (700 and 1400 ppm CO2) conditions. We examine both how <span class="hlt">extremes</span> change using 1000-year timeseries, and how well these changes can be estimated based on shorter pieces of these runs. We estimate changes to distributions of future annual temperature <span class="hlt">extremes</span> (wintertime minima and summertime maxima) in the contiguous United States by fitting generalized <span class="hlt">extreme</span> value (GEV) distributions using the block maxima approach. Our results show that the magnitude of summer <span class="hlt">warm</span> <span class="hlt">extremes</span> largely shifts in accordance with mean shifts in summertime temperatures, and their distribution does not otherwise change significantly. In contrast, <span class="hlt">winter</span> cold <span class="hlt">extremes</span> <span class="hlt">warm</span> more than mean shifts in wintertime temperatures, with changes in spread and skewness at inland locations that lead to substantial changes in tail behavior. We then examine uncertainties that result from using shorter model runs. In principle, GEV modeling allows us to predict infrequent events using timeseries shorter than the recurrence frequency of those events. To investigate how well this approach works in practice, we estimate 20-, 50-, and 100-year <span class="hlt">extreme</span> events, first in the full 1000-year model timeseries and then using segments of 20 and 50 years. We find that even with GEV modeling, timeseries that are of comparable length or shorter than the return period of interest can lead to very poor estimates. These results suggest caution when attempting to use short</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6571494','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6571494"><span id="translatedtitle"><span class="hlt">Winter</span> fuels report</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Not Available</p> <p>1990-10-04</p> <p>The <span class="hlt">Winter</span> Fuels Report is intended to provide concise, timely information to the industry, the press, policymakers, consumers, analysts, and state and local governments on the following topics: distillate fuel oil net production, imports and stocks for all PADD's and product supplied on a US level; propane net production, imports and stocks for Petroleum Administration for Defense Districts (PADD) I, II, and III; natural gas supply and disposition, underground storage, and consumption for all PADD's; residential and wholesale pricing data for propane and heating oil for those states participating in the joint Energy Information Administration (EIA)/State Heating Oil and Propane Program; crude oil price comparisons for the United States and selected cities; and US total heating degree-days by city. This report will be published weekly by the EIA starting the first week in October 1990 and will continue until the first week in April 1991. The data will also be available electronically after 5:00 p.m. on Thursday during the heating season through the EIA Electronic Publication System (EPUB). 12 tabs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017GeoRL..44..409L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017GeoRL..44..409L"><span id="translatedtitle">Sea ice thickness and recent Arctic <span class="hlt">warming</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lang, Andreas; Yang, Shuting; Kaas, Eigil</p> <p>2017-01-01</p> <p>The climatic impact of increased Arctic sea ice loss has received growing attention in the last years. However, little focus has been set on the role of sea ice thickness, although it strongly determines surface heat fluxes. Here ensembles of simulations using the EC-Earth atmospheric model (Integrated Forecast System) are performed and analyzed to quantify the atmospheric impacts of Arctic sea ice thickness change since 1982 as revealed by the sea ice model assimilation Global Ice-Ocean Modeling and Assimilation System. Results show that the recent sea ice thinning has significantly affected the Arctic climate, while remote atmospheric responses are less pronounced owing to a high internal atmospheric variability. Locally, the sea ice thinning results in enhancement of near-surface <span class="hlt">warming</span> of about 1°C per decade in <span class="hlt">winter</span>, which is most pronounced over marginal sea ice areas with thin ice. This leads to an increase of the Arctic amplification factor by 37%.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA500986','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA500986"><span id="translatedtitle">Global <span class="hlt">Warming</span>: Its Implications for U.S. National Security Policy</span></a></p> <p><a target="_blank" href="https://publicaccess.dtic.mil/psm/api/service/search/search">DTIC Science & Technology</a></p> <p></p> <p>2009-03-19</p> <p>give a voice to those 16 makes even very is theory appears global <span class="hlt">warming</span> . 6 decreased between 1940 and the early ’70s, increased again until the ’90s...get worse in the coming decades. The IPCC reports that even slight increases in global <span class="hlt">warming</span> will negatively impact agriculture production in...hurricanes, the IPCC has predicted an increase in heavy precipitation events as a result of global <span class="hlt">warming</span> .43 The price of increased <span class="hlt">extreme</span> weather is</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JCos...2210106S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JCos...2210106S"><span id="translatedtitle">Perihelion precession, polar ice and global <span class="hlt">warming</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Steel, Duncan</p> <p>2013-03-01</p> <p>The increase in mean global temperature over the past 150 years is generally ascribed to human activities, in particular the rises in the atmospheric mixing ratios of carbon dioxide and other greenhouse gases since the Industrial Revolution began. Whilst it is thought that ice ages and interglacial periods are mainly initiated by multi-millennial variations in Earth's heliocentric orbit and obliquity, shorter-term orbital variations and consequent observable climatic effects over decadal/centurial timescales have not been considered significant causes of contemporary climate change compared to anthropogenic influences. Here it is shown that the precession of perihelion occurring over a century substantially affects the intra-annual variation of solar radiation influx at different locations, especially higher latitudes, with northern and southern hemispheres being subject to contrasting insolation changes. This north/south asymmetry has grown since perihelion was aligned with the <span class="hlt">winter</span> solstice seven to eight centuries ago, and must cause enhanced year-on-year springtime melting of Arctic (but not Antarctic) ice and therefore feedback <span class="hlt">warming</span> because increasing amounts of land and open sea are denuded of high-albedo ice and snow across boreal summer and into autumn. The accelerating sequence of insolation change now occurring as perihelion moves further into boreal <span class="hlt">winter</span> has not occurred previously during the Holocene and so would not have been observed before by past or present civilisations. Reasons are given for the significance of this process having been overlooked until now. This mechanism represents a supplementary - natural - contribution to climate change in the present epoch and may even be the dominant fundamental cause of global <span class="hlt">warming</span>, although anthropogenic effects surely play a role too.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23504800','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23504800"><span id="translatedtitle"><span class="hlt">Warming</span> and drought reduce temperature sensitivity of nitrogen transformations.</span></a></p> <p><a target="_blank" href="htt