Science.gov

Sample records for adjacent open sea

  1. Bioavailability of sinking organic matter in the Blanes canyon and the adjacent open slope (NW Mediterranean Sea)

    NASA Astrophysics Data System (ADS)

    Lopez-Fernandez, P.; Bianchelli, S.; Pusceddu, A.; Calafat, A.; Sanchez-Vidal, A.; Danovaro, R.

    2012-12-01

    Submarine canyons are sites of intense energy and material exchange between the shelf and the deep adjacent basins. To test the hypothesis that active submarine canyons represent preferential conduits of available food for the deep-sea benthos, two mooring lines were deployed at 1200 m depth from November 2008 to November 2009 inside the Blanes canyon and on the adjacent open slope (Catalan Margin, NW Mediterranean Sea). We investigated the fluxes, biochemical composition and food quality of sinking organic carbon (OC). OC fluxes in the canyon and the open slope varied among sampling periods, though not consistently in the two sites. In particular, while in the open slope the highest OC fluxes were observed in August 2009, in the canyon the highest OC fluxes occurred in April-May 2009. For almost the entire study period, the OC fluxes in the canyon were significantly higher than those in the open slope, whereas OC contents of sinking particles collected in the open slope were consistently higher than those in the canyon. This result confirms that submarine canyons are effective conveyors of OC to the deep sea, particles transferred are predominantly of inorganic origin, significantly higher than that reaching the open slope at a similar water depth. Using multivariate statistical tests, two major clusters of sampling periods were identified: one in the canyon that grouped trap samples collected in December 2008, concurrently with the occurrence of a major storm at the sea surface, and associated with increased fluxes of nutritionally available particles from the upper shelf. Another cluster grouped samples from both the canyon and the open slope collected in March 2009, concurrently with the occurrence of the seasonal phytoplankton bloom at the sea surface, and associated with increased fluxes of total phytopigments. Our results confirm the key ecological role of submarine canyons for the functioning of deep-sea ecosystems, and highlight the importance of canyons

  2. Bioavailability of sinking organic matter in the Blanes canyon and the adjacent open slope (NW Mediterranean Sea)

    NASA Astrophysics Data System (ADS)

    Lopez-Fernandez, P.; Bianchelli, S.; Pusceddu, A.; Calafat, A.; Sanchez-Vidal, A.; Danovaro, R.

    2013-05-01

    Submarine canyons are sites of intense energy and material exchange between the shelf and the deep adjacent basins. To test the hypothesis that active submarine canyons represent preferential conduits of available food for the deep-sea benthos, two mooring lines were deployed at 1200 m depth from November 2008 to November 2009 inside the Blanes canyon and on the adjacent open slope (Catalan Margin, NW Mediterranean Sea). We investigated the fluxes, biochemical composition and food quality of sinking organic carbon (OC). OC fluxes in the canyon and the open slope varied among sampling periods, though not consistently in the two sites. In particular, while in the open slope the highest OC fluxes were observed in August 2009, in the canyon the highest OC fluxes occurred in April-May 2009. For almost the entire study period, the OC fluxes in the canyon were significantly higher than those in the open slope, whereas OC contents of sinking particles collected in the open slope were consistently higher than those in the canyon. This result confirms that submarine canyons are effective conveyors of OC to the deep sea. Particles transferred to the deep sea floor through the canyons are predominantly of inorganic origin, significantly higher than that reaching the open slope at a similar water depth. Using multivariate statistical tests, two major clusters of sampling periods were identified: one in the canyon that grouped trap samples collected in December 2008, concurrently with the occurrence of a major storm at the sea surface, and associated with increased fluxes of nutritionally available particles from the upper shelf. Another cluster grouped samples from both the canyon and the open slope collected in March 2009, concurrently with the occurrence of the seasonal phytoplankton bloom at the sea surface, and associated with increased fluxes of total phytopigments. Our results confirm the key ecological role of submarine canyons for the functioning of deep-sea ecosystems

  3. Benthic meiofaunal composition and community structure in the Sethukuda mangrove area and adjacent open sea, East coast of India

    NASA Astrophysics Data System (ADS)

    Thilagavathi, Balasubramanaian; Das, Bandana; Saravanakumar, Ayyappan; Raja, Kuzhanthaivel

    2011-06-01

    The ecological aspects of meiofaunal communities in the Muthupettai mangrove forest, East coast of India, has not been investigated in the last two decades. Surface water temperature ranged from 23.5 °C to 31.8 °C. Salinity varied from 24 to 34 ppt, while water pH fluctuated from 7.4 to 8.3. Dissolved oxygen concentration ranged from 3.86 to 5.33 mg/l. Meiofauna analysis in this study identified a total of 106 species from the mangrove and adjacent open sea area of Sethukuda. Among these, 56 species of foraminiferans, 20 species of nematodes, 7 species of harpacticoid copepods, 4 species of ostrocodes, and 2 species of rotifers were identified. Furthermore, a single species was identified from the following groups: ciliophora, cnidaria, gnathostomulida, insecta, propulida, bryozoa and polychaete larvae. Meiofaunal density varied between 12029 to 23493 individuals 10 cm/m2. The diversity index ranged from 3.515 to 3.680, species richness index varied from 6.384 to 8.497, and evenness index varied from 0.839 to 0876 in the mangrove area and adjacent open sea.

  4. Metazoan meiofauna in deep-sea canyons and adjacent open slopes: A large-scale comparison with focus on the rare taxa

    NASA Astrophysics Data System (ADS)

    Bianchelli, S.; Gambi, C.; Zeppilli, D.; Danovaro, R.

    2010-03-01

    Metazoan meiofaunal abundance, total biomass, nematode size and the richness of taxa were investigated along bathymetric gradients (from the shelf break down to ca. 5000-m depth) in six submarine canyons and on five adjacent open slopes of three deep-sea regions. The investigated areas were distributed along >2500 km, on the Portuguese to the Catalan and South Adriatic margins. The Portuguese and Catalan margins displayed the highest abundances, biomass and richness of taxa, while the lowest values were observed in the Central Mediterranean Sea. The comparison between canyons and the nearby open slopes showed the lack of significant differences in terms of meiofaunal abundance and biomass at any sampling depth. In most canyons and on most slopes, meiofaunal variables did not display consistent bathymetric patterns. Conversely, we found that the different topographic features were apparently responsible for significant differences in the abundance and distribution of the rare meiofaunal taxa (i.e. taxa accounting for <1% of total meiofaunal abundance). Several taxa belonging to the temporary meiofauna, such as larvae/juveniles of Priapulida, Holothuroidea, Ascidiacea and Cnidaria, were encountered exclusively on open slopes, while others (including the Tanaidacea and Echinodea larvae) were found exclusively in canyons sediments. Results reported here indicate that, at large spatial scales, differences in deep-sea meiofaunal abundance and biomass are not only controlled by the available food sources, but also by the region or habitat specific topographic features, which apparently play a key role in the distribution of rare benthic taxa.

  5. Seismicity in Azerbaijan and Adjacent Caspian Sea

    SciTech Connect

    Panahi, Behrouz M.

    2006-03-23

    So far no general view on the geodynamic evolution of the Black Sea to the Caspian Sea region is elaborated. This is associated with the geological and structural complexities of the region revealed by geophysical, geochemical, petrologic, structural, and other studies. A clash of opinions on geodynamic conditions of the Caucasus region, sometimes mutually exclusive, can be explained by a simplified interpretation of the seismic data. In this paper I analyze available data on earthquake occurrences in Azerbaijan and the adjacent Caspian Sea region. The results of the analysis of macroseismic and instrumental data, seismic regime, and earthquake reoccurrence indicate that a level of seismicity in the region is moderate, and seismic event are concentrated in the shallow part of the lithosphere. Seismicity is mostly intra-plate, and spatial distribution of earthquake epicenters does not correlate with the plate boundaries.

  6. Macrobenthos of Yenisei Bay and the adjacent Kara Sea shelf

    NASA Astrophysics Data System (ADS)

    Galkin, S. V.; Vedenin, A. A.

    2015-07-01

    Trawl samples were collected in the northern region of Yenisei Bay and adjacent parts of the Kara Sea shelf. A total of eight stations were taken. We found more than 200 species of benthic organisms. A consecutive replacement of benthic communities is observed when going to the north from the Ob and Yenisei estuaries to the open parts of the sea. We could distinguish four different species complexes in the investigated area: a brackish-water complex where Saduria entomon is dominant; an intermediate complex where S. sibirica, S. sabini and Portlandia aestuariorum are dominant; a transitional complex with P. arctica as a dominant species and with a small amount of Ophiocten sericeum; a marine complex where O. sericeum is dominant. When salinity increased, some brackish-water species were replaced by related euryhaline species. One such example was the replacement of brackish-water Saduria entomon isopods by two euryhaline species: S. sibirica and S. sabini. The consecutive replacement of benthic communities showed a break near Sverdrup Island. In this area the marine complex was replaced by a transitional complex with P. arctica.

  7. Pelagic ciliate communities within the Amundsen Sea polynya and adjacent sea ice zone, Antarctica

    NASA Astrophysics Data System (ADS)

    Jiang, Yong; Liu, Qian; Yang, Eun Jin; Wang, Min; Kim, Tae Wan; Cho, Kyoung-Ho; Lee, SangHoon

    2016-01-01

    Polynyas, areas of open water surrounded by sea ice, are sites of intense primary production and ecological hotspots in the Antarctic Ocean. This study determined the spatial variation in communities of pelagic ciliates in an Amundsen Sea polynya (ASP) and adjacent sea ice zones (SIZ) during austral summer from February to March 2012, and the results were compared with biotic and abiotic environmental factors. The species number, abundance and biomass were higher in the ASP than SIZ. Canonical analysis indicated that the communities in the ASP were distinct from those under the sea ice. The pelagic ciliate community structure was closely correlated with environmental variability. Several primary environmental variables, both alone and in combination, were found to affect community spatial patterns. The ciliate biomasses in the ASP and SIZ areas were both significantly correlated with total and nano-Chl a. This analysis of the ciliated microzooplankton communities associated with high primary production provides new insights into the roles of ciliates in biogeochemical cycles in high-latitude polynyas. Additionally, our findings provide detailed data on the composition, distribution, and structure of polynya ciliate communities in the Amundsen Sea.

  8. Are deep-sea organisms dwelling within a submarine canyon more at risk from anthropogenic contamination than those from the adjacent open slope? A case study of Blanes canyon (NW Mediterranean)

    NASA Astrophysics Data System (ADS)

    Koenig, Samuel; Fernández, Pilar; Company, Joan B.; Huertas, David; Solé, Montserrat

    2013-11-01

    Due to their geomorphological structure and proximity to the coastline, submarine canyons may act as natural conduit routes for anthropogenic contaminants that are transported from surface waters to the deep-sea. Organisms dwelling in these canyon environments might thus be at risk of experiencing adverse health effects due to higher pollution exposure. To address this question, chemical and biochemical analyses were conducted on two of the most abundant deep-sea fish species in the study area, namely Alepocephalus rostratus and Lepidion lepidion, and the most abundant deep-sea commercial decapod crustacean Aristeus antennatus sampled inside Blanes canyon (BC) and on the adjacent open slope (OS). Persistent organic pollutants (POPs) levels, including polychlorinated biphenyl (PCB), dichlorodiphenyltrichloroethane (DDT) and derivatives, hexachlorocyclohexanes (HCHs) and hexachlorobenzene (HCB) were determined in muscle tissue of selected samples from 900 m and 1500 m depth. Potential effects resulting from contaminant exposure were determined using hepatic biomarkers such as ethoxyresorufin-O-deethylase (EROD), pentoxyresorufin-O-deethylase (PROD), catalase (CAT), carboxylesterase (CbE), glutathione-S-transferase (GST), total glutathione peroxidase (GPX), glutathione reductase (GR) and superoxide-dismutase (SOD) enzyme activities and lipid peroxidation levels (LP). L. lepidion and A. antennatus tissues exhibited higher POP levels inside BC compared to the OS at 900 m depth. These findings were consistent with biomarker data (i.e. enzymatic response to presence of contaminant agents). Elevated xenobiotic-metabolizing (EROD and PROD) and antioxidant enzymes (CAT and GPX) indicated higher contaminant exposure in both species caught within BC. No difference in POP accumulation between sites was observed in L. lepidion at 1500 m depth, nor in biomarker data, suggesting that the pollution gradient was less pronounced at greater depths. This trend was further corroborated

  9. Correlation of sea level falls interpreted from atoll stratigraphy with turbidites in adjacent basins

    SciTech Connect

    Lincoln, J.M. )

    1990-05-01

    Past sea levels can be derived from any atoll subsurface sediments deposited at or near sea level by determining the ages of deposition and correcting the present depths to the sediments for subsidence of the underlying edifice since the times of deposition. A sea level curve constructed by this method consists of discontinuous segments, each corresponding to a period of rising relative sea level and deposition of a discrete sedimentary package. Discontinuities in the sea level curve derived by this method correspond to relative sea level falls and stratigraphic hiatuses in the atoll subsurface. During intervals of relative sea level fall an atoll emerges to become a high limestone island. Sea level may fluctuate several times during a period of atoll emergence to become a high limestone island. Sea level may fluctuate several times during a period of atoll emergence without depositing sediments on top of the atoll. Furthermore, subaerial erosion may remove a substantial part of the depositional record of previous sea level fluctuations. For these reasons the authors must look to the adjacent basins to complement the incomplete record of sea level change recorded beneath atolls. During lowstands of sea level, faunas originally deposited near sea level on an atoll may be eroded and redeposited as turbidites in deep adjacent basins. Three such turbidites penetrated during deep-sea drilling at Sites 462 and 315 in the central Pacific correlate well with a late Tertiary sea level curve based on biostratigraphic ages and {sup 87}Sr/{sup 86}Sr chronostratigraphy for core from Enewetak Atoll in the northern Marshall Islands. Further drilling of the archipelagic aprons adjacent to atolls will improve the sea level history that may be inferred from atoll stratigraphy.

  10. Mercury Export from Mainland China to Adjacent Seas and Its Influence on the Marine Mercury Balance.

    PubMed

    Liu, Maodian; Chen, Long; Wang, Xuejun; Zhang, Wei; Tong, Yindong; Ou, Langbo; Xie, Han; Shen, Huizhong; Ye, Xuejie; Deng, Chunyan; Wang, Huanhuan

    2016-06-21

    Exports from mainland China are a significant source of mercury (Hg) in the adjacent seas (Bohai Sea, Yellow Sea, East China Sea, and South China Sea) near China. A total of 240 ± 23 Mg was contributed in 2012 (30% from natural sources and 70% from anthropogenic sources), including Hg from rivers, industrial wastewater, domestic sewage, groundwater, nonpoint sources, and coastal erosion. Among the various sources, the Hg from rivers amounts to 160 ± 21 Mg and plays a dominant role. The Hg that is exported from mainland China increased from 1984 to 2013; the contributions from rivers, industrial wastewater, domestic sewage and groundwater increased, and the contributions from nonpoint sources and coastal erosion remained stable. A box model is constructed to simulate the mass balance of Hg in these seas and quantify the sources, sinks and Hg biogeochemical cycle in the seas. In total, 160 Mg of Hg was transported to the Pacific Ocean and other oceans from these seas through oceanic currents in 2012, which could have negative impacts on the marine ecosystem. A prediction of the changes in Hg exportation through 2030 shows that the impacts of terrestrial export might worsen without effective pollution reduction measures and that the Hg load in these seas will increase, especially in the seawater of the Bohai Sea, Yellow Sea, and East China Sea and in the sea margin sediments of the Bohai Sea and East China Sea. PMID:27243109

  11. A regional ocean reanalysis system for coastal waters of China and adjacent seas

    NASA Astrophysics Data System (ADS)

    Han, Guijun; Li, Wei; Zhang, Xuefeng; Li, Dong; He, Zhongjie; Wang, Xidong; Wu, Xinrong; Yu, Ting; Ma, Jirui

    2011-05-01

    A regional ocean reanalysis system for the coastal waters of China and adjacent seas has been developed by the National Marine Data and Information Service (NMDIS). It produces a dataset package called CORA (China ocean reanalysis). The regional ocean model used is based on the Princeton Ocean Model with a generalized coordinate system (POMgcs). The model is parallelized by NMDIS with the addition of the wave breaking and tidal mixing processes into model parameterizations. Data assimilation is a sequential three-dimensional variational (3D-Var) scheme implemented within a multigrid framework. Observations include satellite remote sensing sea surface temperature (SST), altimetry sea level anomaly (SLA), and temperature/salinity profiles. The reanalysis fields of sea surface height, temperature, salinity, and currents begin with January 1986 and are currently updated every year. Error statistics and error distributions of temperature, salinity and currents are presented as a primary evaluation of the reanalysis fields using sea level data from tidal gauges, temperature profiles, as well as the trajectories of Argo floats. Some case studies offer the opportunity to verify the evolution of certain local circulations. These evaluations show that the reanalysis data produced provide a good representation of the ocean processes and phenomena in the coastal waters of China and adjacent seas.

  12. A new version of regional ocean reanalysis for coastal waters of China and adjacent seas

    NASA Astrophysics Data System (ADS)

    Han, Guijun; Li, Wei; Zhang, Xuefeng; Wang, Xidong; Wu, Xinrong; Fu, Hongli; Zhang, Xiaoshuang; Zhang, Lianxin; Li, Dong

    2013-07-01

    A new regional ocean reanalysis over multiple decades (1958-2008) for the coastal waters of China and adjacent seas has been completed by the National Marine Data and Information Service (NMDIS) under the CORA (China Ocean ReAnalysis) project. Evaluations were performed on three aspects: (1) the improvement of general reanalysis quality; (2) eddy structures; and (3) decadal variability of sea surface height anomalies (SSHAs). Results showed that the quality of the new reanalysis has been enhanced beyond ˜40% (39% for temperature, 44% for salinity) in terms of the reduction of root mean squared errors (RMSEs) for which the reanalysis values were compared to observed values in the observational space. Compared to the trial version released to public in 2009, the new reanalysis is able to reproduce more detailed eddy structures as seen in satellite and in situ observations. EOF analysis of the reanalysis SSHAs showed that the new reanalysis reconstructs the leading modes of SSHAs much better than the old version. These evaluations suggest that the new CORA regional reanalysis represents a much more useful dataset for the community of the coastal waters of China and adjacent seas.

  13. Standing stock of deep-sea metazoan meiofauna in the Sulu Sea and adjacent areas

    NASA Astrophysics Data System (ADS)

    Shimanaga, Motohiro; Nomaki, Hidetaka; Suetsugu, Kishiko; Murayama, Masafumi; Kitazato, Hiroshi

    2007-01-01

    Standing stocks of deep-sea metazoan meiofauna were investigated in the Sulu Sea, one of the most isolated marginal basins with comparably warm bottom-water temperatures (˜10 °C) at depths below 1000 m. A decline in the abundance and biomass of organisms with increasing water depth occurred in the basin, but the abundances at bathyal and abyssal sites in the Sulu Basin appeared to be lower than standard values worldwide when adjusted for water depth. There is no significant correlation between meiofaunal abundance and the concentration of chloroplastic pigment equivalents (CPE) in the sediment, an indicator of the amount of organic matter derived from primary production. The ratios of meiofaunal abundance to CPE concentration at the sampling sites were as small as those observed at comparable depths in the Red Sea. These suggest that the quantity of "food" is not a primary factor limiting the density of organisms in the basin. It is hypothesized that a higher respiratory activity of benthos caused by warm bottom water and a lower food quality could be important factors regulating the metazoan meiofaunal standing stocks in the Sulu Sea.

  14. Trends in trace organic and metal concentrations in the Pechora and Kara Seas and adjacent rivers

    SciTech Connect

    Brooks, J.M.; Champ, M.A.; Wade, T.L.; Kennicutt, M.C. II; Chambers, L.; Davis, T.

    1995-12-31

    Trace organic (pesticides, PCBs, PAHs and dioxin/furan) and trace metal concentrations have been measured in surficial sediment and tissue (i.e., clam, fish liver and flesh) samples from the Pechora and Kara Seas and their adjacent rivers -- Pechora, Ob and Yenisey Rivers. Total PAH, PCB and total DDT and chlordane concentrations ranged in surficial sediments from n.d. to 810 ppb, n.d.--8.7 ppb, n.d.--1.2 ppb, and n.d.--1.2 ppb, respectively, in a suite of 40 samples from the Kara Sea and its adjacent rivers. The highest concentrations of many of the trace organic and metal contaminants were found in the lower part of the Yenisey River below the salt wedge. Some trace metals (As for example) were elevated in the Pechora River dispositional plume region. Dioxin ranged from 1.36 to 413 ppt in a subset of 20 sediment samples. Higher trace organic contaminant concentrations compared to sediments were found in tissue samples from the region, especially fish liver samples. Concentrations as high as 1,114 ppb total PAHs, 89 ppb chlordane, 1,011 ppb for total DDT and 663 ppb PCBs were found in some fish liver samples. Dioxin concentrations in tissue samples ranged from 11.7 to 61 ppt. Concentrations of many trace organic and metal contaminants in these Russian marginal seas are influenced by inputs from these large Arctic rivers. Many organic contaminant concentrations in sediments are low, however detecting these compounds in tissue show they are bioavailable.

  15. Basement structures of East and South China Seas and adjacent regions from gravity inversion

    NASA Astrophysics Data System (ADS)

    Guan, Dongliang; Ke, Xiaoping; Wang, Yong

    2016-03-01

    The satellite-derived gravity gives us an opportunity to investigate the basement structures of the East and South China Seas since the satellite gravimetry could provide large scale gravity data with high resolution of 1 arc-min by 1 arc-min. We isolate the residual gravity anomaly corresponding to the basement by subtracting the gravity anomalies of sediments and Moho undulations from satellite-derived free-air gravity anomalies. Two methods, namely gravity inversion method and convolution method based on flexure isostasy model, are used to calculate the Moho undulations in order to guarantee the accuracy of the Moho undulations since it occupies large percentages of the gravity anomalies. We invert the isolated gravity anomaly for the basement depths of East and South China Seas and adjacent areas with resolution of 1 arc-min by 1 arc-min. The basement depths of East and South China Seas range from 0.5 km to 12 km and the Moho depths vary between 6 km and 32 km. The basement topography reveals many tectonic depressions and two spreading axes concealed by the sediments, which are unseen in the bathymetry. The two spreading axes correspond to the spreading ridges derived from magnetic anomaly and the SW-NE oriented spreading axis extends SW much farther than that identified from magnetic anomaly, almost reaching to the Nam Con Son Basin. We also find that the faults constrain the distributions of basement depressions since the faults usually lie along the places where large changes of basement depth take place. Reversely, the basement map could be used to identify the unknown faults. Besides, according to the four profiles in the East and South China Seas, the mirror-image relation was found between the basement topography and the underlying Moho undulations that when the basement depth increases or decreases, the corresponding Moho depth decreases or increases.

  16. On the tectonic problems of the southern East China Sea and adjacent regions: Evidence from gravity and magnetic data

    NASA Astrophysics Data System (ADS)

    Shang, Luning; Zhang, Xunhua; Han, Bo; Du, Runlin

    2016-02-01

    In this paper, two sets of gravity and magnetic data were used to study the tectonics of the southern East China Sea and Ryukyu trench-arc system: one data set was from the `Geological-geophysical map series of China Seas and adjacent areas' database and the other was newly collected by R/V Kexue III in 2011. Magnetic and gravity data were reorganized and processed using the software MMDP, MGDP and RGIS. In addition to the description of the anomaly patterns in different areas, deep and shallow structure studies were performed by using several kinds of calculation, including a spectrum analysis, upward-continuation of the Bouguer anomaly and horizontal derivatives of the total-field magnetic anomaly. The depth of the Moho and magnetic basement were calculated. Based on the above work, several controversial tectonic problems were discussed. Compared to the shelf area and Ryukyu Arc, the Okinawa Trough has an obviously thinned crust, with the thinnest area having thickness less than 14 km in the southern part. The Taiwan-Sinzi belt, which terminates to the south by the NW-SE trending Miyako fault belt, contains the relic volcanic arc formed by the splitting of the paleo Ryukyu volcanic arc as a result of the opening of the Okinawa Trough. As an important tectonic boundary, the strike-slip type Miyako fault belt extends northwestward into the shelf area and consists of several discontinuous segments. A forearc terrace composed of an exotic terrane collided with the Ryukyu Arc following the subduction of the Philippine Sea Plate. Mesozoic strata of varying thicknesses exist beneath the Cenozoic strata in the shelf basin and significantly influence the magnetic pattern of this area. The gravity and magnetic data support the existence of a Great East China Sea, which suggests that the entire southern East China Sea shelf area was a basin in the Mesozoic without alternatively arranged uplifts and depressions, and might have extended southwestward and connected with the

  17. Ocean tides in the northern North Atlantic and adjacent seas from ERS 1 altimetry

    NASA Astrophysics Data System (ADS)

    Andersen, Ole Baltazar

    1994-11-01

    Twenty months of ERS 1 35-day repeat altimeter data containing 18 repeat cycles have been used to estimate the major diurnal and semidiurnal ocean tide signals in the northern parts of the North Atlantic and adjacent seas. ERS 1 provides valuable information when investigating ocean tides, owing to the repeated dense spatial sampling. However, several tidal constituents are extremely difficult to resolve using conventional harmonic analysis with the chosen sun syncronous orbit. Instead, temporal analysis at each crossover location is applied using a modified form of the orthotide formulation, which simultaneously solves for the diurnal and semidiurnal species as well as for the annual signal. The use of the response formalism ensures that the sun syncronous component S2 can be resolved, although this component is "frozen" in the orbit. Maps of the M2, S2 and K1 tidal amplitudes and phases in 0.5°×0.5° grids are presented and are seen to compare favorably with measurements at 68 pelagic tide gauges provided by the International Association for Physical Sciences of the Ocean. The major tidal constituents of the ERS 1 derived model are also in close agreement with the improved Flather (1981) ocean tide model for the northwest European continental shelf area, as well as a numerical model for the Arctic and Nordic Seas by Gjevik and Straume (1989).

  18. Seismic imaging of mantle transition zone discontinuities beneath the northern Red Sea and adjacent areas

    NASA Astrophysics Data System (ADS)

    Mohamed, A. A.; Gao, S. S.; Elsheikh, A. A.; Liu, K. H.; Yu, Y.; Fat-Helbary, R. E.

    2014-11-01

    The dramatic asymmetry in terms of surface elevation, Cenozoic volcanisms and earthquake activity across the Red Sea is an enigmatic issue in global tectonics, partially due to the unavailability of broad-band seismic data on the African Plate adjacent to the Red Sea. Here, we report the first comprehensive image of the mantle transition zone (MTZ) discontinuities using data from the Egyptian National Seismic Network, and compare the resulting depths of the 410 and 660-km discontinuities with those observed on the Arabian side. Our results show that when a standard earth model is used for time-to-depth conversion, the resulting depth of the discontinuities increases systematically towards the axis of the Afro-Arabian Dome (AAD) from both the west and east. Relative to the westernmost area, the maximum depression of the 410-km discontinuity is about 30 km, and that of the 660-km discontinuity is about 45 km. The observed systematic variations can best be explained by a model involving a hydrated MTZ and an upper-mantle low-velocity zone beneath the AAD. Models invoking one or more mantle plumes originated from the MTZ or the lower-mantle beneath the study area are not consistent with the observations.

  19. Heat flow distribution and thermal structure of the Philippine Sea Plate and its adjacent areas

    NASA Astrophysics Data System (ADS)

    Wang, Q.; Chen, C.; Liang, Q.; Sun, S.

    2013-12-01

    Research on the present geothermal state is an important way to understand the lithospheric geodynamics. We studied the heat flow (HF) distribution and the geothermal structure of the Philippine Sea Plate (PSP) and its adjacent area (100°E~155°E, 5°S~45°N) surrounded by the East China Sea, South China Sea and the West Pacific Ocean, which is aimed to provide thermal constraints for the dynamic mechanism and tectonic evolution of the PSP. Based on the observed seafloor HF data of the study area with the latest release of CRUST1.0 crustal layered model, the lithospheric geotherm was calculated using 1D steady-state heat conduction equation. However, the obtained numerous geotherms derived from the extrapolation through heat conduction equation strongly depended on the accuracy of the measured HF data, which is limited, unevenly distributed and easily affected by local factors. Therefore, as a meaningful comparison, the temperature distributions at 25 km and 50 km depth inferred from the upper mantle shear wave velocities structure (S2.9EA) are inverted. The HF distribution shows relatively high values in Ryuku Trench and nearby Izu-Boning Trench, where the crust thicken and the mantle uplift obviously as typical transition zones. The Mariana Trench located in the east (southeast) part and the Philippine Trench in the southwest both are with low HF, which is also illustrated in the upper mantle gravity map after temperature correction. The Central Basin Ridge is with unquestionable high HF, being perpendicular to which the value decreasing. The calculated temperature maps (at depth of 25 km and 50 km) by the two methods both present that the temperature in PSP is higher than that in the Western Pacific Ocean and the west Philippine Basin is lower than the east one, which consists well with the crust age. The west half parts both of the Philippine Basin and Parece Vela Basin show low temperature, but high value in Ryuku Trench, Nankai Through, Shikoku Basin, Amami

  20. A benchmark-multi-disciplinary study of the interaction between the Chesapeake Bay and adjacent waters of the Virginian Sea

    NASA Technical Reports Server (NTRS)

    Hargis, W. J., Jr.

    1981-01-01

    The social and economic importance of estuaries are discussed. Major focus is on the Chesapeake Bay and its interaction with the adjacent waters of the Virginia Sea. Associated multiple use development and management problems as well as their internal physical, geological, chemical, and biological complexities are described.

  1. Structure of phytoplankton communities in the Yenisei estuary and over the adjacent Kara Sea shelf

    NASA Astrophysics Data System (ADS)

    Sukhanova, I. N.; Flint, M. V.; Sergeeva, V. M.; Druzhkova, E. I.; Nedospasov, A. A.

    2015-11-01

    Material was collected in the Yenisei estuary and over the adjacent Kara Sea shelf at a quasimeridional transect from 71°49'70″ to 75°59'93″ N in September 2011. The structural characteristics of the phytoplankton community were determined by latitudinal zonality of environmental conditions. Two well-distinguished phytocenoses—freshwater and marine—were found in this region. Phytoplankton in the freshwater part of the estuary was composed solely of the freshwater algae species and was distinguished by the highest numbers (up to 2 × 106 cell/L) and biomass (up to 1.4 mg/L). The marine phytocenoses over the Yenisei shoal was composed of marine neritic species; the abundance and biomass of phytoplankton in this area were significantly lower (0.2 × 106 cell/L and 0.4 mg/L, respectively). The area of intensive interaction of riverine and marine waters—the estuarine frontal zone, with ~130 km latitudinal extension (from 72° to 74° N)—was characterized by a sharp halocline, which separated the desalinated upper layer from the underlying marine water. Freshwater algal species predominated above the halocline, whereas marine species predominated below. The lower border of the euphotic layer was located 8 to 15 m below the halocline. The niche between the halocline and the lower border of the euphotic layer was characterized by high nutrient concentrations, which together with sufficient illumination determined the intensive development of phytoplankton and high values of primary production.

  2. Changes in Climate over the South China Sea and Adjacent Regions: Response to and Feedback on Global Climate Change

    NASA Astrophysics Data System (ADS)

    Yang, Song

    2016-04-01

    El Niño-Southern Oscillation and the Asian monsoon have experienced significant long-term changes in the past decades. These changes, together with other factors, have in turn led to large climate change signals over the South China Sea and adjacent regions including Southeast Asia, the western Pacific, and the tropical Indian Ocean. An attribution analysis of the feedback processes of these signals indicate the predominant importance of water vapor and cloud radiative feedbacks. Experiments with multiple earth system models also show that these regional climate change signals exert significant influences on global climate. The increases in atmospheric heating over Southeast Asia and sea surface temperature in the adjacent oceans in the past decades have weakened the Indian and African monsoons, led to a drying effect over East Asia, and generated wave-train patterns in both the northern and southern hemispheres, explaining several prominent climate features in and outside Southeast Asia.

  3. Open Ocean Internal Waves, South China Sea

    NASA Technical Reports Server (NTRS)

    1989-01-01

    These open ocean internal waves were seen in the south China Sea (19.5N, 114.5E). These sets of internal waves most likely coincide with tidal periods about 12 hours apart. The wave length (distance from crest to crest) varies between 1.5 and 5.0 miles and the crest lengths stretch across and beyond this photo for over 75 miles. At lower right, the surface waves are moving at a 30% angle to the internal waves, with parallel low level clouds.

  4. The Surf Zone Ichthyoplankton Adjacent to an Intermittently Open Estuary, with Evidence of Recruitment during Marine Overwash Events

    NASA Astrophysics Data System (ADS)

    Cowley, P. D.; Whitfield, A. K.; Bell, K. N. I.

    2001-03-01

    The composition, structure and seasonality of ichthyoplankton in the surf zone adjacent to the mouth of the intermittently open East Kleinemonde Estuary (33°32'S, 27°03'E) were investigated over a period of 2 years. Altogether 451 fishes, representing at least 21 taxa from 14 families, were collected. The assemblage was dominated by postflexion larvae of euryhaline marine species that are dependent on estuaries as nursery areas. The sparid Rhabdosargus holubi was the most abundant taxon and constituted more than 77% of the total catch. A distinct modal size class was identified for R. holubi , while the mean individual size of this and other abundant taxa was comparable to the observed recruitment size range reported from a wide variety of estuarine nursery habitats in southern Africa. Periodic regression analyses revealed significant peaks in abundance of larval R. holubi during late winter (August), at down and dusk, at new and full moon (spring tides), and on the flood stage of the tidal cycle. Evidence for estuarine immigration during marine overwash events (surging rough seas that enter the estuary) is provided by (1) the stranding of postflexion larvae in the region of the closed estuary mouth following these events, and (2) back extrapolation from length modes within the estuary to coincide with such an event. The advantages and disadvantages of such a recruitment strategy are discussed.

  5. Climatology of the oceanography in the northern South China Sea Shelf-sea (NoSoCS) and adjacent waters: Observations from satellite remote sensing

    NASA Astrophysics Data System (ADS)

    Pan, X.; Wong, G. T.; Tai, J.; Ho, T.

    2013-12-01

    By using the observations from multiple satellite sensors, the climatology of the oceanography, including the surface wind vector, sea surface temperature (SST), surface chlorophyll a concentration (Chl_a), and vertically integrated net primary production (PPeu), in the northern South China Sea Shelf-sea (NoSoCS) and adjacent waters is evaluated. Regional and sub-regional mechanisms in driving the coastal processes, which influence the spatial and temporal distributional patterns in water component, are assessed. Seasonal vertical convective mixing by wind and surface heating/cooling is the primary force in driving the annual changes in SST and Chl_a in the open South China Sea (SCS), in which highly negative correlation coefficients between Chl_a and SST and moderately positive correlation coefficients between Chl_a and wind speed are found. Together, the seasonal variations in SST and wind speed account for about 80% of the seasonal variation in Chl_a. In the NoSoCS as a whole, however, the contribution is reduced to about 40%, primarily due to the effect of the Pearl River plume. A tongue of water extending eastward from the mouth of the River into the middle shelf with positive correlation coefficients between Chl_a and SST and around zero or slightly negative correlation coefficients between Chl_a and wind is the most striking feature in the NoSoCS. The westward and eastward propagations of the Pearl River plume are both very small during the northeast monsoonal season, driven primarily by the Coriolis effect. The abrupt increase in the areal coverage of the River plume, which is much more pronounced in the eastward propagation, between June and August can be attributed to the prevailing southwest monsoon as well as the annual peak of the river flow. Coastal upwelling is another sub-regional phenomenon in the NoSoCS. The upwelling at the shelf edge off the Taiwan Bank may be characterized by its elevated Chl_a. Its areal coverage and average Chl_a do not vary

  6. Metal elements in the bottom sediments of the Changjiang Estuary and its adjacent continental shelf of the East China Sea.

    PubMed

    Cao, Lu; Hong, Gi Hoon; Liu, Sumei

    2015-06-15

    The metal elements (Al, Fe, Mn, Cr, Co, Ni, Cu, Zn, As, Pb and Ca) in the bottom sediment of the Changjiang Estuary and its adjacent continental shelf of the East China Sea were studied to map their spatial distribution and to assess their potential risk to the marine biota. These metal concentrations except Ca were generally higher in the inner shelf and northeastern part, and were found to decrease from the coast to the offshore of the Changjiang Estuary. Sedimentary Ca was most abundant in the outer shelf sediments and decreased in inner shelf. Arsenic (As) appeared to be contaminated due to economic development from 1980s in the inner shelf overall, but the potential ecological risk from the selected metals was low in the coastal sea off the Changjiang. PMID:25869200

  7. Historical change and future scenarios of sea level rise in Macau and adjacent waters

    NASA Astrophysics Data System (ADS)

    Wang, Lin; Huang, Gang; Zhou, Wen; Chen, Wen

    2016-04-01

    Against a background of climate change, Macau is very exposed to sea level rise (SLR) because of its low elevation, small size, and ongoing land reclamation. Therefore, we evaluate sea level changes in Macau, both historical and, especially, possible future scenarios, aiming to provide knowledge and a framework to help accommodate and protect against future SLR. Sea level in Macau is now rising at an accelerated rate: 1.35 mm yr-1 over 1925-2010 and jumping to 4.2 mm yr-1 over 1970-2010, which outpaces the rise in global mean sea level. In addition, vertical land movement in Macau contributes little to local sea level change. In the future, the rate of SLR in Macau will be about 20% higher than the global average, as a consequence of a greater local warming tendency and strengthened northward winds. Specifically, the sea level is projected to rise 8-12, 22-51 and 35-118 cm by 2020, 2060 and 2100, respectively, depending on the emissions scenario and climate sensitivity. Under the +8.5 W m-2 Representative Concentration Pathway (RCP8.5) scenario the increase in sea level by 2100 will reach 65-118 cm—double that under RCP2.6. Moreover, the SLR will accelerate under RCP6.0 and RCP8.5, while remaining at a moderate and steady rate under RCP4.5 and RCP2.6. The key source of uncertainty stems from the emissions scenario and climate sensitivity, among which the discrepancies in SLR are small during the first half of the 21st century but begin to diverge thereafter.

  8. Large-Scale Distribution and Activity of Prokaryotes in Deep-Sea Surface Sediments of the Mediterranean Sea and the Adjacent Atlantic Ocean

    PubMed Central

    Giovannelli, Donato; Molari, Massimiliano; d’Errico, Giuseppe; Baldrighi, Elisa; Pala, Claudia; Manini, Elena

    2013-01-01

    The deep-sea represents a substantial portion of the biosphere and has a major influence on carbon cycling and global biogeochemistry. Benthic deep-sea prokaryotes have crucial roles in this ecosystem, with their recycling of organic matter from the photic zone. Despite this, little is known about the large-scale distribution of prokaryotes in the surface deep-sea sediments. To assess the influence of environmental and trophic variables on the large-scale distribution of prokaryotes, we investigated the prokaryotic assemblage composition (Bacteria to Archaea and Euryarchaeota to Crenarchaeota ratio) and activity in the surface deep-sea sediments of the Mediterranean Sea and the adjacent North Atlantic Ocean. Prokaryotic abundance and biomass did not vary significantly across the Mediterranean Sea; however, there were depth-related trends in all areas. The abundance of prokaryotes was positively correlated with the sedimentary concentration of protein, an indicator of the quality and bioavailability of organic matter. Moving eastwards, the Bacteria contribution to the total prokaryotes decreased, which appears to be linked to the more oligotrophic conditions of the Eastern Mediterranean basins. Despite the increased importance of Archaea, the contributions of Crenarchaeota Marine Group I to the total pool was relatively constant across the investigated stations, with the exception of Matapan-Vavilov Deep, in which Euryarchaeota Marine Group II dominated. Overall, our data suggest that deeper areas of the Mediterranean Sea share more similar communities with each other than with shallower sites. Freshness and quality of sedimentary organic matter were identified through Generalized Additive Model analysis as the major factors for describing the variation in the prokaryotic community structure and activity in the surface deep-sea sediments. Longitude was also important in explaining the observed variability, which suggests that the overlying water masses might have a

  9. Autotrophic Microbe Metagenomes and Metabolic Pathways Differentiate Adjacent Red Sea Brine Pools

    PubMed Central

    Wang, Yong; Cao, Huiluo; Zhang, Guishan; Bougouffa, Salim; Lee, On On; Al-Suwailem, Abdulaziz; Qian, Pei-Yuan

    2013-01-01

    In the Red Sea, two neighboring deep-sea brine pools, Atlantis II and Discovery, have been studied extensively, and the results have shown that the temperature and concentrations of metal and methane in Atlantis II have increased over the past decades. Therefore, we investigated changes in the microbial community and metabolic pathways. Here, we compared the metagenomes of the two pools to each other and to those of deep-sea water samples. Archaea were generally absent in the Atlantis II metagenome; Bacteria in the metagenome were typically heterotrophic and depended on aromatic compounds and other extracellular organic carbon compounds as indicated by enrichment of the related metabolic pathways. In contrast, autotrophic Archaea capable of CO2 fixation and methane oxidation were identified in Discovery but not in Atlantis II. Our results suggest that hydrothermal conditions and metal precipitation in the Atlantis II pool have resulted in elimination of the autotrophic community and methanogens. PMID:23624511

  10. Diversity and distribution of Porifera in the bathyal and abyssal Weddell Sea and adjacent areas

    NASA Astrophysics Data System (ADS)

    Janussen, Dorte; Tendal, Ole Secher

    2007-08-01

    During the ANDEEP I-III expeditions, we obtained a rich and highly diverse sponge collection from the deep Weddell Sea. All the three Poriferan classes, Calcarea, Demospongiae and Hexactinellida, were well represented. Among this material, we have identified a total of 76 species from 47 genera and 30 families. Of these, 17 species (22%) are new to science and 37 (49%) new for the Southern Ocean. Particularly remarkable is the considerable depth of the boundary between bathyal and abyssal sponge faunas. Both Demospongiae and Hexactinellida show a strong shift in their taxonomic composition from a typical shelf assemblage to a more cosmopolitan deep-sea fauna at around 2500 m. Within the Demospongiae, the families Polymastiidae and Cladorhizidae (carnivorous sponges) are particularly abundant and very diverse. The Calcarea are recorded for the first time from the Antarctic deep sea. The type of sampling gear used, especially the epibenthic sledge, was an important factor for the successful collection of deep-sea sponges during the ANDEEP campaigns.

  11. Contrasts Between Precipitation over Mediterranean Sea and Adjacent Continental Areas Based on Decadal Scale Satellite Estimates

    NASA Technical Reports Server (NTRS)

    Smith, Eric A.

    2007-01-01

    Most knowledge concerning the last century's climatology and climate dynamics of precipitation over the Mediterranean Sea basin is based on observations taken from rain gauges surrounding the sea itself. In turn, most of the observations come from Southern Europe, with many fewer measurements taken from widely scattered sites situated over North Africa, the Middle East, and the Balkans. This aspect of research on the Mediterranean Sea basin is apparent in a recent compilation of studies presented in book form concerning climate variability of the Mediterranean region [Lionello, P., P. Malanotte-Rizzoli, and R. Boscolo (eds.), 2006: Mediterranean Climate Variability. Elsevier, Amsterdam, 9 chapters.] In light of this missing link to over-water observations, this study (in conjunction with four companion studies by Z. Haddad, A. Mugnai, T. Nakazawa, and G. Stephens) will contrast the nature of precipitation variability directly over the Mediterranean Sea to precipitation variability over the surrounding land areas based on three decades of satellite-based precipitation estimates which have stood up well to validation scrutiny. The satellite observations are drawn from the Global Precipitation Climatology Project (GPCP) dataset extending back to 1979 and the TRMM Merged Algorithm 3b42 dataset extending back to 1998. Both datasets are mostly produced from microwave measurements, excepting the period from 1979 to mid-1987 when only infrared satellite measurements were available for the GPCP estimates. The purpose of this study is to emphasize how the salient properties of precipitation variability over land and sea across a hierarchy of space and time scales, and the salient differences in these properties, might be used in guiding short-term climate models to better predictions of future climate states under different regional temperature-change scenarios.

  12. Recent seasonal hypoxia on the Western Black Sea shelf recorded in adjacent slope sediments

    NASA Astrophysics Data System (ADS)

    Roepert, Anne; Jilbert, Tom S.; Slomp, Caroline P.

    2015-04-01

    Bottom water hypoxia is a major environmental problem afflicting estuarine and marine environments across the globe (Diaz and Rosenberg, 2008). Hypoxia is often attributed to human-induced increased nutrient discharge from rivers and related eutrophication. The Western Black Sea shelf is a typical example of a system where such anthropogenic impacts are thought to have contributed to the development of seasonal hypoxia in the late 20th century. However, due to the lack of spatially and temporally consistent monitoring in the region, questions remain about the evolution, causes and consequences of the seasonal hypoxia on the Western Black Sea shelf and whether or not the ecological state has recently improved (Capet et al., 2013). In this study a resin-embedded sediment core from a location below the chemocline on the Western Black Sea slope (water depth 377 m) was analyzed for its elemental composition by means of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), recovering a continuous geochemical record at a sub-annual resolution for the last 100 years. Relative enrichments in organic carbon, Pb, Fe, S, and Mo were observed in the depth interval corresponding to the 1970s until the 1990s, suggesting an increased carbon flux to the sediments as well as an anthropogenic pollution signal. We propose that the expansion of eutrophication on the Western Black Sea shelf was responsible for the enhanced carbon flux to our study site, while the associated hypoxia enhanced the shuttling of redox-sensitive elements to locations below the chemocline. The subsequent decrease in organic carbon and metal enrichments at the core top suggests a recent rise in oxygen concentrations and improvement of the ecological state of the Western Black Sea shelf. References: Capet, A., Beckers, J.-M., Grégoire, M. (2013). "Drivers, mechanisms and long-term variability of seasonal hypoxia on the Black Sea northwestern shelf-is there any recovery after eutrophication

  13. Macrobenthos of the southern part of St. Anna trough and the adjacent Kara Sea shelf

    NASA Astrophysics Data System (ADS)

    Galkin, S. V.; Vedenin, A. A.; Minin, K. V.; Rogacheva, A. V.; Molodtsova, T. N.; Rajskiy, A. K.; Kucheruk, N. V.

    2015-07-01

    Taxonomic composition and ecological structure of benthic communities of the southern part of St. Anna Trough were investigated during the 54th and 59th cruises of RV Akademik Mstislav Keldysh. Material was collected using Sigsbee trawl at 10 stations arranged in two transects (depth range 57-554 m). It was shown that benthic communities of the western arm of the St. Anna Trough differ considerably from the communities of the eastern arm. The western arm communities develop under the influence of active near-bottom hydrodynamics in conditions of rugged topography and a coarse-grained sediment or hard substrate. The wastern arm of the trough is characterized by the predomination of the soft sediment, smooth topography, and weak currents. In the western arm of the trough the influence of the Barents Sea fauna is traced down to the edge of the internal shelf (about 150 m depth). The community of the eastern arm of the trough situated out from the direct influence of the Barents Sea waters represents a continuation of the Ophiocten sericeum community, typical for external Kara Sea shelf. With increasing depth, Ophiopleura borealis becomes the dominant species of the community. In the greatest explored depths some deep-water High-Arctic species, such as echinoids Pourtalesia jeffreysi, were observed. The major factors determining the distribution of benthic communities in the investigated area are the microrelief pattern, the sediment structure, and near-bottom hydrodynamics.

  14. Deep Structures of the Palawan and Sulu Sea and Their Implications for Opening of the South China Sea

    NASA Astrophysics Data System (ADS)

    Liu, W.; Li, C. F.; Li, J.; Fairhead, D.; Zhou, Z.

    2014-12-01

    Compared to the northern South China Sea continental margin, the deep structures and tectonic evolution of the Palawan and Sulu Sea and ambient regions are not well understood so far. However, this part of the southern continental margin and adjacent areas embed critical information on the opening of the South China Sea (SCS). We carry out geophysical investigations using regional magnetic, gravity and reflection seismic data. Analytical signal amplitudes (ASA) of magnetic anomalies are calculated to depict the boundaries of different tectonic units. Curie-point depths are estimated from magnetic anomalies using a windowed wavenumber-domain algorithm. Application of the Parker-Oldenburg algorithm to Bouguer gravity anomalies yields a 3D Moho topography. The Palawan Continental Block (PCB) is defined by quiet magnetic anomalies, low ASA, moderate depths to the top and bottom of the magnetic layer, and its northern boundary is further constrained by reflection seismic data and Moho interpretation. However, the continent-ocean transition zone between the PCB and the SCS is characterized by hyper-extended continental crust intruded with magmatic bodies. The NW Sulu Sea is interpreted as a relict oceanic slice and the geometry and position of extinct trench of the Proto South China Sea (PSCS) is further constrained. With additional age constraints from inverted Moho and Curie-point depths, we confirm that the spreading of the SE Sulu Sea started in the Early Oligocene/Late Eocene due to the subduction of the PSCS, and terminated in the Middle Miocene by the obduction of the NW Sulu Sea onto the PCB. According to the newly constrained age of SE Sulu Sea, we also estimate the approximate extent, spreading rate and subducting rate of original SE Sulu Sea.

  15. Decadal changes in climate and ecosystems in the North Atlantic Ocean and adjacent seas

    NASA Astrophysics Data System (ADS)

    Beaugrand, Grégory

    2009-04-01

    Climate change is unambiguous and its effects are clearly detected in all functional units of the Earth system. This study presents new analyses of sea-surface temperature changes and show that climate change is affecting ecosystems of the North Atlantic. Changes are seen from phytoplankton to zooplankton to fish and are modifying the dominance of species and the structure, the diversity and the functioning of marine ecosystems. Changes also range from phenological to biogeographical shifts and have involved in some regions of the Atlantic abrupt ecosystem shifts. These alterations reflect a response of pelagic ecosystems to a warmer temperature regime. Mechanisms are complex because they are nonlinear exhibiting tipping points and varying in space and time. Sensitivity of organisms to temperature changes is high, implicating that a small temperature modification can have sustained ecosystem effects. Implications of these changes for biogeochemical cycles are discussed. Two observed changes detected in the North Sea that could have opposite effects on carbon cycle are discussed. Increase in phytoplankton, as inferred from the phytoplankton colour index derived from the Continuous Plankton Recorder (CPR) survey, has been detected in the North Sea. This pattern has been accompanied by a reduction in the abundance of the herbivorous species Calanus finmarchicus. This might have reduced the grazing pressure and increase diatomaceous 'fluff', therefore carbon export in the North Sea. Therefore, it could be argued that the biological carbon pump might increase in this region with sea warming. In the meantime, however, the mean size of organisms (calanoid copepods) has dropped. Such changes have implications for the turnover time of biogenic carbon in plankton organisms and the mean residence time of particulate carbon they produce. The system characterising the warmer period is more based on recycling and less on export. The increase in the minimum turnover time

  16. Spatiotemporal distribution of bacterioplankton and bacteriobenthos in the Amur Liman and adjacent sea areas

    NASA Astrophysics Data System (ADS)

    Karetnikova, E. A.; Garetova, L. A.

    2015-09-01

    Data on the abundance and the ecological-trophic structure of bacterioplankton and bacteriobenthos communities in the Amur Liman and adjacent waters collected in June 2007 have been compared to the relevant data of 2006. Interyear changes of bacterioplankton abundance have been found to depend on the intensity of the Amur River runoff. Correlation analysis has revealed a negative dependence of the abundance of bacterioplankton, bacteriobenthos, and their ecological-trophic groups on water salinity, as well as direct relations between these biotic components and organic matter in water and bottom sediments. The microbiological indicators of water quality ranked the studied waters as classes III-IV in 2006 and as classes II-III in 2007. The high total abundance of bacteriobenthos (109-1010 cells/g) is a result of the functioning of a marginal filter rather than the direct pollution of the liman.

  17. Scenario simulations of future salinity and ecological consequences in the Baltic Sea and adjacent North Sea areas–implications for environmental monitoring

    PubMed Central

    Vuorinen, Ilppo; Hänninen, Jari; Rajasilta, Marjut; Laine, Päivi; Eklund, Jan; Montesino-Pouzols, Federico; Corona, Francesco; Junker, Karin; Meier, H.E.Markus; Dippner, Joachim W.

    2015-01-01

    Substantial ecological changes occurred in the 1970s in the Northern Baltic during a temporary period of low salinity (S). This period was preceded by an episodic increase in the rainfall over the Baltic Sea watershed area. Several climate models, both global and regional, project an increase in the runoff of the Northern latitudes due to proceeding climate change. The aim of this study is to model, firstly, the effects on Baltic Sea salinity of increased runoff due to projected global change and, secondly, the effects of salinity change on the distribution of marine species. The results suggest a critical shift in the S range 5–7, which is a threshold for both freshwater and marine species distributions and diversity. We discuss several topics emphasizing future monitoring, modelling, and fisheries research. Environmental monitoring and modelling are investigated because the developing alternative ecosystems do not necessarily show the same relations to environment quality factors as the retiring ones. An important corollary is that the observed and modelled S changes considered together with species’ ranges indicate what may appear under a future climate. Consequences could include a shift in distribution areas of marine benthic foundation species and some 40–50 other species, affiliated to these. This change would extend over hundreds of kilometres, in the Baltic Sea and the adjacent North Sea areas. Potential cascading effects, in coastal ecology, fish ecology and fisheries would be extensive, and point out the necessity to develop further the “ecosystem approach in the environmental monitoring”. PMID:25737660

  18. Gelatinous zooplankton in the Belgian part of the North Sea and the adjacent Schelde estuary: Spatio-temporal distribution patterns and population dynamics

    NASA Astrophysics Data System (ADS)

    Vansteenbrugge, Lies; Van Regenmortel, Tina; De Troch, Marleen; Vincx, Magda; Hostens, Kris

    2015-03-01

    Many ocean ecosystems are thought to be heading towards a dominance of gelatinous organisms. However, gelatinous zooplankton has been largely understudied and the absence of quantitative long-term data for the studied area impedes drawing conclusions on potential increasing densities. This study gives a comprehensive overview of the spatio-temporal distribution patterns of gelatinous zooplankton in terms of diversity and density in the Belgian part of the North Sea and the adjacent Schelde estuary, based on monthly and seasonal samples between March 2011 and February 2012. Three Scyphozoa, three Ctenophora and 27 Hydrozoa taxa were identified, including three non-indigenous species: Mnemiopsis leidyi, Nemopsis bachei and Lovenella assimilis. In general, one gelatinous zooplankton assemblage was found across locations and seasons. Average gelatinous zooplankton densities reached up to 18 ind·m-3 near the coast, gradually declining towards the open sea. In the brackish Schelde estuary, average densities remained below 3 ind·m-3. Highest gelatinous zooplankton densities were recorded in summer and autumn. Overall, hydromedusae were the most important group both in terms of diversity and density. The ctenophore Pleurobrachia pileus and the hydromedusa Clytia sp. were present in every season and at every location. Gelatinous zooplankton densities never outnumbered the non-gelatinous zooplankton densities recorded from the WP3 samples. The spatial and temporal distribution patterns seemed to be mainly driven by temperature (season) and salinity (location). Other environmental parameters including (larger) non-gelatinous zooplankton densities (as an important food source) were not retained in the most parsimonious DistLM model.In terms of population dynamics, Beroe sp. seemed to follow the three reproductive cycles of its prey P. pileus and the presence of M. leidyi, which were abundant in a broad size spectrum in summer and autumn. In general, gelatinous zooplankton

  19. Hydrophysical and hydrochemical characteristics of the sea areas adjacent to the estuaries of small rivers of the Russian coast of the Black Sea

    NASA Astrophysics Data System (ADS)

    Zavialov, P. O.; Makkaveev, P. N.; Konovalov, B. V.; Osadchiev, A. A.; Khlebopashev, P. V.; Pelevin, V. V.; Grabovskiy, A. B.; Izhitskiy, A. S.; Goncharenko, I. V.; Soloviev, D. M.; Polukhin, A. A.

    2014-05-01

    This paper presents the results of long-term in situ and satellite measurements at shelf areas adjacent to the estuaries of the small rivers of the Russian coast of the Black Sea (Mezyb, Pshada, Vulan, Tuapse, Bitkha, Sochi, Cudepsta, Mzymta). The quantitative characteristics of the response of the hydrophysical and hydrochemical fields at the sea shelf on the influence of the continental river discharge are presented for each of these areas. A number of indicators of the water quality (the concentrations of the nitrate and nitrite forms of nitrogen, the phosphorus, the silica, the dissolved oxygen, the value of the total alkalinity and pH, the mineral and organic suspended matter, and the chlorophyll a) are considered in the context of the anthropogenic and terrigenous influence. In this paper, the emphasis was placed on the Mzymta River plume at the shelf area adjacent to the city of Sochi, where the measurements were repeatedly performed during the spring flooding conditions in the period from 2007 until 2012. The interannual variability of the water quality indicators and the seasonal and short-term variability of the area and the configuration of the plume, which transports suspended matter and anthropogenic pollution, were considered.

  20. Sediment transport off the Huanghe (Yellow River) delta and in the adjacent Bohai Sea in winter and seasonal comparison

    NASA Astrophysics Data System (ADS)

    Yang, Zuosheng; Ji, Youjun; Bi, Naishuang; Lei, Kun; Wang, Houjie

    2011-07-01

    Based on the data on the current velocity, water temperature, salinity, turbidity and concentration of suspended sediment collected in November 2006 along three survey transects at three time-series, ship-based stations off the Huanghe (Yellow River) delta, and at twenty-four grid survey stations in the adjacent Bohai Sea, sediment transport off the Huanghe delta and in the adjacent Bohai Sea under winter regime were studied and compared with those from the summer season. The homogeneous distribution of salinity, temperature and sediment in the water column indicated a well-mixed body of water. A zone of high suspended sediment concentrations (SSC) >100 mg l -1 with a width of 35 km was identified along the delta coast. Two highest SSC centers were found in the surface and middle water layers around the abandoned Diaokou Huanghe river mouth and the present Huanghe river mouth, and the third one in the bottom layer around the abandoned Qingshuigou Huanghe river mouth. These three highest SSC centers become major sediment source areas in winter. Based on the location of the high bottom shear stress zone, the prevailing wave directions and the protuberant topography of the river mouths, we identified the resuspension origin of the three highest SSC centers caused mostly by the winter storm waves, partially by tidal currents. Suspended sediment flux (SSF) along the three coastal transects indicated that the sediment in the northwest part of the delta was transported northeastward and southeastward along the coast of the recent delta lobe. The SSC and SSF were higher in winter than summer by 1.7-27.1 and 2-122.5 times, respectively, except around the present river mouth. This indicates that the intensity of sediment transport in winter is much stronger than in summer due to the powerful effect of winter storms although the river water and sediment discharges to the sea were much greater in summer. The massive Huanghe sediment to the sea was accumulated in a narrow

  1. Imaging heterogeneity of the crust adjacent to the Dead Sea fault using ambient seismic noise tomography

    NASA Astrophysics Data System (ADS)

    Pinsky, Vladimir; Meirova, Tatiana; Levshin, Anatoli; Hofstetter, Abraham; Kraeva, Nadezda; Barmin, Mikhail

    2013-04-01

    For the purpose of studying the Earth's crust by means of tomography, we investigated cross-correlation functions emerging from long-term observations of propagating ambient seismic noise at pairs of broadband stations in Israel and Jordan. The data was provided by the eight permanent broadband stations of the Israel Seismic Network evenly distributed over Israel and the 30 stations of the DESERT2000 experiment distributed across the Arava Fault (South of the Dead Sea basin). To eliminate the influence of earthquakes and explosions, we have applied the methodology of Bensen et al. (Geophys J Int 169:1239-1260, 2007), including bandpass filtering and amplitude normalization in time and frequency domain. The cross-correlation functions estimated from continuous recordings of a few months were used to extract Rayleigh waves group velocity dispersion curves using automatic version of the frequency-time analysis procedure. Subsequently, these curves have been converted into the Rayleigh wave group velocity maps in the period range 5-20 s and S waves velocity maps in the depth range 5-15 km. In these maps, four velocity anomalies are prominent. Two of them are outlined by the previous reflection-refraction profiles and body wave tomography studies, i.e. a low velocity anomaly corresponds to the area of the extremely deep (down to 14 km) sedimentary infill in the Southern Dead Sea Basin and a high velocity anomaly in the Southern Jordan corresponds to the area of the Precambrian crystalline rocks of the Nubian Shield on the flanks of the Red Sea. The two other anomalies have not been reported before - the high velocity zone close to the Beersheba city and the low velocity anomaly in the region of Samaria-Carmel mountains - Southern Galilee. They have relatively low resolution and hence need further investigations for approving and contouring. The highest contrast between the average Rayleigh wave group velocity (2.7 km/s) and the anomalies is 10-13 %, comparable, however

  2. Spatial distribution and controlling factors of sedimentary bodies in Jiaozhou Bay and Adjacent Sea Areas, Qingdao

    NASA Astrophysics Data System (ADS)

    Dong, Heping; Li, Guangxue; Li, Shuanglin; Li, Shaoquan; Li, Chun

    2011-06-01

    The distributions of thickness of unconsolidated Quaternary sedimentary layers in Jiaozhou Bay and Qingdao offshore area were studied by using 1079-km high-resolution shallow seismic profiles and drilling core data, and the factors controlling the Quaternary evolution were discussed. The results show that such thickness distributions resulted from the coactions of geologic structures and marine hydrodynamic conditions since the Holocene. The geologic structures controlled the slope deposit, proluvial and fluvial fillings since the late Pleistocene. Holocene marine hydrodynamics eroded away sediments at the bay mouth, and tides carried these eroded materials to the sides of the bay mouth and released them there, forming channel-ridge-alternating geomorphic features. During transgressive processes, the sea level rose rapidly, and insufficient sediment supply and tidal actions yielded the relict sediments in the east of Qingdao offshore area.

  3. Interannual to Decadal Variability of Atlantic Water in the Nordic and Adjacent Seas

    NASA Technical Reports Server (NTRS)

    Carton, James A.; Chepurin, Gennady A.; Reagan, James; Haekkinen, Sirpa

    2011-01-01

    Warm salty Atlantic Water is the main source water for the Arctic Ocean and thus plays an important role in the mass and heat budget of the Arctic. This study explores interannual to decadal variability of Atlantic Water properties in the Nordic Seas area where Atlantic Water enters the Arctic, based on a reexamination of the historical hydrographic record for the years 1950-2009, obtained by combining multiple data sets. The analysis shows a succession of four multi-year warm events where temperature anomalies at 100m depth exceed 0.4oC, and three cold events. Three of the four warm events lasted 3-4 years, while the fourth began in 1999 and persists at least through 2009. This most recent warm event is anomalous in other ways as well, being the strongest, having the broadest geographic extent, being surface-intensified, and occurring under exceptional meteorological conditions. Three of the four warm events were accompanied by elevated salinities consistent with enhanced ocean transport into the Nordic Seas, with the exception of the event spanning July 1989-July 1993. Of the three cold events, two lasted for four years, while the third lasted for nearly 14 years. Two of the three cold events are associated with reduced salinities, but the cold event of the 1960s had elevated salinities. The relationship of these events to meteorological conditions is examined. The results show that local surface heat flux variations act in some cases to reinforce the anomalies, but are too weak to be the sole cause.

  4. Temporal distribution of bacterial community structure in the Changjiang Estuary hypoxia area and the adjacent East China Sea

    NASA Astrophysics Data System (ADS)

    Liu, Min; Xiao, Tian; Wu, Ying; Zhou, Feng; Huang, Huiqin; Bao, Shixiang; Zhang, Wuchang

    2012-06-01

    Bacterial community structure and the effects of environmental factors on the microbial community distribution were investigated in the Changjiang Estuary hypoxia area and its adjacent area in the East China Sea (ECS) in June, August and October, 2006. Profiles of bacterial communities were generated by denaturing gradient gel electrophoresis (DGGE) of 16S rRNA genes followed by DNA sequence analysis. The dominant bacterial groups were affiliated to Gammaproteobacteria, Cytophaga-Flavobacteria-Bacteroides (CFB), Deltaproteobacteria, Cyanobacteria and Firmicutes, which were mostly from the marine seawater ecosystem. Effects of environmental factors on the bacterial community distribution were analyzed by the ordination technique of canonical correspondence analysis (CCA). The environmental factors significantly influencing bacterial community structure were different in the three months; dissolved organic carbon (DOC) and temperature in June and nitrite in August. No environmental variables displayed significant influence on the bacterial community at the 5% level in October. The seasonal environmental heterogeneity in the Changjiang Estuary and the adjacent ECS, such as seasonal hydrodynamic conditions and riverine input of nutrients, might be the reason for the difference in the key environmental factors determining the bacterial community in the three months.

  5. Seismic anisotropy and subduction-induced mantle fabrics beneath the Arabian and Nubian Plates adjacent to the Red Sea

    NASA Astrophysics Data System (ADS)

    Elsheikh, Ahmed A.; Gao, Stephen S.; Liu, Kelly H.; Mohamed, Abdelnasser A.; Yu, Youqiang; Fat-Helbary, Raafat E.

    2014-04-01

    For most continental areas, the mechanisms leading to mantle fabrics responsible for the observed anisotropy remain ambiguous, partially due to the lack of sufficient spatial coverage of reliable seismological observations. Here we report the first joint analysis of shear-wave splitting measurements obtained at stations on the Arabian and Nubian Plates adjacent to the Red Sea. More than 1100 pairs of high-quality splitting parameters show dominantly N-S fast orientations at all 47 stations and larger-than-normal splitting times beneath the Afro-Arabian Dome (AAD). The uniformly N-S fast orientations and large splitting times up to 1.5 s are inconsistent with significant contributions from the lithosphere, which is about 50-80 km thick beneath the AAD and even thinner beneath the Red Sea. The results can best be explained by simple shear between the lithosphere and the asthenosphere associated with northward subduction of the African/Arabian Plates over the past 150 Ma.

  6. Controlling factors of summer phytoplankton community in the Changjiang (Yangtze River) Estuary and adjacent East China Sea shelf

    NASA Astrophysics Data System (ADS)

    Jiang, Zhibing; Chen, Jianfang; Zhou, Feng; Shou, Lu; Chen, Quanzhen; Tao, Bangyi; Yan, Xiaojun; Wang, Kui

    2015-06-01

    We analyzed the composition and distribution of phytoplankton in relation to physicochemical factors in the Changjiang (Yangtze River) Estuary and adjacent East China Sea shelf in June and August 2009. Diatoms and dinoflagellates dominated the community, particularly in eutrophic inshore waters controlled by the Changjiang Diluted Water (CDW), coastal current, and upwelling. However, high densities of cyanobacteria and cryptophytes were observed in the oligotrophic offshore waters influenced by the Taiwan Warm Current (TWC) and Kuroshio. In June, the northeastward CDW plume combined with the Yellow Sea Coastal Current induced algal bloom in the northern part of the CE. In August, the enhanced CDW formed two narrow, low-salinity tongues that extended eastward and southward (associated with the upwelling and coastal current), resulting in phytoplankton blooms off the CE and in the Zhejiang coastal waters, respectively. Phytoplankton abundance in August was considerably higher than in June, with increased solar radiation, CDW, and upwelling. The maximum abundance occurred on the surface in inshore turbid waters and on the subsurface (5-30 m) in offshore clear waters with increased stratification. Based on multidimensional scaling and cluster analysis, we found appreciable spatio-temporal variations in algal community composition. Different ecological groups corresponded with hydrographic distributions. Canonical correspondence analysis showed that nutrients, salinity, temperature, and suspended particulate matter were the main variables associated with community distribution. We suggest that the variations in summer phytoplankton community are highly correlated with the significant monthly and spatial variability in physicochemical properties, which are primarily controlled by the CDW and TWC.

  7. Overview of the Pre-YMC2015 campaign over the southwestern coastal land and adjacent sea of Sumatera Island, Indonesia

    NASA Astrophysics Data System (ADS)

    Mori, Shuichi; Katsumata, Masaki; Yoneyama, Kunio; Suzuki, Kenji; Hayati, Noer; Syamsudin, Fadli

    2016-04-01

    An international research project named Years of the Maritime Continent (YMC) is planned during 2017-2019 to expedite the progress of improving understanding and prediction of local multi-scale variability of the Maritime Continent (MC) weather-climate system and its global impact through observations and modeling exercises. We carried out a campaign observation over the southwestern coastal land and adjacent sea of Sumatera Island, Indonesia, during November-December 2015 as a pilot study of the YMC to examine land-ocean coupling processes in mechanisms of coastal heavy rain band (CHeR) along Sumatera Island and further potential scientific themes in the coming YMC. We deployed two land observation sites at Bengkulu city (3.86S, 102.34E) in the southwestern coast of Sumatera Island with various kinds of instruments including an X-band dual polarimetric (DP) radar and a C-band Doppler radar, and the R/V Mirai approximately 50 km southwest (4.07S, 101.90E) of the land stations with a C-band DP radar. We made 3 hourly soundings at Bengkulu and the R/V Mirai during 09 November - 25 December (47 days) and 24 November - 17 December (24 days), respectively. In addition, 18 videosondes observations, which could identify precipitation particles by an onboard camera in and out of rainclouds, were performed under heavy rainfall condition to examine cloud microphysical processes as well as simultaneous RHI observations with the Mirai DP radar. Whereas rainfall amount during the period was less than that of climatological view due to the Godzilla El-Nino event in this rainy season, we found concrete diurnal variation with thunderstorms in the evening along the foothills of coastal land and widely spread stratiform precipitation mainly over the adjacent sea due to the passage of Madden-Julian Oscillation (MJO) convection with strong westerly wind in the lower troposphere during the former and latter halves of the campaign period, respectively. Diurnally developed thunderstorms

  8. Distribution of Pasiphaea japonica larvae in submarine canyons and adjacent continental slope areas in Toyama Bay, Sea of Japan

    NASA Astrophysics Data System (ADS)

    Nanjo, Nobuaki; Katayama, Satoshi

    2014-09-01

    The horizontal and vertical distribution of Pasiphaea japonica larvae, which included larval stages and postlarval or later stages, were investigated in Toyama Bay located in central Japan. The horizontal distributions in the inner part of the bay were investigated by oblique hauls from 10 m above the sea-bottom to the surface using a Remodeled NORPAC net (LNP net) in May, August, November 2005, January, March, April, July, September, December 2006, March-September, November-December 2007, and January-March 2008. The vertical distributions were investigated by concurrent horizontal hauls at the depths of 0, 50, 100, 150, 200, and 250 m using a Motoda net (MTD net) in January, March, April, July, September, and December 2006. Mean density of larvae was higher in submarine canyons which dissect the continental shelf and run to the mouth of river, than adjacent continental slope areas. Larvae densely aggregated in the canyon head. Vertical distribution of the larval stages concentrated in the depth range of 100-150 m in both daytime and nighttime, and larvae in the postlarval or later stages showed diel vertical distribution over a wider depth range than larval stages. Our results indicate the possibility of a larval aggregation in energy-rich habitats, and indicated two important roles of submarine canyons, which were larval retention and high food supply.

  9. Sea-Salt Aerosol Forecasts Compared with Wave and Sea-Salt Measurements in the Open Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Kishcha, P.; Starobinets, B.; Bozzano, R.; Pensieri, S.; Canepa, E.; Nickovie, S.; di Sarra, A.; Udisti, R.; Becagli, S.; Alpert, P.

    2012-03-01

    Sea-salt aerosol (SSA) could influence the Earth's climate acting as cloud condensation nuclei. However, there were no regular measurements of SSA in the open sea. At Tel-Aviv University, the DREAM-Salt prediction system has been producing daily forecasts of 3-D distribution of sea-salt aerosol concentrations over the Mediterranean Sea (http://wind.tau.ac.il/saltina/ salt.html). In order to evaluate the model performance in the open sea, daily modeled concentrations were compared directly with SSA measurements taken at the tiny island of Lampedusa, in the Central Mediterranean. In order to further test the robustness of the model, the model performance over the open sea was indirectly verified by comparing modeled SSA concentrations with wave height measurements collected by the ODAS Italia 1 buoy and the Llobregat buoy. Model-vs.-measurement comparisons show that the model is capable of producing realistic SSA concentrations and their day-today variations over the open sea, in accordance with observed wave height and wind speed.

  10. Modern transport and deposition of settling particles in the northern South China Sea: Sediment trap evidence adjacent to Xisha Trough

    NASA Astrophysics Data System (ADS)

    Liu, Jianguo; Clift, Peter D.; Yan, Wen; Chen, Zhong; Chen, Han; Xiang, Rong; Wang, Dongxiao

    2014-11-01

    Studies on modern sediment transport and deposition, especially studies analyzing settling particles collected with sediment traps, have rarely been carried out in the northern South China Sea. Using sediment trap time series data from Site XS1 (17°24.5‧N, 110°55.0‧E, water depth 1690 m) adjacent to the Xisha Trough, variations in sediment source through time have been reconstructed. These observations include total particle flux (TPF) and current data, grain size distributions, and clay mineral compositions obtained from two sediment traps deployed in 500 m and 1500 m water depth, respectively. Time series records at Site XS1 changed seasonally for both sampled layers. TPF in the lower layer (426 mg/m2/d) was several times that of the upper layer (113 mg/m2/d) and is affected by lateral transport. However, mean grain size (Mz) of the upper layer is greater that of the lower layer (29 vs10 μm) due to contributions from biogenic materials. There are no clear seasonal changes in clay mineral assemblage in either the upper or lower layers. The annual percentages of four main clay minerals were 82-83% illite, 7-9% kaolinite, 6-8% chlorite and 1-3% smectite. Taiwan was the dominant sediment source (42-74%), while sediment contributions from the Red River and Annamite Chain account for 23-53% and 0-15%, respectively. Sediment supply from Taiwan could be explained by deep water current flow, while coastal currents may aid sediment transport from the Red River and small mountainous rivers of central Vietnam.

  11. Distribution of polybrominated diphenyl ethers in sediments of the Pearl River Delta and adjacent South China Sea.

    PubMed

    Mai, Bixian; Chen, Shejun; Luo, Xiaojun; Chen, Laiguo; Yang, Qingshu; Sheng, Guoying; Peng, Pingan; Fu, Jiamo; Zeng, Eddy Y

    2005-05-15

    Spatial and temporal distributions of polybrominated diphenyl ethers (PBDEs) in sediments of the Pearl River Delta (PRD) and adjacent South China Sea (SCS) of southern China were examined. A total of 66 surface sediment samples were collected and analyzed to determine the concentrations of 10 PBDE congeners (BDE-28, -47, -66, -100, -99, -154, -153, -138, -183, and -209). The concentrations of BDE-209 and SigmaPBDEs (defined as the sum of all targeted PBDE congeners except for BDE-209) ranged from 0.4 to 7340 and from 0.04 to 94.7 ng/g, respectively. The SigmaPBDEs concentrations were mostly < 50 ng/g, within the range for riverine and coastal sediments around the world, whereas the BDE-209 concentrations at the most contaminated sites were at the high end of the worldwide figures. Congener compositions were dominated by BDE-209 (72.6 - 99.7%), with minor contributions from penta- and octa-BDEs. Slightly different PBDE compositions were observed among samples collected from different locations, attributable to possible decomposition of highly brominated congeners and/or redistribution between particles of various sizes during atmospheric or fluvial transportation. The PBDE patterns in the SCS and Pearl River Estuary sediments were similar to those in sediments of the Zhujiang and Dongjiang Rivers, reflecting the widespread influence from local inputs. Analyses of two short sediment cores collected from the Pearl River Estuary showed that concentrations of BDE-209 rapidly increased in the upper layers of both cores, coincident with the growth of the electronics manufacturing capacities in the PRD region. The major sources of PBDEs were probably waste discharges from the cities of Guangzhou, Dongguan, and Shenzhen, the three fastest growing urban centers in the PRD. PMID:15952354

  12. Macrofauna under sea ice and in the open surface layer of the Lazarev Sea, Southern Ocean

    NASA Astrophysics Data System (ADS)

    Flores, Hauke; van Franeker, Jan-Andries; Cisewski, Boris; Leach, Harry; Van de Putte, Anton P.; Meesters, Erik (H. W. G.); Bathmann, Ulrich; Wolff, Wim J.

    2011-10-01

    A new fishing gear was used to sample the macrozooplankton and micronekton community in the surface layer (0-2 m) under ice and in open water, the Surface and Under Ice Trawl (SUIT). In total, 57 quantitative hauls were conducted in the Lazarev Sea (Southern Ocean) during 3 different seasons (autumn 2004, winter 2006, summer 2007/2008). At least 46 species from eight phyla were caught in all 3 seasons combined. Biomass density was dominated by Antarctic krill Euphausia superba. The average biomass density was highest under the winter sea ice and lowest under the young ice in autumn. In summer, macrozooplankton biomass was dominated by ctenophores in open water and by Antarctic krill under ice. The community composition varied significantly among seasons, and according to the presence of sea ice. The response of the community composition to the presence of sea ice was influenced by species that were significantly more abundant in open water than under ice ( Cyllopus lucasii, Hyperiella dilatata), only seasonally abundant under ice ( Clione antarctica), or significantly associated with sea ice ( Eusirus laticarpus). A number of abundant species showed distinct diel patterns in the surface occurrence both under ice and in open water, indicating that the surface layer serves as a foraging ground predominantly at night. Our results emphasize the potential of a number of non-euphausiid macrozooplankton and micronekton species to act as energy transmitters between the production of sea ice biota and the pelagic food web. By providing a regional-scale quantitative record of macrofauna under Antarctic sea ice covering 3 seasons, this study adds new and direct evidence that the ice-water interface layer is a major functional node in the ecosystem of the Antarctic seasonal sea ice zone.

  13. Sea Ice Characteristics and the Open-Linked Data World

    NASA Astrophysics Data System (ADS)

    Khalsa, S. J. S.; McGuinness, D. L.; Duerr, R.; Pulsifer, P. L.; Fox, P. A.; Thompson, C.; Yan, R.

    2014-12-01

    The audience for sea ice data sets has broadened dramatically over the past several decades. Initially the National Snow and Ice Data Center (NSIDC) sea ice products were used primarily by sea ice specialists. However, now they are in demand by researchers in many different domains and some are used by the public. This growth in the number and type of users has presented challenges to content providers aimed particularly at supporting interdisciplinary and multidisciplinary data use. In our experience, it is generally insufficient to simply make the data available as originally formatted. New audiences typically need data in different forms; forms that meet their needs, that work with their specific tools. Moreover, simple data reformatting is rarely enough. The data needs to be aggregated, transformed or otherwise converted into forms that better serve the needs of the new audience. The Semantic Sea Ice Interoperability Initiative (SSIII) is an NSF-funded research project aimed at making sea ice data more useful to more people using semantic technologies. The team includes domain and science data experts as well as knowledge representation and linked data experts. Beginning with a series of workshops involving members of the operations, sea ice research and modeling communities, as well as members of local communities in Alaska, a suite of ontologies describing the physical characteristics of sea ice have been developed and used to provide one of NSIDC's data sets, the operational Arctic sea ice charts obtained from the Canadian Ice Center, as open-linked data. These data extend nearly a decade into the past and can now be queried either directly through a publicly available SPARQL end point (for those who are familiar with open-linked data) or through a simple Open Geospatial Consortium (OGC) standards map-based query tool. Questions like "What were the characteristics (i.e., sea ice concentration, form and stage of development) of the sea ice in the region

  14. Contribution of the upper river, the estuarine region, and the adjacent sea to the heavy metal pollution in the Yangtze Estuary.

    PubMed

    Yin, Su; Wu, Yuehan; Xu, Wei; Li, Yangyang; Shen, Zhenyao; Feng, Chenghong

    2016-07-01

    To determine whether the discharge control of heavy metals in the Yangtze River basin can significantly change the pollution level in the estuary, this study analyzed the sources (upper river, the estuarine region, and the adjacent sea) of ten heavy metals (As, Cd, Co, Cr, Cu, Hg, Ni, Pb, Sb, and Zn) in dissolved and particulate phases in the surface water of the estuary during wet, normal, and dry seasons. Metal sources inferred from section fluxes agree with those in statistical analysis methods. Heavy metal pollution in the surface water of Yangtze Estuary primarily depends on the sediment suspension and the wastewater discharge from estuary cities. Upper river only constitutes the main source of dissolved heavy metals during the wet season, while the estuarine region and the adjacent sea (especially the former) dominate the dissolved metal pollution in the normal and dry seasons. Particulate metals are mainly derived from sediment suspension in the estuary and the adjacent sea, and the contribution of the upper river can be neglected. Compared with the hydrologic seasons, flood-ebb tides exert a more obvious effect on the water flow directions in the estuary. Sediment suspension, not the upper river, significantly affects the suspended particulate matter concentration in the estuary. PMID:27155472

  15. Copepod communities, production and grazing in the Turkish Straits System and the adjacent northern Aegean Sea during spring

    NASA Astrophysics Data System (ADS)

    Zervoudaki, S.; Christou, E. D.; Assimakopoulou, G.; Örek, H.; Gucu, A. C.; Giannakourou, A.; Pitta, P.; Terbiyik, T.; Yϋcel, N.; Moutsopoulos, T.; Pagou, K.; Psarra, S.; Özsoy, E.; Papathanassiou, E.

    2011-06-01

    The Mediterranean and the Black Seas are connected through Bosphorus, Marmara Sea and Dardanelles (Turkish Straits System, TSS). In this study, we examined the spatial distribution of copepods and investigate their production and grazing. The aim was to understand the transfer of phytoplankton/microzooplankton production up the food chain in TSS and Aegean Sea during spring. The phytoplankton and microzooplankton biomass and production showed a clear decreasing trend from Bosphorus to the Aegean Sea, whereas copepod biomass did not reveal any distinct trend and only the number of copepod species increased from Bosphorus to the Aegean Sea. Production of copepods and egg production showed similar trends except for the Bosphorus, where production of copepods was very low due to the low copepod biomass in this area. In all areas, the copepod carbon demand was largely met by phytoplankton and microzooplankton production. However, only a low amount of primary production was consumed by copepods and production appeared to flow mostly through other pathways (microbial loop) and/or sediment on the bottom. The results of this study confirm the hypothesis that there is a substantial differentiation within pelagic food web structure and carbon flow from Bosphorus to the Aegean Sea.

  16. Analyzing the Modeled Tidal Signal in the Bab El Mandeb Strait and Adjacent Red Sea and Gulf of Aden Waters

    NASA Astrophysics Data System (ADS)

    Guillory, R. N. B.

    2014-12-01

    The tidal forces that dominate the Bab el Mandeb region are influenced by both the generally semi-diurnal tides in the Red Sea and mixed tides in the Gulf of Aden. Also, the tidal ranges are much greater in the Gulf of Aden (~ 2 m) than in the Red Sea (< 1m), which further complicates the tidal signal in Bab el Mandeb Strait. The Red Sea Regional Navy Coastal Model (NCOM), which includes the entire Red Sea, and the western part of the Gulf of Aden at a 1 km resolution, will be evaluated on how well it replicates the tidal signal described in literature and historical observations. In addition, the model will be compared to available temperature/salinity in situ profiles. NCOM incorporates the Oregon State University Tide Model, which should allow the ocean model to accurately reflect the transitional tides in the Bab el Mandeb Strait. Preliminary estimates indicate that the model replicates the overall circulation pattern seen in literature and the fact that there are higher tidal amplitudes in the Gulf of Aden than in the Red Sea. Approved for Public Release, Distribution Unlimited

  17. Deep-sea epibiotic hydroids from the abyssal plain adjacent to the Kuril-Kamchatka Trench with description of Garveia belyaevi sp. nov. (Hydrozoa, Bougainvilliidae)

    NASA Astrophysics Data System (ADS)

    Stepanjants, Sofia D.; Chernyshev, Alexey V.

    2015-01-01

    Examination of material collected by the German-Russian KuramBio Deep-Sea Expedition to the abyssal plain adjacent to the Kuril-Kamchatka Trench revealed about 17 hydroid species, including two species presumably new to science. Before the KuramBio Expedition only fragments of the unidentified hydroids and Cryptolaria sp. were collected in the Kuril-Kamchatka Trench from depths exceeding 3000 m. Descriptions of three species of epibiotic hydroids (including one new species, Garveia belyaevi sp. nov.) are presented herein. A colony of G. belyaevi sp. nov. (the third deep-sea and deepest species of the wide distributed genus Garveia) was attached to the spines of unidentified irregular sea urchins from depths 5217 to 5229 m. Нalitholus (?) sp. (Hydrozoa, Anthoathecata) colonized the skin of spoon worms (Echiura) but could not be identified to species level because the mature medusa stage was absent in the material. An unidentified juvenile polyp (Pandeidae) was found on the bryozoan Tricitella minini attached to spines of irregular sea urchins Echinosigra amphora. Colonial sedentary organisms inhabiting abyssal plains with soft bottoms may colonize invertebrates which are seldom used as substrates for epibiota in shallow waters. Epibiosis among abyssal colonial invertebrates, though extremely poorly studied, appears to be rather frequent.

  18. Atmospheric Response to Weddell Sea Open-Ocean Polynya

    SciTech Connect

    Hodos, Travis; Weijer, Wilbert

    2015-07-02

    The atmospheric conditions associated with the rare Weddell Sea open ocean polynya are investigated. The polynya has not been seen since 1976, so data on the event is scarce. The CESM high resolution model is used to investigate multiple atmospheric variables. We analyze three years of polynyas, which are also compared to three years without a polynya. The surface temperature, sensible heat flux, latent heat flux, humidity, average wind speed, precipitation, longwave flux, and shortwave flux all increased over the polynya. The sensible heat flux had a higher magnitude than the latent heat flux because conduction and convection were the primary drivers of heat flux. A combination of increased latent heat flux and humidity led to an increase in precipitation. Increased longwave downwelling flux over the polynya indicated the presence of clouds over the polynya. Lastly, the sea level pressure was consistently lower over the polynya because of the presence of a thermal low generated by thermally driven convective updrafts.

  19. 76 FR 79764 - Use of Foreign-Flag Anchor Handling Vessels in the Beaufort Sea or Chukchi Sea Adjacent to Alaska

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-22

    ... Maritime Administration Use of Foreign-Flag Anchor Handling Vessels in the Beaufort Sea or Chukchi Sea...-flag anchor handling vessels in certain cases (and for a limited period of time) if no U.S.-flag... the Maritime Administration determines that U.S.- flag vessels are not suitable and...

  20. Species distribution within the free-living marine nematode genus Dichromadora in the Weddell Sea and adjacent areas

    NASA Astrophysics Data System (ADS)

    Vermeeren, Hannelore; Vanreusel, Ann; Vanhove, Sandra

    2004-07-01

    Studies of Antarctic, free-living, marine nematodes are mostly restricted to genus level. In the current study, the genus Dichromadora (Kreis, H.A., 1929. Capita Zoologica 2(7), 1-98) is analysed to species level. Dichromadora is one of the genera that are frequently present along the continental margin of the eastern Weddell Sea. Samples were retrieved from the 1000-2000 m depth line in the eastern Weddell Sea (Halley Bay, Vestkapp and Kapp Norvegia), South Sandwich Trench and the Drake Passage. Eight species are distinguished within the genus Dichromadora of which seven are new to science. Out of these seven species, five are described taxonomically: Dichromadora weddellensis sp. n. , Dichromadora southernis sp. n. , Dichromadora polarsternis sp. n., Dichromadora parva sp. n., and Dichromadora polaris sp. n. The two other species ( D. spec A, D. spec B) receive, as to the scarcety of available specimens, no scientific name. The distribution of the Dichromadora species from Antarctica are discussed in the context of deep-sea (1000-2000 m) observations in Arctic, Atlantic, Pacific and Indian oceans.

  1. Exchanges between the open Black Sea and its North West shelf

    NASA Astrophysics Data System (ADS)

    Shapiro, Georgy; Wobus, Fred; Zhou, Feng

    2014-05-01

    Exchanges between the vast NW shelf and the deep basin of the Black Sea play a significant role in maintaining the balance of nutrients, heat content and salinity of the shelf waters. Nearly 87 % of the Black Sea is entirely anoxic below 70 to 200m and contains high levels of hydrogen sulphide (Zaitsev et al, 2001), and this makes the shelf waters particularly valuable for maintaining the Black Sea ecosystem in good health. The increase in salinity of shelf waters occurs partially due to exchanges with more saline open sea waters and represents a threat to relics and endemic species. The shelf-break is commonly considered the bottle-neck of the shelf-deep sea exchanges (e.g. (Huthnance, 1995, Ivanov et al, 1997). Due to conservation of potential vorticity, the geostrophic currents flow along the contours of constant depth. However the ageostrophic flows (Ekman drift, mesoscale eddies, filaments, internal waves) are not subject to the same constraints. It has been shown that during the winter well mixed cold waters formed on the North West shelf propagate into the deep sea, providing an important mechanism for the replenishment of the Cold Intermediate Layer ( Staneva and Stanev, 1997). However, much less is known about exchanges in the warm season. In this study, the transports of water, heat and salt between the northwestern shelf and the adjacent deep basin of the Black Sea are investigated using a high-resolution three-dimensional primitive equation model, NEMO-SHELF-BLS (Shapiro et al, 2013). It is shown that during the period from April to August, 2005, both onshore and offshore cross-shelf break transports in the top 20 m were as high as 0.24 Sv on average, which was equivalent to the replacement of 60% of the volume of surface shelf waters (0 - 20 m) per month. Two main exchange mechanisms are studied: (i) Ekman transport, and (ii) transport by mesoscale eddies and associated meanders of the Rim Current. The Ekman drift causes nearly uniform onshore or

  2. Distribution of organochlorine pesticides in sediments from Yangtze River Estuary and the adjacent East China Sea: implication of transport, sources and trends.

    PubMed

    Zhou, Shanshan; Yang, Huayun; Zhang, Anping; Li, Yi-Fan; Liu, Weiping

    2014-11-01

    Thirty-eight surface sediments and two sediment cores were collected from Yangtze River Estuary (YRE) and adjacent East China Sea (ECS) to study the distribution patterns, origins, potential transport and burden of organochlorine pesticides (OCPs) in the marginal sea. Residues of OCPs ranged from 0.190 to 5.17 ng g(-1) dry weight with a distinct "band type" pattern under the control of Yangtze River inputs and ECS circulation system. Differences in transmission media and redox conditions in situ respectively resulted in the divergent distributions of α/β-HCH and DDD/DDE. The compositional pattern analysis implied that OCPs in the inner shelf of ECS were derived from both "weathered" and fresh sources, whereas those in the outer shelf of ECS had undergone high metabolism. Concurrent with the land-sea migration, vertical profiles of sediment cores showed increasing trends or rebound since the 1990s, characteristic of two evident "jumps" of DDE+DDD/DDT and DDT/DDE ratios. Moreover, the primary distribution pattern founded for HCHs and the considerable mass inventories calculated (6.20 metric tones for OCPs) together suggested that the contaminated sediments in the studied area to be a potential source of OCPs to the global ocean. PMID:25113180

  3. The Application of DNA Barcodes for the Identification of Marine Crustaceans from the North Sea and Adjacent Regions

    PubMed Central

    Raupach, Michael J.; Barco, Andrea; Steinke, Dirk; Beermann, Jan; Laakmann, Silke; Mohrbeck, Inga; Neumann, Hermann; Kihara, Terue C.; Pointner, Karin; Radulovici, Adriana; Segelken-Voigt, Alexandra; Wesse, Christina; Knebelsberger, Thomas

    2015-01-01

    During the last years DNA barcoding has become a popular method of choice for molecular specimen identification. Here we present a comprehensive DNA barcode library of various crustacean taxa found in the North Sea, one of the most extensively studied marine regions of the world. Our data set includes 1,332 barcodes covering 205 species, including taxa of the Amphipoda, Copepoda, Decapoda, Isopoda, Thecostraca, and others. This dataset represents the most extensive DNA barcode library of the Crustacea in terms of species number to date. By using the Barcode of Life Data Systems (BOLD), unique BINs were identified for 198 (96.6%) of the analyzed species. Six species were characterized by two BINs (2.9%), and three BINs were found for the amphipod species Gammarus salinus Spooner, 1947 (0.4%). Intraspecific distances with values higher than 2.2% were revealed for 13 species (6.3%). Exceptionally high distances of up to 14.87% between two distinct but monophyletic clusters were found for the parasitic copepod Caligus elongatus Nordmann, 1832, supporting the results of previous studies that indicated the existence of an overlooked sea louse species. In contrast to these high distances, haplotype-sharing was observed for two decapod spider crab species, Macropodia parva Van Noort & Adema, 1985 and Macropodia rostrata (Linnaeus, 1761), underlining the need for a taxonomic revision of both species. Summarizing the results, our study confirms the application of DNA barcodes as highly effective identification system for the analyzed marine crustaceans of the North Sea and represents an important milestone for modern biodiversity assessment studies using barcode sequences. PMID:26417993

  4. New insights from seismic tomography on the complex geodynamic evolution of two adjacent domains: Gulf of Cadiz and Alboran Sea

    NASA Astrophysics Data System (ADS)

    Monna, S.; Cimini, G. B.; Montuori, C.; Matias, L.; Geissler, W. H.; Favali, P.

    2013-04-01

    In this study, we present a three-dimensional P wave upper-mantle tomography model of the southwest Iberian margin and Alboran Sea based on teleseismic arrival times recorded by Iberian and Moroccan land stations and by a seafloor network deployed for 1 year in the Gulf of Cadiz area during the European Commission Integrated observations from NEAR shore sourcES of Tsunamis: towards an early warning system (EC NEAREST) project. The three-dimensional model was computed down to 600 km depth. The tomographic images exhibit significant velocity contrasts, as large as 3%, confirming the complex evolution of this plate boundary region. Prominent high-velocity anomalies are found beneath Betics-Alboran Sea, off-shore southwest Portugal, and north Portugal, at sublithospheric depths. The transition zones between high- and low-velocity anomalies in southwest and south Iberia are associated to the contact of oceanic and continental lithosphere. The fast structure below the Alboran Sea-Granada area depicts an L-shaped body steeply dipping from the uppermost mantle to the transition zone where it becomes less curved. This anomaly is consistent with the results of previous tomographic investigations and recent geophysical data such as stress distribution, GPS measurements of plate motion, and anisotropy patterns. In the Atlantic domain, under the Horseshoe Abyssal Plain, the main feature is a high-velocity zone found at uppermost mantle depths. This feature appears laterally separated from the positive anomaly recovered in the Alboran domain by the interposition of low-velocity zones which characterize the lithosphere beneath the southwest Iberian peninsula margin, suggesting that there is no continuity between the high-velocity anomalies of the two domains west and east of the Gibraltar Strait.

  5. Evidence of low density sub-crustal underplating beneath western continental region of India and adjacent Arabian Sea: Geodynamical considerations

    NASA Astrophysics Data System (ADS)

    Pandey, O. P.; Agrawal, P. K.; Negi, J. G.

    1996-07-01

    The known high mobility of the Indian subcontinent during the period from 80 to 53 Ma has evoked considerable interest in recent times. It appears to have played an important role in shaping the subcontinental structures of western India and the adjoining Arabian Sea. During this period, a major catastrophic event took place in the form of Deccan volcanism, which coincides with the biological mass extinction at the K-T boundary, including the death of dinosaurs. The origin of Deccan volcanism is still being debated. Geophysically, western India and its offshore regions exhibit numerous prominent anomalies which testify to the abnormal nature of the underlying crust-lithosphere. In this work, we develop a two-dimensional structural model of these areas along two long profiles extending from the eastern basin of the Arabian Sea to about 1000 km inland. The model, derived from the available gravity data in the oceanic and continental regions, is constrained by seismic and other relevant information in the area, and suggests, for the first time, the presence of an extensive low-density (2.95-3.05 g/cm 3) sub-crustal underplating. Such a layer is found to occur between depths of 11 and 20 km in the eastern basin of the Arabian Sea, and betweeen 45 and 60 km in the continental region where it is sandwiched in the lower lithosphere. The low density may have been caused as a result of serpentinization or fractionation of magma by a process related in some way to the Deccan volcanic event. Substantial depletion of both oceanic and continental lithosphere is indicated. We hypothesize that the present anatomy of the deformed lithosphere of the region at the K-T boundary is the result of substantial melt generated owing to frictional heat possibly giving rise to a hot cell like condition at the base of the lithosphere, resulting from the rapid movement of the Indian subcontinent between 80 and 53 Ma.

  6. Flux and budget of BC in the continental shelf seas adjacent to Chinese high BC emission source regions

    NASA Astrophysics Data System (ADS)

    Fang, Yin; Chen, Yingjun; Tian, Chongguo; Lin, Tian; Hu, Limin; Huang, Guopei; Tang, Jianhui; Li, Jun; Zhang, Gan

    2015-07-01

    This study conducted the first comprehensive investigation of sedimentary black carbon (BC) concentration, flux, and budget in the continental shelves of "Bohai Sea (BS) and Yellow Sea (YS)," based on measurements of BC in 191 surface sediments, 36 riverine water, and 2 seawater samples, as well as the reported data set of the atmospheric samples from seven coastal cities in the Bohai Rim. BC concentrations in these matrices were measured using the method of thermal/optical reflectance. The spatial distribution of the BC concentration in surface sediments was largely influenced by the regional hydrodynamic conditions, with high values mainly occurring in the central mud areas where fine-grained particles (median diameters > 6 Φ (i.e., <0.0156 mm)) were deposited. The BC burial flux in the BS and YS ranged from 4 to 1100 µg/cm2 yr, and averaged 166 ± 200 µg/cm2 yr, which was within the range of burial fluxes reported in other continental shelf regimes. The area-integrated sedimentary BC sink flux in the entire BS and YS was ~325 Gg/yr, and the BS alone contributed ~50% (~157 Gg/yr). The BC budget calculated in the BS showed that atmospheric deposition, riverine discharge, and import from the Northern Yellow Sea (NYS) each contributed ~51%, ~47%, and ~2%. Therefore, atmospheric deposition and riverine discharge dominated the total BC influx (~98%). Sequestration to bottom sediments was the major BC output pattern, accounting for ~88% of the input BC. Water exchange between the BS and the NYS was also an important BC transport route, with net BC transport from the BS to the NYS.

  7. Community composition and distribution of sulfate- and sulfite-reducing prokaryotes in sediments from the Changjiang estuary and adjacent East China Sea

    NASA Astrophysics Data System (ADS)

    He, Hui; Zhen, Yu; Mi, Tiezhu; Xu, Bochao; Wang, Guoshan; Zhang, Yu; Yu, Zhigang

    2015-11-01

    Sulfate- and sulfite-reducing prokaryotes (SSRP) communities play a vital role in both sulfur and carbon cycles. Community composition and abundance of SSRP were investigated using dissimilatory sulfite reductase β subunit (dsrB) gene sequencing in sediments from the Changjiang estuary and its adjacent area in the East China Sea (ECS). Clone libraries were constructed and real-time fluorescence quantitative polymerase chain reaction (qPCR) was applied to understand the community information of SSRP. In addition to sequences affiliated to sulfate-reducing prokaryotes (SRP), those affiliated with sulfite-reducing prokaryotes (SiRP) were also observed. Four phylotypes of SRP in this study showed genetic similarity to Desulfobulbaceae, Syntrophobacteraceae, Desulfobacteraceae and Peptococcaceae, and an unknown group that could not be clearly affiliated with known lineages was found. Salinity, temperature and contents of total organic carbon (TOC) were most closely correlated with the SSRP communities by canonical correspondence analysis (CCA). 210Pb activities demonstrated the sedimentary environment at S33 was more stable than that at S31. Intense resuspension and reconstruction of sediments made the vertical abundance profile of SSRP fluctuate violently. For surface sediments, the dsrB gene copy numbers near the Changjiang estuary were higher than those in the mouth of Hangzhou Bay and the mud deposits along the Zhejiang coast, and contents of TOC were positively related to the copy numbers of dsrB gene. Our data provided valuable information to achieve a better understanding of the potential role of SSRP in sediments from the Changjiang estuary and adjacent East China Sea.

  8. Seasonal changes in phytoplankton biomass and dominant species in the Changjiang River Estuary and adjacent seas: General trends based on field survey data 1959-2009

    NASA Astrophysics Data System (ADS)

    Yang, Shu; Han, Xiurong; Zhang, Chuansong; Sun, Baiye; Wang, Xiulin; Shi, Xiaoyong

    2014-12-01

    The characteristics of seasonal variation in phytoplankton biomass and dominant species in the Changjiang River Estuary and adjacent seas were discussed based on field investigation data from 1959 to 2009. The field data from 1981 to 2004 showed that the Chlorophyll- a concentration in surface seawater was between 0.4 and 8.5 μg dm-3. The seasonal changes generally presented a bimodal trend, with the biomass peaks occurring in May and August, and Chlorophyll-a concentration was the lowest in winter. Seasonal biomass changes were mainly controlled by temperature and nutrient levels. From the end of autumn to the next early spring, phytoplankton biomass was mainly influenced by temperature, and in other seasons, nutrient level (including the nutrient supply from the terrestrial runoffs) was the major influence factor. Field investigation data from 1959 to 2009 demonstrated that diatoms were the main phytoplankton in this area, and Skeletonema costatum, Pseudo-nitzschia pungens, Coscinodiscus oculus-iridis, Thalassinoema nitzschioides, Paralia sulcata, Chaetoceros lorenzianus, Chaetoceros curvisetus, and Prorocentrum donghaiense Lu were common dominant species. The seasonal variations in major dominant phytoplankton species presented the following trends: 1) Skeletonema (mainly S. costatum) was dominant throughout the year; and 2) seasonal succession trends were Coscinodiscus (spring) → Chaetoceros (summer and autumn) → Coscinodiscus (winter). The annual dominance of S. costatum was attributed to its environmental eurytopicity and long standing time in surface waters. The seasonal succession of Coscinodiscus and Chaetoceros was associated with the seasonal variation in water stability and nutrient level in this area. On the other hand, long-term field data also indicated obvious interannual variation of phytoplankton biomass and community structure in the Changjiang River Estuary and adjacent seas: average annual phytoplankton biomass and dinoflagellate

  9. Receiver function constraints on crustal seismic velocities and partial melting beneath the Red Sea rift and adjacent regions, Afar Depression

    NASA Astrophysics Data System (ADS)

    Reed, Cory A.; Almadani, Sattam; Gao, Stephen S.; Elsheikh, Ahmed A.; Cherie, Solomon; Abdelsalam, Mohamed G.; Thurmond, Allison K.; Liu, Kelly H.

    2014-03-01

    The Afar Depression is an ideal locale for the investigation of crustal processes involved in the transition from continental rifting to oceanic spreading. To provide relatively high resolution images of the crust beneath the Red Sea rift (RSR) represented by the Tendaho graben in the Afar Depression, we deployed an array of 18 broadband seismic stations in 2010 and 2011. Stacking of about 2300 receiver functions from the 18 and several nearby stations along the ~200 km long array reveals an average crustal thickness of 22±4 km, ranging from ~17 km near the RSR axis to 30 km within the overlap zone between the Red Sea and Gulf of Aden rifts. The resulting anomalously high Vp/Vs ratios decrease from 2.40 in the southwest to 1.85 within the overlap zone. We utilize theoretical Vp and melt fraction relationships to obtain an overall highly reduced average crustal Vp of ~5.1 km/s. The melt percentage is about 10% beneath the RSR while the overlap zone contains minor quantities of partial melt. The observed high Vp/Vs values beneath most of the study area indicate widespread partial melting beneath the southwest half of the profile, probably as a result of gradual eastward migration of the RSR axis. Our results also suggest that the current extensional strain in the lower crust beneath the region is diffuse, while the strain field in the upper crust is localized along narrow volcanic segments. These disparate styles of deformation imply a high degree of decoupling between the upper and lower crust.

  10. Multi-Scale Interactions Associated with the Monsoon Onset Over South China Sea and Adjacent Regions during SCSMEX-98

    NASA Technical Reports Server (NTRS)

    Lau, William K. M.; Li, X.; Wu, H.-T.

    1999-01-01

    Using data collected during The South China Sea Monsoon Experiment (SCSMEX) (1998) as well as from the TRMM Microwave-Imager (TMI) and precipitation radar (PR), we have studied the multi-scale interactions (meso-synoptic-intraseasonal) associated with monsoon onset over South China Sea (SCS) and its subsequent evolution. Results show that the monsoon onset (defined by development of steady wind direction and heavy precipitation) over the northern SCS occurred around May 15 -17. Prevailing southerlies and southwesterlies developed over the central SCS after May 20. Shortly after, monsoon convection developed over the whole SCS region around May 23-27. The entire onset process appeared to be delayed by about a week to 10 days compared with climatology. During late spring of 1998, mid-latitude frontal systems were particularly active. These systems strongly impacted the northern SCS convection and may have been instrumental in triggering the onset of the SCS monsoon. The Tropical Oceans and Global Atmosphere (TOGA) and Bureau of Meteorology Research Centre (BMRC) radar showed a wide variety of convective systems over the Intensive Flux Array, from frontal bands to shear-banded structure, deep convection, pop-corn type shallow convection, slow moving "fine lines" to water spout. Analysis of SSM/I wind and moisture data suggested that the delayed convective activity over the SCS may be linked to the weakened northward propagation of monsoon rain band, hence contributing to a persistence of the rainband south of the Yangtze River and the disastrous flood that occurred over this region during mid to late June, 1998.

  11. Nd isotopic composition and REE pattern in the surface waters of the eastern Indian Ocean and its adjacent seas

    SciTech Connect

    Amakawa, Hiroshi; Alibo, D.S.; Nozaki, Yoshiyuki

    2000-05-01

    The Nd isotopic composition and dissolved rare earth elements (REEs) have been measured in the surface waters along the 1996/97 R.V. Hakuho-Maru Expedition route from Tokyo to the Southern Ocean, southwest of Australia, through the Philippine and Indonesian Archipelago, the eastern Indian Ocean, the Bay of Bengal and the South China Sea. The radiogenic {epsilon}{sub Nd} values of {minus}1.3 and {minus}1.4 were found in the Sulu Sea and near the Lombok Strait, indicating the strong influence of surrounding volcanic islands, whereas non-radiogenic {epsilon}{sub Nd} values of less than {minus}10 were found in the Southern Ocean and the Bay of Bengal suggesting Nd of continental origin. The dissolved Nd concentrations also showed a wide range of variation from 2.8 to 19.6 pmol/kg and the trivalent REE patterns exhibited characteristic features that can be grouped into each different oceanic province. The geographical distribution of dissolved Nd is different from that of atmospherically derived {sup 210}Pb, but generally resembles that of coastally derived {sup 228}Ra. This strongly suggests that fluvial and coastal input predominates over eolian input for dissolved Nd in the surface ocean. However, the riverine dissolved Nd flux appears to be relatively minor, and remobilization of Nd from coastal and shelf sediments may play an important role in the total Nd input to the ocean. By modeling the distributions of the isotopic composition and concentration of Nd together with the activity ratio of {sup 228}Ra/{sup 226}Ra in the southeastern Indian Ocean, the authors estimate a mean residence time of Nd in the surface mixed layer to be 1.5--2.6 years. The short mean residence time is comparable with, or slightly longer than that of {sup 210}Pb suggesting similar chemical reactivity.

  12. Modeling sea-water intrusion with open boundary conditions

    SciTech Connect

    Padilla, F.; Cruz-Sanjulian, J.

    1997-07-01

    The present study concerns the application of a new numerical approach to describe the fresh-water/sea-water relationships in coastal aquifers. Essentially, a solution to the partial differential equation governing the regional motion of a phreatic surface and the resulting interface between fresh water and salt water is analyzed by a Galerkin finite-element formulation. A single-phase steady numerical model was applied to approximate, with simple triangular elements, the regional behavior of a coastal aquifer under appropriate sinks, sources, Neumann, outflow face, and open boundary conditions. On the one hand, outflow open boundaries at the coastline were not treated with other classical boundary conditions, but instead with a formal numerical approach for open boundaries inspired in this particular case by the Dupuit approximation of horizontal outflow at the boundary. The solution to this numerical model, together with the Ghyben-Herzberg principle, allows the correct simulation of fresh-water heads and the position of the salt-water interface for a steeply sloping coast. Although the solutions were precise and do not present classical numerical oscillations, this approach requires a previous solution with Dirichlet boundary conditions at the coastline in order to find a good convergence of the solution algorithm. On the other hand, the same precise results were obtained with a more restrictive open boundary condition, similar in a way to the outflow face approach, which required less computer time, did not need a prior numerical solution and could be extended to different coastline conditions. The steady-state problem was solved for different hypothetical coastal aquifers and fresh-water usage through three types of numerical tests.

  13. Diversity and distribution of eukaryotic microbes in and around a brine pool adjacent to the Thuwal cold seeps in the Red Sea.

    PubMed

    Wang, Yong; Zhang, Wei Peng; Cao, Hui Luo; Shek, Chun Shum; Tian, Ren Mao; Wong, Yue Him; Batang, Zenon; Al-Suwailem, Abdulaziz; Qian, Pei-Yuan

    2014-01-01

    A hypoxic/suboxic brine pool at a depth of about 850 m was discovered near the Thuwal cold seeps in the Red Sea. Filled with high concentrations of hydrogen sulfide and ammonia, such a brine pool might limit the spread of eukaryotic organisms. Here, we compared the communities of the eukaryotic microbes in a microbial mat, sediments and water samples distributed in 7 sites within and adjacent to the brine pool. Taxonomic classification of the pyrosequenced 18S rRNA amplicon reads showed that fungi highly similar to the species identified along the Arabic coast were almost ubiquitous in the water and sediment samples, supporting their wide distribution in various environments. The microbial mat displayed the highest species diversity and contained grazers and a considerable percentage of unclassified species. Phylogeny-based methods revealed novel lineages representing a majority of the reads from the interface between the sea water and brine pool. Phylogenetic relationships with more reference sequences suggest that the lineages were affiliated with novel Alveolata and Euglenozoa inhabiting the interface where chemosynthetic prokaryotes are highly proliferative due to the strong chemocline and halocline. The brine sediments harbored abundant species highly similar to invertebrate gregarine parasites identified in different oxygen-depleted sediments. Therefore, the present findings support the uniqueness of some microbial eukaryotic groups in this cold seep brine system. PMID:24575081

  14. Diversity and distribution of eukaryotic microbes in and around a brine pool adjacent to the Thuwal cold seeps in the Red Sea

    PubMed Central

    Wang, Yong; Zhang, Wei Peng; Cao, Hui Luo; Shek, Chun Shum; Tian, Ren Mao; Wong, Yue Him; Batang, Zenon; Al-Suwailem, Abdulaziz; Qian, Pei-Yuan

    2014-01-01

    A hypoxic/suboxic brine pool at a depth of about 850 m was discovered near the Thuwal cold seeps in the Red Sea. Filled with high concentrations of hydrogen sulfide and ammonia, such a brine pool might limit the spread of eukaryotic organisms. Here, we compared the communities of the eukaryotic microbes in a microbial mat, sediments and water samples distributed in 7 sites within and adjacent to the brine pool. Taxonomic classification of the pyrosequenced 18S rRNA amplicon reads showed that fungi highly similar to the species identified along the Arabic coast were almost ubiquitous in the water and sediment samples, supporting their wide distribution in various environments. The microbial mat displayed the highest species diversity and contained grazers and a considerable percentage of unclassified species. Phylogeny-based methods revealed novel lineages representing a majority of the reads from the interface between the sea water and brine pool. Phylogenetic relationships with more reference sequences suggest that the lineages were affiliated with novel Alveolata and Euglenozoa inhabiting the interface where chemosynthetic prokaryotes are highly proliferative due to the strong chemocline and halocline. The brine sediments harbored abundant species highly similar to invertebrate gregarine parasites identified in different oxygen-depleted sediments. Therefore, the present findings support the uniqueness of some microbial eukaryotic groups in this cold seep brine system. PMID:24575081

  15. Meiofauna assemblages of the Condor Seamount (North-East Atlantic Ocean) and adjacent deep-sea sediments

    NASA Astrophysics Data System (ADS)

    Zeppilli, Daniela; Bongiorni, Lucia; Cattaneo, Antonio; Danovaro, Roberto; Santos, Ricardo Serrão

    2013-12-01

    Seamounts are currently considered hotspots of biodiversity and biomass for macro- and megabenthic taxa, but knowledge of meiofauna is still limited. Studies have revealed the existence of highly diverse meiofauna assemblages; however most data are mainly qualitative or focused only on specific groups, thus preventing comparisons among seamounts and with other deep-sea areas. This study, conducted on Condor Seamount (Azores, North-East Atlantic Ocean), describes variation in abundance, biomass, community structure and biodiversity of benthic meiofauna from five sites located on the Condor Seamount: and one site away from the seamount. While the summit of the seamount hosted the highest alpha biodiversity, the flanks and the bases showed a rich meiofauna assemblage in terms of abundance and biomass. The observed marked differences in grain size composition of sediments reflected the oceanographic conditions impacting different sectors of the Condor seamount, and could play an important role in the spatial distribution of different meiofaunal taxa. Trophic conditions (biochemical composition of organic matter) explained 78% of the variability in the meiofauna biomass pattern while sediment grain influenced the vertical distribution of meiofauna and only partially explained meiofaunal taxa composition. This study provides a further advancement in the knowledge of meiofaunal communities of seamounts. Only a deeper understanding of the whole benthic communities (including meiofauna) will allow to elaborate effective management and conservation tools for seamount ecosystems.

  16. 90Sr dispersion and fate in the Northwestern Pacific and adjacent seas: global fallout and the Fukushima Dai-ichi accident

    NASA Astrophysics Data System (ADS)

    Jung, Kyung Tae; Maderich, Vladimir; Bezhenar, Roman; de With, Govert; Qiao, Fangli; Casacuberta, Nuria; Masque, Pere

    2014-05-01

    The 3D compartment model POSEIDON-R (Maderich et al., 2013) was applied to the Northwestern Pacific and adjacent seas to simulate the transport and fate of 90Sr in the period 1945-2010 and to perform a radiological assessment on the releases of 90Sr after the Fukushima Dai-ichi (FDNPP) accident (2011-2040). The model predicts the dispersion of radioactivity in the water column and in marine sediments, and the transfer of radionuclides throughout the marine food web, and the subsequent doses to the population due to the consumption of marine products. The contamination due to runoff of 90Sr from terrestrial surfaces was taken in account using generic predictive model (Smith et al., 2004). A dynamical food-chain model is used instead of the biological concentration factor (BCF) approach. The radionuclide uptake model for fish has as a central feature the accumulation of radionuclides in the target tissue (bones for 90Sr ). The model was compared with observation data on 90Sr for the period 1955-2010 and the budget of its activity was estimated. It was found that in the East China Sea and Yellow Sea the riverine influx was 1.5% of ocean influx only with local importance. Calculated concentrations of 90Sr in water, bottom sediments and marine organisms in the coastal box around the FDNPP before and after the accident are in agreement with measurements from the Japanese databases (TEPCO, MEXT) and publications (Casacuberta et al., 2013; Oikawa et al., 2013). The dynamical food web model predicts that due to the delay of the transfer throughout the food web and specific accumulation of 90Sr, the concentration for piscivorous fishes return to background level only in 2015. For the year 2011, the calculated individual dose rate for Fukushima Prefecture (except FDNPP vicinity) due to consumption of fishery products is an order less than the maximal dose rate caused by nuclear weapon testing in 1960.

  17. Habitat use and preferences of cetaceans along the continental slope and the adjacent pelagic waters in the western Ligurian Sea

    NASA Astrophysics Data System (ADS)

    Azzellino, A.; Gaspari, S.; Airoldi, S.; Nani, B.

    2008-03-01

    The physical habitat of cetaceans occurring along the continental slope in the western Ligurian Sea was investigated. Data were collected from two different sighting platforms, one of the two being a whale-watching boat. Surveys, conducted from May to October and from 1996 to 2000, covered an area of approximately 3000 km 2 with a mean effort of about 10,000 km year -1. A total of 814 sightings was reported, including all the species occurring in the area: Stenella coeruleoalba, Balaenoptera physalus, Physeter macrocephalus, Globicephala melas, Grampus griseus, Ziphius cavirostris, Tursiops truncatus, Delphinus delphis. A Geographic Information System was used to integrate sighting data to a set of environmental characteristics, which included bottom gradient, area between different isobaths, and length and linearity of the isobaths within a cell unit. Habitat use was analysed by means of a multi-dimensional scaling, MDS, analysis. Significant differences were found in the habitat preference of most of the species regularly occurring in the area. Bottlenose dolphin, Risso's dolphin, sperm whale and Cuvier's beaked whale were found strongly associated to well-defined depth and slope gradient characteristics of the shelf-edge and the upper and lower slope. The hypothesis of habitat segregation was considered for Risso's dolphin, sperm whale and Cuvier's beaked whale. Canonical discriminant functions using depth and slope as predictors outlined clear and not overlapping habitat preferences for Risso's dolphin and Cuvier's beaked whale, whereas a partial overlapping of the habitat of the other two species was observed for sperm whale. Such a partitioning of the upper and lower slope area may be the result of the common feeding habits and suggests a possible competition of these three species. A temporal segregation in the use of the slope area was also observed for sperm whales and Risso's dolphins. Fin whales, and the occasionally encountered common dolphin and long

  18. Spatial and temporal variations and controlling factors of sediment accumulation in the Yangtze River estuary and its adjacent sea area in the Holocene, especially in the Early Holocene

    NASA Astrophysics Data System (ADS)

    Feng, Zhibing; Liu, Baohua; Zhao, Yuexia; Li, Xishuang; Jiang, Li; Si, Shaokun

    2016-08-01

    The sub-bottom and collected borehole data provide insight into the transport and accumulation processes of the Yangtze-derived sediment in the study area since ~11 kyr BP. Five seismic units were identified according to six major acoustic surfaces. The sedimentary strata consist of fluvial, estuarine and deltaic systems from the bottom up, characterized by two different trends in sediment accumulation rates, i.e., low-high-low, and high-low-high. On the inner shelf of the East China Sea, the terrain with trough and ridge was formed by the Early Holocene transgression strata (formed in ~10 to 12 kyr BP) scoured by the later rectilinear tidal current due to postglacial sea-level transgression, and the sharply protruding seismic units are interpreted to be bedrocks outcropping on the seafloor. An analysis of the sedimentary characteristics in the boreholes and such factors as difference in accumulation rates, and tectonic subsidence led us to conclude that the paleo-coastline was located not far away from and to the east of Core ZK09 at ~9 kyr BP, and the southern bank of the Yangtze River estuary was located to the south of Core ZK09. At ~9 kyr, large volume of sediments was deposited in the northern isles of the Zhoushan archipelago and their adjacent bedrocks, forming a barrier effect on later sediment transport. During 7.5-8 kyr BP, the Yangtze-derived sediments were transported eastwards along the southern bank of the Yangtze River and the barrier due to the influence of the paleo-coastal current from the north, the direction of the Yangtze-derived sediment transport was split on the northeast of the Zhoushan archipelago, and the sediments covered the terrain with trough and ridge. During the high sea level period (7 kyr BP-present), the eastward migration of paleo-coastline had resulted in the increase in accumulation rate. We also conclude that the sharp increase in accumulation rate near the Yangtze River estuary after ~2 kyr BP was not primarily caused by

  19. Gaseous polycyclic aromatic hydrocarbon concentrations are higher in urban forests than adjacent open areas during summer but not in winter--Exploratory study.

    PubMed

    Viippola, Viljami; Rantalainen, Anna-Lea; Yli-Pelkonen, Vesa; Tervo, Peatta; Setälä, Heikki

    2016-01-01

    While the potential of plants to uptake polycyclic aromatic hydrocarbons (PAHs) is widely acknowledged, empirical evidence of the effects of this process on local atmospheric PAH concentrations and human health is tenuous. We measured gaseous PAH concentrations using passive samplers in urban tree-covered areas and adjacent open, treeless areas in a near-road environment in Finland to gain information on the ability of urban vegetation to improve air quality. The ability of urban, mostly deciduous, vegetation to affect PAHs was season dependent: during summer, concentrations were significantly higher in tree-covered areas, while in the fall, concentrations in open areas exceeded those in tree-covered areas. During winter, concentrations in tree-covered areas were either lower or did not differ from those in open areas. Results of this study imply that the commonly believed notion that trees unequivocally improve air quality does not apply to PAHs studied here. PMID:26412199

  20. [Spatial distribution and pollution assessment of heavy metals in the tidal reach and its adjacent sea estuary of Daliaohe area, China ].

    PubMed

    Zhang, Lei; Qin, Yan-wen; Ma, Ying-qun; Zhao, Yan-min; Shi, Yao

    2014-09-01

    The aim of this article was to explore the pollution level of heavy metals in the tidal reach and its adjacent sea estuary of Daliaohe area. The contents and spatial distribution of As, Cd, Cr, Cu, Ph and Zn in surface water, suspended solids and surface sediments were analyzed respectively. The integrated pollution index and geoaccumulation index were used to evaluate the contamination degree of heavy metals in surface water and surface sediments respectively. The results indicated that the contents of heavy metals in surface water was in the order of Pb < Cu < Cd < Cr < As < Zn. The heavy metal contents in surface water increased from river to sea. Compared with the contents of heavy metals in surface water of the typical domestic estuary in China, the overall contents of heavy metals in surface water were at a higher level. The contents of heavy metals in suspended solids was in the order of Cd < Cu < As < Cr

  1. Replacement of multiyear sea ice and changes in the open water season duration in the Beaufort Sea since 2004

    NASA Astrophysics Data System (ADS)

    Galley, R. J.; Babb, D.; Ogi, M.; Else, B. G. T.; Geilfus, N.-X.; Crabeck, O.; Barber, D. G.; Rysgaard, S.

    2016-03-01

    The last decade has witnessed the nine lowest Arctic September sea ice extents in the observational record. It also forms the most recent third of the long-term trend in that record, which reached -13.4% decade-1 in 2015. While hemispheric analyses paint a compelling picture of sea ice loss across the Arctic, the situation with multiyear ice in the Beaufort Sea is particularly dire. This study was undertaken in light of substantial changes that have occurred in the extent of summer multiyear sea ice in the Arctic inferred from the passive microwave record. To better elucidate these changes at a sub-regional scale, we use data from the Canadian Ice Service archive, the most direct observations of sea ice stage-of-development available. We also build upon the only previous sea ice climatological analysis for Canada's western Arctic region by sea ice stage-of-development that ended in 2004. The annual evolution of sea ice by stage of development in Canada's western Arctic changed dramatically between 1983 and 2014. The rate of these changes and their spatial prevalence were most prominent in the last decade. In summer, total sea ice loss occurred via reductions in old and first-year sea ice over increasingly large areas and over more months per year. Resultant delay of thermodynamic freeze up has increased the annual open water duration in the study region. The winter sea ice cover was increasingly composed of first-year sea ice at the expense of old ice. Breakup timing has not significantly changed in the region.

  2. Temporal trends of nonylphenol and bisphenol A contamination in the Pearl River Estuary and the adjacent South China Sea recorded by dated sedimentary cores.

    PubMed

    Peng, Xianzhi; Wang, Zhendi; Mai, Bixian; Chen, Fanrong; Chen, Shejun; Tan, Jianhua; Yu, Yiyi; Tang, Caiming; Li, Kechang; Zhang, Gan; Yang, Chun

    2007-10-01

    Three dated sedimentary cores were collected for the investigation of temporal trends and the environmental loadings of nonylphenol (NP) and bisphenol A (BPA) in recent decades in the Pearl River Estuary (PRE), South China and the adjacent South China Sea (SCS). The peak fluxes of NP and BPA occurred in the mid-1980s in the PRE, coincident with the rapid economic growth in China. The decline of NP and BPA fluxes is attributable to the implementation of sewage treatment in the late 1980s in the Pearl River Delta (PRD). Multi-model distributions were observed for the fluxes of NP and BPA in the SCS with the peak fluxes occurring in the late 1950s and the mid-1970s respectively. The fluxes of NP and BPA have increased since the 1990s due to the lack of adequate wastewater treatment facilities and the constant economic growth. Nonylphenol was quantifiably detected in sediments predating its widespread application (1940s), suggesting the downward penetration of NP in the sediment columns. The characterization results revealed that NP and BPA were preserved well and the isomer-selective degradation of NP did not occur significantly in the sediment cores. The environmental loadings of NP and BPA in the PRE sediments were roughly estimated to be 124 t and 1.7 t respectively over the past 30 years. PMID:17618676

  3. Regional long-term model of radioactivity dispersion and fate in the Northwestern Pacific and adjacent seas: application to the Fukushima Dai-ichi accident.

    PubMed

    Maderich, V; Bezhenar, R; Heling, R; de With, G; Jung, K T; Myoung, J G; Cho, Y-K; Qiao, F; Robertson, L

    2014-05-01

    The compartment model POSEIDON-R was modified and applied to the Northwestern Pacific and adjacent seas to simulate the transport and fate of radioactivity in the period 1945-2010, and to perform a radiological assessment on the releases of radioactivity due to the Fukushima Dai-ichi accident for the period 2011-2040. The model predicts the dispersion of radioactivity in the water column and in sediments, the transfer of radionuclides throughout the marine food web, and subsequent doses to humans due to the consumption of marine products. A generic predictive dynamic food-chain model is used instead of the biological concentration factor (BCF) approach. The radionuclide uptake model for fish has as a central feature the accumulation of radionuclides in the target tissue. The three layer structure of the water column makes it possible to describe the vertical structure of radioactivity in deep waters. In total 175 compartments cover the Northwestern Pacific, the East China and Yellow Seas and the East/Japan Sea. The model was validated from (137)Cs data for the period 1945-2010. Calculated concentrations of (137)Cs in water, bottom sediments and marine organisms in the coastal compartment, before and after the accident, are in close agreement with measurements from the Japanese agencies. The agreement for water is achieved when an additional continuous flux of 3.6 TBq y(-1) is used for underground leakage of contaminated water from the Fukushima Dai-ichi NPP, during the three years following the accident. The dynamic food web model predicts that due to the delay of the transfer throughout the food web, the concentration of (137)Cs for piscivorous fishes returns to background level only in 2016. For the year 2011, the calculated individual dose rate for Fukushima Prefecture due to consumption of fishery products is 3.6 μSv y(-1). Following the Fukushima Dai-ichi accident the collective dose due to ingestion of marine products for Japan increased in 2011 by a

  4. Exchanges between the open Black Sea and its North West shelf

    NASA Astrophysics Data System (ADS)

    Shapiro, Georgy; Wobus, Fred; Zhou, Feng

    2014-05-01

    Exchanges between the vast NW shelf and the deep basin of the Black Sea play a significant role in maintaining the balance of nutrients, heat content and salinity of the shelf waters. Nearly 87 % of the Black Sea is entirely anoxic below 70 to 200m and contains high levels of hydrogen sulphide (Zaitsev et al, 2001), and this makes the shelf waters particularly valuable for maintaining the Black Sea ecosystem in good health. The increase in salinity of shelf waters occurs partially due to exchanges with more saline open sea waters and represents a threat to relics and endemic species. The shelf-break is commonly considered the bottle-neck of the shelf-deep sea exchanges (e.g. (Huthnance, 1995, Ivanov et al, 1997). Due to conservation of potential vorticity, the geostrophic currents flow along the contours of constant depth. However the ageostrophic flows (Ekman drift, mesoscale eddies, filaments, internal waves) are not subject to the same constraints. It has been shown that during the winter well mixed cold waters formed on the North West shelf propagate into the deep sea, providing an important mechanism for the replenishment of the Cold Intermediate Layer ( Staneva and Stanev, 1997). However, much less is known about exchanges in the warm season. In this study, the transports of water, heat and salt between the northwestern shelf and the adjacent deep basin of the Black Sea are investigated using a high-resolution three-dimensional primitive equation model, NEMO-SHELF-BLS (Shapiro et al, 2013). It is shown that during the period from April to August, 2005, both onshore and offshore cross-shelf break transports in the top 20 m were as high as 0.24 Sv on average, which was equivalent to the replacement of 60% of the volume of surface shelf waters (0 - 20 m) per month. Two main exchange mechanisms are studied: (i) Ekman transport, and (ii) transport by mesoscale eddies and associated meanders of the Rim Current. The Ekman drift causes nearly uniform onshore or

  5. The impact of variations in oceanographic conditions on distribution of redfish in the Irminger Sea and adjacent waters - the temperature is as major factor such cause according to analysis of climatic variability and SST Satellite Data

    NASA Astrophysics Data System (ADS)

    Vanyushin, Georgy; Melnikov, Sergey; Bulatova, Tatiana; Krovnin, Andrey; Troshkov, Anatoly

    2016-04-01

    In this study, for the first time, the data of satellite ("NOAA" and "Meteosat") monitoring of the Irminger Sea and adjacent waters were used to estimate the impact of the Sea surface temperature (SST) on distribution and density of redfish concentrations. We made analytical calculations of the average values of SST for the reference zone of the Irminger Sea, integral acoustic values (SA) for the reference zone, and the average values of the SA only for those sites on the reference zone where redfish were found in the layer 0-500 m. The strong correlation between SST and average values of redfish density for real situations shows that the lower SST values correspond to the lower integral and average values of redfish density. The area of the Irminger Sea and adjacent waters is characterized by considerable interannual and decadal climatic variability associated with the state of the NAO (the North Atlantic Oscillation) and phase of the AMO (the Atlantic Multidecadal Oscillation). This results in corresponding variations of the thermal parameters in the upper 500-m layer. The further investigations are needed to identify mechanisms of transfer of physical anomalies controlled by the NAO and AMO, from the sea surface into the intermediate and deep layers of water column. The climatic variability leads to permanent spatial redistribution of redfish concentrations. The results obtained confirm that environmental processes, rather than fishery, have the greater impact on estimates of redfish distribution. Key words: satellite monitoring of SST, climatic variability, the North Atlantic, the Irminger Sea, redfish distribution.

  6. Spatiotemporal Distribution, Sources, and Photobleaching Imprint of Dissolved Organic Matter in the Yangtze Estuary and Its Adjacent Sea Using Fluorescence and Parallel Factor Analysis

    PubMed Central

    Li, Penghui; Chen, Ling; Zhang, Wen; Huang, Qinghui

    2015-01-01

    To investigate the seasonal and interannual dynamics of dissolved organic matter (DOM) in the Yangtze Estuary, surface and bottom water samples in the Yangtze Estuary and its adjacent sea were collected and characterized using fluorescence excitation-emission matrices (EEMs) and parallel factor analysis (PARAFAC) in both dry and wet seasons in 2012 and 2013. Two protein-like components and three humic-like components were identified. Three humic-like components decreased linearly with increasing salinity (r>0.90, p<0.001), suggesting their distribution could primarily be controlled by physical mixing. By contrast, two protein-like components fell below the theoretical mixing line, largely due to microbial degradation and removal during mixing. Higher concentrations of humic-like components found in 2012 could be attributed to higher freshwater discharge relative to 2013. There was a lack of systematic patterns for three humic-like components between seasons and years, probably due to variations of other factors such as sources and characteristics. Highest concentrations of fluorescent components, observed in estuarine turbidity maximum (ETM) region, could be attributed to sediment resuspension and subsequent release of DOM, supported by higher concentrations of fluorescent components in bottom water than in surface water at two stations where sediments probably resuspended. Meanwhile, photobleaching could be reflected from the changes in the ratios between fluorescence intensity (Fmax) of humic-like components and chromophoric DOM (CDOM) absorption coefficient (a355) along the salinity gradient. This study demonstrates the abundance and composition of DOM in estuaries are controlled not only by hydrological conditions, but also by its sources, characteristics and related estuarine biogeochemical processes. PMID:26107640

  7. Space-time dynamics of carbon and environmental parameters related to carbon dioxide emissions in the Buor-Khaya Bay and adjacent part of the Laptev Sea

    NASA Astrophysics Data System (ADS)

    Semiletov, I. P.; Shakhova, N. E.; Pipko, I. I.; Pugach, S. P.; Charkin, A. N.; Dudarev, O. V.; Kosmach, D. A.; Nishino, S.

    2013-09-01

    This study aims to improve understanding of carbon cycling in the Buor-Khaya Bay (BKB) and adjacent part of the Laptev Sea by studying the inter-annual, seasonal, and meso-scale variability of carbon and related hydrological and biogeochemical parameters in the water, as well as factors controlling carbon dioxide (CO2) emission. Here we present data sets obtained on summer cruises and winter expeditions during 12 yr of investigation. Based on data analysis, we suggest that in the heterotrophic BKB area, input of terrestrially borne organic carbon (OC) varies seasonally and inter-annually and is largely determined by rates of coastal erosion and river discharge. Two different BKB sedimentation regimes were revealed: Type 1 (erosion accumulation) and Type 2 (accumulation). A Type 1 sedimentation regime occurs more often and is believed to be the quantitatively most important mechanism for suspended particular matter (SPM) and particulate organic carbon (POC) delivery to the BKB. The mean SPM concentration observed in the BKB under a Type 1 regime was one order of magnitude greater than the mean concentration of SPM (~ 20 mg L-1) observed along the Lena River stream in summer 2003. Loadings of the BKB water column with particulate material vary by more than a factor of two between the two regimes. Higher partial pressure of CO2 (pCO2), higher concentrations of nutrients, and lower levels of oxygen saturation were observed in the bottom water near the eroded coasts, implying that coastal erosion and subsequent oxidation of eroded organic matter (OM) rather than the Lena River serves as the predominant source of nutrients to the BKB. Atmospheric CO2 fluxes from the sea surface in the BKB vary from 1 to 95 mmol m-2 day-1 and are determined by specific features of hydrology and wind conditions, which change spatially, seasonally, and inter-annually. Mean values of CO2 emission from the shallow Laptev Sea were similar in September 1999 and 2005 (7.2 and 7.8 mmol m-2 day-1

  8. Mantle flow beneath Arabia offset from the opening Red Sea

    NASA Astrophysics Data System (ADS)

    Chang, Sung-Joon; Merino, Miguel; Van der Lee, Suzan; Stein, Seth; Stein, Carol A.

    2011-02-01

    Continental rifting involves a poorly understood sequence of lithospheric stretching, volcanism, and mantle flow that evolves to seafloor spreading. We present new insight from inversion of seismic traveltimes and waveforms beneath Arabia and surroundings. Low velocities occur beneath the southern Red Sea and Gulf of Aden, consistent with active spreading. However, hot material extends not below the northern Red Sea, but is offset eastward beneath Arabia, showing mantle flow from the Afar hotspot. The location of this channel beneath volcanic rocks erupted since rifting began 30 million years ago indicates that flow moves with Arabia. We propose that the absence of seafloor spreading in the northern Red Sea reflects the offset flow. This geometry may evolve to spreading in the Northern Red Sea, rifting of Arabia, or both. This situation has aspects of both active and passive rifting, showing that both can occur before coalescing to seafloor spreading.

  9. Spatial-Temporal Variations of Chlorophyll-a in the Adjacent Sea Area of the Yangtze River Estuary Influenced by Yangtze River Discharge

    PubMed Central

    Wang, Ying; Jiang, Hong; Jin, Jiaxin; Zhang, Xiuying; Lu, Xuehe; Wang, Yueqi

    2015-01-01

    Carrying abundant nutrition, terrigenous freshwater has a great impact on the spatial and temporal heterogeneity of phytoplankton in coastal waters. The present study analyzed the spatial-temporal variations of Chlorophyll-a (Chl-a) concentration under the influence of discharge from the Yangtze River, based on remotely sensed Chl-a concentrations. The study area was initially zoned to quantitatively investigate the spatial variation patterns of Chl-a. Then, the temporal variation of Chl-a in each zone was simulated by a sinusoidal curve model. The results showed that in the inshore waters, the terrigenous discharge was the predominant driving force determining the pattern of Chl-a, which brings the risk of red tide disasters; while in the open sea areas, Chl-a was mainly affected by meteorological factors. Furthermore, a diversity of spatial and temporal variations of Chl-a existed based on the degree of influences from discharge. The diluted water extended from inshore to the east of Jeju Island. This process affected the Chl-a concentration flowing through the area, and had a potential impact on the marine environment. The Chl-a from September to November showed an obvious response to the discharge from July to September with a lag of 1 to 2 months. PMID:26006121

  10. Spatial-Temporal Variations of Chlorophyll-a in the Adjacent Sea Area of the Yangtze River Estuary Influenced by Yangtze River Discharge.

    PubMed

    Wang, Ying; Jiang, Hong; Jin, Jiaxin; Zhang, Xiuying; Lu, Xuehe; Wang, Yueqi

    2015-05-01

    Carrying abundant nutrition, terrigenous freshwater has a great impact on the spatial and temporal heterogeneity of phytoplankton in coastal waters. The present study analyzed the spatial-temporal variations of Chlorophyll-a (Chl-a) concentration under the influence of discharge from the Yangtze River, based on remotely sensed Chl-a concentrations. The study area was initially zoned to quantitatively investigate the spatial variation patterns of Chl-a. Then, the temporal variation of Chl-a in each zone was simulated by a sinusoidal curve model. The results showed that in the inshore waters, the terrigenous discharge was the predominant driving force determining the pattern of Chl-a, which brings the risk of red tide disasters; while in the open sea areas, Chl-a was mainly affected by meteorological factors. Furthermore, a diversity of spatial and temporal variations of Chl-a existed based on the degree of influences from discharge. The diluted water extended from inshore to the east of Jeju Island. This process affected the Chl-a concentration flowing through the area, and had a potential impact on the marine environment. The Chl-a from September to November showed an obvious response to the discharge from July to September with a lag of 1 to 2 months. PMID:26006121

  11. Mantle Flow beneath Arabia Offset from the Opening Red Sea

    NASA Astrophysics Data System (ADS)

    Stein, S. A.; Chang, S.; Merino, M.; van der Lee, S.; Stein, C. A.

    2010-12-01

    The rifting of continents involves a complex and poorly understood sequence of lithospheric stretching, volcanism, and mantle flow that eventually gives rise to seafloor spreading that forms a new ocean basin. The Red Sea, forming as the Arabian plate diverges from Africa, is a classic area for studying this process. Here, we present new insight from joint inversion of seismic wave travel times and waveforms to map velocity structure beneath Arabia and its surroundings. We find the low velocities expected for hot upwelling mantle material centered beneath the southern Red Sea and Gulf of Aden, consistent with the active spreading there. However, this hot material extends not below the northern Red Sea, but is instead offset to the east beneath Arabia, showing northward upper mantle flow from the Afar hotspot. The location of this low velocity channel beneath volcanic rocks erupted since rifting began 30 million years ago indicates that although the flow originates from the hotspot that is essentially fixed in the upper mantle, the channel moves with the Arabian plate. We thus propose that the absence of seafloor spreading in the northern Red Sea reflects the offset mantle flow. Because this offset has existed for millions of years, it is unclear whether it will evolve into seafloor spreading, rifting of Arabia above the channel, or both. This situation has aspects of the end-member models of rifting initiated by either mantle flow or lithospheric extension, and thus shows that the two can occur somewhat independently in different places before coalescing to seafloor spreading.

  12. The Art of Open Spaces: Contemporary Sea and Prairiescapes

    ERIC Educational Resources Information Center

    Schultz, Elizabeth

    2007-01-01

    The number of contemporary Kansas prairie artists whose works project an affinity for the sea continues to grow. This article focuses on six in particular: painters Robert Sudlow, Keith Jacobshagen, Lisa Grossman, and Louis Copt, and photographers Terry Evans and Larry Schwarm. Each of these Kansas-connected prairie artists has exhibited…

  13. Copper in the sediment and sea surface microlayer near a fallowed, open-net fish farm.

    PubMed

    Loucks, Ronald H; Smith, Ruth E; Fisher, Clyde V; Fisher, E Brian

    2012-09-01

    Sediment and sea surface microlayer samples near an open-net salmon farm in Nova Scotia, were analysed for copper. Copper is a constituent of the feed and is an active ingredient of anti-foulants. The salmon farm was placed in fallow after 15 years of production. Sampling was pursued over 27 months. Elevated copper concentrations in the sediments indicated the farm site as a source. Bubble flotation due to gas-emitting sediments from eutrophication is a likely process for accumulating copper in the sea surface microlayer at enriched concentrations. Elevated and enriched concentrations in the sea surface microlayer over distance from the farm site led, as a result of wind-drift, to an enlarged farm footprint. The levels of copper in both sediments and sea surface microlayer exceeded guidelines for protection of marine life. Over the 27 months period, copper levels persisted in the sediments and decreased gradually in the sea surface microlayer. PMID:22704150

  14. A combined radiative transfer model for sea ice, open ocean, and atmosphere

    NASA Astrophysics Data System (ADS)

    Fuhrhop, Rolf; Grenfell, Thomas C.; Heygster, Georg; Johnsen, Klaus-Peter; Schlüssel, Peter; Schrader, Meeno; Simmer, Clemens

    1998-03-01

    A radiative transfer model to compute brightness temperatures in the microwave frequency range for polar regions including sea ice, open ocean, and atmosphere has been developed and applied to sensitivity studies and retrieval algorithm development. The radiative transfer within sea ice is incorporated according to the "many layer strong fluctuation theory" of Stogryn [1986, 1987] and T. Grenfell [Winebrenner et al., 1992]. The reflectivity of the open water is computed with the three-scale model of Schrader [1995]. Both surface models supply the bistatic scattering coefficients, which define the lower boundary for the atmospheric model. The atmospheric model computes the gaseous absorption by the Liebe et al. [1993] model. Scattering by hydrometeors is determined by Mie or Rayleigh theory. Simulated brightness temperatures have been compared with special sensor microwave imager (SSM/I) observations. The comparison exhibits shortcomings of the ice model for 37 GHz. Applying a simple ad hoc correction at this frequency gives consistent comparison results within the range of observational accuracy. The simulated brightness temperatures show the strong influence of clouds and variations of wind speed over the open ocean, which will affect the sea ice retrieval even for an ice-covered ocean. Simulated brightness temperatures have been used to train a neural network algorithm for the total sea ice concentration, which accounts for these effects. Sea ice concentrations sensed from the SSM/I data using the network and the NASA sea ice algorithm show systematic differences in dependence on cloudiness.

  15. Sedimentation in the western Arabian Sea the role of coastal and open-ocean upwelling

    NASA Astrophysics Data System (ADS)

    Rixen, Tim; Haake, Birgit; Ittekkot, Venugopalan

    Monsoon-induced coastal and open-ocean upwelling explain 84% of the variations of the organic carbon fluxes measured in the deep western Arabian Sea. In this paper, sea-level measurements, satellite-derived wind speeds, sea surface temperatures, and nutrient profiles are used to discern the relative importance of these factors on fluxes measured during nine years of continuous sediment trap deployments. This exercise shows: (i) the increase in fluxes observed during the initial stages of the SW monsoons are caused by open-ocean upwelling, which develops faster than the coastal upwelling; (ii) coastal upwelling triggers diatom blooms from nutrients from subsurface water and sediment resuspension and, more importantly, by injecting resting stages of diatoms back into the euphotic zone; (iii) silica depletion resulting from diatom blooms in laterally advecting water masses leads to a replacement of diatoms by other nitrate-limited organisms; (iv) organic carbon fluxes to the deep Arabian Sea increase in response to an intensification of both coastal and open-ocean upwelling; weak coastal upwelling and strong open-ocean upwelling also increase organic carbon fluxes. The varying dominance of their influence is reflected in the timing and the composition of the peak fluxes; (v) the link between organic carbon flux and monsoon strength is non-linear probably due to changes in the surface currents and to vigorous turbulence in the surface water during strong SW monsoons. These processes could reduce the organic carbon flux in the western Arabian Sea by about 65%.

  16. Large scale distribution of dioxins, PCBs, heavy metals, PAH-metabolites and radionuclides in cod (Gadus morhua) from the North Atlantic and its adjacent seas.

    PubMed

    Karl, Horst; Kammann, Ulrike; Aust, Marc-Oliver; Manthey-Karl, Monika; Lüth, Anja; Kanisch, Günter

    2016-04-01

    Regarding cod as sea food for human consumption and as bio indicator of the marine eco system, this study is the first approach to combine the analysis of organic and inorganic contaminants and radionuclides in cod muscle as well as PCDD/Fs and dl-PCBs in its livers from the same fishing areas. Concentrations of 1-hydroxypyrene, PCDD/Fs, PCBs, cesium-137 (Cs-137), cadmium and lead were determined in individual or pooled samples over a wide geographic area, including Greenland Seas, Barents Sea, North and Baltic Sea. Highest concentrations were found in samples from the Baltic Sea, lowest in the pristine areas of the Barents Sea and Greenland. Levels of contaminants in cod muscle were found to be far below the established EU maximum levels (ML), regardless of which fishing grounds. In contrast to this, most cod liver samples from the North and Baltic Sea showed PCDD/F and PCB contents exceeding the ML. In addition, new background assessment criteria (BAC) for 1-hydroxypyrene in cod of 4.6 ng mL(-1) bile and for Cs-137 a BAC of 0.16 Bq kg(-1) wet weight are proposed to be included in the European Marine Strategy Framework Directive for cod from the Northeast Atlantic. PMID:26874057

  17. Open-system coral ages reveal persistent suborbital sea-level cycles.

    PubMed

    Thompson, William G; Goldstein, Steven L

    2005-04-15

    Sea level is a sensitive index of global climate that has been linked to Earth's orbital variations, with a minimum periodicity of about 21,000 years. Although there is ample evidence for climate oscillations that are too frequent to be explained by orbital forcing, suborbital-frequency sea-level change has been difficult to resolve, primarily because of problems with uranium/thorium coral dating. Here we use a new approach that corrects coral ages for the frequently observed open-system behavior of uranium-series nuclides, substantially improving the resolution of sea-level reconstruction. This curve reveals persistent sea-level oscillations that are too frequent to be explained exclusively by orbital forcing. PMID:15831756

  18. Open-System Coral Ages Reveal Persistent Suborbital Sea-Level Cycles

    NASA Astrophysics Data System (ADS)

    Thompson, William G.; Goldstein, Steven L.

    2005-04-01

    Sea level is a sensitive index of global climate that has been linked to Earth's orbital variations, with a minimum periodicity of about 21,000 years. Although there is ample evidence for climate oscillations that are too frequent to be explained by orbital forcing, suborbital-frequency sea-level change has been difficult to resolve, primarily because of problems with uranium/thorium coral dating. Here we use a new approach that corrects coral ages for the frequently observed open-system behavior of uranium-series nuclides, substantially improving the resolution of sea-level reconstruction. This curve reveals persistent sea-level oscillations that are too frequent to be explained exclusively by orbital forcing.

  19. Plankton in the open Mediterranean Sea: a review

    NASA Astrophysics Data System (ADS)

    Siokou-Frangou, I.; Christaki, U.; Mazzocchi, M. G.; Montresor, M.; Ribera D'Alcalá, M.; Vaqué, D.; Zingone, A.

    2009-11-01

    We present an overview of the plankton studies conducted during the last 25 years in the epipelagic offshore waters of the Mediterranean Sea. This quasi-enclosed sea is characterized by a rich and complex physical dynamics that includes unique thermohaline features, particular multilayer circulation, topographic gyres, and meso- and sub-mesoscale activity. Recent investigations have basically confirmed the long-recognised oligotrophic character of this sea, which enhances along both the west-east, and the north-south directions. Nutrient availability is low, especially for phosphorous (N:P up to 60), although limitation may be relaxed by inputs from highly populated coasts and from the atmosphere. Phytoplankton biomass as chl-a, generally displays low values (less than 0.2 μg chl-a l-1) over large areas, with a modest late winter increase. A large bloom (up to 3 μg l-1) throughout the late winter and early spring is only observed in the NW area. Relatively high biomass peaks are also recorded in fronts and cyclonic gyres. A deep chlorophyll maximum is a~permanent feature for the whole basin (except during the late winter mixing). It progressively deepens from the Alboran Sea (30 m) to the easternmost Levantine basin (120 m). Primary production reveals a similar west-east decreasing trend and ranges from 59 to 150 g C m-2 y-1 (in situ measurements). Overall the basin is largely dominated by small-sized autotrophs, microheterotrophs and egg-carrying copepod species. The phytoplankton, the microbial (both autotrophic and heterotrophic) and the zooplankton components reveal a considerable diversity and variability over spatial and temporal scales, the latter less explored though. Examples are the wide diversity of dinoflagellates and coccolithophores, the multifarious role of diatoms or picoeukaryotes, and the distinct seasonal or spatial patterns of the species-reach copepod genera or families which dominate in the basin. Major dissimilarities between western and

  20. Plankton in the open Mediterranean Sea: a review

    NASA Astrophysics Data System (ADS)

    Siokou-Frangou, I.; Christaki, U.; Mazzocchi, M. G.; Montresor, M.; Ribera D'Alcalá, M.; Vaqué, D.; Zingone, A.

    2010-05-01

    We present an overview of the plankton studies conducted during the last 25 years in the epipelagic offshore waters of the Mediterranean Sea. This quasi-enclosed sea is characterized by a rich and complex physical dynamics with distinctive traits, especially in regard to the thermohaline circulation. Recent investigations have basically confirmed the long-recognised oligotrophic nature of this sea, which increases along both the west-east and the north-south directions. Nutrient availability is low, especially for phosphorous (N:P up to 60), though this limitation may be buffered by inputs from highly populated coasts and from the atmosphere. Phytoplankton biomass, as chl a, generally displays low values (less than 0.2 μg chl a l-1) over large areas, with a modest late winter increase. A large bloom (up to 3 μg l-1) is observed throughout the late winter and spring exclusively in the NW area. Relatively high biomass values are recorded in fronts and cyclonic gyres. A deep chlorophyll maximum is a permanent feature for the whole basin, except during the late winter mixing. It is found at increasingly greater depths ranging from 30 m in the Alboran Sea to 120 m in the easternmost Levantine basin. Primary production reveals a west-east decreasing trend and ranges between 59 and 150 g C m-2 y-1 (in situ measurements). Overall, the basin is largely dominated by small autotrophs, microheterotrophs and egg-carrying copepod species. The microorganisms (phytoplankton, viruses, bacteria, flagellates and ciliates) and zooplankton components reveal a considerable diversity and variability over spatial and temporal scales, although the latter is poorly studied. Examples are the wide diversity of dinoflagellates and coccolithophores, the multifarious role of diatoms or picoeukaryotes, and the distinct seasonal or spatial patterns of the species-rich copepod genera or families which dominate the basin. Major dissimilarities between western and eastern basins have been

  1. Freshwater mass balance and exchange of water masses with the open sea: the Mljet Lakes (Croatia, Adriatic Sea)

    NASA Astrophysics Data System (ADS)

    Martincic, Urska; Bezak, Nejc; Zagar, Dusan; Makovec, Tihomir; Lucic, Davor; Onofri, Vladimir; Malacic, Vlado

    2016-04-01

    Two karstic seawater lakes (Veliko - Big and Malo - Small Lake) located in the National Park Mljet on the Mljet Island in Croatia were investigated in this study. The Small and the Big Lake cover 0.25 and 1.45 km2, respectively. The two lakes are connected to each other and to the sea by narrow channels. The connecting channel between the Big Lake and the sea is 12 m wide and 3 m deep. The connection to the Small Lake leads through another artificial channel (2.7 m wide and 0.8 m deep). The average salinity of the Big and the Small lake is 37.75 and 36.9, respectively, and the average salinity of the open sea is 38.5. While previous studies have been conducted due to the lakes' unique ecosystem and the karstic characteristics of the area, the main aim of this study was to determine the freshwater mass balance and exchange of water masses with the nearby sea. Several measurement campaigns were performed between 2008 and 2015 when meteorological parameters as well as salinity, water temperature and water velocities in both lakes and the channels were observed. A perpetual year was determined using available meteorological data. The contribution of the surface runoff to both lakes was modelled using the hydrological rainfall-runoff HEC-HMS model. Curve number parameter was estimated using the CLC Corine Land cover and geomorphological maps. Evaporation from the lake was calculated using the Verburg, Kondo and Coare equations. We found that the annual evaporation approximately equals the annual rainfall to the lake surface (cca. 550-600 mm). From the hydrological model and the difference between precipitation and evaporation from the lake surface we calculated the annual net excess of freshwater between 0.5 106 and 0.7 106 m3. The average salinity in both lakes is lower than the salinity in the sea; therefore, we hypothesize that the excess water should be discharged either through the channel between the Big Lake and the open sea or through underwater karstic sink

  2. Did opening of the South China Sea impact development of the Asian Monsoon? Results from Oligocene microfossils, IODP Site U1435, northern South China Sea

    NASA Astrophysics Data System (ADS)

    Kulhanek, Denise K.; Su, Xin; Li, Qianyu; Gregory, Mitch; Warny, Sophie; Clift, Peter D.

    2016-04-01

    Development of the Asian Monsoon is linked to uplift of the Himalayas and Tibetan Plateau in the Cenozoic, with good evidence for a strong monsoon system by the late Oligocene to early Miocene (e.g., Guo et al., 2002; Clift et al., 2008). However, Licht et al. (2014) suggested the presence of an Asian Monsoon in the late Eocene. Recent scientific ocean drilling in the Indian Ocean and surrounding marginal seas gives us the opportunity to test this hypothesis with newly recovered Paleogene sediment cores. International Ocean Discovery Program Expedition 349 to the South China Sea recovered a 30 m section of primarily lower Oligocene nannofossil-rich claystone at Site U1435, located near the northern continent/ocean boundary. A thick sandstone unit devoid of typical marine microfossils underlies the marine claystone. The sandstone is interpreted as a deltaic or restricted marine deposit and is dated to the Eocene based on the presence of organic-walled palynomorphs, suggesting that a hiatus of several million years likely separates the sandstone below from the Oligocene marine claystone. This hiatus is interpreted as the breakup unconformity, with paleodepths in the South China Sea increasing during the Oligocene. Thus, this claystone should record if opening of the South China Sea during the early Oligocene influenced development of the Asian Monsoon. Combined calcareous nannofossil and planktonic foraminifer biostratigraphy indicates that the 30 m section is primarily early Oligocene in age (~33.5-30 Ma) and was deposited on the middle slope, with paleodepths >500 m. Stable oxygen isotopes from planktonic foraminifers become heavier up-hole, suggestive of cooling/deepening in the region, whereas carbon isotopes record variable conditions with no distinct maxima or minima. Calcareous nannoplankton primarily live in the upper 50 m of the ocean and are sensitive to sea-surface temperature and nutrient conditions, thus making them useful recorders of paleoceanographic

  3. A-type granite and the Red Sea opening

    USGS Publications Warehouse

    Coleman, R.G.; DeBari, S.; Peterman, Z.

    1992-01-01

    Miocene-Oligocene A-type granite intrudes the eastern side of the Red Sea margin within the zone of extension from Jiddah, Saudi Arabia south to Yemen. The intrusions developed in the early stages of continental extension as Arabia began to move slowly away from Africa (around 30-20 Ma). Within the narrow zone of extension silicic magmas formed dikes, sills, small plutons and extrusive equivalents. In the Jabal Tirf area of Saudi Arabia these rocks occur in an elongate zone consisting of late Precambrian basement to the east, which is gradually invaded by mafic dikes. The number of dikes increases westward until an igneous complex is produced parallel to the present Red Sea axis. The Jabal Tirf igneous complex consists of diabase and rhyolite-granophyre sills (20-24 Ma). Although these are intrusine intrusive rocks their textures indicate shallow depths of intrusion (< 1 km). To the south, in the Yemen, contemporaneous with alkali basaltic eruptions (26-30 Ma) and later silicic eruptions, small plutons, dikes, and stocks of alkali granite invaded thick (1500 m) volcanic series, at various levels and times. Erosion within the uplifted margin of Yemen suggests that the maximum depth of intrusion was less than 1-2 km. Granophyric intrusions (20-30 Ma) within mafic dike swarms similar to the Jabal Tirf complex are present along the western edge of the Yemen volcanic plateau, marking a north-south zone of continental extension. The alkali granites of Yemen consist primarily of perthitic feldspar and quartz with some minor alkali amphiboles and acmite. These granites represent water-poor, hypersolvus magmas generated from parent alkali basalt magmas. The granophyric, two-feldspar granites associated with the mafic dike swarms and layered gabbros formed by fractional crystallization from tholeiitic basalt parent developed in the early stages of extension. Initial 87Sr/86Sr ratios of these rocks and their bulk chemistry indicate that production of peralkaline and

  4. Organophosphate ester (OPE) flame retardants and plasticizers in the open Mediterranean and Black Seas atmosphere.

    PubMed

    Castro-Jiménez, Javier; Berrojalbiz, Naiara; Pizarro, Mariana; Dachs, Jordi

    2014-03-18

    The presence of organophosphate ester (OPE) flame retardants and plasticizers has been confirmed for the first time in the atmosphere over the Mediterranean and Black Seas. Atmospheric aerosol samples were collected during two West-East oceanographic cruises across the Mediterranean and in the southwest Black Sea. This comprehensive assessment of baseline concentrations of aerosol phase OPEs, spatial distribution, and related deposition fluxes reveals levels ranging from 0.4 to 6.0 ng m(-3) for the ∑14OPEs and a lack of significant differences among sub-basins. Levels measured across the Mediterranean Sea and in the Black Sea are in the upper range or higher than those from previous reports for the marine atmosphere, presumably due to proximity to sources. From 13 to 260 tons of OPEs are estimated to be annually loaded to the Mediterranean Sea open waters from the atmosphere. Tris-(1-chloro-2-propyl)phosphate (TCPP) was the most abundant compound over the atmosphere of all the Mediterranean and Black Sea sub-basins, and therefore the chemical reaching surface waters at a higher extent by dry deposition. The atmospheric deposition fluxes of phosphorus due to OPE deposition is a significant fraction of known atmospheric inputs of new organic phosphorus (P), suggesting the relevant role that anthropogenic organic pollutants could play in the P cycle. PMID:24564832

  5. Contrasting sea-ice and open-water boundary layers during melt and freeze-up seasons: Some result from the Arctic Clouds in Summer Experiment.

    NASA Astrophysics Data System (ADS)

    Tjernström, Michael; Sotiropoulou, Georgia; Sedlar, Joseph; Achtert, Peggy; Brooks, Barbara; Brooks, Ian; Persson, Ola; Prytherch, John; Salsbury, Dominic; Shupe, Matthew; Johnston, Paul; Wolfe, Dan

    2016-04-01

    With more open water present in the Arctic summer, an understanding of atmospheric processes over open-water and sea-ice surfaces as summer turns into autumn and ice starts forming becomes increasingly important. The Arctic Clouds in Summer Experiment (ACSE) was conducted in a mix of open water and sea ice in the eastern Arctic along the Siberian shelf during late summer and early autumn 2014, providing detailed observations of the seasonal transition, from melt to freeze. Measurements were taken over both ice-free and ice-covered surfaces, offering an insight to the role of the surface state in shaping the lower troposphere and the boundary-layer conditions as summer turned into autumn. During summer, strong surface inversions persisted over sea ice, while well-mixed boundary layers capped by elevated inversions were frequent over open-water. The former were often associated with advection of warm air from adjacent open-water or land surfaces, whereas the latter were due to a positive buoyancy flux from the warm ocean surface. Fog and stratus clouds often persisted over the ice, whereas low-level liquid-water clouds developed over open water. These differences largely disappeared in autumn, when mixed-phase clouds capped by elevated inversions dominated in both ice-free and ice-covered conditions. Low-level-jets occurred ~20-25% of the time in both seasons. The observations indicate that these jets were typically initiated at air-mass boundaries or along the ice edge in autumn, while in summer they appeared to be inertial oscillations initiated by partial frictional decoupling as warm air was advected in over the sea ice. The start of the autumn season was related to an abrupt change in atmospheric conditions, rather than to the gradual change in solar radiation. The autumn onset appeared as a rapid cooling of the whole atmosphere and the freeze up followed as the warm surface lost heat to the atmosphere. While the surface type had a pronounced impact on boundary

  6. Spatial and temporal variations and controlling factors of sediment accumulation in the Yangtze River estuary and its adjacent sea area in the Holocene, especially in the Early Holocene

    NASA Astrophysics Data System (ADS)

    Feng, Zhibing; Liu, Baohua; Zhao, Yuexia; Li, Xishuang; Jiang, Li; Si, Shaokun

    2016-08-01

    The sub-bottom and collected borehole data provide insight into the transport and accumulation processes of the Yangtze-derived sediment in the study area since ~11 kyr BP. Five seismic units were identified according to six major acoustic surfaces. The sedimentary strata consist of fluvial, estuarine and deltaic systems from the bottom up, characterized by two different trends in sediment accumulation rates, i.e., low-high-low, and high-low-high. On the inner shelf of the East China Sea, the terrain with trough and ridge was formed by the Early Holocene transgression strata (formed in ~10 to 12 kyr BP) scoured by the later rectilinear tidal current due to postglacial sea-level transgression, and the sharply protruding seismic units are interpreted to be bedrocks outcropping on the seafloor. An analysis of the sedimentary characteristics in the boreholes and such factors as difference in accumulation rates, and tectonic subsidence led us to conclude that the paleo-coastline was located not far away from and to the east of Core ZK09 at ~9 kyr BP, and the southern bank of the Yangtze River estuary was located to the south of Core ZK09. At ~9 kyr BP, the Yangtze-derived sediments were transported eastwards along the southern bank of the Yangtze River and the barrier due to the influence of the paleo-coastal current from the north, the direction of the Yangtze-derived sediment transport was split on the northeast of the Zhoushan archipelago, and the sediments covered the terrain with trough and ridge. During the high sea level period (7 kyr BP-present), the eastward migration of paleo-coastline had resulted in the increase in accumulation rate. We also conclude that the sharp increase in accumulation rate near the Yangtze River estuary after ~2 kyr BP was not primarily caused by human activities. The position shifts of the estuary caused by the paleo-coastline migration and sea level oscillations since the Holocene is the main cause controlling the Yangtze

  7. Back-arc basin opening and closure along the southern margin of the Sea of Japan

    NASA Astrophysics Data System (ADS)

    Sato, Hiroshi; Claringbould, Johan; Ishiyama, Tatsuya; Kato, Naoko; Abe, Susumu; Kawasaki, Shinji

    2016-04-01

    Following the tsunami disaster produced by 2001 Off-Tohoku earthquake (M9) along the Pacific coast of Japan, the Japanese government started an intense evaluation of tsunami hazards. This evaluation spanned along the full Japanese coast, including the Sea of Japan coast on the western side of the Japan arc. In the Sea of Japan, tsunamis are produced by crustal faults. As the longer interval of faulting activity, the historical records of tsunamis in the Sea of Japan are not enough for the evaluation of tsunami height. Thus, the evaluation is carried out based on structural analyses of the margin of the Sea of Japan. To get better understanding of the present-day structural geometry and develop a source-fault model in this region, intense seismic reflection profiling has been carried out since 2013. We introduce the results of the seismic reflection profiles and discuss the structural evolution of the southern margin of the Sea of Japan. 2D seismic reflection profiles were acquired using 1950 cu. in. air-gun and 2100 m streamer cable. The seismic profiles provide the image image up to 3 seconds TWT. The southern margin of the Sea of Japan was produced by back-arc opening and post-rift deformation, and the structural evolution of this area is divided into several stages: rifting (25 - 14 Ma), post-rift compression (14 - 5 Ma), weak thrusting (5 - 1 Ma), and strike-slip deformation (1 Ma to present). During the rifting stage that is associated with the fan-shaped opening of the Sea of Japan, grabens and half-grabens were formed trending parallel to the extension of SW-Japan arc. These grabens were filled by syn-rift sediments, and the maximum thickness of basin fill is observed along the southern margin of the rifted crust. The opening of the Sea of Japan ceased as a result of the collision of Izu-Bonin-Mariana arc system at the Izu collision zone on the central part of Honshu, Japan. Soon after the this event, the young Shikoku basin within the Philippine Sea plate

  8. The role of grazing in nutrient-rich areas of the open sea

    SciTech Connect

    Frost, B.W. )

    1991-12-01

    No single factor accounts fully for the persistently low phytoplankton stocks in the nutrient-rich areas of the open sea. However, grazing plays the necessary role of consuming phytoplankton produced in excess of losses due to physical processes and sinking. Without grazing, even if specific growth rate of the phytoplankton is less than optimal for the prevailing light and temperature conditions, as might be so under limitation by a trace nutrient such as Fe, the phytoplankton stock would still accumulate with attendant depletion of nutrients. Observations during spring and summer in the open subarctic Pacific argue against limitation of phytoplankton growth to the point where phytoplankton stock could not increase in the absence of grazing. An ecosystem process model of the phytoplankton-grazer interaction suggests that two processes - grazing control of phytoplankton stock and preferential utilization of NH{sub 4} by the phytoplankton - are sufficient to explain the continuously low phytoplankton stock and high concentrations of macronutrients. However, the grazing control may be exerted on a phytoplankton assemblage structured by Fe limitation. In particular, the intrinsic growth rates of potentially fast-growing diatoms seem to be depressed in the open subarctic Pacific. These conditions probably apply to two other nutrient-rich areas of the open sea, the Pacific equatorial upwelling region and the subantarctic circumpolar ocean, although in the latter region light limitation of phytoplankton growth may be more severe and silica limitation may influence the specific composition of the phytoplankton assemblage.

  9. Two modes of Weddell Sea Bottom Water Production: continental margin gravity currents and open ocean convection, which wins and when?

    NASA Astrophysics Data System (ADS)

    Gordon, Arnold L.

    2014-05-01

    There are 2 processes by which Southern Ocean surface waters may reach into the deep ocean: gravity currents over the continental slope and convection within the open ocean. In February 1977 the Islas Orcadas found clear evidence of the latter process, when it observed the remnants of a convective 'chimney' near Maud Rise, in the Weddell Sea. This observation was key in linking deep ocean convective processes to the "Great Weddell Polynya", a 250,000-km2 area virtually free of sea ice during the winters of 1974-1976. Further research from AWI research vessel Polarstern revealed the vulnerability of central Weddell gyre, particularly in the Maud Rise region, to breakdown of water column stability. Climate forcing related to prolonged period of negative or neutral Southern Annular Mode, as was the situation before the "Great Weddell Polynya", acts to reduce freshwater input to the Weddell Sea and thus serves as a trigger for open ocean convection and Polynya development. Similar condition may be occurred during the1912 Deutschland expedition into the Weddell Sea. We speculate that during glacial times, with sea level 130 m lower and the glacial ice extended to shelf break, with the Southern Annular Mode very much in a prolonged negative mode, open ocean production of Weddell Sea Bottom Water [and perhaps that of the Ross Sea too] was prevalent. The bottom water product during the open ocean convection mode may be expected to be saltier than that produced along the continental margin, which would incorporate glacial melt.

  10. Spatial distributions of polyunsaturated aldehydes and their biogeochemical implications in the Pearl River Estuary and the adjacent northern South China Sea

    NASA Astrophysics Data System (ADS)

    Wu, Zhengchao; Li, Qian P.

    2016-09-01

    This study reports the first comprehensive exploration of the spatial patterns of dissolved and particulate polyunsaturated aldehydes (PUAs), their physical and biological controlling factors, and their potential biogeochemical influences in the Pearl River Estuary (PRE) of the northern South China Sea (NSCS). High levels of total particulate PUAs (0-41 nM) and dissolved PUAs (0.10-0.37 nM) were observed with substantial spatial variation during an intense summer phytoplankton bloom outside the PRE mouth. We found the particulate PUAs strongly correlated with temperature within the high chlorophyll bloom, while showing a generally positive correlation with chlorophyll-a for the entire region. Additionally, the Si/N ratio significantly correlated with the particulate PUAs along the estuary suggesting the important role of silica on PUA production in this region. The dissolved PUAs counterparts exhibited a positive correlation with chlorophyll-a within the high chlorophyll bloom, but a negatively one with temperature outside, reflecting the essential bio-physical coupling effects on the dissolved PUAs distributions in the ocean. Biogeochemical implications of PUAs on the coastal ecosystem include not only the deleterious restriction of high PUAs-producing diatom bloom on copepod population, but also the profound influence of particulate PUAs on the microbial cycling of organic carbon in the NSCS.

  11. The Changing Arctic and Subarctic Environment (CASE): a european network on marine biotic indicators of recent climate changes in the Nordic seas and adjacent domains

    NASA Astrophysics Data System (ADS)

    Deme, I.; Giraudeau, J.; Belt, S. T.; Hald, M.; Husum, K.; Knies, J.; Renssen, H.; Spielhagen, R. F.

    2011-12-01

    The European Marie Curie Initial Training Network CASE (FP7 - ITN) is formalizing long-standing research collaborations in the field of empirical and simulated climate and oceanographic changes in the Nordic and Barents Seas. CASE offers an ideal setting for running integrated and innovative projects on recent (Holocene) Arctic and Subarctic climate changes and implementing a multidisciplinary and intersectorial training on biotic proxies of past marine environments through a Marie Curie Network. The EU-funded 12 CASE PhDs projects are concerned with the sensitivity of marine primary and secondary producers to changes in marine physical aspects, and the invaluable information on past oceanic and climatic conditions given by their fossil remains contained in sedimentary archives. Climate modelling provides complementary physical information. The investigations cover an extended field of disciplines, from micropaleontology, to organic and inorganic geochemistry, and an array of expertise such as taxonomy, molecular and stable isotope geochemistry, and climate modelling. This presentation will provide information on the structure of the consortium, the content and philosophy of the training actions, as well as the main scientific objectives of the various research projects carried out by the CASE partner institutions.

  12. Geophysical interpretation of mantle magmatism in the Seiland province and adjacent Barents Sea: Implications for tectonic emplacement of the Kalak Nappe Complex

    NASA Astrophysics Data System (ADS)

    Pastore, Z.; McEnroe, S. A.; Fichler, C.

    2015-12-01

    The Seiland Igneous Province (SIP) has an exposed area of more than 5500 km2 and is the largest complex of mafic and ultramafic intrusions in northern Fennoscandia. The SIP had a massive plumbing system with deep-seated magmatic conduits that generated more than 25000 km3of igneous melts from the mantle through the continental lithosphere to the surface, at ca 560-570 Ma. The SIP is located within the Kalak Nappe Complex, a part of the Middle Allochthon of the North Norwegian Caledonides. The tectonic development, and movement from its original emplacement onto the Baltica craton is a matter of current debate. The SIP exhibits one of the most pronounced positive Bouguer gravity anomalies in northern Fennoscandia (approximately 100 mGal above background) and a clear magnetic signature. We have identified more than 10 distinct magnetic anomalies related to the Seiland Igneous Province. Here, a 3D gravity and magnetic model of the SIP integrating petrophysical data with gravity and aeromagnetic data is presented. The selected densities for the intrusive range from 2800 to 3400 kg m3, with an average density contrast to the host complex of approximately 400 kg m3. Magnetic susceptibility values, ranging from 0.004 SI to 0.2 SI, show a good correlation with the mapped ultramafic intrusions with few exceptions on the Øksfjord peninsula. A multi-profile based 3D model (IGMAS+) shows the deeper structure of the SIP. Our model suggests an irregular shape with its lower boundary varying in depth from North to South from less than 3 km to 10 Km. Two deep roots have been identified located below Seiland and Sørøya islands, the first root slightly dipping southward with two branches in the upper part. The second root is approximately vertical and T- shaped. This model contributes to the understanding of the tectonic, magmatic and the paleogeographic evolution of the SIP and adds new insights to the study of the rich hydrocarbon basins of the Southern Barents Sea.

  13. Validation of Open-Sea CRYOSAT-2 Data in SAR Mode in the German Bight

    NASA Astrophysics Data System (ADS)

    Dinardo, Salvatore; Benveniste, Jérôme; Fenoglio-Marc, Luciana; Scharroo, Remko

    This work aims to generate and validate the altimetric geophysical parameters measured by the CryoSat-2 in SAR Mode in the temporal interval 2011-2012 in the area of the German Bight at distance to coast larger than 10 Kilometers (open-sea). Instantaneous sea surface height (SSH), significant wave height (SWH) and wind speed at 10 meter from sea surface (U10), measured by CryoSat-2, are compared to in-situ measurements at platforms, buoys and tide gauges and to results from an operational circulation model run by the German Federal Maritime and Hydrographic Agency (BSH). The in-situ data were made available by the Wasser- und Schifffahrtsverwaltung des Bundes (WSV). These stations are part of a network of tide gauges and offshore platforms equipped with continuously operation Global Navigation Satellite System (GNSS) receivers. Since the coordinates of the zero point of the tide gauge are computed in the International Terrestrial Reference Frame (ITRF) the absolute comparison between sea level from tide gauge and altimetry is possible. The relevant in-situ data are sea level, wave and wind data. The CryoSat-2 Data have been Delay-Doppler processed as from the FBR (Full Bit Rate) Level 1A to Level 1B and subsequently re-tracked using the SAMOSA's SAR Echo Model (full solution) and a curve-fitting scheme based on Levenberg-Marquard Least Square Minimization Algorithm. Sea surface height, significant wave height and wind speed at 20 Hz and 1 Hz have been derived. The Delay-Doppler processing (L1B) and the re-tracking processing (L2) has been carried out by the EOP-SER Altimetry Team at ESA/ESRIN. Pseudo pulse-limited (PLRM) data derived from CryoSat-2 in SAR mode and provided via the RADS database are compared with the same parameters derived from the CryoSat-2 SAR Data to estimate possible biases and trends between SAR mode and LRM mode and tune-up the SAR re-tracking scheme. Special attention will be paid to spot trends between SAR and PLRM with respect the orbital

  14. Adjacent segment disease.

    PubMed

    Virk, Sohrab S; Niedermeier, Steven; Yu, Elizabeth; Khan, Safdar N

    2014-08-01

    EDUCATIONAL OBJECTIVES As a result of reading this article, physicians should be able to: 1. Understand the forces that predispose adjacent cervical segments to degeneration. 2. Understand the challenges of radiographic evaluation in the diagnosis of cervical and lumbar adjacent segment disease. 3. Describe the changes in biomechanical forces applied to adjacent segments of lumbar vertebrae with fusion. 4. Know the risk factors for adjacent segment disease in spinal fusion. Adjacent segment disease (ASD) is a broad term encompassing many complications of spinal fusion, including listhesis, instability, herniated nucleus pulposus, stenosis, hypertrophic facet arthritis, scoliosis, and vertebral compression fracture. The area of the cervical spine where most fusions occur (C3-C7) is adjacent to a highly mobile upper cervical region, and this contributes to the biomechanical stress put on the adjacent cervical segments postfusion. Studies have shown that after fusion surgery, there is increased load on adjacent segments. Definitive treatment of ASD is a topic of continuing research, but in general, treatment choices are dictated by patient age and degree of debilitation. Investigators have also studied the risk factors associated with spinal fusion that may predispose certain patients to ASD postfusion, and these data are invaluable for properly counseling patients considering spinal fusion surgery. Biomechanical studies have confirmed the added stress on adjacent segments in the cervical and lumbar spine. The diagnosis of cervical ASD is complicated given the imprecise correlation of radiographic and clinical findings. Although radiological and clinical diagnoses do not always correlate, radiographs and clinical examination dictate how a patient with prolonged pain is treated. Options for both cervical and lumbar spine ASD include fusion and/or decompression. Current studies are encouraging regarding the adoption of arthroplasty in spinal surgery, but more long

  15. TIDE TOOL: Open-Source Sea-Level Monitoring Software for Tsunami Warning Systems

    NASA Astrophysics Data System (ADS)

    Weinstein, S. A.; Kong, L. S.; Becker, N. C.; Wang, D.

    2012-12-01

    A tsunami warning center (TWC) typically decides to issue a tsunami warning bulletin when initial estimates of earthquake source parameters suggest it may be capable of generating a tsunami. A TWC, however, relies on sea-level data to provide prima facie evidence for the existence or non-existence of destructive tsunami waves and to constrain tsunami wave height forecast models. In the aftermath of the 2004 Sumatra disaster, the International Tsunami Information Center asked the Pacific Tsunami Warning Center (PTWC) to develop a platform-independent, easy-to-use software package to give nascent TWCs the ability to process WMO Global Telecommunications System (GTS) sea-level messages and to analyze the resulting sea-level curves (marigrams). In response PTWC developed TIDE TOOL that has since steadily grown in sophistication to become PTWC's operational sea-level processing system. TIDE TOOL has two main parts: a decoder that reads GTS sea-level message logs, and a graphical user interface (GUI) written in the open-source platform-independent graphical toolkit scripting language Tcl/Tk. This GUI consists of dynamic map-based clients that allow the user to select and analyze a single station or groups of stations by displaying their marigams in strip-chart or screen-tiled forms. TIDE TOOL also includes detail maps of each station to show each station's geographical context and reverse tsunami travel time contours to each station. TIDE TOOL can also be coupled to the GEOWARE™ TTT program to plot tsunami travel times and to indicate the expected tsunami arrival time on the marigrams. Because sea-level messages are structured in a rich variety of formats TIDE TOOL includes a metadata file, COMP_META, that contains all of the information needed by TIDE TOOL to decode sea-level data as well as basic information such as the geographical coordinates of each station. TIDE TOOL can therefore continuously decode theses sea-level messages in real-time and display the time

  16. [The role of antarctica in formation of the cenozoic climate and contemporary open sea abyssal fauna].

    PubMed

    Kuznetsov, A P

    2001-01-01

    The key role of the Antarctic continent in the formation of the contemporary (Cenozoic) zonal-contrast climate and related geologically "young" (Postmesozoic) contemporary abyssal fauna of the World Ocean is discussed on the basis of the current concepts of pleitectonics, history of planetary climates, paleobiooceanology, and bioevolution. It has been shown that the flows of cold aerated near-Antarctic waters that started to descend in the open sea abyssal in the middle of Cenozoic were capable of substituting for previously (in Mesozoic) heated (up to 15-20 degrees C) abyssal waters within only 1500-2000 years. Following the descending near-Antarctic waters, the shallow and cold water oxyphilic fauna assimilated the abyssal zone that had been warm water and weakly populated. PMID:15926327

  17. Daily Variation Analysis of Atmospheric Turbulence from Inland to Open Sea

    NASA Astrophysics Data System (ADS)

    Shao, S. Y.; Li, X. B.; Li, Y. J.; Zhu, W. Y.; Kang, D. Y.; Fan, C. Y.; Weng, N. Q.

    2016-02-01

    Random fluctuation of turbulence brings random fluctuation of refractive index, which makes atmosphere become a random fluctuation medium and destroys the coherence of light wave especially laser transferring in it. Exploration of atmospheric turbulence is essentially investigation of atmospheric refractive index. The atmospheric structure constant of refractive index is a basic parameter of expressing atmospheric turbulence, and was measured using HTP-2 micro-thermal meter at different areas from inland to open sea. It is analysed that the relation of atmospheric structure constant of refractive index with corresponding temperature and wind speed. The conclusion of turbulence and main influencing factors is to deepen the research in atmospheric optical transmission, and to provide data support for the siting of ship board photoelectric systems.

  18. The Role of Geomagnetic Cues in Green Turtle Open Sea Navigation

    PubMed Central

    Benhamou, Simon; Sudre, Joël; Bourjea, Jérome; Ciccione, Stéphane; De Santis, Angelo; Luschi, Paolo

    2011-01-01

    Background Laboratory and field experiments have provided evidence that sea turtles use geomagnetic cues to navigate in the open sea. For instance, green turtles (Chelonia mydas) displaced 100 km away from their nesting site were impaired in returning home when carrying a strong magnet glued on the head. However, the actual role of geomagnetic cues remains unclear, since magnetically treated green turtles can perform large scale (>2000 km) post-nesting migrations no differently from controls. Methodology/Principal Findings In the present homing experiment, 24 green turtles were displaced 200 km away from their nesting site on an oceanic island, and tracked, for the first time in this type of experiment, with Global Positioning System (GPS), which is able to provide much more frequent and accurate locations than previously used tracking methods. Eight turtles were magnetically treated for 24–48 h on the nesting beach prior to displacement, and another eight turtles had a magnet glued on the head at the release site. The last eight turtles were used as controls. Detailed analyses of water masses-related (i.e., current-corrected) homing paths showed that magnetically treated turtles were able to navigate toward their nesting site as efficiently as controls, but those carrying magnets were significantly impaired once they arrived within 50 km of home. Conclusions/Significance While green turtles do not seem to need geomagnetic cues to navigate far from the goal, these cues become necessary when turtles get closer to home. As the very last part of the homing trip (within a few kilometers of home) likely depends on non-magnetic cues, our results suggest that magnetic cues play a key role in sea turtle navigation at an intermediate scale by bridging the gap between large and small scale navigational processes, which both appear to depend on non-magnetic cues. PMID:22046329

  19. Oceanic distributions and air-sea fluxes of biogenic halocarbons in the open ocean

    NASA Astrophysics Data System (ADS)

    Chuck, Adele L.; Turner, Suzanne M.; Liss, Peter S.

    2005-10-01

    Surface seawater and atmospheric concentrations of methyl iodide, chloroiodomethane, bromoform, dichlorobromomethane, and chlorodibromethane were measured during three open ocean cruises in the Atlantic and Southern oceans. The measurements spanned a longitudinal range of 115°, between 50°N and 65°S. The saturation anomalies and the instantaneous air-sea fluxes of the gases during one of these cruises (ANT XVIII/1) are presented and discussed. Methyl iodide and chloroiodomethane were highly supersaturated (>1000%) throughout the temperate and tropical regions, with calculated mean fluxes of 15 and 5.5 nmol m-2 d-1, respectively. The oceanic emissions of the brominated compounds were less substantial, and a significant area of the temperate Atlantic Ocean was found to be a sink for bromoform. Correlation analyses have been used to investigate possible controls on the concentrations of these gases. In particular, the relationship of CH3I with sea surface temperature and light is discussed, with the tentative conclusion that this compound may be formed abiotically.

  20. Visible and thermal imaging of sea ice and open water from Coast Guard Arctic Domain Awareness flights

    NASA Astrophysics Data System (ADS)

    Chickadel, C. C.; Lindsay, R. W.; Clark, D.

    2014-12-01

    An uncooled thermal camera (microbolometer) and RGB camera were mounted in the tail section of a US Coast Guard HC-130 to observe sea ice, open water, and cloud tops through the open rear cargo doors during routine Arctic Domain Awareness (ADA) flights. Recent flights were conducted over the Beaufort Sea in June, July, and August of 2014, with flights planned for September and October. Thermal and visible images were collected at low altitude (100m) during times when the cargo doors were open and recorded high resolution information on ice floes, melt ponds, and surface temperature variability associated with the marginal ice zone (MIZ). These observations of sea ice conditions and surface water temperatures will be used to characterize floe size development and the temperature and albedo of ice ponds and leads. This information will allow for a detailed characterization of sea ice that can be used in process studies and for model evaluation, calibration of satellite remote sensing products, and initialization of sea ice prediction schemes.

  1. A model of oceanic development by ridge jumping: Opening of the Scotia Sea

    NASA Astrophysics Data System (ADS)

    Maldonado, Andrés; Bohoyo, Fernando; Galindo-Zaldívar, Jesús; Hernández-Molina, Fº. Javier; Lobo, Francisco J.; Lodolo, Emanuele; Martos, Yasmina M.; Pérez, Lara F.; Schreider, Anatoly A.; Somoza, Luis

    2014-12-01

    Ona Basin is a small intra-oceanic basin located in the southwestern corner of the Scotia Sea. This region is crucial for an understanding of the early phases of opening of Drake Passage, since it may contain the oldest oceanic crust of the entire western Scotia Sea, where conflicting age differences from Eocene to Oligocene have been proposed to date. The precise timing of the gateway opening between the Pacific and Atlantic oceans, moreover, has significant paleoceanographic and global implications. Two sub-basins are identified in this region, the eastern and western Ona basins, separated by the submarine relief of the Ona High. A dense geophysical data set collected during the last two decades is analyzed here. The data include multichannel seismic reflection profiles, and magnetic and gravimetric data. The oceanic basement is highly deformed by normal, reverse and transcurrent faults, as well as affected by deep intrusions from the mantle. The initial extension and continental thinning, with subsequent oceanic spreading, were followed by compression and thrusting. Several elongated troughs, bounded by faults, depict a thick sequence of depositional units in the basin. Eight seismic units are identified in a deep trough of the eastern Ona Basin. The deposits reach a thickness of 5 km, a consistent value not previously reported from the Scotia Sea. A body of chaotic seismic facies is also observed above the thinned continental crust of the Ona High. Magnetic seafloor anomalies older than C10 (~ 28.5 Ma) may be present in the region. The anomalies could include up to chron C12r (~ 32 Ma), although their identification is difficult, since the amplitude is subdued and the original oceanic crust was highly deformed by later faulting and thrusting. The magnetic anomaly distribution is not congruent with seafloor spreading from a single ridge. The basin plain is tilted and subducted southwestward below the South Shetland Islands Block, particularly in the western part

  2. Long-distance swimming by polar bears (Ursus maritimus) of the southern Beaufort Sea during years of extensive open water

    USGS Publications Warehouse

    2014-01-01

    Polar bears (Ursus maritimus Phipps, 1774) depend on sea ice for catching marine mammal prey. Recent sea-ice declines have been linked to reductions in body condition, survival, and population size. Reduced foraging opportunity is hypothesized to be the primary cause of sea-ice-linked declines, but the costs of travel through a deteriorated sea-ice environment also may be a factor. We used movement data from 52 adult female polar bears wearing Global Positioning System (GPS) collars, including some with dependent young, to document long-distance swimming (>50 km) by polar bears in the southern Beaufort and Chukchi seas. During 6 years (2004-2009), we identified 50 long-distance swims by 20 bears. Swim duration and distance ranged from 0.7 to 9.7 days (mean = 3.4 days) and 53.7 to 687.1 km (mean = 154.2 km), respectively. Frequency of swimming appeared to increase over the course of the study. We show that adult female polar bears and their cubs are capable of swimming long distances during periods when extensive areas of open water are present. However, long-distance swimming appears to have higher energetic demands than moving over sea ice. Our observations suggest long-distance swimming is a behavioral response to declining summer sea-ice conditions.

  3. New insight on the opening of the South China Sea basin

    NASA Astrophysics Data System (ADS)

    Hsu, Shu-Kun; Armada, Leo; Doo, Wen-Bin; Yeh, Yi-Ching

    2016-04-01

    The tectonic evolution of the South China Sea (SCS) plays an important role on the geodynamics of Southeast Asia. Recent results from the International Ocean Discovery Program (IODP) Expedition 349 confirmed that the SCS seafloor spreading stopped in the middle Miocene. However, the definite mechanism for the SCS opening is still enigmatic. Using multi-beam bathymetric data, seismic reflection profiles and geomagnetic modeling, we have analyzed the seafloor-spreading pattern and geomagnetic stripes of the SCS. Our results show that an excessive magma supply affecting the SCS occurred at the Early Miocene Climatic Optimum (EMCO). Consequently, four major tectonic events ensued. Firstly, the East Subbasin of the SCS dramatically changed its seafloor spreading direction from north-south to northwest-southeast. Secondly, a northeastward propagating rift occurred in the East Subbasin but stopped in the middle Miocene, just before the cessation of the SCS seafloor spreading. Thirdly, the opening of the SCS extended southwestward and created the Southwest Subbasin. Fourthly, the initiation of the southeastward subduction of the SCS lithosphere occurred and the Manila Trench was formed.

  4. The signatures of stable isotopes δ 15N and δ 13C in anadromous and non-anadromous Coilia nasus living in the Yangtze River, and the adjacent sea waters

    NASA Astrophysics Data System (ADS)

    Wang, Lei; Tang, Wenqiao; Dong, Wenxia

    2015-12-01

    Stable isotopes are increasingly used to investigate seasonal migrations of aquatic organisms. This study employed stable isotopes ( δ 13C and δ 15N) for Coilia nasus from the lower Yangtze River and the adjacent East China Sea to distinguish different ecotypic groups, ascertain trophic nutrition positions, and reflect environmental influences on C. nasus. δ 13C signatures of C. nasus sampled from Zhoushan (ZS), Chongming (CM), and Jingjiang (JJ) waters were significantly higher than those from the Poyang Lake (PYL) ( P < 0.05). By contrast, δ 15N signatures of C. nasus in ZS, CM, and JJ groups were significantly lower than those in PYL group ( P < 0.05). Basing on δ 13C and δ 15N signatures, we could distinguish anadromous (ZS, CM, and JJ) and non-anadromous (PYL) groups. The trophic level (TL) of anadromous C. nasus ranged from 2.90 to 3.04, whereas that of non-anadromous C. nasus was 4.38. C. nasus occupied the middle and top nutrition positions in the marine and Poyang Lake food webs, respectively. C. nasus in Poyang Lake were significantly more enriched in δ 15N but depleted in δ 13C, suggesting that anthropogenic nutrient inputs and terrigenous organic carbon are important to the Poyang Lake food web. This study is the first to apply δ 15N and δ 13C to population assignment studies of C. nasus in the Yangtze River and its affiliated waters. Analysis of stable isotopes ( δ 15N and δ 13C) is shown to be a useful tool for discriminating anadromous and non-anadromous C. nasus.

  5. Estimation of the Aral Sea state predictability based on the open data sources and the unique field observations

    NASA Astrophysics Data System (ADS)

    Izhitskiy, Alexander; Ayzel, Georgy; Zavialov, Peter; Kurbaniyazov, Abilgazi

    2016-04-01

    The Aral Sea, formerly one of the four largest lakes in the world, has lost over 90% of its volume during the dramatical dessication mainly caused by the severe alteration of water budget of the basin. Shrinkage of the Aral Sea resulted in profound changes of the lake's ecosystem, that became a subject for a number of publications based on a wide range of methods such as field observations, remote sensing data analysis and numerical modeling. However, by the early 21th century, the number of field studies decreased significantly due to almost complete cessation of navigation and displacement of the Aral's shoreline far away from roads and other infrastructure. Thus, only a small amount of field data (salinity, temperature, etc.) for different regions of the lake is available for the last two decades. On the other hand, a set of the open data sources (sea level variability, atmospheric reanalysis) were developed for the region. The main idea of the presented study is to estimate the possibility of prediction of the Aral Sea state using coupled system of basic geoanalysis tools, numerical modeling of hydrological cycle (both for sea and land-surface interactions with atmosphere) and state-of-art machine learning techniques. Firstly, available in situ data, obtained in the Aral Sea by Shirshov Institute and other researchers, are concerned as the "base points of state" for each year within the studied period. Secondly, consistent patterns in the interannual variability of all other available parameters, taken from the open data sources and numerical modeling predictions, are founded out. As a result, such an approach allows predicting the future state of sea basing on the possible climatic scenario.

  6. Phytoplankton responses to atmospheric metal deposition in the coastal and open-ocean Sargasso Sea.

    PubMed

    Mackey, Katherine R M; Buck, Kristen N; Casey, John R; Cid, Abigail; Lomas, Michael W; Sohrin, Yoshiki; Paytan, Adina

    2012-01-01

    This study investigated the impact of atmospheric metal deposition on natural phytoplankton communities at open-ocean and coastal sites in the Sargasso Sea during the spring bloom. Locally collected aerosols with different metal contents were added to natural phytoplankton assemblages from each site, and changes in nitrate, dissolved metal concentration, and phytoplankton abundance and carbon content were monitored. Addition of aerosol doubled the concentrations of cadmium (Cd), cobalt (Co), copper (Cu), iron (Fe), manganese (Mn), and nickel (Ni) in the incubation water. Over the 3-day experiments, greater drawdown of dissolved metals occurred in the open ocean water, whereas little metal drawdown occurred in the coastal water. Two populations of picoeukaryotic algae and Synechococcus grew in response to aerosol additions in both experiments. Particulate organic carbon increased and was most sensitive to changes in picoeukaryote abundance. Phytoplankton community composition differed depending on the chemistry of the aerosol added. Enrichment with aerosol that had higher metal content led to a 10-fold increase in Synechococcus abundance in the oceanic experiment but not in the coastal experiment. Enrichment of aerosol-derived Co, Mn, and Ni were particularly enhanced in the oceanic experiment, suggesting the Synechococcus population may have been fertilized by these aerosol metals. Cu-binding ligand concentrations were in excess of dissolved Cu in both experiments, and increased with aerosol additions. Bioavailable free hydrated Cu(2+) concentrations were below toxicity thresholds throughout both experiments. These experiments show (1) atmospheric deposition contributes biologically important metals to seawater, (2) these metals are consumed over time scales commensurate with cell growth, and (3) growth responses can differ between distinct Synechococcus or eukaryotic algal populations despite their relatively close geographic proximity and taxonomic similarity

  7. Phytoplankton responses to atmospheric metal deposition in the coastal and open-ocean Sargasso Sea

    PubMed Central

    Mackey, Katherine R. M.; Buck, Kristen N.; Casey, John R.; Cid, Abigail; Lomas, Michael W.; Sohrin, Yoshiki; Paytan, Adina

    2012-01-01

    This study investigated the impact of atmospheric metal deposition on natural phytoplankton communities at open-ocean and coastal sites in the Sargasso Sea during the spring bloom. Locally collected aerosols with different metal contents were added to natural phytoplankton assemblages from each site, and changes in nitrate, dissolved metal concentration, and phytoplankton abundance and carbon content were monitored. Addition of aerosol doubled the concentrations of cadmium (Cd), cobalt (Co), copper (Cu), iron (Fe), manganese (Mn), and nickel (Ni) in the incubation water. Over the 3-day experiments, greater drawdown of dissolved metals occurred in the open ocean water, whereas little metal drawdown occurred in the coastal water. Two populations of picoeukaryotic algae and Synechococcus grew in response to aerosol additions in both experiments. Particulate organic carbon increased and was most sensitive to changes in picoeukaryote abundance. Phytoplankton community composition differed depending on the chemistry of the aerosol added. Enrichment with aerosol that had higher metal content led to a 10-fold increase in Synechococcus abundance in the oceanic experiment but not in the coastal experiment. Enrichment of aerosol-derived Co, Mn, and Ni were particularly enhanced in the oceanic experiment, suggesting the Synechococcus population may have been fertilized by these aerosol metals. Cu-binding ligand concentrations were in excess of dissolved Cu in both experiments, and increased with aerosol additions. Bioavailable free hydrated Cu2+ concentrations were below toxicity thresholds throughout both experiments. These experiments show (1) atmospheric deposition contributes biologically important metals to seawater, (2) these metals are consumed over time scales commensurate with cell growth, and (3) growth responses can differ between distinct Synechococcus or eukaryotic algal populations despite their relatively close geographic proximity and taxonomic similarity. PMID

  8. Open reading frame 3, which is adjacent to the mycocerosic acid synthase gene, is expressed as an acyl coenzyme A synthase in Mycobacterium bovis BCG.

    PubMed Central

    Fitzmaurice, A M; Kolattukudy, P E

    1997-01-01

    The aim of this study was to test for expression of a 900-bp open reading frame (ORF), ORF3, located at the 5' end of the mycocerosic acid synthase gene in Mycobacterium bovis BCG and to determine the nature of the ORF3 protein. ORF3 was expressed as a 61-kDa C-terminal fusion protein with glutathione S-transferase in Escherichia coli. Polyclonal rabbit antiserum, prepared against this fusion protein, cross-reacted with a 65-kDa protein in M. bovis BCG crude extracts. Since this protein was larger than that predicted from the nucleotide sequence (32 kDa), ORF3 was resequenced, revealing an ORF of 1,749 bp that encodes a 64.8-kDa protein containing 583 amino acids. Reverse transcription-PCR revealed that ORF3 is expressed in M. bovis BCG. The ORF3 product has a high degree of similarity to the acyladenylate family of enzymes. Immunoaffinity absorption chromatography was used to isolate the 65-kDa cross-reacting protein from M. bovis BCG. This purified protein catalyzed coenzyme A (CoA) ester synthesis of n-C10 to n-C18 fatty acids but not mycocerosic acids. ORF3 antibodies severely inhibited acyl-CoA synthase activities of the purified protein and extracts of M. bovis BCG, Mycobacterium smegmatis, and E. coli. They also showed immunological cross-reactivity with proteins in these extracts. Both the ORF3 protein and the acyl-CoA synthase activity were located in the cell cytosol or were loosely associated with the cell membrane. These results indicate that ORF3 encodes an acyl-CoA synthase-like protein. PMID:9098059

  9. Bioremediation efficiency of the largest scale artificial Porphyra yezoensis cultivation in the open sea in China.

    PubMed

    Wu, Hailong; Huo, Yuanzi; Zhang, Jianheng; Liu, Yuanyuan; Zhao, Yating; He, Peimin

    2015-06-15

    The bioremediation efficiency of China's largest scale Porphyra yezoensis cultivation for removing dissolved nutrients and controlling harmful algae was studied in the radial sandbanks waters of Jiangsu Province in the year 2012-2013. Mean nutrient concentration values in the P. yezoensis cultivation area were significantly lower than those in the non-cultivation area, especially during the cultivation season (p<0.05). Tissue nitrogen and phosphorus contents of seaweeds were 5.99-0.80% (dry weight (DW)) and 0.16-0.19% (DW), respectively. Production of P. yezoensis was 58950.87tons DW. Based on these values, 3688.15tons of tissue nitrogen and 105.61tons of tissue phosphorus were removed by harvesting P. yezoensis. The richness index of the red tide species Skeleton emacostatum declined from 0.32 to 0.05 during the P. yezoensis cultivation season. These results indicate that large-scale cultivation of P. yezoensis can be used to efficiently alleviate eutrophication and control harmful algae blooms in open sea. PMID:25865344

  10. Halimeda bioherms along an open seaway: Miskito Channel, Nicaraguan Rise, SW Caribbean Sea

    NASA Astrophysics Data System (ADS)

    Hine, A. C.; Hallock, Pamela; Harris, M. W.; Mullins, H. T.; Belknap, D. F.; Jaap, W. C.

    1988-03-01

    A recent research cruise to examine small, detached carbonate platforms situated on the Nicaraguan Rise in the SW Caribbean Sea has revealed the presence of numerous Halimeda bioherms. Based upon interpretations from seismic reflection data some exceed 140 m in relief. This is the first documented occurrence of these green-algal buildups in the Caribbean/Bahama Bank region. The Halimeda bioherms form a nearly continuous band that borders the margins of the Miskito Channel—a shallow, open, 125 km long seaway. This 220 m deep channel bisects the Miskito Bank which is a major carbonate shelf. In seismic profile the bioherms appear acoustically “soft” and reveal a local relief of 20 30 m. Tops of these features lie in about 40 50 m of water. Samples from dredge hauls are coarse, poorly cemented packstones/grainstones which are dominated by largely unbroken, disarticulated Halimeda segments set in a poorly sorted sandy matrix. Exposed surfaces were stained brown. Very little living material was brought up in the dredges. The significance of these bioherms and their full extent in the Caribbean are not understood. Undoubtedly, further study will provide important answers concerning their role in the geologic development of Caribbean carbonate platforms.

  11. Idealised simulations of open cellular convection and horizontal wind fluctuations over the North Sea

    NASA Astrophysics Data System (ADS)

    Vincent, Claire Louise; Hahmann, Andrea; Pinson, Pierre; Giebel, Gregor

    2010-05-01

    The Weather Research and Forecasting (WRF) model was used to study the skill, sensitivity and limitations of a mesoscale model in predicting wind speed fluctuations on time scales of tens of minutes to hours. The work was motivated by the severely variable wind conditions that are often observed at the Horns Rev wind farm in the Danish North Sea. From a wind energy perspective, such fluctuations present challenges for both electricity transmission system operators, who must ensure reliability of the electricity grid, and wind farm operators, who must avoid financial losses associated with sudden and unexpected dips in wind power. Good forecasts of the onset of severely variable wind conditions are one way of increasing preparedness for such events. WRF was first used to model an episode of intense wind fluctuations that was observed at an offshore meteorological mast near the Horns Rev wind farm on 23-24th October 2002. WRF was able to reproduce large fluctuations in horizontal wind speed with a similar frequency to that of the observed wind fluctuations. Building on this result, WRF was then set up in an idealised framework as a simple simulation of wind blowing over water. The initialisation of the model was based on the actual conditions during a severely variable wind event over the North Sea. The benefit of running the model in an idealised mode was that individual aspects of model performance could be clearly isolated. During the first few hours of simulation, WRF produced unrealistic fluctuations in wind speed that were dominated by the horizontal grid spacing of the model. After 4 to 5 hours, realistic open cellular convection developed, with large fluctuations in horizontal wind speed similar to those observed in the real case. The structure of the convective cells had a spatial scale of about 30 km, which corresponded closely to cloud patterns seen in a visual satellite picture from the same event. The scale of the cells was largely invariant to changes

  12. Interaction of dense shelf water cascading and open-sea convection in the northwestern Mediterranean during winter 2012

    NASA Astrophysics Data System (ADS)

    Durrieu de Madron, X.; Houpert, L.; Puig, P.; Sanchez-Vidal, A.; Testor, P.; Bosse, A.; Estournel, C.; Somot, S.; Bourrin, F.; Bouin, M. N.; Beauverger, M.; Beguery, L.; Calafat, A.; Canals, M.; Cassou, C.; Coppola, L.; Dausse, D.; D'Ortenzio, F.; Font, J.; Heussner, S.; Kunesch, S.; Lefevre, D.; Le Goff, H.; MartíN, J.; Mortier, L.; Palanques, A.; Raimbault, P.

    2013-04-01

    The winter of 2012 experienced peculiar atmospheric conditions that triggered a massive formation of dense water on the continental shelf and in the deep basin of the Gulf of Lions. Multiplatforms observations enabled a synoptic view of dense water formation and spreading at basin scale. Five months after its formation, the dense water of coastal origin created a distinct bottom layer up to a few hundreds of meters thick over the central part of the NW Mediterranean basin, which was overlaid by a layer of newly formed deep water produced by open-sea convection. These new observations highlight the role of intense episodes of both dense shelf water cascading and open-sea convection to the progressive modification of the NW Mediterranean deep waters.

  13. Decreasing intensity of open-ocean convection in the Greenland and Iceland seas

    NASA Astrophysics Data System (ADS)

    Moore, G. W. K.; Våge, K.; Pickart, R. S.; Renfrew, I. A.

    2015-09-01

    The air-sea transfer of heat and fresh water plays a critical role in the global climate system. This is particularly true for the Greenland and Iceland seas, where these fluxes drive ocean convection that contributes to Denmark Strait overflow water, the densest component of the lower limb of the Atlantic Meridional Overturning Circulation (AMOC; ref. ). Here we show that the wintertime retreat of sea ice in the region, combined with different rates of warming for the atmosphere and sea surface of the Greenland and Iceland seas, has resulted in statistically significant reductions of approximately 20% in the magnitude of the winter air-sea heat fluxes since 1979. We also show that modes of climate variability other than the North Atlantic Oscillation (NAO; refs , , , , ) are required to fully characterize the regional air-sea interaction. Mixed-layer model simulations imply that further decreases in atmospheric forcing will exceed a threshold for the Greenland Sea whereby convection will become depth limited, reducing the ventilation of mid-depth waters in the Nordic seas. In the Iceland Sea, further reductions have the potential to decrease the supply of the densest overflow waters to the AMOC (ref. ).

  14. The opening of the South China Sea revisited with high-density magnetic tracks

    NASA Astrophysics Data System (ADS)

    Song, T.; Li, C.

    2011-12-01

    Magnetic anomalies bear extremely rich information on Mesozoic and Cenozoic tectonic evolution of the South China Sea(SCS). Through integrated analyses of magnetic, gravity and reflection seismic data, we define the continent-ocean boundary(COB) around the South China Sea continental margin, and find that the COB coincides very well with a transition zone from mostly positive to negative free-air gravity anomalies. This accurate outlining of the COB is critical for better tracing magnetic anomalies induced by the oceanic crust. Models with a single episode of seafloor spreading are inconsistent with the abrupt magnetic contrast between the East and Southwest Sub-basins.Previous efforts in dating the oceanic crust here are based primarily on very limited numbers of magnetic surveys. Here we take advantage of high-density digital magnetic tracks compiled from multiple surveys to enhance magnetic anomalies caused by the shallow basaltic layer via 2D band-pass filtering. This operation effectively reduces short-wavelength noises and suppresses long-wavelength background anomalies due mostly to deep magnetic sources in the lower crust and uppermost mantle. It is recognized that the likely oldest magnetic anomaly near the northern continental margin is C12 according to the magnetic time scale CK95. Near the southern continental margin, magnetic anomalies are less recognizable and the anomaly C12 appears to be missing. These differences show an asymmetrical opening style with respect to the relict spreading center, and the northern part appears to have slightly faster spreading rates than to the south. The magnetic anomalies C8(M1 and M2, ~26 Ma)represent important magnetic boundaries within the oceanic basin, and are possibly related to changes in spreading rates and magmatic intensities. The magnetic evidence for a previously proposed ridge jump after the anomaly C7 is not clear. To accurately estimate the depths to the top of the basalt layer used in magnetic modeling

  15. Seasonal Hypoxia on the Shelf and Shoaling of the Permanent Oxycline in the Open Sea: Two Faces of the Black Sea Deoxygenation

    NASA Astrophysics Data System (ADS)

    Capet, Arthur; Stanev, Emil; Beckers, Jean-Marie; Grégoire, Marilaure

    2016-04-01

    The Black Sea is highly sensitive to external forcings and constitutes a natural laboratory to study the interplays of atmospheric warming and eutrophication on deoxygenation dynamics. Two decades of eutrophication were followed by a sudden reduction of nutrient loads in the late 1980s. Warm and cold air temperature cycles (5-10 years) follow atmospheric oscillation patterns, with a clear warming affecting the recent decades. On the Black Sea north western shelf (<120m), which receives more that 3/4 of the river runoff, seasonal hypoxia occurs when summer stratification prevents atmospheric fluxes to compensate for the respiration of organic matter accumulated in the lower water column and the sediments. A former multidecadal 3D model study (1) indicated that current monitoring do not provide a satisfactorily assessment of hypoxia, (2) revealed the inertia due to the benthic accumulation of organic matter during eutrophication period and (3) estimated the nutrient reduction effort required in adaptation to atmospheric warming. In the open basin (120-2000m), the permanent interface between anoxic and oxic waters is subject to vertical migration as the ventilation ensured by dense water formation balances the respiration of sinking organic matter. The analysis of R/V casts and ARGO profiles revealed that the oxycline has shoaled from 140 to 90m between 1955 and present years, while the basin lost 36 % of its oxygen inventory. While the interactions between seasonal hypoxia on the shelf and the shoaling oxic interface in the open basin are not clear, both dynamics will face atmospheric warming and new industrial development of the lower danube watershed. We discuss the specific monitoring and modelling efforts required to assess the environmental and economical threat cast by further deoxygenation in the Black Sea.

  16. Future acidification of marginal seas: A comparative study of the Japan/East Sea and the South China Sea

    NASA Astrophysics Data System (ADS)

    Luo, Yiming; Boudreau, Bernard P.

    2016-06-01

    The response of marginal (peripheral) seas to ocean acidification on short and long time scales is not well established. Through modeling, we examine the future acidification of two adjacent marginal seas, the South China Sea (SCS) and the Japan/East Sea (J/ES). Our results illustrate the importance of unique features in determining their acidification. The J/ES basin will become completely undersaturated with regard to calcite rapidly in the next few decades, while the SCS basin will experience relatively slower acidification. During its acidification, the J/ES will continually act as a sink for atmospheric CO2, whereas the SCS will temporarily switch from a source to a sink during the peak pCO2 interval, only to return slowly to being a source again. Marginal sea acidification will be determined by multiple factors, including their connections with the open ocean and their unique physical and biogeochemical dynamics, in addition to the level of atmospheric CO2.

  17. Impacts of open-ocean deep convection in the Weddell Sea on coastal and bottom water temperature

    NASA Astrophysics Data System (ADS)

    Wang, Zhaomin; Wu, Yang; Lin, Xia; Liu, Chengyan; Xie, Zelin

    2016-07-01

    A high resolution global ocean-sea ice model is employed to investigate the impacts of open-ocean deep convection on coastal and bottom water temperature in the Weddell Sea. The imposed strong and persistent cyclonic wind forcing and the large loss of bottom water weaken the stratification and eventually trigger the occurrence of open-ocean deep convection in the southern limb of the Weddell Gyre in this model. The production rate of the bottom water induced by the deep convection is estimated to be about 5 Sv (1 Sv = 106 m3/s) for a polynya with a similar size to that of the observed Weddell Polynya in the mid-1970s. The cooling induced by deep convection at mid-depth is transported towards the shelf regions by standing meanders or eddies to affect the basal melting of ice shelves, and is transported westward by an intensified slope current; interior coastal temperature in regions with a broader continental shelf is less affected by the deep convection, as the intensified slope current acts to suppress heat exchanges across the shelf break. Also, the deep convection causes warming in the Weddell bottom water around the convection site, when the simulated polynya size is similar to that of the observed Weddell Polynya in the mid-1970s. This finding sheds light on the observed non-monotonic decadal change (cooling between 1984-1992 and warming between 1998-2008) in the Weddell bottom water temperature. When the simulated polynya further develops into a large size across the Weddell Sea, the sustained broad deep convection causes large cooling in the bottom water in the western Weddell Sea and warming in the eastern Weddell Sea, with the bottom water temperature also being strongly modulated by a greatly intensified Weddell Gyre.

  18. 34 CFR 76.791 - On what basis does an SEA determine whether a charter school LEA that opens or significantly...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... charter school LEA that opens or significantly expands its enrollment is eligible to receive funds under a covered program? (a) For purposes of this subpart, an SEA must determine whether a charter school LEA is... the charter school LEA on or after the date the charter school LEA opens or significantly expands...

  19. 34 CFR 76.791 - On what basis does an SEA determine whether a charter school LEA that opens or significantly...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... charter school LEA that opens or significantly expands its enrollment is eligible to receive funds under a covered program? (a) For purposes of this subpart, an SEA must determine whether a charter school LEA is... the charter school LEA on or after the date the charter school LEA opens or significantly expands...

  20. 34 CFR 76.791 - On what basis does an SEA determine whether a charter school LEA that opens or significantly...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... charter school LEA that opens or significantly expands its enrollment is eligible to receive funds under a covered program? (a) For purposes of this subpart, an SEA must determine whether a charter school LEA is... the charter school LEA on or after the date the charter school LEA opens or significantly expands...

  1. 34 CFR 76.791 - On what basis does an SEA determine whether a charter school LEA that opens or significantly...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... charter school LEA that opens or significantly expands its enrollment is eligible to receive funds under a covered program? (a) For purposes of this subpart, an SEA must determine whether a charter school LEA is... the charter school LEA on or after the date the charter school LEA opens or significantly expands...

  2. 34 CFR 76.791 - On what basis does an SEA determine whether a charter school LEA that opens or significantly...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... charter school LEA that opens or significantly expands its enrollment is eligible to receive funds under a covered program? (a) For purposes of this subpart, an SEA must determine whether a charter school LEA is... the charter school LEA on or after the date the charter school LEA opens or significantly expands...

  3. Sea ice melt onset associated with lead opening during the spring/summer transition near the North Pole

    NASA Astrophysics Data System (ADS)

    Vivier, Frédéric; Hutchings, Jennifer K.; Kawaguchi, Yusuke; Kikuchi, Takashi; Morison, James H.; Lourenço, Antonio; Noguchi, Tomohide

    2016-04-01

    In the central Arctic Ocean, autonomous observations of the ocean mixed layer and ice documented the transition from cold spring to early summer in 2011. Ice-motion measurements using GPS drifters captured three events of lead opening and ice ridge formation in May and June. Satellite sea ice concentration observations suggest that locally observed lead openings were part of a larger-scale pattern. We clarify how these ice deformation events are linked with the onset of basal sea ice melt, which preceded surface melt by 20 days. Observed basal melt and ocean warming are consistent with the available input of solar radiation into leads, once the advent of mild atmospheric conditions prevents lead refreezing. We use a one-dimensional numerical simulation incorporating a Local Turbulence Closure scheme to investigate the mechanisms controlling basal melt and upper ocean warming. According to the simulation, a combination of rapid ice motion and increased solar energy input at leads promotes basal ice melt, through enhanced mixing in the upper mixed layer, while slow ice motion during a large lead opening in mid-June produced a thin, low-density surface layer. This enhanced stratification near the surface facilitates storage of solar radiation within the thin layer, instead of exchange with deeper layers, leading to further basal ice melt preceding the upper surface melt.

  4. 137Cs, 239+240Pu and 240Pu/239Pu atom ratios in the surface waters of the western North Pacific Ocean, eastern Indian Ocean and their adjacent seas.

    PubMed

    Yamada, Masatoshi; Zheng, Jian; Wang, Zhong-Liang

    2006-07-31

    Surface seawater samples were collected along the track of the R/V Hakuho-Maru cruise (KH-96-5) from Tokyo to the Southern Ocean. The (137)Cs activities were determined for the surface waters in the western North Pacific Ocean, the Sulu and Indonesian Seas, the eastern Indian Ocean, the Bay of Bengal, the Andaman Sea, and the South China Sea. The (137)Cs activities showed a wide variation with values ranging from 1.1 Bq m(-3) in the Antarctic Circumpolar Region of the Southern Ocean to 3 Bq m(-3) in the western North Pacific Ocean and the South China Sea. The latitudinal distributions of (137)Cs activity were not reflective of that of the integrated deposition density of atmospheric global fallout. The removal rates of (137)Cs from the surface waters were roughly estimated from the two data sets of Miyake et al. [Miyake Y, Saruhashi K, Sugimura Y, Kanazawa T, Hirose K. Contents of (137)Cs, plutonium and americium isotopes in the Southern Ocean waters. Pap Meteorol Geophys 1988;39:95-113] and this study to be 0.016 yr(-1) in the Sulu and Indonesian Seas, 0.033 yr(-1) in the Bay of Bengal and Andaman Sea, and 0.029 yr(-1) in the South China Sea. These values were much lower than that in the coastal surface water of the western Northwest Pacific Ocean. This was likely due to less horizontal and vertical mixing of water masses and less scavenging. (239+240)Pu activities and (240)Pu/(239)Pu atom ratios were also determined for the surface waters in the western North Pacific Ocean, the Sulu and Indonesian Seas and the South China Sea. The (240)Pu/(239)Pu atom ratios ranged from 0.199+/-0.026 to 0.248+/-0.027 on average, and were significantly higher than the global stratospheric fallout ratio of 0.18. The contributions of the North Pacific Proving Grounds close-in fallout Pu were estimated to be 20% for the western North Pacific Ocean, 39% for the Sulu and Indonesian Seas and 42% for the South China Sea by using the two end-member mixing model. The higher (240)Pu/(239)Pu

  5. 1. A BRICK AND CONCRETE FAN HOUSING ADJACENT TO ONE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. A BRICK AND CONCRETE FAN HOUSING ADJACENT TO ONE OF THE ADIT OPENINGS (VIEW TO THE NORTH). - Foster Gulch Mine, Fan Housing, Bear Creek 1 mile Southwest of Town of Bear Creek, Red Lodge, Carbon County, MT

  6. Observed microphysical changes in Arctic mixed-phase clouds when transitioning from sea-ice to open ocean

    NASA Astrophysics Data System (ADS)

    Young, Gillian; Jones, Hazel M.; Crosier, Jonathan; Bower, Keith N.; Darbyshire, Eoghan; Taylor, Jonathan W.; Liu, Dantong; Allan, James D.; Williams, Paul I.; Gallagher, Martin W.; Choularton, Thomas W.

    2016-04-01

    The Arctic sea-ice is intricately coupled to the atmosphere[1]. The decreasing sea-ice extent with the changing climate raises questions about how Arctic cloud structure will respond. Any effort to answer these questions is hindered by the scarcity of atmospheric observations in this region. Comprehensive cloud and aerosol measurements could allow for an improved understanding of the relationship between surface conditions and cloud structure; knowledge which could be key in validating weather model forecasts. Previous studies[2] have shown via remote sensing that cloudiness increases over the marginal ice zone (MIZ) and ocean with comparison to the sea-ice; however, to our knowledge, detailed in-situ data of this transition have not been previously presented. In 2013, the Aerosol-Cloud Coupling and Climate Interactions in the Arctic (ACCACIA) campaign was carried out in the vicinity of Svalbard, Norway to collect in-situ observations of the Arctic atmosphere and investigate this issue. Fitted with a suite of remote sensing, cloud and aerosol instrumentation, the FAAM BAe-146 aircraft was used during the spring segment of the campaign (Mar-Apr 2013). One case study (23rd Mar 2013) produced excellent coverage of the atmospheric changes when transitioning from sea-ice, through the MIZ, to the open ocean. Clear microphysical changes were observed, with the cloud liquid-water content increasing by almost four times over the transition. Cloud base, depth and droplet number also increased, whilst ice number concentrations decreased slightly. The surface warmed by ~13 K from sea-ice to ocean, with minor differences in aerosol particle number (of sizes corresponding to Cloud Condensation Nuclei or Ice Nucleating Particles) observed, suggesting that the primary driver of these microphysical changes was the increased heat fluxes and induced turbulence from the warm ocean surface as expected. References: [1] Kapsch, M.L., Graversen, R.G. and Tjernström, M. Springtime

  7. The opening of the South China Sea: Driven by Pacific subduction, or by India-Eurasia collision?

    NASA Astrophysics Data System (ADS)

    Li, Z.

    2012-12-01

    The opening of the South China Sea (SCS) between ca. 30 Ma and ca. 16 Ma is widely believed to have been caused by the extrusion of the Indochina Block, and is therefore a consequence of India's indentation into the Eurasian continent (e.g., Briais et al., 1993). The main evidence used for such a connection is the roughly consistent ages between the activation of the Red River Fault and the beginning of the SCS opening. However, such a model would predict a maximum opening of the SCS proximal to the Red River Fault, an eastward propagation of the SCS, and compressional deformation in front (south) of the extruding Indochina Block. None of these predictions has been borne out by geophysical and geological data around the SCS. The model also could not explain the continental rifting along the margins of the SCS that started from ca. 60 Ma. An alternative model is that the opening of the SCS was caused by slab-pull of a paleo-SCS (Holloway, 1982; Taylor and Hayes, 1983). Here I argue that the latter model is more consistent with the kinematics around the opening of the SCS, as well as the overall evolution of the Western Pacific margin. The East Asian segment of the Pacific Margin was an Andean-type active margin between ca. 280 Ma and 90 Ma, involving flat-subduction of an oceanic plateau and slab foundering/roll-back. This Andean-type active margin appears to have terminated at around 90 Ma, and the subduction zone jumped ocean-ward, leaving a proto-SCS basin along the continental margin. The ocean-ward subduction of this old oceanic crust started sometime in the early Cenozoic, and the slab-pull effect caused the rifting of the continental margin from ca. 60 Ma, which eventually led to the opening of the South China Sea from ca. 30 Ma. The continental rifting leading to the opening of the SCS was part of the transition of an Andean-type plate margin to the Western Pacific-type from around 90 Ma along the entire Western Pacific, due to the overall ocean-ward retreat

  8. Carbon flux to the deep in three open sites of the Southern European Seas (SES)

    NASA Astrophysics Data System (ADS)

    Gogou, Alexandra; Sanchez-Vidal, Anna; Durrieu de Madron, Xavier; Stavrakakis, Spyros; Calafat, Antoni M.; Stabholz, Marion; Psarra, Stella; Canals, Miquel; Heussner, Serge; Stavrakaki, Ioanna; Papathanassiou, Evangelos

    2014-01-01

    In this study, we investigate the strength and efficiency of carbon sequestration in the Southern European Seas (SES), by analyzing the export of POC at three deep sites located in the Western Mediterranean Sea (WMED), the Eastern Mediterranean Sea (EMED) and the Black Sea (BS). We combine estimations of satellite and algorithm-generated primary production data, calculated POC fluxes out of the euphotic layer and POC fluxes measured by sediment traps at the mesopelagic and bathypelagic layers during a one year period, with an ultimate goal to obtain a better understanding of the functioning of the biological pump in the SES. Annual particulate primary production based on satellite estimations (SeaWiFS) at the three sites, averages 205, 145 and 225 gC m- 2 y- 1 at the WMED, EMED and BS, respectively. According to our findings, the fraction of primary production that is exported out of the euphotic zone in the SES ranges between 4.2% and 11.4%, while the fraction reaching the mesopelagic layer (1000-1400 m depth) ranges between 0.6% and 1.8%. Finally, the fraction of primary production exported at the bathypelagic layer (2000-2800 m depth) is found to be 0.6%, 0.3% and 1.4% in the WMED, EMED and BS, respectively. The role of various processes responsible for the replenishment of surface waters with nutrients, giving rise to productivity episodes and organic carbon export to depth at the three SES sites is considered.

  9. Open-source feature-tracking algorithm for sea ice drift retrieval from Sentinel-1 SAR imagery

    NASA Astrophysics Data System (ADS)

    Muckenhuber, Stefan; Andreevich Korosov, Anton; Sandven, Stein

    2016-04-01

    A computationally efficient, open-source feature-tracking algorithm, called ORB, is adopted and tuned for sea ice drift retrieval from Sentinel-1 SAR (Synthetic Aperture Radar) images. The most suitable setting and parameter values have been found using four Sentinel-1 image pairs representative of sea ice conditions between Greenland and Severnaya Zemlya during winter and spring. The performance of the algorithm is compared to two other feature-tracking algorithms, namely SIFT (Scale-Invariant Feature Transform) and SURF (Speeded-Up Robust Features). Having been applied to 43 test image pairs acquired over Fram Strait and the north-east of Greenland, the tuned ORB (Oriented FAST and Rotated BRIEF) algorithm produces the highest number of vectors (177 513, SIFT: 43 260 and SURF: 25 113), while being computationally most efficient (66 s, SIFT: 182 s and SURF: 99 s per image pair using a 2.7 GHz processor with 8 GB memory). For validation purposes, 314 manually drawn vectors have been compared with the closest calculated vectors, and the resulting root mean square error of ice drift is 563 m. All test image pairs show a significantly better performance of the HV (horizontal transmit, vertical receive) channel due to higher informativeness. On average, around four times as many vectors have been found using HV polarization. All software requirements necessary for applying the presented feature-tracking algorithm are open source to ensure a free and easy implementation.

  10. Vertical velocities associated with deep open-ocean convection in the Northwestern Mediterranean Sea as indirectly observed by gliders

    NASA Astrophysics Data System (ADS)

    Bosse, Anthony; Testor, Pierre; Legland, Guillaume; Mortier, Laurent; Houpert, Loïc; Prieur, Louis

    2014-05-01

    During winter 2012-2013, deep open-ocean convection occurred in the Gulf of Lions (Northwestern Mediterranean Sea) and has been thoroughly documented thanks to the deployment of several gliders at the same time, Argo profiling floats, dedicated ship cruises, and a mooring located within the mixed patch. The data collected represent an unprecedented density of profiles during a event of open-ocean deep convection. We applied a method able to infer the vertical velocity signal from the glider navigation data. During active phase of mixing, the gliders faced significant vertical velocities (upward and downward displacement stronger than 10cm/s). Moving along a saw-tooth trajectory between the surface and 1000m, they could cross small scale convective plumes (L~1km) over a dive or ascent (2km and 2h between the surface and maximum depth), while recording temperature and salinity, as well as biogeochemical properties (dissolved oxygen, fluorescence, turbidity, ...). Our study provides a comprehensive dataset to get a characterization of convective plumes and a deeper understanding of their role in deep open-ocean convection.

  11. Ginger root against seasickness. A controlled trial on the open sea.

    PubMed

    Grøntved, A; Brask, T; Kambskard, J; Hentzer, E

    1988-01-01

    In a double-blind randomized placebo trial, the effect of the powdered rhizome of ginger (Zingiber officinale) was tested on seasickness. Eighty naval cadets, unaccustomed to sailing in heavy seas reported during voyages on the high seas, symptoms of seasickness every hour for 4 consecutive hours after ingestion of 1 g of the drug or placebo. Ginger root reduced the tendency to vomiting and cold sweating significantly better than placebo did (p less than 0.05). With regard to vomiting, a modified Protection Index (PI) = 72% was calculated. Remarkably fewer symptoms of nausea and vertigo were reported after ginger root ingestion, but the difference was not statistically significant. For all symptom categories, PI = 38% was calculated. PMID:3277342

  12. Progressive changes in rifting directions in the Campania margin (Italy): New constrains for the Tyrrhenian Sea opening

    NASA Astrophysics Data System (ADS)

    Milia, Alfonsa; Torrente, Maurizio Maria; Massa, Bruno; Iannace, Pietro

    2013-10-01

    Current models for the opening of the Tyrrhenian Sea invoke a unique extension vector throughout the rift to drift process, accommodated by margin parallel faults, but the role of the Campania margin faults in the opening of the Tyrrhenian back-arc basin is still poorly constrained. Gaeta Bay, located on the Campania margin, was investigated through the interpretation of seismic reflection and borehole data together with a stratigraphic correlation of dated outcropping units. The interpretation of a seismic grid using seismic and sequence stratigraphy and structural geology approaches in a dedicated GIS environment led to the generation of 2-D models of relevant geological surfaces, isochron maps, a 3-D digital model of the subsurface and to the reconstruction of the geological evolution of the margin with a resolution of 100 ka. Gaeta Bay is formed by three basins (northern, central and southern) and features a complex stratigraphic architecture: in the northern and central basins a syn-rift deposit (unit PP) is buried by the oldest aggradational deposit (unit A) that fills the accommodation space; a post 0.7 Ma succession (units B and C) filled the northern basin with a lateral aggradational geometry; a syn-tectonic wedge (unit B) was deposited in the central basin between 0.7 and 0.4 Ma; post 0.4 Ma thick deposits (unit C) are testimony to the collapse of the southern basin. A correlation between the geology of the bathyal basin and that of the Campania margin was established using a CROP seismic section that extended from the Vavilov basin to Gaeta Bay. Based on original and literature data we propose a kinematic evolution of the Tyrrhenian Sea upper plate over the last 10 Ma. This evolution consists of older extensional events (stages 1-2) off Sardinia and in the Vavilov basin (leaving the Campania margin unaffected). Younger events (stages 3-5) developed in the eastern (with a Pliocene-Quaternary change of the extension direction along the Campania Margin

  13. Geological significance of sediment provenance change in Taiwan Cenozoic sequences during opening of South China Sea (Invited)

    NASA Astrophysics Data System (ADS)

    Huang, C.; Yan, Y.; Lan, Q.

    2013-12-01

    During opening of the South China Sea, a stratigraphic hiatus associated with a slumping interval and changes of sediment geochemistry occurs in 25-27 Ma in ODP core of Site 1148 (Wang et al., 1999). This event was considered to be driven by the C7 MOR jump (Briais et al., 1993; Wang and Li, 2009). Study on detrital zircon ages in sandstones of the Taiwan Cenozoic sequence indicates a significant change of sediment provenance occurred at 24 Ma. The data indicate that the Cathaysian Block in SE China continuously provides sediments (predominant Mesozoic Yenshanian volcanics and granites) via the Minjiang drainage system to Taiwan throughout the Cenozoic. However, the Yangtze Block in Central China starts to contribute sediments to Taiwan since the Early Miocene (~24 Ma) as indicated by additional occurrences of 1500-2000 Ma and ~2500 Ma age peaks of detrital zircon grains. Contributions of these older detrital zircons from the Yangtze Block are consistent with occurrences of much abundant metamorphic minerals, like kyanite, epidote, staurolite and garnet, in the Miocene post-rift sequence of Taiwan and wide exposures of Achaean and Proterozoic metamorphic rocks in the Yangtze River drainage area. This suggests that the Yangtze River might initiate at ~24 Ma. In addition, sedimentology study further shows predominant braided river sandstones, fine conglomerates and coal measures in Taiwan Eocene syn-rift strata. This reveals that during the Eocene time the elevation in SE China-Taiwan area was much higher than the Present. This implies that the present east-tilting China geomorphology has not occurred until the Miocene/Oligocene boundary near 24 Ma. This 24 Ma event of provenance change in Taiwan Cenozoic sequences coincides with multiple tecto-stratigrahic events in Asia: a) stratigraphic hiatus, slumping, deepening of Miocene post-rift basins, changes of sediment geochemistry and C7 MOR jumping in the South China Sea, b) rapid exhumation of the Kuluan Mountain and

  14. Crustal architecture of the eastern margin of Japan Sea: back-arc basin opening and contraction

    NASA Astrophysics Data System (ADS)

    No, T.; Sato, T.; Takahashi, N.; Kodaira, S.; Kaneda, Y.; Ishiyama, T.; Sato, H.

    2012-12-01

    Although large earthquakes such as the 1964 Niigata earthquake (M 7.5), 1983 Nihonkai-Chubu earthquake (M 7.8), and 1993 Hokkaido Nansei-Oki earthquake (M 7.8) have caused large amounts of damage to the eastern margin of the Japan Sea, a substantial number of seismic studies have been conducted for the seismogenic zone on the Pacific Ocean side of Japan. In addition, the detail of the source fault model for the eastern margin of the Japan Sea is not well defined for all cases. This highlights the need for further studies to investigate seismic imaging. Therefore, we have collaborated with other Japanese research institutions for a project titled "Priority Investigations of Strain Concentration Areas" (which is funded by Special Coordination Funds for Promoting Science and Technology, Japan). This project has conducted seismic surveys from 2009 to 2012 using the deep-sea research vessel, Kairei, from the Japan Agency for Marine-Earth Science and Technology. There is a strain concentration area in the eastern part of the survey area (Okamura et al., 1995). The western part of the survey area includes the Yamato Basin and Japan Basin. It is very important to study the crustal structure in the seismotectonic studies of the eastern margin of the Japan Sea. We conducted a marine seismic survey by using a multichannel seismic (MCS) system and ocean bottom seismographs (OBSs) along the eastern margin of the Japan Sea. Seismic data were acquired along 42 lines with a total length of approximately 9,000 km. The following results were obtained from seismic imaging. On the basis of the results of the MCS imaging, active reverse faults and folds were observed in the margin of the Toyama Trough; however, the sedimentary layers in the trough were flat. In the sedimentary layers and crusts of the Sado Ridge, Mogami Trough, and source area of the 1964 Niigata earthquake located north of the Sado Island, greater deformation was observed. The deformation weakened toward the Yamato

  15. Zooplankton data: Vertical distributions of zooplankton in the Norweigian and Greenland Seas during summer, 1989

    SciTech Connect

    Lane, P.V.Z.; Smith, S.L.; Schwarting, E.M.

    1993-08-01

    Recent studies of zooplankton populations in the Greenland Sea have focused on processes at the Marginal Ice Zone (MIZ) and the areas immediately adjacent to it under the ice and in open water. These studies have shown a relatively short period of intense secondary productivity which is closely linked temporally and spatially to phytoplankton blooms occurring near the ice edge in spring and early summer. During the summer of 1989 we participated in a project focusing on benthic and water column processes in the basins of the Norwegian and Greenland Seas. This study allowed us to compare biological processes at the MIZ with those occurring in the open waters of the Greenland Sea, and to compare processes at both of these locations with those in the Norwegian Sea. The data presented in this report are the results of zooplankton net tows covering the upper 1000 meters of the water column over the Norwegian Sea basin and the Greenland Sea basin, and the upper 500 meters of open water adjacent to the MIZ in the Greenland Sea. Sampling was conducted between 12 and 29 July 1989.

  16. Two decades and counting: 24-years of sustained open ocean biogeochemical measurements in the Sargasso Sea

    NASA Astrophysics Data System (ADS)

    Lomas, M. W.; Bates, N. R.; Johnson, R. J.; Knap, A. H.; Steinberg, D. K.; Carlson, C. A.

    2013-09-01

    The Bermuda Atlantic Time-series Study (BATS) program has sampled the northwestern Sargasso Sea on a biweekly (January to April) to monthly basis since October 1988. The primary objective of the core BATS program continues to be an improved understanding of the time-variable processes and mechanisms that control the biogeochemical cycling of carbon and related elements in the surface ocean. With 24 years of measurements for most chemical, physical and biological variables, we have moved beyond descriptions of seasonal and interannual variability to examination of multi-year trends and potential controls, however there remain substantial gaps in our knowledge of the ecosystem mechanisms related to organic matter production, export and remineralization. While earlier BATS overviews have focused on describing seasonal and year-to-year variability, this overview provides new information on three long-standing biogeochemical questions in Sargasso Sea biogeochemistry. First, why is there a discrepancy between biological (i.e., sediment trap) and geochemical estimates of carbon export production? Winter storms and mesoscale eddies have now been clearly shown to contribute to annual nutrient budgets and carbon export production. Recent information on phytoplankton natural isotopic nitrogen composition, and data from profiling floats suggests that small phytoplankton are important contributors to new production in summer despite the apparent absence of a mechanism to entrain nitrate into the euphotic zone. These findings aid in closing the gap between these two different estimates of carbon export production. Second, what supports the seasonal drawdown of carbon dioxide in the absence of detectable nutrients? The zooplankton timeseries at BATS highlights the importance of zooplankton as a conduit for carbon removal due to grazing and vertical migration. Although increases in cellular elemental stoichiometry to values greater than the canonical Redfield Ratio, and the

  17. Full-fit reconstruction of opening of Labrador Sea and Baffin Bay: A special focus on continental deformation

    NASA Astrophysics Data System (ADS)

    Hosseinpour, M.; Müller, R.; Williams, S.

    2012-12-01

    Reconstructing the pre-rift configuration of Greenland and North America, and the early tectonic evaluation within the Labrador Sea and Baffin Bay, raises several issues. Some models treat linear magnetic anomalies adjacent to the continental margins of the Labrador Sea as 28-33 seafloor-spreading isochrones. However, more recent seismic data suggest that so-called "transitional crust" extends much further seaward. In addition, various authors have proposed that treating Greenland and North America as rigid plates leads to unreasonable gaps and overlaps in full-fit reconstructions. Extension within Hudson Bay, or large strike-slip motions within Greenland, has been suggested as possible explanations. To address these issues, we investigate the full-fit configuration of Greenland and North America using an approach that considers continental deformation in a quantitative manner, in contrast to traditional models that treat continents as rigid blocks. This new method has been applied in this region to derive new poles of rotation for full-fit plate reconstruction. This method takes in to account the landward limit of thinning and extension in continental crust of the rift margins. We first generate a crustal thickness map using a gravity inversion method, calibrated against all available crustal thickness information from seismic refraction profiles and receiver functions from onshore seismic stations. We also define the extent of the limit of stretched continental crust along each margin. The continental-oceanic boundary (COB) is located using interpreted seismic profiles and revising COBs previously proposed for both margins. Restoration of COBs was accomplished by generating small circle motion paths between UCCL and COB lines. Crustal thickness was extracted along each profile to calculate its length before subjected to stretching. Major corrections in the extent of stretched continental crust, and it's pre-rift thickness were taken into account to achieve the

  18. Hypotheses to explain high-nutrient conditions in the open sea

    SciTech Connect

    Cullen, J.J. )

    1991-12-01

    Ocean high-nutrient, low-chlorophyll waters are characterized principally by the persistence of major nutrients at the sea surface. This condition indicates control of autotrophic production by something other than NO{sub 3} or PO{sub 4}, but the nature of this control is at present unresolved. The range of hypotheses to explain the high-nutrient condition is illustrated by the grazing hypothesis (specific growth rates of phytoplankton are maximal and environmental stability allows development of a balanced food web that maintains low standing crops of phytoplankton) and the iron hypothesis (standing crop of plankton is constrained by availability of Fe: if more Fe were available, the standing crop of phytoplankton would increase and NO{sub 3} would be depleted, despite grazing). The iron hypothesis has been examined experimentally in the subarctic and equatorial Pacific and in Antarctic waters. In each environment, Fe enrichment enhanced the field yield of phytoplankton and that enrichment of high-nutrient waters with Fe would change the species composition of phytoplankton and food-web interactions, thereby enhancing utilization of NO{sub 3}. The magnitude of this enhancement cannot be predicted with confidence.

  19. Toxicity assessment of atmospheric particulate matter in the Mediterranean and Black Seas open waters.

    PubMed

    Mesquita, Sofia R; Dachs, Jordi; van Drooge, Barend L; Castro-Jiménez, Javier; Navarro-Martín, Laia; Barata, Carlos; Vieira, Natividade; Guimarães, Laura; Piña, Benjamin

    2016-03-01

    Atmospheric deposition of particulate matter (PM) is recognized as a relevant input vector for toxic compounds, such as polycyclic aromatic hydrocarbons (PAHs), into the marine environment. In this work we aimed to analyse the biological activity and potential adverse effects of PM constituents to aquatic organisms. Organic extracts of atmospheric PM samples from different sub-basins of the Mediterranean and Black Seas were screened using different toxicological tests. A yeast-based assay (AhR-RYA) revealed that dioxin-like activity correlated with the concentration of total PAHs in the PM samples, as well as with their predicted toxic equivalent values (TEQs). Although the zebrafish embryotoxicity test (the ZET assay) showed no major phenotypical adverse effects, up-regulation of mRNA expression of cyp1a, fos and development-related genes (previously described as related to PM toxicity) was observed in exposed embryos when compared to controls. Results showed that mRNA patterns of the studied genes followed a similar geographic distribution to both PAH content and dioxin-like activity of the corresponding extracts. The analysis also showed a distinct geographical pattern of activation of pancreatic markers previously related to airborne pollution, probably indicating a different subset of uncharacterized particle-bound toxicants. We propose the combination of the bioassays tested in the present study to be applied to future research with autochthonous species to assess exposure and potential toxic effects of ambient PM. The present study emphasizes the need for more in-depth studies into the toxic burden of atmospheric PM on aquatic ecosystems, in order to improve future regulatory guidelines. PMID:26745302

  20. Seasonal dynamics of circulation in Hooghly Estuary and its adjacent coastal oceans

    NASA Astrophysics Data System (ADS)

    Mishra, Shashank Kr.; Nayak, Gourav; Nayak, R. K.; Dadhwal, V. K.

    2016-05-01

    Hooghly is one of the major estuaries in Ganges, the largest and longest river in the Indian subcontinent. The Hooghly estuary is a coastal plain estuary lying approximately between 21°-23° N and 87°-89° E. We used a terrain following ocean model to study tide driven residual circulations, seasonal mean flow patterns and its energetics in the Hooghly estuary and adjacent coastal oceans on the north eastern continental shelf of India. The model is driven by tidal levels at open ocean end and winds at the air-sea interface. The sources of forcing fields for tides were from FES2012, winds from ECMWF. Harmonic analysis is carried out to compute the tidal and non-tidal components of currents and sea level from the model solutions. The de-tidal components were averaged for the entire period of simulation to describe residual and mean-seasonal circulations in the regions. We used tide-gauge, SARAL-ALTIKA along track sea level measurements to evaluate model solutions. Satellite measure Chla were used along with simulated currents to describe important features of the circulations in the region.

  1. Exercise-induced intrapulmonary shunting of venous gas emboli does not occur after open-sea diving.

    PubMed

    Dujić, Zeljko; Palada, Ivan; Obad, Ante; Duplancić, Darko; Brubakk, Alf O; Valic, Zoran

    2005-09-01

    Paradoxical arterializations of venous gas emboli can lead to neurological damage after diving with compressed air. Recently, significant exercise-induced intrapulmonary anatomical shunts have been reported in healthy humans that result in widening of alveolar-to-arterial oxygen gradient. The aim of this study was to examine whether intrapulmonary shunts can be found following strenuous exercise after diving and, if so, whether exercise should be avoided during that period. Eleven healthy, military male divers performed an open-sea dive to 30 m breathing air, remaining at pressure for 30 min. During the bottom phase of the dive, subjects performed mild exercise at approximately 30% of their maximal oxygen uptake. The ascent rate was 9 m/min. Each diver performed graded upright cycle ergometry up to 80% of the maximal oxygen uptake 40 min after the dive. Monitoring of venous gas emboli was performed in both the right and left heart with an ultrasonic scanner every 20 min for 60 min after reaching the surface pressure during supine rest and following two coughs. The diving profile used in this study produced significant amounts of venous bubbles. No evidence of intrapulmonary shunting was found in any subject during either supine resting posture or any exercise grade. Also, short strenuous exercise after the dive did not result in delayed-onset decompression sickness in any subject, but studies with a greater number of participants are needed to confirm whether divers should be allowed to exercise after diving. PMID:15845772

  2. 78 FR 14411 - Notice of Proposed Policy Clarification Concerning Designation of Adjacent Coastal States for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-05

    ... provided.\\23\\ \\22\\ 40 FR 52401 (Nov. 10, 1975). \\23\\ See 33 CFR 2.1(a) (``The purpose of this part is to... internal waters, to a belt of sea adjacent to its coast, described as a territorial sea.'' \\10\\ Article...

  3. Particle-water partitioning of PCBs in the photic zone: a 25-month study in the open Baltic Sea.

    PubMed

    Sobek, Anna; Gustafsson, Orjan; Hajdu, Susanna; Larsson, Ulf

    2004-03-01

    From previous laboratory and field studies, it remains unclear whether partitioning of hydrophobic organic contaminants (HOCs) to phytoplankton from water is kinetically limited or may be treated as an equilibrium process. Here, we report on the partitioning of polychlorinated biphenyls (PCBs) to particulate organic carbon (POC), dominated by planktonic primary production, in the open Baltic Sea during a 25-month period. The organic carbon-normalized partition coefficient (Koc) was corrected for temperature, salinity, and sorption to filter-passing organic carbon. At all 21 sampling occasions, the log Koc-log Kow regression was significantly linear, despite a large variation in biogeochemical parameters such as POC concentration and composition, primary production, and phytoplankton species composition. These data strongly suggest that partitioning of PCBs to POC in temperate surface waters is equilibrated and therefore not kinetically limited by factors such as rapid phytoplankton growth rate or large cell size. The partitioning of PCBs to the POC was described throughout seasonal cycles by log Koc = 0.88 +/- 0.07 log Kow + 0.90 +/- 0.47 (95% confidence interval). The slope of the log Koc-log Kow regression for the single sampling occasions varied between 0.56 and 1.25, and there was a seasonal variation in the POC sorbent quality (e.g., log Koc for PCB 28 varied between 5.5 and 6.9; median 5.9). These variations reflect the variability in structural composition of the POC pool in such pelagic waters. Being able to predict particle-water partitioning of HOCs significantly reduces the required complexity of both food web uptake models and predictions of POC-mediated export of HOCs to the deep ocean. PMID:15046338

  4. The Terror Bank (Scotia Sea, Antarctica): a remnant part of the stretched Antarctic passive margin of the Drake Passage opening

    NASA Astrophysics Data System (ADS)

    Suriñach, E.

    2009-04-01

    During January-February 2008, in the frame of the IPY, two geophysical profiles 500 km long were recorded in the Drake Passage along spreading corridors between transform faults in the southern flank of West Scotia Ridge. The profiles cross the oldest oceanic crust, the Terror Bank and the oceanic Protector Basin. The survey carried out on board the R/V Hespérides includes swath bathymetry, ultra-high resolution seismics, multichannel seismic reflection, gravity and magnetic data. Our aim was to unravel the enigma of the missing conjugate passive antarctic margin. Both profiles provide evidence of the continental nature of the Terror Bank, which is an NNE-SSW elongated high, at 2000 m depth, surrounded by the Scotia and Protector abyssal plains exceeding 3000 m depth. The Terror Bank is limited by asymmetrical slopes with NW smooth and SE sharp margins. The sedimentary record shows many erosive (channels, moats, scours, etc) and depositional (drifts with superimposed sedimentary waves) features related to the water mass circulation. Minima values of the Bouguer anomaly point to the thinned continental nature of the Terror Bank. Several half grabens bounded by north-westwards dipping faults and with sedimentary wedges, exceeding 1 km thickness, thickening south-eastwards, suggest that the initial stage of rifting was followed by an oceanic spreading axis located north-westwards. Moreover, linear sea-floor magnetic anomalies indicate that oldest chrons are placed to the west, pointing to an eastward propagation of the oceanic spreading since the initial stages of the Scotia Arc development. The new data allow us to constrain the tectonic evolution of the Oligocene initial opening stages of the Drake Passage oceanic gateway and its paleoceanographic evolution. This research was supported by the Spanish Ministerio de Educación y Ciencia projects: POL2006-13836-C03-01 and CGL2004-05646.

  5. The dynamics of back-arc extension: an experimental approach to the opening of the Tyrrhenian Sea

    NASA Astrophysics Data System (ADS)

    Faccenna, Claudio; Davy, Philippe; Brun, Jean-Pierre; Funiciello, Renato; Giardini, Domenico; Mattei, Massimo; Nalpas, Thierry

    1996-09-01

    The E-W-opening Tyrrhenian Sea developed after the Cretaceous-Palaeogene Alpine collision, nearly perpendicular to the motion of the African plate, as a back-arc of the Adria-Ionian westward subduction. Three driving mechanisms have been proposed to explain the dynamic evolution of the Tyrrhenian-Apennine system: (1) the northward indentation of the African plate; (2) the retreating subduction of the Adria-Ionian lithosphere; and (3) the gravitational collapse of the Alpine post-collisional wedge. In order to define the relative contribution of each of these mechanisms in the Neogene dynamic of the Tyrrhenian-Apennine system, we performed 3-D laboratory experiments, in which we simulated a retreating subduction process in a compressional regime oriented perpendicularly to the direction of subduction; in this framework we also tested the influence of the gravitational collapse of the overriding plate. Experiments were constructed using dry sand and silicone putties to simulate brittle upper crust and ductile lower crust/upper mantle, respectively; these layers floated on a high-density, low-viscosity glucose syrup which simulated the asthenosphere. The main conclusion of our experiments is that large-scale continental extension, similar to that observed in the Tyrrhenian area, could be reproduced perpendicular to the shortening direction induced by the indentation of the African plate; in this framework, extensional processes are indeed possible if the trench retreat velocity is higher than the rate of shortening induced by the advancing African plate. Our experimental results indicate that this high trench retreat velocity could be explained by the coexistence of the gravitational collapse of the post-Alpine wedge with a slab-pull process, linked to the retreating subduction of the Adria-Ionian plate. While the first mechanism is predominant in the Northern Tyrrhenian area, the second one seems to be important in the latest stage of extension and oceanic accretion

  6. [Phytoplankton pigment patterns and community structure in the Yangtze Estuary and its adjacent areas].

    PubMed

    Lai, Jun-xiang; Yu, Zhi-ming; Song, Xiu-xian; Han, Xiao-tian; Cao, Xi-hua; Yuan, Yong-quan

    2013-09-01

    Three cruises were carried out in the Yangtze Estuary and its adjacent areas in May, November, June during 2009-2010. The spatial variations of phytoplankton community structure were investigated based on RP-HPLC analysis of pigments and CHEMTAX processing of the pigment data. 21 kinds of pigments were detected, among which chlorophyll a, peridinin, fucoxanthin, 19'-butanoyloxyfucoxanthin, 19'-hexanoyloxyfucoxanthin, chlorophyll b, diadinoxanthin, alloxanthin and zeaxanthin were the major pigments in the Yangtze Estuary and its adjacent areas. Chlorophyll a was the most abundant in all pigments, followed by fuxoxanthin. Other pigments generally contributed a minor proportion to the total pigments. High concentrations of fucoxanthin and peridinin were observed in May 2009 and June 2010, indicating blooms of diatoms and dinoflagellates. The results showed that the composition and distribution of phytoplankton pigments were influenced by environmental factors. The phytoplankton community, as determined by biomarker pigment concentration using HPLC and CHEMTAX, was composed mainly of diatoms, dinoflagellates, cryptophytes, chlorophytes, cyanobacteria, prymnesiophytes, chrysophytes and prasinophytes. The dominant algal groups were diatoms, dinoflagellates and chlorophytes in May 2009. The phytoplankton community was characterized by high contribution of diatoms in November 2009. Diatoms, dinoflagellates and cryptophytes accounted for 62.5% of chlorophyll a in June 2010, and the relative abundance of cyanobacteria was higher in this cruise. The spatial variations of phytoplankton community structure featured distinct regionality. Diatoms, chlorophytes and cryptophytes were the main groups in the inshore waters, and the abundances of prymnesiophytes, chrysophytes and cyanobacteria were increasing from inshore to the open sea. PMID:24288983

  7. Modelling the interannual variability (1979-2012) of the Mediterranean open-sea deep convection using a coupled regional climate system model

    NASA Astrophysics Data System (ADS)

    Somot, Samuel; Testor, Pierre; Durrieu de Madron, Xavier; Houpert, Loic; Herrmann, Marine; Dubois, Clotilde; Sevault, Florence

    2013-04-01

    The North-Western Mediterranean Sea is known as one of the only place in the world where open-sea deep convection occurs (often up to more than 2000m) with the formation of the Western Mediterranean Deep Water (WMDW). This phenomena is mostly driven by local preconditioning of the water column and strong buoyancy losses during Winter. At the event scale, the WMDW formation is characterized by different phases (preconditioning, strong mixing, restratification and spreading), intense air-sea interaction and strong meso-scale activity but, on a longer time scale, it also shows a large interannual variability and may be strongly affected by climate change with impact on the regional biogeochemistry. Therefore simulating and understanding the temporal variability of the North-Western Mediterranean open-sea deep convection is considered as quite a challenging task for the ocean and climate modelling community. Achieving such a goal requires to work with high resolution models for the ocean and the atmosphere interacting freely and to run long-term and temporally homogeneous simulations with a realistic chronology. In agreement with this statement, we developed at Meteo-France / CNRM a Mediterranean Regional Climate System Model (RCSM) that includes high-resolution representation of the regional atmosphere, land surface, rivers and ocean. The various components are respectively ALADIN (50 km), ISBA (50 km), TRIP (50 km) and NEMO-MED8 (10 km). All the components are interactively coupled daily and a simulation over the period 1979-2012 has been performed using the atmosphere ERA-Interim reanalysis and the ocean NEMOVAR1° reanalysis as 3D lateral-boundary conditions. Spectral nudging technique is applied in the atmosphere. We first evaluate the ability of this model to simulate some of the observed WMDW formation events (air-sea flux, timing, water mass characteristics, deep water formation rate) thanks to the large observational efforts recently carried out to better

  8. Seasonal variability of the Red Sea, from GRACE time-variable gravity and altimeter sea surface height measurements

    NASA Astrophysics Data System (ADS)

    Wahr, John; Smeed, David; Leuliette, Eric; Swenson, Sean

    2014-05-01

    Seasonal variability of sea surface height and mass within the Red Sea, occurs mostly through the exchange of heat with the atmosphere and wind-driven inflow and outflow of water through the strait of Bab el Mandab that opens into the Gulf of Aden to the south. The seasonal effects of precipitation and evaporation, of water exchange through the Suez Canal to the north, and of runoff from the adjacent land, are all small. The flow through the Bab el Mandab involves a net mass transfer into the Red Sea during the winter and a net transfer out during the summer. But that flow has a multi-layer pattern, so that in the summer there is actually an influx of cool water at intermediate (~100 m) depths. Thus, summer water in the southern Red Sea is warmer near the surface due to higher air temperatures, but cooler at intermediate depths (especially in the far south). Summer water in the northern Red Sea experiences warming by air-sea exchange only. The temperature profile affects the water density, which impacts the sea surface height but has no effect on vertically integrated mass. Here, we study this seasonal cycle by combining GRACE time-variable mass estimates, altimeter (Jason-1, Jason-2, and Envisat) measurements of sea surface height, and steric sea surface height contributions derived from depth-dependent, climatological values of temperature and salinity obtained from the World Ocean Atlas. We find good consistency, particularly in the northern Red Sea, between these three data types. Among the general characteristics of our results are: (1) the mass contributions to seasonal SSHT variations are much larger than the steric contributions; (2) the mass signal is largest in winter, consistent with winds pushing water into the Red Sea through the Strait of Bab el Mandab in winter, and out during the summer; and (3) the steric signal is largest in summer, consistent with summer sea surface warming.

  9. 46 CFR 148.445 - Adjacent spaces.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Adjacent spaces. 148.445 Section 148.445 Shipping COAST... THAT REQUIRE SPECIAL HANDLING Additional Special Requirements § 148.445 Adjacent spaces. When... following requirements must be met: (a) Each space adjacent to a cargo hold must be ventilated by...

  10. 46 CFR 148.445 - Adjacent spaces.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Adjacent spaces. 148.445 Section 148.445 Shipping COAST... THAT REQUIRE SPECIAL HANDLING Additional Special Requirements § 148.445 Adjacent spaces. When... following requirements must be met: (a) Each space adjacent to a cargo hold must be ventilated by...

  11. 46 CFR 148.445 - Adjacent spaces.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Adjacent spaces. 148.445 Section 148.445 Shipping COAST... THAT REQUIRE SPECIAL HANDLING Additional Special Requirements § 148.445 Adjacent spaces. When... following requirements must be met: (a) Each space adjacent to a cargo hold must be ventilated by...

  12. 46 CFR 148.445 - Adjacent spaces.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Adjacent spaces. 148.445 Section 148.445 Shipping COAST... THAT REQUIRE SPECIAL HANDLING Additional Special Requirements § 148.445 Adjacent spaces. When... following requirements must be met: (a) Each space adjacent to a cargo hold must be ventilated by...

  13. The European Fixed point Open Ocean Observatory network (FixO3): Multidisciplinary observations from the air-sea interface to the deep seafloor

    NASA Astrophysics Data System (ADS)

    Lampitt, Richard; Cristini, Luisa; Alexiou, Sofia

    2015-04-01

    The Fixed point Open Ocean Observatory network (FixO3, http://www.fixo3.eu/ ) integrates 23 European open ocean fixed point observatories and improves access to these infrastructures for the broader community. These provide multidisciplinary observations in all parts of the oceans from the air-sea interface to the deep seafloor. Started in September 2013 with a budget of 7 Million Euros over 4 years, the project has 29 partners drawn from academia, research institutions and SME's coordinated by the National Oceanography Centre, UK. Here we present the programme's achievements in the 18 months and the activities of the 12 Work Packages which have the objectives to: • integrate and harmonise the current procedures and processes • offer free access to observatory infrastructures to those who do not have such access, and free and open data services and products • innovate and enhance the current capability for multidisciplinary in situ ocean observation Open ocean observation is a high priority for European marine and maritime activities. FixO3 provides important data and services to address the Marine Strategy Framework Directive and in support of the European Integrated Maritime Policy. FixO3 provides a strong integrated framework of open ocean facilities in the Atlantic from the Arctic to the Antarctic and throughout the Mediterranean, enabling an integrated, regional and multidisciplinary approach to understand natural and anthropogenic change in the ocean.

  14. From Sea to Shining Sea

    ERIC Educational Resources Information Center

    Scott, Beverly

    2005-01-01

    Deep down in the depths of the sea, beautiful fish, mysterious ocean life, and unusual plants glimmer and glow in the eerie atmosphere of an ever-changing ocean. This article describes how, with this vision and a purpose in mind, three teachers pulled open classroom walls and joined forces so their second graders could create a mammoth 30 x 75"…

  15. Hierarchy and sea ice mechanics: A case study from the Beaufort Sea

    NASA Astrophysics Data System (ADS)

    Overland, James E.; Walter, Bernard A.; Curtin, Thomas B.; Turet, Philip

    1995-03-01

    Hierarchy implies that the study of sea ice can be divided into analysis of subsets of processes based on scale and their interaction with adjacent scales. We apply these concepts to regional sea ice dynamics. The apparent self-similar property of ice floes seen in aircraft or satellite images argues for an aggregate nature of sea ice, that viscouslike regional behavior arises from discrete floe interactions. However, for some regions and some times, characteristic behavior, where lead patterns seen in basin-wide advanced very high resolution radiometer images appear to be related to coastal orientation hundreds of kilometers away, suggests that small regional scale processes O(10 km) and discontinuities in the velocity or stress state along boundaries can affect the larger-scale sea ice distribution and dynamics O(500 km). Thus sea ice displays both aggregate type behavior and discontinuous type behavior based on the history of forcing and shape of the enclosing basin. The appropriate matching of atmospheric processes to sea ice processes in air-ice interaction is through the sea ice deformation field rather than the response of ice velocity to the local wind. This is because atmospheric forcing and sea ice deformation have matching energetic scales at several hundred kilometers and timescales of days. An example of northerly winds during the April 1992 Arctic Leads Experiment period suggests discontinuous type behavior upwind of the Alaska coast followed by a general opening behavior with easterly winds. There appear to be natural scale divisions between climate scale sea ice processes of O(100-300 km) which resolve aggregate behavior, regional scale O(10-50 km) which is necessary to resolve observed shearing behavior, and the floe scale O(1 km). Because the climate scale is two levels removed from the floe scale, care must be exercised in using ice properties from the floe scale in climate scale models; ice strength is an example of such a scale dependent

  16. Openings

    PubMed Central

    Selwyn, Peter A.

    2015-01-01

    Reviewing his clinic patient schedule for the day, a physician reflects on the history of a young woman he has been caring for over the past 9 years. What starts out as a routine visit then turns into a unique opening for communication and connection. A chance glimpse out the window of the exam room leads to a deeper meditation on parenthood, survival, and healing, not only for the patient but also for the physician. How many missed opportunities have we all had, without even realizing it, to allow this kind of fleeting but profound opening? PMID:26195687

  17. Openings.

    PubMed

    Selwyn, Peter A

    2015-01-01

    Reviewing his clinic patient schedule for the day, a physician reflects on the history of a young woman he has been caring for over the past 9 years. What starts out as a routine visit then turns into a unique opening for communication and connection. A chance glimpse out the window of the exam room leads to a deeper meditation on parenthood, survival, and healing, not only for the patient but also for the physician. How many missed opportunities have we all had, without even realizing it, to allow this kind of fleeting but profound opening? PMID:26195687

  18. Reprint of: Carbon flux to the deep in three open sites of the Southern European Seas (SES)

    NASA Astrophysics Data System (ADS)

    Gogou, Alexandra; Sanchez-Vidal, Anna; Durrieu de Madron, Xavier; Stavrakakis, Spyros; Calafat, Antoni M.; Stabholz, Marion; Psarra, Stella; Canals, Miquel; Heussner, Serge; Stavrakaki, Ioanna; Papathanassiou, Evangelos

    2014-07-01

    In this study, we investigate the strength and efficiency of carbon sequestration in the Southern European Seas (SES), by analyzing the export of POC at three deep sites located in the Western Mediterranean Sea (WMED), the Eastern Mediterranean Sea (EMED) and the Black Sea (BS). We combine estimations of satellite and algorithm-generated primary production data, calculated POC fluxes out of the euphotic layer and POC fluxes measured by sediment traps at the mesopelagic and bathypelagic layers during a one year period, with an ultimate goal to obtain a better understanding of the functioning of the biological pump in the SES. Annual particulate primary production based on satellite estimations (SeaWiFS) at the three sites, averages 205, 145 and 225 gC m- 2 y- 1 at the WMED, EMED and BS, respectively. According to our findings, the fraction of primary production that is exported out of the euphotic zone in the SES ranges between 4.2% and 11.4%, while the fraction reaching the mesopelagic layer (1000-1400 m depth) ranges between 0.6% and 1.8%. Finally, the fraction of primary production exported at the bathypelagic layer (2000-2800 m depth) is found to be 0.6%, 0.3% and 1.4% in the WMED, EMED and BS, respectively. The role of various processes responsible for the replenishment of surface waters with nutrients, giving rise to productivity episodes and organic carbon export to depth at the three SES sites is considered.

  19. Spatio-temporal distributions of chlorofluorocarbons and methyl iodide in the Changjiang (Yangtze River) estuary and its adjacent marine area.

    PubMed

    Yuan, Da; Yang, Gui-Peng; He, Zhen

    2016-02-15

    Temporal and spatial distribution patterns of volatile halogenated organic compounds (VHOCs), such as dichlorodifluoromethane (CFC-12), trichlorofluoromethane (CFC-11), trichlorotrifluoroethane (CFC-113), and methyl iodide (CH3I), in the Changjiang (Yangtze River) estuary and its adjacent marine area were measured during two cruises from 21 February to 10 March 2014 and from 10 to 21 July 2014. VHOC concentrations showed seasonal variation with higher values during winter. VHOC distributions evidently decreased along the freshwater plume from the river mouth to the open sea and from inshore to offshore regions. VHOC distributions were obviously influenced by the Changjiang runoff, anthropogenic inputs, and biological release of phytoplankton. The study area was a net sink for CFC-12 and CFC-11, but a net source for atmospheric CH3I during the study periods. PMID:26707981

  20. Impact of adjacent land use on coastal wetland sediments.

    PubMed

    Karstens, Svenja; Buczko, Uwe; Jurasinski, Gerald; Peticzka, Robert; Glatzel, Stephan

    2016-04-15

    Coastal wetlands link terrestrial with marine ecosystems and are influenced from both land and sea. Therefore, they are ecotones with strong biogeochemical gradients. We analyzed sediment characteristics including macronutrients (C, N, P, K, Mg, Ca, S) and heavy metals (Mn, Fe, Cu, Zn, Al, Co, Cr, Ni) of two coastal wetlands dominated by Phragmites australis at the Darss-Zingst Bodden Chain, a lagoon system at the Southern Baltic Sea, to identify the impact of adjacent land use and to distinguish between influences from land or sea. In the wetland directly adjacent to cropland (study site Dabitz) heavy metal concentrations were significantly elevated. Fertilizer application led to heavy metal accumulation in the sediments of the adjacent wetland zones. In contrast, at the other study site (Michaelsdorf), where the hinterland has been used as pasture, heavy metal concentrations were low. While the amount of macronutrients was also influenced by vegetation characteristics (e.g. carbon) or water chemistry (e.g. sulfate), the accumulation of heavy metals is regarded as purely anthropogenic influence. A principal component analysis (PCA) based on the sediment data showed that the wetland fringes of the two study sites are not distinguishable, neither in their macronutrient status nor in their concentrations of heavy metals, whereas the interior zones exhibit large differences in terms of heavy metal concentrations. This suggests that seaside influences are minor compared to influences from land. Altogether, heavy metal concentrations were still below national precautionary and action values. However, if we regard the macronutrient and heavy metal concentrations in the wetland fringes as the natural background values, an accumulation of trace elements from agricultural production in the hinterland is apparent. Thus, coastal wetlands bordering croplands may function as effective pollutant buffers today, but the future development has to be monitored closely to avoid

  1. A modern analog for carbonate source-to-sink sedimentary systems: the Glorieuses archipelago and adjacent basin (SW Indian Ocean)

    NASA Astrophysics Data System (ADS)

    Jorry, S.; Jouet, G.; Prat, S.; Courgeon, S.; Le Roy, P.; Camoin, G.; Caline, B.

    2014-12-01

    This study presents the geomorphological and sedimentological analysis of a modern carbonate source-to-sink system located north of Madagascar (SW Indian Ocean). The sedimentary system is composed of an isolated carbonate platform sited on top of a seamount rising steeply from the seabed located at 3000 m water depth. The slope of the seamount is incised by canyons, and meandering channels occur above lobbed sedimentary bodies at the foot of the slope. The dataset consists of dredges, sediment piston cores, swath bathymetry and seismic (sparker and 2D high-resolution) lines collected from inner platform (less than 5 m deep) to the adjacent deep sedimentary basin. Particle size analysis and composition of carbonate grains are used to characterize the distribution and heterogeneity of sands accumulated on the archipelago. Main results show that composition of carbonate sediments is dominated by segments of Halimeda, large benthic foraminifera, coral debris, molluscs, echinoderms, bryozoans and sponges. According to the shape and the position of sandwaves and intertidal sandbars developed in the back-barrier reef, the present organization of these well-sorted fine-sand accumulations appears to be strongly influenced by flood tidal currents. Seismic lines acquired from semi-enclosed to open lagoon demonstrate that most of the sediment is exported and accumulated along the leeward margin of the platform, which is connected to a canyon network incising the outer slope. Following the concept of highstand shedding of carbonate platforms (Schlager et al., 1994), excess sediment is exported by plumes and gravity flows to the adjacent deep sea where it feeds a carbonate deep-sea fan. Combined observations from platform to basin allow to explain how the Glorieuses carbonate source to sink system has evolved under the influence of climate and of relative sea-level changes since the last interglacial.

  2. 33 CFR 2.22 - Territorial sea.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Territorial sea. 2.22 Section 2... Jurisdictional Terms § 2.22 Territorial sea. (a) With respect to the United States, the following apply— (1) Territorial sea means the waters, 12 nautical miles wide, adjacent to the coast of the United States...

  3. Biogenic aromatic hydrocarbon geochemistry in the Rhone river delta and in surface sediments from the open North-Western Mediterranean sea

    NASA Astrophysics Data System (ADS)

    Lipiatou, Elisabeth; Saliot, Alain

    1992-05-01

    The origin, evolution and transport of biogenic polycyclic aromatic hydrocarbons (PAH) were studied in the Rhone river delta and the Gulf of Lions (North-western Mediterranean). Sediments and riverborne suspended particulate matter were collected and analysed for PAH using a combination of high performance liquid chromatography (HPLC), gas chromatography (GC) and GC/mass spectrometry (GC/MS). Special attention was given to aromatic hydrocarbons from natural sources: retene and its precursors related to abietic acid found in the resins of conifers, and pentacyclic triterpenoids derived from α- and β-amyrins, constituents of terrestrial plants. Retene concentrations varied in the following ranges: 15-59 ng g -1 in river-borne particulate material, 20-70 ng g -1 in deltaic sediments, 3-16 ng g -1 in open-sea sediments. Retene precursor concentrations were generally higher than those of retene in the delta, whereas the inverse was observed in open-sea sediments. In these sediments the low concentrations or the absence of precursors suggested a predominant transport of pre-formed retene by aerosols and fine particles issued from the Rhone river. In the deltaic area, both retene and its precursors are transported by river waters from the forest runoff of the drainage basin. Transformation of precursors to retene occurred during transport by river waters and/or fast after deposition in surface deltaic sediments. Pentacyclic triterpenoid concentrations varied from 54 to 296 ng g -1 in deltaic sediments and from 0 to 21 ng g -1 in open-sea sediments. Concentrations of tetrahydrochrysenes (3,3,7-THC and 3,4,7-THC) decreased with increasing distance from the Rhone river mouth. The presence of THC in the riverine particulate matter (10-105 ng g -1) indicated that the degradation of terrestrial organic matter by microbial activity had begun before the deposition of particulate matter in the surface sediment. A good correlation was observed between ΣTHC and δ13C ( r2 = 0·89

  4. First day of an oil spill on the open sea: early mass transfers of hydrocarbons to air and water.

    PubMed

    Gros, Jonas; Nabi, Deedar; Würz, Birgit; Wick, Lukas Y; Brussaard, Corina P D; Huisman, Johannes; van der Meer, Jan R; Reddy, Christopher M; Arey, J Samuel

    2014-08-19

    During the first hours after release of petroleum at sea, crude oil hydrocarbons partition rapidly into air and water. However, limited information is available about very early evaporation and dissolution processes. We report on the composition of the oil slick during the first day after a permitted, unrestrained 4.3 m(3) oil release conducted on the North Sea. Rapid mass transfers of volatile and soluble hydrocarbons were observed, with >50% of ≤C17 hydrocarbons disappearing within 25 h from this oil slick of <10 km(2) area and <10 μm thickness. For oil sheen, >50% losses of ≤C16 hydrocarbons were observed after 1 h. We developed a mass transfer model to describe the evolution of oil slick chemical composition and water column hydrocarbon concentrations. The model was parametrized based on environmental conditions and hydrocarbon partitioning properties estimated from comprehensive two-dimensional gas chromatography (GC×GC) retention data. The model correctly predicted the observed fractionation of petroleum hydrocarbons in the oil slick resulting from evaporation and dissolution. This is the first report on the broad-spectrum compositional changes in oil during the first day of a spill at the sea surface. Expected outcomes under other environmental conditions are discussed, as well as comparisons to other models. PMID:25103722

  5. 43 CFR 420.3 - Adjacent lands.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 1 2014-10-01 2014-10-01 false Adjacent lands. 420.3 Section 420.3 Public Lands: Interior Regulations Relating to Public Lands BUREAU OF RECLAMATION, DEPARTMENT OF THE INTERIOR...-managing agencies on adjacent lands (both public and private)....

  6. 43 CFR 420.3 - Adjacent lands.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 1 2013-10-01 2013-10-01 false Adjacent lands. 420.3 Section 420.3 Public Lands: Interior Regulations Relating to Public Lands BUREAU OF RECLAMATION, DEPARTMENT OF THE INTERIOR...-managing agencies on adjacent lands (both public and private)....

  7. 43 CFR 420.3 - Adjacent lands.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 1 2011-10-01 2011-10-01 false Adjacent lands. 420.3 Section 420.3 Public Lands: Interior Regulations Relating to Public Lands BUREAU OF RECLAMATION, DEPARTMENT OF THE INTERIOR OFF-ROAD VEHICLE USE § 420.3 Adjacent lands. When administratively feasible, the regulation of off-road vehicle use on Reclamation lands will...

  8. 43 CFR 420.3 - Adjacent lands.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 1 2012-10-01 2011-10-01 true Adjacent lands. 420.3 Section 420.3 Public Lands: Interior Regulations Relating to Public Lands BUREAU OF RECLAMATION, DEPARTMENT OF THE INTERIOR...-managing agencies on adjacent lands (both public and private)....

  9. 43 CFR 420.3 - Adjacent lands.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Adjacent lands. 420.3 Section 420.3 Public Lands: Interior Regulations Relating to Public Lands BUREAU OF RECLAMATION, DEPARTMENT OF THE INTERIOR OFF-ROAD VEHICLE USE § 420.3 Adjacent lands. When administratively feasible, the regulation of...

  10. Fixed point Open Ocean Observatory network (FixO3): Multidisciplinary observations from the air-sea interface to the deep seafloor

    NASA Astrophysics Data System (ADS)

    Lampitt, Richard; Cristini, Luisa

    2014-05-01

    The Fixed point Open Ocean Observatory network (FixO3) seeks to integrate the 23 European open ocean fixed point observatories and to improve access to these key installations for the broader community. These will provide multidisciplinary observations in all parts of the oceans from the air-sea interface to the deep seafloor. Coordinated by the National Oceanography Centre, UK, FixO3 builds on the significant advances achieved through the previous Europe-funded FP7 programmes EuroSITES, ESONET and CARBOOCEAN. Started in September 2013 with a budget of 7 Million Euros over 4 years the project has 29 partners drawn from academia, research institutions and SME's. In addition 12 international experts from a wide range of disciplines comprise an Advisory Board. On behalf of the FixO3 Consortium, we present the programme that will be achieved through the activities of 12 Work Packages: 1. Coordination activities to integrate and harmonise the current procedures and processes. Strong links will be fostered with the wider community across academia, industry, policy and the general public through outreach, knowledge exchange and training. 2. Support actions to offer a) free access to observatory infrastructures to those who do not have such access, and b) free and open data services and products. 3. Joint research activities to innovate and enhance the current capability for multidisciplinary in situ ocean observation. Support actions include Transnational Access (TNA) to FixO3 infrastructure, meaning that European organizations can apply to free-of-charge access to the observatories for research and testing in two international calls during the project lifetime. The first call for TNA opens in summer 2014. More information can be found on FixO3 website (www.fixo3.eu/). Open ocean observation is currently a high priority for European marine and maritime activities. FixO3 will provide important data on environmental products and services to address the Marine Strategy

  11. Characteristics of total suspended matter and associated hydrocarbon concentration adjacent to the Chesapeake Bay entrance

    NASA Technical Reports Server (NTRS)

    Oertel, G. F.; Wade, T. L.

    1981-01-01

    Methodologies used to determine concentrations of hydrocarbons and associated suspended particulates at stations in and adjacent to the entrance to the Chesapeake Bay are described and the results are presented. Passive and active remote sensing data were acquired in conjunction with sea truth data collection.

  12. Nutrient fluxes in the Changjiang River estuary and adjacent waters — a modified box model approach

    NASA Astrophysics Data System (ADS)

    Wang, Xiaohong; Yu, Zhiming; Fan, Wei; Song, Xiuxian; Cao, Xihua; Yuan, Yongquan

    2015-01-01

    To solve nutrient flux and budget among waters with distinct salinity difference for water-salt-nutrient budget, a traditional method is to build a stoichiometrically linked steady state model. However, the traditional way cannot cope appropriately with those without distinct salinity difference that parallel to coastline or in a complex current system, as the results would be highly affected by box division in time and space, such as the Changjiang (Yangtze) River estuary (CRE) and adjacent waters (30.75°2-31.75°N, 122°10'-123°20'E). Therefore, we developed a hydrodynamic box model based on the traditional way and the regional oceanic modeling system model (ROMS). Using data from four cruises in 2005, horizontal, vertical and boundary nutrient fluxes were calculated in the hydrodynamic box model, in which flux fields and the major controlling factors were studied. Results show that the nutrient flux varied greatly in season and space. Water flux outweighs the nutrient concentration in horizontal flux, and upwelling flux outweighs upward diffusion flux in vertical direction (upwelling flux and upward diffusion flux regions overlap largely all the year). Vertical flux in spring and summer are much greater than that in autumn and winter. The maximum vertical flux for DIP (dissolved inorganic phosphate) occurs in summer. Additional to the fluxes of the Changjiang River discharge, coastal currents, the Taiwan Warm Current, and the upwelling, nutrient flux inflow from the southern Yellow Sea and outflow southward are found crucial to nutrient budgets of the study area. Horizontal nutrient flux is controlled by physical dilution and confined to coastal waters with a little into the open seas. The study area acts as a conveyer transferring nutrients from the Yellow Sea to the East China Sea in the whole year. In addition, vertical nutrient flux in spring and summer is a main source of DIP. Therefore, the hydrodynamic ROMS-based box model is superior to the traditional

  13. Red Sea Kinematics in Relation to the Regional Tectonics Setting

    NASA Astrophysics Data System (ADS)

    Alotaibi, T.; Furlong, K. P.

    2015-12-01

    The Red sSea extensional system started approximately 22+3 Ma. Although, there is evidence that lithospheric weakening and associated incipient extension may have taken place since 30 Ma. There is oceanic crust found in the southern part of the rift, while the northern-most part still involves continental stretching. Meantime magnetic anomalies have been observed for the southern rift, the northern rift is characterized by several deeps where magnetic anomalies have been observed as well as an indication of the transition from continental to oceanic rifting. GPS stations along the Red Sea are consistent with kinematics implied from the magnetic anomalies - an opening rate in the southern part of ~ 15 mm/yr relative to Eurasia fixed while the opening rate in the is ~8 mm/yr. This significant decreasing of the opening rate towards the north implies complexity within the Red Sea extensional system.Our purpose here is to place the Red Sea extensional kinematics within the regional tectonics context by combining constraints on the rate or style of extension within the Red Sea with tectonic activities on the adjacent continental regions. To accomplish this, we will model the extensional kinematics through time by comparing recent kinematics based on the geophysical observations with ones that based on geological observations. In terms of present-day geophysical observations, we have GPS and magnetic anomalies data, and crustal and lithospheric thickness. Geological observations primarily come from stratigraphic and structural data sets.Our overall target is to construct a tectonic model that links the timing of the change in the style and extensional rate with the tectonic activities in Afar, Gulf of Aden, Zagros, Dead Sea fault and Anatolian region.

  14. New marine data from Vietnam Margin limit the amount of extrusion of Indochina during the opening of the South China Sea

    SciTech Connect

    Huchon, P.; Le Pichon, X. ); Rangin, C. ); Thi, P.T.

    1994-07-01

    A total of 9300 km of high resolution, wide coverage multibeam (Simrad EM12) bathymetric data have been acquired offshore Vietnam during the Ponaga cruise of the R/V L'Atalante in May 1993. Gravity and magnetic measurements, 6-channel seismic data, as well as 6 dredges also have been obtained. East of central Vietnam, the margin displays northeast-southwest tectonic structures typical of a passive margin. The depth of the basement of the Nha Trang basin suggests that it could be of oceanic nature, with a 20 to 30 Ma age compatible with the age of the South China Sea oceanic crust located further east. Southeast of South Vietnam, the authors identified the western tip of the fossil axis of the South China Sea. It constitutes a propagating ridge into a highly stretched continental crust, partly intruded by volcanics. East of 110[degrees]30[prime]E, tilted blocks are symmetric with respect to the oceanic axis, whereas west of 110[degrees]30[prime]E they are mostly tilted toward the south, which suggests the occurrence a large listric normal fault associated with a large amount of extension. The normal faults bend progressively to a more northerly direction when approaching the north-south scarp that bounds the Conson basin. This geometry is compatible with a right-lateral motion, and the normal faults associated with the oceanic propagator suggest that the dextral motion is synchronous with at least the last phase of spreading in the South China Sea (23-16 Ma). Since recent offshore oil data have established that the prolongation of the Red River fault within the Gulf of Tonkin was affected by left-lateral motion from the Oligocene to the upper Miocene, the results suggest that the change from left-lateral motion in the Gulf of Tonkin to right-lateral motion along the Vietnam margin occurs because the South China Sea basin opens more rapidly than the extrusion of Indochina. Thus, the total amount of extrusion of Indochina probably does not exceed 100 or 200 km.

  15. Large-scale stress factors affecting coral reefs: open ocean sea surface temperature and surface seawater aragonite saturation over the next 400 years

    NASA Astrophysics Data System (ADS)

    Meissner, K. J.; Lippmann, T.; Sen Gupta, A.

    2012-06-01

    One-third of the world's coral reefs have disappeared over the last 30 years, and a further third is under threat today from various stress factors. The main global stress factors on coral reefs have been identified as changes in sea surface temperature (SST) and changes in surface seawater aragonite saturation (Ωarag). Here, we use a climate model of intermediate complexity, which includes an ocean general circulation model and a fully coupled carbon cycle, in conjunction with present-day observations of inter-annual SST variability to investigate three IPCC representative concentration pathways (RCP 3PD, RCP 4.5, and RCP 8.5), and their impact on the environmental stressors of coral reefs related to open ocean SST and open ocean Ωarag over the next 400 years. Our simulations show that for the RCP 4.5 and 8.5 scenarios, the threshold of 3.3 for zonal and annual mean Ωarag would be crossed in the first half of this century. By year 2030, 66-85% of the reef locations considered in this study would experience severe bleaching events at least once every 10 years. Regardless of the concentration pathway, virtually every reef considered in this study (>97%) would experience severe thermal stress by year 2050. In all our simulations, changes in surface seawater aragonite saturation lead changes in temperatures.

  16. Synchronous Japan Sea opening Miocene fore-arc volcanism in the Abukuma Mountains, NE Japan: An advancing hot asthenosphere flow versus Pacific slab melting

    NASA Astrophysics Data System (ADS)

    Yamamoto, Takahiro; Hoang, Nguyen

    2009-10-01

    During Japan Sea back-arc opening between 21 and 15 Ma, low-K tholeiitic basalts erupted in the Abukuma Mountains on the trench side of NE Japan. The basaltic rocks in this region are divided into two units by a hiatus. The lower unit consists of the 20 Ma Tenmyosan volcanic rocks, including many monogenetic basaltic volcanoes whose vents occur throughout the district. The upper unit is the Ryozen Formation that occurred at about 16 Ma. This Formation is composed of a subaerial basaltic polygenetic volcanic edifice, with a diameter of ca. 30 km. Minor amounts of andesitic and dacitic gravels occur in the distal portion of the Ryozen edifice. Low-K tholeiitic basalts of the Tenmyosan volcanic rocks and the Ryozen Formation have similar in major and trace element compositions. Their MgO content decrease from 13.2 to 3.4 wt.% with increasing incompatible element abundances and more pronounced negative Nb and Ta anomalies. Nd, Sr and Pb isotopic compositions of the Tenmyosan basalt display a range of values for SrI (0.7040-0.7050), NdI (0.5127-0.5129) and 206Pb/ 204Pb (18.2-18.5). These features suggest that the Tenmyosan monogenetic volcanism at the early stage of the Japan Sea opening was generated by intermittent ascent of minor mafic melts from heterogeneous sources. Isotopic data for the Ryozen basalt define a binary mixing trend between a depleted and enriched crust-like source, varying with SiO 2 content. These chemical changes show that, as the opening progressed, the asthenospheric source of the Ryozen basalts became more homogeneous and depleted (SrI; 0.7043, Nd; 0.5129, 206Pb/ 204Pb; 18.2), and continuous ascent of the basaltic melt was able to make a large magma chamber that was associated with significant crustal assimilation. On the other hand, hornblende dacite in the Ryozen Formation has SiO 2 contents between 66 and 74 wt.%, high Mg# from 41.7 to 54.3. The dacite also shows high Sr (417-650 ppm) and Sr/Y (35-112), and high La/Yb (12-20). Compared with

  17. Distribution of fish and macrozooplankton in ice-covered and open-water areas of the eastern Bering Sea

    NASA Astrophysics Data System (ADS)

    De Robertis, Alex; Cokelet, Edward D.

    2012-06-01

    The eastern Bering Sea shelf is a productive ecosystem with extensive commercial fisheries. Although the area is well-studied during summer months, little is known about the abundance and distribution of fish and macrozooplankton during periods of seasonal ice cover. The use of an icebreaker during the Bering Sea Ecosystem Study (BEST) provided a platform for spring acoustic surveys of fish and zooplankton in ice-covered areas for the first time. Icebreaker measurements were complemented with observations from conventional vessels during spring and summer. In spring, very little backscatter from fish (dominated by walleye pollock, Theragra chalcogramma) was observed in the ice-covered northern areas where near-bottom waters were cold (<˜0.5 °C), including areas where walleye pollock are abundant in summer. The majority of fish were observed within 40 km (and often slightly inside) the ice edge over similar seafloor depths as in summer. Together, these observations suggest that pollock, a dominant component of the ecosystem, shift their distribution to a more restricted geographic area in spring, following the ice edge southeast along the bathymetry, away from areas of cold water and extensive ice cover, then reoccupying these areas in summer. In contrast, acoustic backscatter attributed to zooplankton (likely dominated by euphausiids) was more evenly distributed, and less restricted by water temperature and ice cover. The implications of this seasonal shift in fish distribution are uncertain, but this may affect predator-prey interactions by reducing overlap of pollock with euphausiids, an important prey source, while increasing overlap of adult and juvenile pollock and potentially increasing cannibalism.

  18. Bottom up effects on bacterioplankton growth and composition during summer-autumn transition in the open NW Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    van Wambeke, F.; Ghiglione, J.-F.; Nedoma, J.; Mével, G.; Raimbault, P.

    2009-04-01

    We examined the vertical and temporal dynamics of nutrients, ectoenzymatic activities under late summer-fall transition period (September-October 2004) in NW Mediterranean Sea in relation to temporal change in factors limiting bacterial production. The depth of the mixed layer (12.8±5.3 m) was extremely stable until the onset of the destratification period after 11 October, creating a zone where diffusion of nutrient from the much deeper phosphacline (69±12 m) and nitracline (50±8 m) was probably strongly limited. However after 1st October, a shallowing of nutriclines occured, particularly marked for nitracline. Hence, the nitrate to phosphate ratio within the mixed layer, although submitted to a high short term variability, shifted the last week of the cruise from 1.1±1.2 to 4.6±3.8, and nitrate increased by a factor 2 (0.092±0.049 μM). A corresponding switch from more than one limitation (PN) to P-only limitation of bacterial production was observed during the month as detected by enrichment bioassays. Differences in the identity of the limiting nutrient in surface (5 m: N and P at the beginning, strictly P at the end of the study) versus 80 m (labile carbon) influence greatly bacterial community structure shift between these two layers. The two communities (5 and 80 m) reacted rapidly (24 h) to changes in nutrient concentrations by drastic modification of total and active population assemblages resulting in changes in activity. For bacterial production values less than 10 ng C l-1 h-1 (associated to deeper layers), aminopeptidase and lipase exhibited higher activity relative to production whereas phosphatase varied in the same proportions than BP on the range of activities tested. Our results illustrate the effect of bottom-up control on bacterial community structure and activities in the epipelagic NW Mediterranean Sea.

  19. Late Mesozoic and Cenozoic rifting and its dynamic setting in Eastern China and adjacent areas

    NASA Astrophysics Data System (ADS)

    Ren, Jianye; Tamaki, Kensaku; Li, Sitian; Junxia, Zhang

    2002-02-01

    basin margins and were deposited in a broad downwarped lacustrine depression. At the same time, within plate rifting of the Lake Baikal and Shanxi graben climaxed and spreading of the Japan Sea and South China Sea occurred. Quaternary rifting was marked by basalt eruption and accelerated subsidence in the area of Tertiary rifting. The Okinawa Trough is an active rift involving back-arc extension. Continental rifting and marginal sea opening were clearly developed in various kind of tectonic settings. Three rifting styles, intracontinental rifting within fold belt, intracontinental rifting within craton and continental marginal rifting and spreading, are distinguished on the basis of nature of the basin basement, tectonic location of rifting and relations to large strike-slip faults. Changes of convergence rates of India-Eurasia and Pacific-Eurasia may have caused NW-SE-trending extensional stress field dominating the rifting. Asthenospheric upwelling may have well assisted the rifting process. In this paper, a combination model of interactions between plates and deep process of lithosphere has been proposed to explain the rifting process in East China and adjacent areas. The research on the Late Mesozoic and Cenozoic extensional tectonics of East China and adjacent areas is important because of its utility as an indicator of the dynamic setting and deformational mechanisms involved in stretching Lithosphere. The research also benefits the exploration and development of mineral and energy resources in this area.

  20. Oxygen minimum zone of the open Arabian Sea: variability of oxygen and nitrite from daily to decadal time scales

    NASA Astrophysics Data System (ADS)

    Banse, K.; Naqvi, S. W. A.; Narvekar, P. V.; Postel, J. R.; Jayakumar, D. A.

    2013-09-01

    The oxygen minimum zone (OMZ) of the Arabian Sea is the thickest of the three oceanic OMZs, which is of global biogeochemical significance because of denitrification in the upper part leading to N2 and N2O production. The residence time of the OMZ water is believed to be less than a decade. The upper few hundred meters of this zone are nearly anoxic but non-sulfidic and still support animal (metazoan) pelagic life, possibly as a result of episodic injections of O2 by physical processes. The very low O2 values obtained with the new STOX sensor in the eastern tropical South Pacific probably also characterize the Arabian Sea OMZ, but there is no apparent reason as to why the temporal trends of the historic data should not hold. We report on discrete measurements of dissolved O2 and NO2-, besides temperature and salinity, made between 1959 and 2004 well below the tops of the sharp pycno- and oxyclines near 150, 200, 300, 400, and 500 m depth. We assemble nearly all O2 determinations (originally, 849 values, 695 in the OMZ) by the visual endpoint detection of the iodometric Winkler procedure, which in our data base yields about 0.04 mL L-1 (∼2 μM) O2 above the endpoint from modern automated titration methods. We find 632 values acceptable (480 from 150 stations in the OMZ). The data are grouped in zonally-paired boxes of 1° lat. and 2° long. centered at 8°, 10°, 12°, 15°, 18°, 20°, and 21° N along 65° E and 67° E. The latitudes of 8-12° N, outside the OMZ, are only treated in passing. The principal results are as follows: (1) an O2 climatology for the upper OMZ reveals a marked seasonality at 200 to 500 m depth with O2 levels during the northeast monsoon and spring intermonsoon season elevated over those during the southwest monsoon season (median difference, 0.08 mL L-1 [3.5 μM]). The medians of the slopes of the seasonal regressions of O2 on year for the NE and SW monsoon seasons are -0.0043 and -0.0019 mL L-1 a-1, respectively (-0.19 and -0.08 μM a

  1. Marine mammal distribution and abundance in an offshore sub-region of the northeastern Chukchi Sea during the open-water season

    NASA Astrophysics Data System (ADS)

    Aerts, Lisanne A. M.; McFarland, Alexandra E.; Watts, Bridget H.; Lomac-MacNair, Kate S.; Seiser, Pamela E.; Wisdom, Sheyna S.; Kirk, Alex V.; Schudel, Carissa A.

    2013-09-01

    This paper describes the distribution and abundance of marine mammals during the open-water season within and near three offshore oil and gas prospects in the northeastern Chukchi Sea, known as the Klondike, Burger, and Statoil study areas. We collected vessel-based marine mammal data during July-October 2008-2010 along line transects oriented in a north-south direction. Over this period, we surveyed ~18,600 km of on-transect effort in the three study areas. Sightings of cetaceans were rare. The bowhead whale was the primary cetacean species sighted and was mostly observed in October (33 of 35 animals). Pinnipeds were the most abundant marine mammals in the study area, with 980 seals and 367 walruses recorded on transect. Most seals were observed as solitary animals, while walruses were often observed in aggregations. We calculated seal and walrus densities using species-specific detection functions corrected for probability of detection. There was high interannual variability in the abundance of seals and walruses that for some species may be related to interannual differences in ice conditions. Notwithstanding this variation, the distribution data suggest that benthic-feeding bearded seals and walruses generally were more common in the Burger and Statoil study areas, which can be characterized as more benthic-dominated ecosystems. The distribution of ringed/spotted seals did not show any statistically significant differences among the study areas, although a slight preference for the Klondike and Statoil study areas was suggested. Both of these study areas are affected by Bering Sea Water from the Central Channel and have a stronger pelagic component than the Burger study area. Continued sampling of these areas will help establish whether the observed trends in marine mammal distribution and abundance are persistent.

  2. Contrasting deglacial sedimentary architecture along paleofjord systems due to distance to open-sea, and its importance for hydrocarbon generation; Late Carboniferous units of W-Gondwana, Argentina

    NASA Astrophysics Data System (ADS)

    Milana, J. P.; Kneller, B.; Dykstra, M.

    2009-04-01

    The sedimentary fill of several exhumed paleovalleys cropping out at the Precordillera of San Juan Province Argentina, is compared. All these paleovalley fills show the fairly fast passage from proglacial conditions, well defined by dropstones or by redeposited units contained striated clasts, and eventually by the presence of striated pavements, to non-glacial deep water conditions defined by the lack of proglacial indicators, but instead a much finer-grained sedimentary unit, indicating a quite rapid transgression due to the eustatic rise after deglaciation. On spite of a similar climate-eustatic evolution, the paloefjord fills are quite contrasting in their detailed sedimentary architecture and in their capacity to produce source rock lithologies. We have basically differentiated three main type-cases, and we studied a few examples of each. Each type-case correspond to a realm (internal, intermediate, and marginal) that seems to be related to the distance to the open sea, and hence the capacity to produce restricted conditions in that local segment of the flooded paleovalley. The internal realm is characterized by its closest position to the ice-cap and hence records a maximum degree of glacioisostatic load and minimum connection to open sea processes. As a result, during deglaciation, these basins become deeper and more isolated and thus, better suited for source rock production. The degree of reworking of the deposits is minimum, and preservation is maximum and it is often to record high-slope systems prograding directly onto a fjord deep basin floor. Two paloefjords were studied in detail to characterize this sedimentation mode: the Quebrada Grande and Quebrada de las Lajas paleopjords. The intermediate realm is characterized by a medial position from the ice cap and the continent margin, and it is likely to only have recorded outlet glaciers presence. The glaciostatic load was not so strong and the resulting deglacial sequences are not as thick not so muddy

  3. Mercury Redox Chemistry in Waters of the Eastern Asian Seas: From Polluted Coast to Clean Open Ocean.

    PubMed

    Ci, Zhijia; Zhang, Xiaoshan; Yin, Yongguang; Chen, Jinsheng; Wang, Shiwei

    2016-03-01

    We performed incubation experiments using seawaters from representative marine environments of the eastern Asian seas to determine the mercury (Hg) available for photoreduction (Hgr(II)), to investigate the Hg redox reaction kinetics, and to explore the effect of environmental factors and water chemistry on the Hg redox chemistry. Results show that Hgr(II) accounted for a considerable fraction of total Hg (THg) (%Hgr(II)/THg: 24.90 ± 10.55%, n = 27) and positively correlated with THg. Filtration decreased the Hgr(II) pool of waters with high suspended particulate matter (SPM). The positive linear relationships were found between pseudo-first order rate constants of gross Hg(II) photoreduction (kr) and gross Hg(0) photo-oxidation (ko) with photosynthetically active radiation (PAR). Under the condition of PAR of 1 m mol m(-2) s(-1), the kr were significantly (p < 0.05) lower than ko (kr/ko: 0.86 ± 0.22). The Hg(0) dark oxidation were significantly higher than the Hg(II) dark reduction. The Hg(II) dark reduction was positively correlated to THg, and the anaerobic condition favored the Hg(II) dark reduction. Filtration significantly influenced the Hg photoredox chemistry of waters with high SPM. UVB radiation was important for both Hg(II) photoreduction and Hg(0) photo-oxidation, and the role of other wavebands in photoinduced transformations of Hg varied with the water chemistry. PMID:26863412

  4. Genetic and ecophysiological traits of Synechococcus strains isolated from coastal and open ocean waters of the Arabian Sea.

    PubMed

    Bemal, Suchandan; Anil, Arga Chandrashekar

    2016-11-01

    The picocyanobacterium Synechococcus is a prominent primary producer in the marine environment. The marine Synechococcus strains are clustered into different clades representing ecologically distinct genotypes. In this study, we compared phylogeny, photophysiology and cell cycles of four novel phycoerythrin-containing Synechococcus strains (clade II of subcluster 5.1) isolated from different depths of the water column (surface and subsurface waters) in coastal and offshore regions of the eastern Arabian Sea. The surface water strains possessed a lesser number of thylakoid layers and had a higher zeaxanthin to chlorophyll a ratio than subsurface strains indicating possible influence of light intensity available at their niche. The DNA distribution pattern of the four strains was bimodal in optimal cellular physiology conditions with cell division restricted to the light period and synchronized with the light-dark cycle. The presence of phycourobilin or phycoerythrobilin and the ratio between these two chromophores in all four strains varied according to available spectral wavelength in situ This study indicates that the timing of cell division is conserved within these genotypically identical Synechococcus strains, despite their having different chromophore ratios. We conclude that the timing of cell division of the Synechococcus strains has a genetic basis rather than being determined by phenotypic characters, such as chromophore content and ratio. PMID:27495242

  5. New Evidence for opening of the Black Sea; U-Pb analysis of detrital zircons and paleocurrent measurements of the Early Cretaceous turbidites

    NASA Astrophysics Data System (ADS)

    Akdoğan, Remziye; Okay, Aral I.; Sunal, Gürsel; Tari, Gabor; Kylander-Clark, Andrew R. C.

    2015-04-01

    have a late Neoproterozoic basement, whereas the East European Platform (EEP) has a Paleoproterozoic-Archean basement. The zircon and the paleocurrent data indicate that the eastern and central part of the Early Cretaceous turbidite basin was mainly fed by EEP, whereas local sources were dominant in the western part of the basin and especially fed from a crystalline basement of the Istanbul zone. This in turn indicates that the Black Sea did not form a major barrier between the Pontides and the EEP and was probably not open during the Early Cretaceous. Keywords: Central Pontides, Early Cretaceous, Paleocurrent, Provenance, U-Pb Detrital zircon.

  6. On the time-course of adjacent and non-adjacent transposed-letter priming

    PubMed Central

    Ktori, Maria; Kingma, Brechtsje; Hannagan, Thomas; Holcomb, Phillip J.; Grainger, Jonathan

    2014-01-01

    We compared effects of adjacent (e.g., atricle-ARTICLE) and non-adjacent (e.g., actirle-ARTICLE) transposed-letter (TL) primes in an ERP study using the sandwich priming technique. TL priming was measured relative to the standard double-substitution condition. We found significantly stronger priming effects for adjacent transpositions than non-adjacent transpositions (with 2 intervening letters) in behavioral responses (lexical decision latencies), and the adjacent priming effects emerged earlier in the ERP signal, at around 200 ms post-target onset. Non-adjacent priming effects emerged about 50 ms later and were short-lived, being significant only in the 250-300 ms time-window. Adjacent transpositions on the other hand continued to produce priming in the N400 time-window (300-500 ms post-target onset). This qualitatively different pattern of priming effects for adjacent and non-adjacent transpositions is discussed in the light of different accounts of letter transposition effects, and the utility of drawing a distinction between positional flexibility and positional noise. PMID:25364497

  7. Oxygen minimum zone of the open Arabian Sea: variability of oxygen and nitrite from daily to decadal timescales

    NASA Astrophysics Data System (ADS)

    Banse, K.; Naqvi, S. W. A.; Narvekar, P. V.; Postel, J. R.; Jayakumar, D. A.

    2014-04-01

    The oxygen minimum zone (OMZ) of the Arabian Sea is the thickest of the three oceanic OMZ. It is of global biogeochemical significance because of denitrification in the upper part leading to N2 and N2O production. The residence time of OMZ water is believed to be less than a decade. The upper few hundred meters of this zone are nearly anoxic but non-sulfidic and still support animal (metazoan) pelagic life, possibly as a result of episodic injections of O2 by physical processes. We report on discrete measurements of dissolved O2 and NO2-, temperature and salinity made between 1959 and 2004 well below the tops of the sharp pycnocline and oxycline near 150, 200, 300, 400, and 500 m depth. We assemble nearly all O2 determinations (originally there were 849 values, 695 of which came from the OMZ) by the visual endpoint detection of the iodometric Winkler procedure, which in our data base yields about 0.04 mL L-1 (~ 2 μM) O2 above the endpoint from modern automated titration methods. We acknowledge that much lower (nanomolar) O2 values have been measured recently with the STOX (Switchable Trace amount OXygen) sensor in the eastern tropical South Pacific, and that similar conditions may also prevail in the Arabian Sea OMZ. In spite of the error in O2 measurements at vanishingly low levels, we argue that the temporal trends of the historic data should still hold. We find 632 values acceptable (480 from 150 stations in the OMZ). The data are grouped in zonally paired boxes of 1° lat. and 2° long. centered at 8, 10, 12, 15, 18, 20, and 21° N along 65 and 67° E. The latitudes of 8-12° N, outside the OMZ, are treated in passing. The principal results are as follows: (1) an O2 climatology for the upper OMZ reveals a marked seasonality at 200 to 500 m depth with O2 levels during the northeast monsoon and spring intermonsoon seasons elevated over those during the southwest monsoon season (median difference, 0.08 mL L-1 [~ 3.5 μM]). The medians of the slopes of the

  8. Modeling of Nonlinear Hydrodynamics of the Coastal Areas of the Black Sea by the Chain of the Proprietary and Open Source Models

    NASA Astrophysics Data System (ADS)

    Kantardgi, Igor; Zheleznyak, Mark; Demchenko, Raisa; Dykyi, Pavlo; Kivva, Sergei; Kolomiets, Pavlo; Sorokin, Maxim

    2014-05-01

    The nearshore hydrodynamic fields are produced by the nonlinear interactions of the shoaling waves of different time scales and currents. To simulate the wind wave and swells propagated to the coasts, wave generated near shore currents, nonlinear-dispersive wave transformation and wave diffraction in interaction with coastal and port structure, sediment transport and coastal erosion the chains of the models should be used. The objective of this presentation is to provide an overview of the results of the application of the model chains for the assessment of the wave impacts on new construction designed at the Black Sea coasts and the impacts of these constructions on the coastal erosion/ accretion processes to demonstrate needs for further development of the nonlinear models for the coastal engineering applications. The open source models Wave Watch III and SWAN has been used to simulate wave statistics of the dedicated areas of the Black Sea in high resolution to calculated the statistical parameters of the extreme wave approaching coastal zone construction in accordance with coastal engineering standards. As the main tool for the costal hydrodynamic simulations the modeling system COASTOX-MORPHO has been used, that includes the following models. HWAVE -code based on hyperbolic version of mild slope equations., HWAVE-S - spectral version of HWAVE., BOUSS-FNL - fully nonlinear system of Boussinesq equations for simulation wave nonlinear -dispersive wave transformation in coastal areas. COASTOX-CUR - the code provided the numerical solution of the Nonlinear Shallow Water Equations (NLSWE) by finite-volume methods on the unstructured grid describing the long wave transformation in the coastal zone with the efficient drying -wetting algorithms to simulate the inundation of the coastal areas including tsunami wave runup. Coastox -Cur equations with the radiation stress term calculated via near shore wave fields simulate the wave generated nearhore currents. COASTOX

  9. SOLIDS TRANSPORT BETWEEN ADJACENT CAFB FLUIDIZED BEDS

    EPA Science Inventory

    The report gives results of an experimental investigation of a pulsed, dense-phase pneumatic transport system for controlled circulation between adjacent fluidized beds. A model was developed to predict performance. The program provides technical support for EPA's program to demo...

  10. Border separation for adjacent orthogonal fields

    SciTech Connect

    Werner, B.L.; Khan, F.M.; Sharma, S.C.; Lee, C.K.; Kim, T.H. )

    1991-06-01

    Field border separations for adjacent orthogonal fields can be calculated geometrically, given the validity of some important assumptions such as beam alignment and field uniformity. Thermoluminescent dosimetry (TLD) measurements were used to investigate dose uniformity across field junctions as a function of field separation and, in particular, to review the CCSG recommendation for the treatment of medulloblastoma with separate head and spine fields.

  11. Global sea level rise

    SciTech Connect

    Douglas, B.C. )

    1991-04-15

    Published values for the long-term, global mean sea level rise determined from tide gauge records exhibit considerable scatter, from about 1 mm to 3 mm/yr. This disparity is not attributable to instrument error; long-term trends computed at adjacent sites often agree to within a few tenths of a millimeter per year. Instead, the differing estimates of global sea level rise appear to be in large part due to authors' using data from gauges located at convergent tectonic plate boundaries, where changes of land elevation give fictitious sea level trends. In addition, virtually all gauges undergo subsidence or uplift due to postglacial rebound (PGR) from the last deglaciation at a rate comparable to or greater than the secular rise of sea level. Modeling PGR by the ICE-3G model of Tushingham and Peltier (1991) and avoiding tide gauge records in areas of converging tectonic plates produces a highly consistent set of long sea level records. The value for mean sea level rise obtained from a global set of 21 such stations in nine oceanic regions with an average record length of 76 years during the period 1880-1980 is 1.8 mm/yr {plus minus} 0.1. This result provides confidence that carefully selected long tide gauge records measure the same underlying trend of sea level and that many old tide gauge records are of very high quality.

  12. Flow and transport within a coastal aquifer adjacent to a stratified water body

    NASA Astrophysics Data System (ADS)

    Oz, Imri; Yechieli, Yoseph; Eyal, Shalev; Gavrieli, Ittai; Gvirtzman, Haim

    2016-04-01

    The existence of a freshwater-saltwater interface and the circulation flow of saltwater beneath the interface is a well-known phenomenon found at coastal aquifers. This flow is a natural phenomenon that occurs due to density differences between fresh groundwater and the saltwater body. The goals of this research are to use analytical, numerical, and physical models in order to examine the configuration of the freshwater-saltwater interface and the density-driven flow patterns within a coastal aquifer adjacent to long-term stratified saltwater bodies (e.g. meromictic lake). Such hydrological systems are unique, as they consist of three different water types: the regional fresh groundwater, and low and high salinity brines forming the upper and lower water layers of the stratified water body, respectively. This research also aims to examine the influence of such stratification on hydrogeological processes within the coastal aquifer. The coastal aquifer adjacent to the Dead Sea, under its possible future meromictic conditions, serves as an ideal example to examine these processes. The results show that adjacent to a stratified saltwater body three interfaces between three different water bodies are formed, and that a complex flow system, controlled by the density differences, is created, where three circulation cells are developed. These results are significantly different from the classic circulation cell that is found adjacent to non-stratified water bodies (lakes or oceans). In order to obtain a more generalized insight into the groundwater behavior adjacent to a stratified water body, we used the numerical model to perform sensitivity analysis. The hydrological system was found be sensitive to three dimensionless parameters: dimensionless density (i.e. the relative density of the three water bodies'); dimensionless thickness (i.e. the ratio between the relative thickness of the upper layer and the whole thickness of the lake); and dimensionless flux. The results

  13. Adjacent Segment Pathology after Lumbar Spinal Fusion.

    PubMed

    Lee, Jae Chul; Choi, Sung-Woo

    2015-10-01

    One of the major clinical issues encountered after lumbar spinal fusion is the development of adjacent segment pathology (ASP) caused by increased mechanical stress at adjacent segments, and resulting in various radiographic changes and clinical symptoms. This condition may require surgical intervention. The incidence of ASP varies with both the definition and methodology adopted in individual studies; various risk factors for this condition have been identified, although a significant controversy still exists regarding their significance. Motion-preserving devices have been developed, and some studies have shown their efficacy of preventing ASP. Surgeons should be aware of the risk factors of ASP when planning a surgery, and accordingly counsel their patients preoperatively. PMID:26435804

  14. Adjacent Segment Pathology after Anterior Cervical Fusion

    PubMed Central

    Chung, Jae Yoon; Park, Jong-Beom; Seo, Hyoung-Yeon

    2016-01-01

    Anterior cervical fusion has become a standard of care for numerous pathologic conditions of the cervical spine. However, subsequent development of clinically significant disc disease at levels adjacent to fused discs is a serious long-term complication of this procedure. As more patients live longer after surgery, it is foreseeable that adjacent segment pathology (ASP) will develop in increasing numbers of patients. Also, ASP has been studied more intensively with the recent popularity of motion preservation technologies like total disc arthroplasty. The true nature and scope of ASP remains poorly understood. The etiology of ASP is most likely multifactorial. Various factors including altered biomechanical stresses, surgical disruption of soft tissue and the natural history of cervical disc disease contribute to the development of ASP. General factors associated with disc degeneration including gender, age, smoking and sports may play a role in the development of ASP. Postoperative sagittal alignment and type of surgery are also considered potential causes of ASP. Therefore, a spine surgeon must be particularly careful to avoid unnecessary disruption of the musculoligamentous structures, reduced risk of direct injury to the disc during dissection and maintain a safe margin between the plate edge and adjacent vertebrae during anterior cervical fusion. PMID:27340541

  15. Adjacent Segment Pathology after Anterior Cervical Fusion.

    PubMed

    Chung, Jae Yoon; Park, Jong-Beom; Seo, Hyoung-Yeon; Kim, Sung Kyu

    2016-06-01

    Anterior cervical fusion has become a standard of care for numerous pathologic conditions of the cervical spine. However, subsequent development of clinically significant disc disease at levels adjacent to fused discs is a serious long-term complication of this procedure. As more patients live longer after surgery, it is foreseeable that adjacent segment pathology (ASP) will develop in increasing numbers of patients. Also, ASP has been studied more intensively with the recent popularity of motion preservation technologies like total disc arthroplasty. The true nature and scope of ASP remains poorly understood. The etiology of ASP is most likely multifactorial. Various factors including altered biomechanical stresses, surgical disruption of soft tissue and the natural history of cervical disc disease contribute to the development of ASP. General factors associated with disc degeneration including gender, age, smoking and sports may play a role in the development of ASP. Postoperative sagittal alignment and type of surgery are also considered potential causes of ASP. Therefore, a spine surgeon must be particularly careful to avoid unnecessary disruption of the musculoligamentous structures, reduced risk of direct injury to the disc during dissection and maintain a safe margin between the plate edge and adjacent vertebrae during anterior cervical fusion. PMID:27340541

  16. Can the South China Sea tell us anything about Canada Basin?

    NASA Astrophysics Data System (ADS)

    Stephenson, Randell; Li, Lu

    2016-04-01

    The Canada Basin (a sub-basin within the Amerasia Basin) and the South China Sea both preserve oceanic spreading centres and adjacent passive continental margins characterised by broad continent-ocean transition zones with hyper-extended continental crust. There are indications that hyper-extension in the South China Sea occurred mainly as a result of flow within a weak lower crustal layer and that it occurred both before and after plate break-up and the onset of ocean lithosphere formation at the sea-floor spreading axis. Available geophysical data from Canada Basin permit similar inferences. Both basins are about the same size and the oceanic segment in both is about the same size. Seafloor spreading in the South China Sea took place in the Cenozoic whereas in Canada Basin it is widely believed to have occurred during the Cretaceous. Widespread magmatism expressed as the High Arctic Large Igneous Province (HALIP) may or may not have played an intrinsic, linked, role in Canada Basin formation. No similar LIP is associated with the South China Sea although one mechanism proposed to have driven its formation is ascribed to mantle plume activity in its northernmost part. More conventionally the mechanism of opening of the South China Sea is considered to be "passive" rather than "active", related to plate reconfigurations in the southeast Asia region linked or not linked to the nearby collision of India and Eurasia and/or subduction of a "proto-South China Sea". The driving mechanism for opening of Canada Basin is poorly discussed in the literature but is generally ascribed to paleo-tectonic plate reconfigurations and subduction in the northern Pacific (Eurasia-North America plates) region in the Mesozoic. Can the South China Sea tell us anything about Canada Basin in terms of the pre-existing lithosphere of each and the geodynamic processes leading to its hyper-extension and eventual break-up?

  17. A Shift to Melted Sea Ice From Runoff as the Major Component of Chukchi Shelf Open Water Freshwater Fractions, 1993-2013

    NASA Astrophysics Data System (ADS)

    Cooper, L. W.; Frey, K. E.; Logvinova, C. L.; Biasatti, D. M.; Grebmeier, J. M.

    2014-12-01

    The freshwater fraction of water that is derived from melted sea ice has increased significantly on the Chukchi shelf relative to runoff within the past decade, based upon analysis of salinity and δ18O mixing lines from a number of research cruises from 1993-2013. The shift to summertime dominance of melted sea ice (freshwater end-member δ18O >-10 per mil) relative to runoff occurred within the past ten years with a transition primarily observed from runoff dominance to sea ice melt after 2004. This shift is localized to the Chukchi shelf and does not reflect large amounts of melted sea ice flowing north through Bering Strait, which still largely transports a freshwater component with runoff origins (freshwater end-member δ18O ~-20 per mil). These observations have implications for understanding high latitude shelf biogeochemical cycling as melted sea ice carries much lower fractions of dissolved organic carbon (DOC) than runoff, allowing for greater light penetration, including through melt ponds in sea ice, and potential changes in productivity. Lower alkalinity and buffering capacity in melted sea ice compared to runoff will also increase the vulnerability of shelf organisms to water column acidification. Melted sea ice, with low DOC relative to runoff can dominate the freshwater budget in Chukchi shelf waters even under apparently continuous ice coverage. The higher transmission of light through melted sea ice with low DOC may be in part responsible for recent reported under-ice blooms on the Chukchi shelf. Since these blooms occur in waters with the freshwater budget dominated by melted sea ice, they can reasonably interpreted as being part of a continuum with other ice melt-associated blooms and not independent of sea ice retreat and dissolution.

  18. Weekly Cycle of Lightning and Associated Patterns of Rainfall, Cloud, and Aerosols over Korea and Adjacent Oceans during Boreal Summer

    NASA Technical Reports Server (NTRS)

    Kim, Ji-In; Kim, Kyu-Myong

    2011-01-01

    In this study, we analyze the weekly cycle of lightning over Korea and adjacent oceans and associated variations of aerosols, clouds, precipitation, and atmospheric circulations, using aerosol optical depth (AOD) from the NASA Moderate resolution Imaging Spectroradiometer (MODIS) and Multi-angle Imaging SpectroRadiometer (MISR), cloud properties from MODIS, precipitation and storm height from Tropical Rainfall Measuring Mission (TRMM) satellite, and lightning data from the Korean Lightning Detection Network (KLDN) during 9-year from 2002 to 2010. Lightning data was divided into three approximately equal areas, land area of Korea, and two adjacent oceans, Yellow Sea and South Sea. Preliminary results show that the number of lightning increases during the middle of the week over Yellow Sea. AOD data also shows moderately significant midweek increase at about the same time as lightning peaks. These results are consistent with the recent studies showing the invigoration of storms with more ice hydrometeors by aerosols, and subsequently wash out of aerosols by rainfall. Frequency of lightning strokes tend to peak at weekend in land area and over South Sea, indicating local weekly anomalous circulation between land and adjacent ocean. On the other hand, lightning frequency over Yellow Sea appears to have very strong weekly cycle with midweek peak on around Wednesday. It is speculated that the midweek peak of lightning over Yellow Sea was related with aerosol transport from adjacent land area. AOD data also suggests midweek peak over Yellow Sea, however, the weekly cycle of AOD was not statistically significant. Changes in weekly cycle of lightning from pre-monsoon to monsoon season, as well as associated clouds and circulation patterns are also discussed.

  19. Reconstructing genome mixtures from partial adjacencies.

    PubMed

    Mahmoody, Ahmad; Kahn, Crystal L; Raphael, Benjamin J

    2012-01-01

    Many cancer genome sequencing efforts are underway with the goal of identifying the somatic mutations that drive cancer progression. A major difficulty in these studies is that tumors are typically heterogeneous, with individual cells in a tumor having different complements of somatic mutations. However, nearly all DNA sequencing technologies sequence DNA from multiple cells, thus resulting in measurement of mutations from a mixture of genomes. Genome rearrangements are a major class of somatic mutations in many tumors, and the novel adjacencies (i.e. breakpoints) resulting from these rearrangements are readily detected from DNA sequencing reads. However, the assignment of each rearrangement, or adjacency, to an individual cancer genome in the mixture is not known. Moreover, the quantity of DNA sequence reads may be insufficient to measure all rearrangements in all genomes in the tumor. Motivated by this application, we formulate the k-minimum completion problem (k-MCP). In this problem, we aim to reconstruct k genomes derived from a single reference genome, given partial information about the adjacencies present in the mixture of these genomes. We show that the 1-MCP is solvable in linear time in the cases where: (i) the measured, incomplete genome has a single circular or linear chromosome; (ii) there are no restrictions on the chromosomal content of the measured, incomplete genome. We also show that the k-MCP problem, for k ≥ 3 in general, and the 2-MCP problem with the double-cut-and-join (DCJ) distance are NP-complete, when there are no restriction on the chromosomal structure of the measured, incomplete genome. These results lay the foundation for future algorithmic studies of the k-MCP and the application of these algorithms to real cancer sequencing data. PMID:23282028

  20. Rayleigh wave tomography of China and adjacent regions

    NASA Astrophysics Data System (ADS)

    Huang, Zhongxian; Su, Wei; Peng, Yanju; Zheng, Yuejun; Li, Hongyi

    2003-02-01

    This paper presents a tomographic study on the S wave velocity structure of China and adjacent regions. Group velocity dispersions of fundamental Rayleigh waves along more than 4000 paths were determined with frequency-time analysis. The study region was divided into a 1° × 1° grid, and velocities in between grid nodes were calculated by bilinear interpolation. The Occam's inversion scheme was adopted to invert for group velocity distributions. This method is robust and allows us to use a fine grid in model parameterization and thus helps to restore a more realistic velocity pattern. Checkerboard tests were carried out, and the lateral resolution was estimated to be 4°-6° in China and its eastern continental shelves. The resulting group velocity maps from 10 to 184 s showed good correlation with known geological and tectonic features. The pure path dispersion curves at each node were inverted for shear wave velocity structures. The three-dimensional velocity model indicates thick lithospheres in the Yangtze and Tarim platforms and hot upper mantles in Baikal and western Mongolia, coastal area and continental shelves of eastern China, and Indochina and South China Sea regions. The Tibetan Plateau has a very thick crust with a low-velocity zone in its middle. Beneath the crust a north dipping high-velocity zone, mimicking a subducting plate, reaches to 200 km in depth and reaches to the Kunlun Mountains northward. In northern Tibet a low-velocity zone immediately below the Moho extends eastward then turns southward along the eastern edge of the plateau until it connects to the vast low-velocity area in Indochina and the South China Sea.

  1. CO2, CH4, and N2O in the Open Ocean, Sea-ice Zone, and Polynya of the Southern Ocean Observed during Austral Summer Season from 2009 to 2013

    NASA Astrophysics Data System (ADS)

    Rhee, T. S.; Park, K.; Hahm, D.; Jeon, H.; Park, K.; Kwon, Y.; Shin, H.; Lee, S.; Lee, K. E.

    2013-12-01

    Korean ice-breaking research vessel Araon has been at sea since 2010 carrying out a variety of research activities. During these periods we measured CO2, CH4, and N2O at sea below and above the sea surface to estimate sink or source strengths of the ocean in the characteristic provinces at high latitude. The ocean plays a wide range of role in the budget of these gases in the atmosphere: as a sink for CO2 and a source for CH4 and N2O. High latitude of the Southern Ocean is particularly important as the change in the cryosphere can impact the ecological and physical settings that govern the content and flux of these dissolved gases in seawater. We have visited the Amundsen Sea during the austral summer in 2010/2011 and 2012, and the Ross Sea in 2013 in order to investigate the impact of the change in the cryospheric environments. In addition we had opportunity to survey the Pacific sector of the Southern Ocean in 2009 onboard R/V Polarstern. In the open ocean, CO2 in the seawater was mostly undersaturated, CH4 was in equilibrium or slightly undersaturated, and N2O was supersaturated with respect to that in the marine boundary layer. These features were not observed in the sea-ice zone; CO2 in the seawater was slightly supersaturated in 2011, but not in 2012 and 2013, while dissolved CH4 was undersaturated and N2O was supersaturated for three years. In the polynya of the Amundsen Sea and the Ross Sea, CO2 and CH4 were undersaturated in the seawater while N2O was supersaturated with respect to that in the atmosphere. Based on these 4-year observations during austral summer season, high latitude of the southern ocean contributes as a strong sink for atmospheric CO2 whilst as a strong source for N2O. In the case of CH4, the Southern Ocean acted as a sink of the atmospheric CH4, which differs from the role of the ocean in the global scale.

  2. The Current Tectonics of the Yukon and Adjacent Area

    NASA Astrophysics Data System (ADS)

    Hyndman, R. D.; Leonard, L. J.

    2014-12-01

    The current tectonics across the Yukon and adjacent areas of western Northwest Territories (NWT) and northern British Columbia appear to be driven primarily by the Yakutat Terrane collision, an "indenter" in the corner of the Gulf of Alaska. GPS data show 1-10 mm/yr northward and eastward, decreasing inland. The rates from earthquake statistics are similar although there are important discrepancies. The eastern Cordillera earthquake mechanisms are mainly thrust in the Mackenzie Mountains of southwestern NWT where the Cordillera upper crust is overthrusting the craton. To the north, the mechanisms are mainly strike-slip in the Richardson Mountains that appear to lie along the edge of the craton. The deformation appears to be limited to the hot and weak Cordillera with the strong craton providing an irregular eastern boundary. For example, there is an eastward bow in the craton edge and the deformation in the Mackenzie Mountains. On the Beaufort Sea margin in the region of the Mackenzie Delta there appears to be a type of "subduction zone" with the continent very slowly overthrusting the oceanic plate, a process that has continued since at least the Cretaceous. A northward moving continental margin block is bounded by left lateral faulting in the west (Canning Displacement Zone of eastern Alaska) and right lateral faulting in the east (Richardson Mountains in eastern Yukon). There is almost no seismicity on this thrust belt but as for some other subduction zones such as Cascadia there is the potential for very infrequent great earthquakes.

  3. Exchange coupling between laterally adjacent nanomagnets.

    PubMed

    Dey, H; Csaba, G; Bernstein, G H; Porod, W

    2016-09-30

    We experimentally demonstrate exchange-coupling between laterally adjacent nanomagnets. Our results show that two neighboring nanomagnets that are each antiferromagnetically exchange-coupled to a common ferromagnetic bottom layer can be brought into strong ferromagnetic interaction. Simulations show that interlayer exchange coupling effectively promotes ferromagnetic alignment between the two nanomagnets, as opposed to antiferromagnetic alignment due to dipole-coupling. In order to experimentally demonstrate the proposed scheme, we fabricated arrays of pairs of elongated, single-domain nanomagnets. Magnetic force microscopy measurements show that most of the pairs are ferromagnetically ordered. The results are in agreement with micromagnetic simulations. The presented scheme can achieve coupling strengths that are significantly stronger than dipole coupling, potentially enabling far-reaching applications in Nanomagnet Logic, spin-wave devices and three-dimensional storage and computing. PMID:27535227

  4. Boundary Layers of Air Adjacent to Cylinders

    PubMed Central

    Nobel, Park S.

    1974-01-01

    Using existing heat transfer data, a relatively simple expression was developed for estimating the effective thickness of the boundary layer of air surrounding cylinders. For wind velocities from 10 to 1000 cm/second, the calculated boundary-layer thickness agreed with that determined for water vapor diffusion from a moistened cylindrical surface 2 cm in diameter. It correctly predicted the resistance for water vapor movement across the boundary layers adjacent to the (cylindrical) inflorescence stems of Xanthorrhoea australis R. Br. and Scirpus validus Vahl and the leaves of Allium cepa L. The boundary-layer thickness decreased as the turbulence intensity increased. For a turbulence intensity representative of field conditions (0.5) and for νwindd between 200 and 30,000 cm2/second (where νwind is the mean wind velocity and d is the cylinder diameter), the effective boundary-layer thickness in centimeters was equal to [Formula: see text]. PMID:16658855

  5. Spatial patterns in the length of the sea ice season in the Southern Ocean, 1979-1986

    NASA Technical Reports Server (NTRS)

    Parkinson, Claire L.

    1994-01-01

    The length of the sea ice season summarizes in one number the ice coverage conditions for an individual location for an entire year. It becomes a particularly valuable variable when mapped spatially over a large area and examined for regional and interannual differences, as is done here for the Southern Ocean over the years 1979-1986, using the satellite passive microwave data of the Nimbus 7 scanning multichannel microwave radiometer. Three prominent geographic anomalies in ice season lengths occur consistently in each year of the data set, countering the general tendency toward shorter ice seasons from south to north: (1) in the Weddell Sea the tendency is toward shorter ice seasons from southwest to northeast, reflective of the cyclonic ice/atmosphere/ocean circulations in the Weddell Sea region. (2) Directly north of the Ross Ice Shelf anomalously short ice seasons occur, lasting only 245-270 days, in contrast to the perennial ice coverage at comparable latitudes in the southern Bellingshausen and Amundsen Seas and in the western Weddell Sea. The short ice season off the Ross Ice Shelf reflects the consistently early opening of the ice cover each spring, under the influence of upwelling along the continental slope and shelf and atmospheric forcing from winds blowing off the Antarctic continent. (3) In the southern Amundsen Sea, anomalously short ice seasons occur adjacent to the coast, owing to the frequent existence of coastal polynyas off the many small ice shelves bordering the sea. Least squares trends in the ice season lengths over the 1979-1986 period are highly coherent spatially, with overall trends toward shorter ice seasons in the northern Weddell and Bellingshausen seas and toward longer ice seasons in the Ross Sea, around much of East Antarctica, and in a portion of the south central Weddell Sea.

  6. 30 CFR 56.9103 - Clearance on adjacent tracks.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Clearance on adjacent tracks. 56.9103 Section..., Hauling, and Dumping Traffic Safety § 56.9103 Clearance on adjacent tracks. Railcars shall not be left on side tracks unless clearance is provided for traffic on adjacent tracks....

  7. 30 CFR 57.9103 - Clearance on adjacent tracks.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Clearance on adjacent tracks. 57.9103 Section..., Hauling, and Dumping Traffic Safety § 57.9103 Clearance on adjacent tracks. Railcars shall not be left on side tracks unless clearance is provided for traffic on adjacent tracks....

  8. 30 CFR 56.9103 - Clearance on adjacent tracks.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Clearance on adjacent tracks. 56.9103 Section..., Hauling, and Dumping Traffic Safety § 56.9103 Clearance on adjacent tracks. Railcars shall not be left on side tracks unless clearance is provided for traffic on adjacent tracks....

  9. 30 CFR 57.9103 - Clearance on adjacent tracks.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Clearance on adjacent tracks. 57.9103 Section..., Hauling, and Dumping Traffic Safety § 57.9103 Clearance on adjacent tracks. Railcars shall not be left on side tracks unless clearance is provided for traffic on adjacent tracks....

  10. 33 CFR 80.1395 - Puget Sound and adjacent waters.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Puget Sound and adjacent waters... INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Thirteenth District § 80.1395 Puget Sound and adjacent waters. The 72 COLREGS shall apply on all waters of Puget Sound and adjacent waters, including Lake...

  11. 33 CFR 80.1395 - Puget Sound and adjacent waters.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Puget Sound and adjacent waters... INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Thirteenth District § 80.1395 Puget Sound and adjacent waters. The 72 COLREGS shall apply on all waters of Puget Sound and adjacent waters, including Lake...

  12. 33 CFR 80.1395 - Puget Sound and adjacent waters.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Puget Sound and adjacent waters... INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Thirteenth District § 80.1395 Puget Sound and adjacent waters. The 72 COLREGS shall apply on all waters of Puget Sound and adjacent waters, including Lake...

  13. 33 CFR 80.1395 - Puget Sound and adjacent waters.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Puget Sound and adjacent waters... INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Thirteenth District § 80.1395 Puget Sound and adjacent waters. The 72 COLREGS shall apply on all waters of Puget Sound and adjacent waters, including Lake...

  14. 33 CFR 80.1395 - Puget Sound and adjacent waters.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Puget Sound and adjacent waters... INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Thirteenth District § 80.1395 Puget Sound and adjacent waters. The 72 COLREGS shall apply on all waters of Puget Sound and adjacent waters, including Lake...

  15. Seafloor Control on Sea Ice

    NASA Technical Reports Server (NTRS)

    Nghiem, S. V.; Clemente-Colon, P.; Rigor, I. G.; Hall, D. K.; Neumann, G.

    2011-01-01

    The seafloor has a profound role in Arctic sea ice formation and seasonal evolution. Ocean bathymetry controls the distribution and mixing of warm and cold waters, which may originate from different sources, thereby dictating the pattern of sea ice on the ocean surface. Sea ice dynamics, forced by surface winds, are also guided by seafloor features in preferential directions. Here, satellite mapping of sea ice together with buoy measurements are used to reveal the bathymetric control on sea ice growth and dynamics. Bathymetric effects on sea ice formation are clearly observed in the conformation between sea ice patterns and bathymetric characteristics in the peripheral seas. Beyond local features, bathymetric control appears over extensive ice-prone regions across the Arctic Ocean. The large-scale conformation between bathymetry and patterns of different synoptic sea ice classes, including seasonal and perennial sea ice, is identified. An implication of the bathymetric influence is that the maximum extent of the total sea ice cover is relatively stable, as observed by scatterometer data in the decade of the 2000s, while the minimum ice extent has decreased drastically. Because of the geologic control, the sea ice cover can expand only as far as it reaches the seashore, the continental shelf break, or other pronounced bathymetric features in the peripheral seas. Since the seafloor does not change significantly for decades or centuries, sea ice patterns can be recurrent around certain bathymetric features, which, once identified, may help improve short-term forecast and seasonal outlook of the sea ice cover. Moreover, the seafloor can indirectly influence cloud cover by its control on sea ice distribution, which differentially modulates the latent heat flux through ice covered and open water areas.

  16. Record Sea Ice Minimum

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Arctic sea ice reached a record low in September 2007, below the previous record set in 2005 and substantially below the long-term average. This image shows the Arctic as observed by the Advanced Microwave Scanning Radiometer for EOS (AMSR-E) aboard NASA's Aqua satellite on September 16, 2007. In this image, blue indicates open water, white indicates high sea ice concentration, and turquoise indicates loosely packed sea ice. The black circle at the North Pole results from an absence of data as the satellite does not make observations that far north. Three contour lines appear on this image. The red line is the 2007 minimum, as of September 15, about the same time the record low was reached, and it almost exactly fits the sea ice observed by AMSR-E. The green line indicates the 2005 minimum, the previous record low. The yellow line indicates the median minimum from 1979 to 2000.

  17. Seasonal variation in sea turtle density and abundance in the southeast Florida current and surrounding waters

    SciTech Connect

    Bovery, Caitlin M.; Wyneken, Jeanette

    2015-12-30

    Assessment and management of sea turtle populations is often limited by a lack of available data pertaining to at-sea distributions at appropriate spatial and temporal resolutions. Assessing the spatial and temporal distributions of marine turtles in an open system poses both observational and analytical challenges due to the turtles’ highly migratory nature. Surface counts of marine turtles in waters along the southern part of Florida’s east coast were made in and adjacent to the southeast portion of the Florida Current using standard aerial surveys during 2011 and 2012 to assess their seasonal presence. This area is of particular concern for sea turtles as interest increases in offshore energy developments, specifically harnessing the power of the Florida Current. While it is understood that marine turtles use these waters, here we evaluate seasonal variation in sea turtle abundance and density over two years. Density of sea turtles observed within the study area ranged from 0.003 turtles km-2 in the winter of 2011 to 0.064 turtles km-2 in the spring of 2012. As a result, this assessment of marine turtles in the waters off southeast Florida quantifies their in-water abundance across seasons in this area to establish baselines and inform future management strategies of these protected species.

  18. Seasonal variation in sea turtle density and abundance in the southeast Florida current and surrounding waters

    DOE PAGESBeta

    Bovery, Caitlin M.; Wyneken, Jeanette

    2015-12-30

    Assessment and management of sea turtle populations is often limited by a lack of available data pertaining to at-sea distributions at appropriate spatial and temporal resolutions. Assessing the spatial and temporal distributions of marine turtles in an open system poses both observational and analytical challenges due to the turtles’ highly migratory nature. Surface counts of marine turtles in waters along the southern part of Florida’s east coast were made in and adjacent to the southeast portion of the Florida Current using standard aerial surveys during 2011 and 2012 to assess their seasonal presence. This area is of particular concern formore » sea turtles as interest increases in offshore energy developments, specifically harnessing the power of the Florida Current. While it is understood that marine turtles use these waters, here we evaluate seasonal variation in sea turtle abundance and density over two years. Density of sea turtles observed within the study area ranged from 0.003 turtles km-2 in the winter of 2011 to 0.064 turtles km-2 in the spring of 2012. As a result, this assessment of marine turtles in the waters off southeast Florida quantifies their in-water abundance across seasons in this area to establish baselines and inform future management strategies of these protected species.« less

  19. Seasonal Variation in Sea Turtle Density and Abundance in the Southeast Florida Current and Surrounding Waters.

    PubMed

    Bovery, Caitlin M; Wyneken, Jeanette

    2015-01-01

    Assessment and management of sea turtle populations is often limited by a lack of available data pertaining to at-sea distributions at appropriate spatial and temporal resolutions. Assessing the spatial and temporal distributions of marine turtles in an open system poses both observational and analytical challenges due to the turtles' highly migratory nature. Surface counts of marine turtles in waters along the southern part of Florida's east coast were made in and adjacent to the southeast portion of the Florida Current using standard aerial surveys during 2011 and 2012 to assess their seasonal presence. This area is of particular concern for sea turtles as interest increases in offshore energy developments, specifically harnessing the power of the Florida Current. While it is understood that marine turtles use these waters, here we evaluate seasonal variation in sea turtle abundance and density over two years. Density of sea turtles observed within the study area ranged from 0.003 turtles km-2 in the winter of 2011 to 0.064 turtles km-2 in the spring of 2012. This assessment of marine turtles in the waters off southeast Florida quantifies their in-water abundance across seasons in this area to establish baselines and inform future management strategies of these protected species. PMID:26717520

  20. Coastal sea level rise and the non-climate contribution of vertical land motion

    NASA Astrophysics Data System (ADS)

    Marcos, M.; Woppelmann, G.

    2012-12-01

    The rate of coastal sea level change and the relative importance of the non-climate contribution of vertical land movement in the Mediterranean Sea are investigated using an advanced approach of combining tide gauge and satellite altimetry data with supplemental equations from adjacent tide gauge records, suitable for enclosed basins. The sensitivity tests proved that the advanced approach is robust and accurate at the submillimeter per year level of around 0.4 mm/yr in estimating rates of vertical land movements. The average rate of coastal climate-related sea level rise in the Mediterranean Sea was consequently revisited to be of 1.7 mm/yr over the past century. The technique also enabled identifying stations displaying large rates of vertical land movements that must be taken into account when predicting future sea level rise and appraising the exposure to its impacts on populations and assets. Particular case studies will be discussed. An attempt to extend the methodology to the open ocean will be presented and the case of the North American east coast will be discussed.

  1. Seasonal Variation in Sea Turtle Density and Abundance in the Southeast Florida Current and Surrounding Waters

    PubMed Central

    Bovery, Caitlin M.; Wyneken, Jeanette

    2015-01-01

    Assessment and management of sea turtle populations is often limited by a lack of available data pertaining to at-sea distributions at appropriate spatial and temporal resolutions. Assessing the spatial and temporal distributions of marine turtles in an open system poses both observational and analytical challenges due to the turtles’ highly migratory nature. Surface counts of marine turtles in waters along the southern part of Florida’s east coast were made in and adjacent to the southeast portion of the Florida Current using standard aerial surveys during 2011 and 2012 to assess their seasonal presence. This area is of particular concern for sea turtles as interest increases in offshore energy developments, specifically harnessing the power of the Florida Current. While it is understood that marine turtles use these waters, here we evaluate seasonal variation in sea turtle abundance and density over two years. Density of sea turtles observed within the study area ranged from 0.003 turtles km-2 in the winter of 2011 to 0.064 turtles km-2 in the spring of 2012. This assessment of marine turtles in the waters off southeast Florida quantifies their in-water abundance across seasons in this area to establish baselines and inform future management strategies of these protected species. PMID:26717520

  2. Tectonic development, sedimentation and paleoceanography of the Scan Basin (southern Scotia Sea, Antarctica)

    NASA Astrophysics Data System (ADS)

    Pérez, Lara F.; Lodolo, Emanuele; Maldonado, Andrés; Hernández-Molina, F. Javier; Bohoyo, Fernando; Galindo-Zaldívar, Jesús; Lobo, F. José; Burca, Mihai

    2014-12-01

    The N-S trending Scan Basin is the easternmost deep basin north of the South Scotia Ridge, which is a geologically complex structural elevation that hosts the strike-slip boundary between the Scotia and Antarctic plates. We characterized the main morpho-structural features of the basin by analyzing the available multichannel seismic reflection profiles. The reconstruction of the seismo-stratigraphy reveals the growth patterns of the Scan Basin. Seismic data and gravity modeling support the interpretation that the basin is mainly floored by oceanic crust, however its northern and southern provinces exhibit different seismic attributes. Stratigraphic calibrations with adjacent regions together with the distribution of sedimentary units indicate that this basin was formed by rifting processes and subsequent spreading accretion from the Oligocene to the Miocene. This age attribution suggests that the Scan Basin might be one of the oldest oceanic basins of the southern Scotia Sea-possibly coeval with the Eocene-Oligocene opening of the Drake Passage. The basin is the most direct connection between the Weddell Sea and the Scotia Sea, whereas the stratigraphic features reveal the occurrence of major paleoceanographic changes. The initial phases of the evolution were influenced by mass-transport and turbidite processes of sediment supply from the nearby continental margins of the eastern tip of the Antarctic Peninsula. From the Middle Miocene to the Present-day, the eastward motion of the basin due to plate tectonic and the connection with the Weddell Sea through gateways enabled instauration of the overflow of Weddell Sea Deep Water (WSDW) into the Scan Basin. The WSDW forced the northward migration of the Circumpolar Deep Water (CDW) and became progressively dominant, controlling depositional patterns. The results that we report here should prove essential for understanding the formation of the Scotia Sea, the beginning of the Scotia Arc fragmentation, and the increasing

  3. Non-target adjacent stimuli classification improves performance of classical ERP-based brain computer interface

    NASA Astrophysics Data System (ADS)

    Ceballos, G. A.; Hernández, L. F.

    2015-04-01

    Objective. The classical ERP-based speller, or P300 Speller, is one of the most commonly used paradigms in the field of Brain Computer Interfaces (BCI). Several alterations to the visual stimuli presentation system have been developed to avoid unfavorable effects elicited by adjacent stimuli. However, there has been little, if any, regard to useful information contained in responses to adjacent stimuli about spatial location of target symbols. This paper aims to demonstrate that combining the classification of non-target adjacent stimuli with standard classification (target versus non-target) significantly improves classical ERP-based speller efficiency. Approach. Four SWLDA classifiers were trained and combined with the standard classifier: the lower row, upper row, right column and left column classifiers. This new feature extraction procedure and the classification method were carried out on three open databases: the UAM P300 database (Universidad Autonoma Metropolitana, Mexico), BCI competition II (dataset IIb) and BCI competition III (dataset II). Main results. The inclusion of the classification of non-target adjacent stimuli improves target classification in the classical row/column paradigm. A gain in mean single trial classification of 9.6% and an overall improvement of 25% in simulated spelling speed was achieved. Significance. We have provided further evidence that the ERPs produced by adjacent stimuli present discriminable features, which could provide additional information about the spatial location of intended symbols. This work promotes the searching of information on the peripheral stimulation responses to improve the performance of emerging visual ERP-based spellers.

  4. Winter sea surface temperature reflected by the TEX86 proxy in core sediments from the coastal northern South China Sea

    NASA Astrophysics Data System (ADS)

    Wei, Y.; Wang, P.; Zhao, M.; Zhang, C.

    2013-12-01

    Although TEX86 is widely used as a sea surface temperature proxy for the open ocean, the validity of TEX86 in the coastal seas has yet to be tested. In this study, three sediment cores from the coastal northwestern South China Sea (SCS) (water depth 33 m for core A9, 73 m for core, and 102 m for core A9, respectively) were analyzed using lipid biomarker approaches. The distribution of archaeal core lipids varied in core A9 and A7 but remained constant in A5. TEX86-based temperature according to Kim et al. (2010) averaged 17.2 × 0.4 οC (n=30), 20.9 × 0.3 οC (n=19) and 23.0 × 0.3 οC(n=16) in core A9, A7 and A5, respectively. These results show that temperature changed little with sediment depth at each location and increased by about 3 οC between the two adjacent locations. These are lower than the annual SST (24.5-25.7 οC) and much lower than the summer SST (>28 οC), indicating that organisms producing the TEX86-related compounds mostly lived in the winter season.

  5. High-Ti continental tholeiites from the Aznam trough, northwestern Saudi Arabia: evidence of ``abortive'' rifting in the ``embryonic'' stage of Red Sea opening

    NASA Astrophysics Data System (ADS)

    Suayah, Ismail B.; Rogers, John J. W.; Dabbagh, Mohammad E.

    1991-05-01

    The Aznam trough is a NW-trending, asymmetric graben on the northern Saudi Arabian coast of the Red Sea. Miocene or younger, high-Ti, tholeiitic basalts are exposed In the northern part of the trough. These (Aznam) basalts contain microphenocrysts of altered olivine, calcic plagioclase and clinopyroxene with subordinate amounts of ilmenite and orthopyroxene in a cryptocrystalline groundmass. A minor xenocryst/xenolith assemblage consists of quartz, sieve-textured plagioclase and a variety of crustal rock fragments. The Aznam basalts have TiO 2 contents > 3.0%, elevated 87Sr/ 86Sr ratios (0.70486-0.70546), FeO∗/MgO ratios > 2.0, and Mg-numbers between 47 and 50. They are compositionally and isotopically more evolved than tholeiites (MORB) from the Red Sea trough. Minor crustal contamination of the initial basaltic magmas is shown by the elevated Sr isotopic composition and enrichment in some LIL components. Major-element modeling indicates that the Aznam basalts can be generated by fractionation of the major phenocryst phases out of typical Red Sea MORB. Trace-element distributions are mostly consistent with this conclusion. With the exception of minor crustal contamination at Aznam, the Aznam basalts are compositionally almost identical with high-Ti basalts formed in "abortive," volcanically dormant, rifts in Iceland. Apparently the same process of magmatism and rift jumping that occurred in Iceland also occurred (and may still be occurring) in the northern Red Sea region as a short-lived embryonic rifting that is a precursor to sea-floor spreading in the Red Sea trough.

  6. Interaction between adjacent lightning discharges in clouds

    NASA Astrophysics Data System (ADS)

    Wang, Yanhui; Zhang, Guangshu; Zhang, Tong; Li, Yajun; Wu, Bin; Zhang, Tinglong

    2013-07-01

    Using a 3D lightning radiation source locating system (LLS), three pairs of associated lightning discharges (two or more adjacent lightning discharges following an arbitrary rule that their space-gap was less than 10 km and their time-gap was less than 800 ms) were observed, and the interaction between associated lightning discharges was analyzed. All these three pairs of associated lightning discharges were found to involve three or more charge regions (the ground was considered as a special charge region). Moreover, at least one charge region involved two lightning discharges per pair of associated lightning discharges. Identified from electric field changes, the subsequent lightning discharges were suppressed by the prior lightning discharges. However, it is possible that the prior lightning discharge provided a remaining discharge channel to facilitate the subsequent lightning discharge. The third case provided evidence of this possibility. Together, the results suggested that, if the charges in the main negative charge region can be consumed using artificial lightning above the main negative charge regions, lightning accidents on the ground could be greatly reduced, on the condition that the height of the main negative charge region and the charge intensity of the lower positive charge region are suitable.

  7. Variability and Trends in Sea Ice Extent and Ice Production in the Ross Sea

    NASA Technical Reports Server (NTRS)

    Comiso, Josefino; Kwok, Ronald; Martin, Seelye; Gordon, Arnold L.

    2011-01-01

    Salt release during sea ice formation in the Ross Sea coastal regions is regarded as a primary forcing for the regional generation of Antarctic Bottom Water. Passive microwave data from November 1978 through 2008 are used to examine the detailed seasonal and interannual characteristics of the sea ice cover of the Ross Sea and the adjacent Bellingshausen and Amundsen seas. For this period the sea ice extent in the Ross Sea shows the greatest increase of all the Antarctic seas. Variability in the ice cover in these regions is linked to changes in the Southern Annular Mode and secondarily to the Antarctic Circumpolar Wave. Over the Ross Sea shelf, analysis of sea ice drift data from 1992 to 2008 yields a positive rate of increase in the net ice export of about 30,000 sq km/yr. For a characteristic ice thickness of 0.6 m, this yields a volume transport of about 20 cu km/yr, which is almost identical, within error bars, to our estimate of the trend in ice production. The increase in brine rejection in the Ross Shelf Polynya associated with the estimated increase with the ice production, however, is not consistent with the reported Ross Sea salinity decrease. The locally generated sea ice enhancement of Ross Sea salinity may be offset by an increase of relatively low salinity of the water advected into the region from the Amundsen Sea, a consequence of increased precipitation and regional glacial ice melt.

  8. Caribbean Sea Level Network

    NASA Astrophysics Data System (ADS)

    von Hillebrandt-Andrade, C.; Crespo Jones, H.

    2012-12-01

    Over the past 500 years almost 100 tsunamis have been observed in the Caribbean and Western Atlantic, with at least 3510 people having lost their lives to this hazard since 1842. Furthermore, with the dramatic increase in population and infrastructure along the Caribbean coasts, today, millions of coastal residents, workers and visitors are vulnerable to tsunamis. The UNESCO IOC Intergovernmental Coordination Group for Tsunamis and other Coastal Hazards for the Caribbean and Adjacent Regions (CARIBE EWS) was established in 2005 to coordinate and advance the regional tsunami warning system. The CARIBE EWS focuses on four areas/working groups: (1) Monitoring and Warning, (2) Hazard and Risk Assessment, (3) Communication and (4) Education, Preparedness and Readiness. The sea level monitoring component is under Working Group 1. Although in the current system, it's the seismic data and information that generate the initial tsunami bulletins, it is the data from deep ocean buoys (DARTS) and the coastal sea level gauges that are critical for the actual detection and forecasting of tsunamis impact. Despite multiple efforts and investments in the installation of sea level stations in the region, in 2004 there were only a handful of sea level stations operational in the region (Puerto Rico, US Virgin Islands, Bermuda, Bahamas). Over the past 5 years there has been a steady increase in the number of stations operating in the Caribbean region. As of mid 2012 there were 7 DARTS and 37 coastal gauges with additional ones being installed or funded. In order to reach the goal of 100 operational coastal sea level stations in the Caribbean, the CARIBE EWS recognizes also the importance of maintaining the current stations. For this, a trained workforce in the region for the installation, operation and data analysis and quality control is considered to be critical. Since 2008, three training courses have been offered to the sea level station operators and data analysts. Other

  9. Southwest Monsoon Circulation and Environments of Recent Planktonic Foraminifera in the Northwestern Arabian Sea

    NASA Astrophysics Data System (ADS)

    Brock, John C.; McClain, Charles R.; Anderson, David M.; Prell, Warren L.; Hay, William W.

    1992-12-01

    Digital hydrographic data combined with satellite thermal infrared and visible band remote sensing provide a synoptic climatological view of the shallow planktonic environment. This paper uses wind, hydrographic, and ocean remote sensing data to examine southwest monsoon controls on the foraminiferal faunal composition of Recent seafloor sediments of the northwestern Arabian Sea. Ekman pumping resulting in open-ocean upwelling and coastal upwelling create two distinctly different mixed layer plankton environments in the northwestern Arabian Sea during the summer monsoon. Open-sea upwelling to the northwest of the mean July position of the Findlater Jet axis yields a mixed layer environment with temperatures of less than 25°C to about 26.5°C, phytoplankton pigment concentrations between 1.5 and 5.0 mg/m³, and mixed layer depths less than 50 m. Convergence in the Ekman layer in the central Arabian Sea drives the formation of a mixed layer that is greater than 50 m thick, warmer than about 26.5°C, and has phytoplankton pigment concentrations generally below 2.0 mg/m³. Coastal upwelling creates an extremely eutrophic plankton environment that persists over and immediately adjacent to the Omani shelf and undergoes significant offshore transport only within topographically induced coastal squirts. The foraminiferal faunal composition of upper Pleistocene deep-sea sediments of the northwestern Arabian Sea are mainly controlled by vertical nutrient fluxes caused by Ekman pumping, not coastal upwelling. Transfer functions for late Pleistocene mixed layer depth, temperature, and chlorophyll have been obtained through factor analysis and nonlinear multiple regression between late summer mixed layer environment and Recent sediment faunal observations.

  10. Petroleum basins of Sakhalin and adjacent shelf

    SciTech Connect

    Mavrinski, Y.; Koblov, E. )

    1993-09-01

    Sixty-seven oil and gas fields have been discovered on Sakhalin and the adjacent shelf but the distribution of fields is uneven in north Sakhalin, south Sakhalin, and the Tatar basins. The sedimentary cover is composed of sandy, clayey, and siliceous rocks, with volcanogenic and coal-bearing deposits of Upper Cretaceous, Paleogene, and Neogene 8-12 km thick. Marine clayey and siliceous oil source rocks are regionally developed in the section at different stratigraphic levels; the organic matter is of mixed type and the content varies from 0.5 to 1.5%. The upper Oligocene and middle-upper Miocene source rocks in the north Sakhalin basin are typical, and the organic carbon content ranges from 1 to 5%. The level of organic matter catagenesis and conversion into hydrocarbons is high because of the high differential geothermal gradient in the basins, 30-50[degrees]C per km. Porous sandstones in the Miocene form the reservoirs in all fields with the exception of Okruzhnoye, where the pay zone is a siliceous claystone. Growth-fault rollovers and anticlines form the main traps ranging in area from 5 to 300 km[sup 2], with amplitudes between 100 and 600 m. both stratigraphic and structural traps have been identified. Considerable volumes of reserves are associated with the Miocene deposits of north Sakhalin, which are characterized by an optimum combination of oil source rocks, focused migration paths, and thick sequences of reservoirs and cap rocks. Six large fields have been discovered in the past 15 yr. Oil and condensate reserves stand at over 300 million MT, and gas reserves are about 900 billion m[sup 3].

  11. Red Sea

    Atmospheric Science Data Center

    2013-04-16

    article title:  The Red Sea     View Larger Image ... Imaging SpectroRadiometer (MISR) image of the Red Sea was acquired on August 13, 2000. Located between the East African coast and the Saudi Arabian peninsula, the Red Sea got its name because the blooms of a type of algae,  Trichodesmium ...

  12. Bering Sea

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Much of the Bering Sea is clear in this SeaWiFS image. The large expanse of bright aquamarine water is clearly visible. Credit: Provided by the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

  13. Bering Sea

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The skies of the Bering Sea were relatively clear again in this SeaWiFS image showing a band of aquamarine colored water. Credit: Provided by the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

  14. Geophysical observations on northern part of Georges Bank and adjacent basins of Gulf of Maine

    USGS Publications Warehouse

    Oldale, R.N.; Hathaway, J.C.; Dillon, William P.; Hendricks, J.D.; Robb, James M.

    1974-01-01

    Continuous-seismic-reflection and magnetic-intensity profiles provide data for inferences about the geology of the northern part of Georges Bank and the basins of the Gulf of Maine adjacent to the bank. Basement is inferred to be mostly sedimentary and volcanic rocks of Paleozoic age that were metamorphosed and intruded locally by felsic and mafic plutons near the end of the Paleozoic Era. During Late Triassic time, large fault basins formed within the Gulf of Maine and probably beneath Georges Bank. The fault basins and a possible major northeast-trending fault zone beneath the northern part of the bank probably formed as a result of the opening Atlantic during the Mesozoic. Nonmarine sediments, associated with mafic flows and intrusive rocks, were deposited in the fault basins as they formed. The upper surface of the Triassic and pre-Triassic rocks that comprise basement is an unconformity that makes up much of the bottom of the Gulf of Maine. Depth to the basement surface beneath the gulf differ greatly because of fluvial erosion in Tertiary time and glacial erosion in Pleistocene time. Beneath the northern part of Georges Bank the basement surface is smoother and slopes southward. Prominent valleys, cut before Late Cretaceous time, are present beneath this part of the bank. Cretaceous, Tertiary, and possibly Jurassic times were characterized by episodes of coastal-plain deposition and fluvial erosion. During this time a very thick wedge of sediment, mostly of Jurassic(?) and Cretaceous ages, was deposited on the shelf. Major periods of erosion took place at the close of the Cretaceous and during the Pliocene. Fluvial erosion during the Pliocene removed much of the coastal-plain sedimentary wedge and formed the Gulf of Maine. Pleistocene glaciers eroded all but a few remnants of the coastal-plain sediments within the gulf and deposited a thick section of drift against the north slope of Georges Bank and a thin veneer of outwash on the bank. Marine sediments were

  15. Contrasting microbial assemblages in adjacent water masses associated with the East Australian Current.

    PubMed

    Seymour, Justin R; Doblin, Martina A; Jeffries, Thomas C; Brown, Mark V; Newton, Kelly; Ralph, Peter J; Baird, Mark; Mitchell, James G

    2012-10-01

    Different oceanographic provinces host discrete microbial assemblages that are adapted to local physicochemical conditions. We sequenced and compared the metagenomes of two microbial communities inhabiting adjacent water masses in the Tasman Sea, where the recent strengthening of the East Australian Current (EAC) has altered the ecology of coastal environments. Despite the comparable latitude of the samples, significant phylogenetic differences were apparent, including shifts in the relative frequency of matches to Cyanobacteria, Crenarchaeota and Euryarchaeota. Fine-scale variability in the structure of SAR11, Prochlorococcus and Synechococcus populations, with more matches to 'warm-water' ecotypes observed in the EAC, indicates the EAC may drive an intrusion of tropical microbes into temperate regions of the Tasman Sea. Furthermore, significant shifts in the relative importance of 17 metabolic categories indicate that the EAC prokaryotic community has different physiological properties than surrounding waters. PMID:23760900

  16. Sea ice and oceanic processes on the Ross Sea continental shelf

    NASA Technical Reports Server (NTRS)

    Jacobs, S. S.; Comiso, J. C.

    1989-01-01

    The spatial and temporal variability of Antarctic sea ice concentrations on the Ross Sea continental shelf have been investigated in relation to oceanic and atmospheric forcing. Sea ice data were derived from Nimbus 7 scanning multichannel microwave radiometer (SMMR) brightness temperatures from 1979-1986. Ice cover over the shelf was persistently lower than above the adjacent deep ocean, averaging 86 percent during winter with little month-to-month of interannual variability. The large spring Ross Sea polynya on the western shelf results in a longer period of summer insolation, greater surface layer heat storage, and later ice formation in that region the following autumn.

  17. Remotely-sensed chlorophyll a observations of the northern Red Sea indicate seasonal variability and influence of coastal reefs

    NASA Astrophysics Data System (ADS)

    Acker, James; Leptoukh, Gregory; Shen, Suhung; Zhu, Tong; Kempler, Steven

    The biological dynamics of the open northern Red Sea (21.5°-27.5° N, 33.5°-40° E) have not been studied extensively, due in part to both the inaccessibility of this desert region and political considerations. Remotely-sensed chlorophyll a data therefore provide a framework to investigate the primary patterns of biological activity in this oceanic basin. Monthly chlorophyll a data from the 8-year Sea-viewing Wide Field-of-View sensor (SeaWiFS) mission, and data from the Moderate Resolution Imaging Spectroradiometer (MODIS), were analyzed with the Goddard Earth Sciences Data and Information Services Center (GES DISC) online data analysis system "Giovanni". The data indicate that despite the normal low chlorophyll a concentrations (0.1-0.2 mg m - 3 ) in these oligotrophic waters, there is a characteristic seasonal bloom in March-April in the northernmost open Red Sea (24° to 27.5° N) concurrent with minimum sea surface temperature. The location of the highest chlorophyll concentrations is consistent with a linear box model [Eshel, G., and Naik, N.H., 1997. Climatological coastal jet collision, intermediate water formation, and the general circulation of the Red Sea. J. Phys. Oceanogr. 27(7), 1233-1257.] of Red Sea circulation. Two years in the data set exhibited a different seasonal cycle consisting of a relatively weak northern spring bloom and elevated chlorophyll concentrations to the south (21.5° to 24° N). The data also indicate that large coral reef complexes may be sources of either nutrients or chlorophyll-rich detritus and sediment, enhancing chlorophyll a concentration in waters adjacent to the reefs.

  18. The speciation of marine particulate iron adjacent to active and passive continental margins

    NASA Astrophysics Data System (ADS)

    Lam, Phoebe J.; Ohnemus, Daniel C.; Marcus, Matthew A.

    2012-03-01

    We use synchrotron-based chemical-species mapping techniques to compare the speciation of suspended (1-51 μm) marine particulate iron collected in two open ocean environments adjacent to active and passive continental margins. Chemical-species mapping provides speciation information for heterogeneous environmental samples, and is especially good for detecting spectroscopically distinct trace minerals and species that could not be detectable by other methods. The average oxidation state of marine particulate iron determined by chemical-species mapping is comparable to that determined by standard bulk X-ray Absorption Near Edge Structure spectroscopy. Using chemical-species mapping, we find that up to 43% of particulate Fe in the Northwest Pacific at the depth of the adjacent active continental margin is in the Fe(II) state, with the balance Fe(III). In contrast, particulate iron in the eastern tropical North Atlantic, which receives the highest dust deposition on Earth and is adjacent to a passive margin, is dominated by weathered and oxidized Fe compounds, with Fe(III) contributing 90% of total iron. The balance is composed primarily of Fe(II)-containing species, but we detected individual pyrite particles in some samples within an oxygen minimum zone in the upper thermocline. Several lines of evidence point to the adjacent Mauritanian continental shelf as the source of pyrite to the water column. The speciation of suspended marine particulate iron reflects the mineralogy of iron from the adjacent continental margins. Since the solubility of particulate iron has been shown to be a function of its speciation, this may have implications for the bioavailability of particulate iron adjacent to passive compared to active continental margins.

  19. Compositional Comparison of Iceland Rift Zones and Adjacent Portions of the Mid-Atlantic Ridge.

    NASA Astrophysics Data System (ADS)

    Kelley, D.; Barton, M.

    2007-12-01

    Iceland is a portion of the Mid-Atlantic Ridge (MAR) that has been built by anomalous crustal production throughout the 55ma spreading history of the opening of the Atlantic Ocean. The anomalously thick crust of Iceland contains the subaerial traces of the MAR which are the volcanically active rift zones. From the south, the Reykjanes Ridge (RR) continues on land as the Western Volcanic Zone (WVZ). In the north, the Northern Volcanic Zone (NVZ) traces into the sea where it offset from the Kolbeinsey Ridge (KR) by the Tjornnes Fracture Zone (TVZ). We report the results of petrologic comparison of the WVZ, the EVZ, and the NVZ of Iceland and the adjacent portions of the MAR - the RR and the KR. The EVZ, WVZ, and NVZ have been shown to have similar crustal structures with ~20 km thick crust thickening toward the hotspot in central Iceland with magma chambers located at the base of the crust and at some depth in the upper crust. Likewise, the KR and RR have melt chambers at the base of and within the crust. Melt compositions have been compared using a filtered database of 588 glass analyses from 29 localities throughout the rift zones, 57 glass analyses from the KR, and 521 glass analyses from the RR. This is the first such study carried out with such an extensive data set. Compositions are similar between the NVZ and WVZ with SiO2 wt.% of 49.0, and 48.6, MgO wt.% of 7.9, and 7.5, and FeOT wt.% of 10.9, and 11.7 respectively. The EVZ which is considered to be a propagating rift is a bit different with SiO2 wt.% of 49.4, MgO wt.% of 5.9, and FeOT wt.% of 13.8. The NVZ and WVZ have also been compared with their respectively adjacent ridge segments, the KR (SiO2 50.3 wt.%, MgO 6.9 wt.%, and FeOT 12.0 wt.%), and the RR (SiO2 50.8 wt.%, MgO 6.9 wt.%, and FeOT 12.3 wt.%). Mg#s for the NVZ and the WVZ are 0.56, and .053 respectively while the Mg# for both the KR and RR is 0.50. For further comparison, a database of 9035 glass analyses from mid-ocean ridge basalts worldwide

  20. Ius Chasma Tributary Valleys and Adjacent Plains

    NASA Technical Reports Server (NTRS)

    2006-01-01

    This image covers valley tributaries of Ius Chasma, as well as the plains adjacent to the valleys. Ius Chasma is one of several canyons that make up the Valles Marineris canyon system. Valles Marineris likely formed by extension associated with the growth of the large volcanoes and topographic high of Tharsis to the northwest. As the ground was pulled apart, large and deep gaps resulted in the valleys seen in the top and bottom of this HiRISE image. Ice that was once in the ground could have also melted to create additional removal of material in the formation of the valleys. HiRISE is able to see the rocks along the walls of both these valleys and also impact craters in the image. Rock layers that appear lower down in elevation appear rougher and are shedding boulders. Near the top of the walls and also seen in patches along the smooth plains are brighter layers. These brighter layers are not shedding boulders so they must represent a different kind of rock formed in a different kind of environment than those further down the walls. Because they are highest in elevation, the bright layers are youngest in age. HiRISE is able to see dozens of the bright layers, which are perhaps only a meter in thickness. Darker sand dunes and ripples cover most of the plains and fill the floors of impact craters.

    Image PSP_001351_1715 was taken by the High Resolution Imaging Science Experiment (HiRISE) camera onboard the Mars Reconnaissance Orbiter spacecraft on November 9, 2006. The complete image is centered at -8.3 degrees latitude, 275.4 degrees East longitude. The range to the target site was 254.3 km (158.9 miles). At this distance the image scale ranges from 25.4 cm/pixel (with 1 x 1 binning) to 101.8 cm/pixel (with 4 x 4 binning). The image shown here has been map-projected to 25 cm/pixel and north is up. The image was taken at a local Mars time of 3:32 PM and the scene is illuminated from the west with a solar incidence angle of 59 degrees, thus the sun was about

  1. Geology of Barents Sea

    SciTech Connect

    Riis, F.; Vollset, J.

    1984-09-01

    The Barents Sea is situated on the continental shelf between Norway, the Spitsbergen Islands, and Novaya Zemlya. The main structural framework of the area was formed during the Caledonian and Hercynian orogenies, whereas the western parts were reactivated by the Kimmerian and Alpine orogenies. Because of the complex opening of the Greenland Norwegian Sea, important tertiary reactivation of Mesozoic normal faults occurred along southwest-northeast-trending systems of wrench faults. Owing to substantial erosion in the late Tertiary, the subsidence history and thermal development are more difficult to unravel in this area than in other places along the Norwegian Shelf. The erosion products were deposited in a huge sedimentary wedge extending onto the oceanic crust. The hydrocarbon discoveries in the Troms area in the southern part of the Barents Sea are encouraging for further exploration. However, the petroleum potential for large areas is not well known at this stage.

  2. 76 FR 68658 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch in the Bering Sea...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-07

    ... Economic Zone Off Alaska; Pacific Ocean Perch in the Bering Sea Subarea of the Bering Sea and Aleutian... is opening directed fishing for Pacific ocean perch in the Bering Sea subarea of the Bering Sea and... Pacific ocean perch specified for the Bering Sea subarea of the Bering Sea and Aleutian Islands...

  3. Torsion-Mediated Interaction between Adjacent Genes

    PubMed Central

    Meyer, Sam; Beslon, Guillaume

    2014-01-01

    DNA torsional stress is generated by virtually all biomolecular processes involving the double helix, in particular transcription where a significant level of stress propagates over several kilobases. If another promoter is located in this range, this stress may strongly modify its opening properties, and hence facilitate or hinder its transcription. This mechanism implies that transcribed genes distant of a few kilobases are not independent, but coupled by torsional stress, an effect for which we propose the first quantitative and systematic model. In contrast to previously proposed mechanisms of transcriptional interference, the suggested coupling is not mediated by the transcription machineries, but results from the universal mechanical features of the double-helix. The model shows that the effect likely affects prokaryotes as well as eukaryotes, but with different consequences owing to their different basal levels of torsion. It also depends crucially on the relative orientation of the genes, enhancing the expression of eukaryotic divergent pairs while reducing that of prokaryotic convergent ones. To test the in vivo influence of the torsional coupling, we analyze the expression of isolated gene pairs in the Drosophila melanogaster genome. Their orientation and distance dependence is fully consistent with the model, suggesting that torsional gene coupling may constitute a widespread mechanism of (co)regulation in eukaryotes. PMID:25188032

  4. View of north side from exterior stairs of adjacent building, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of north side from exterior stairs of adjacent building, bottom cut off by fringed buildings, view facing south-southwest - U.S. Naval Base, Pearl Harbor, Industrial X-Ray Building, Off Sixth Street, adjacent to and south of Facility No. 11, Pearl City, Honolulu County, HI

  5. Learning Non-Adjacent Regularities at Age 0 ; 7

    ERIC Educational Resources Information Center

    Gervain, Judit; Werker, Janet F.

    2013-01-01

    One important mechanism suggested to underlie the acquisition of grammar is rule learning. Indeed, infants aged 0 ; 7 are able to learn rules based on simple identity relations (adjacent repetitions, ABB: "wo fe fe" and non-adjacent repetitions, ABA: "wo fe wo", respectively; Marcus et al., 1999). One unexplored issue is…

  6. Delayed Acquisition of Non-Adjacent Vocalic Distributional Regularities

    ERIC Educational Resources Information Center

    Gonzalez-Gomez, Nayeli; Nazzi, Thierry

    2016-01-01

    The ability to compute non-adjacent regularities is key in the acquisition of a new language. In the domain of phonology/phonotactics, sensitivity to non-adjacent regularities between consonants has been found to appear between 7 and 10 months. The present study focuses on the emergence of a posterior-anterior (PA) bias, a regularity involving two…

  7. New Aerosol Models for the Retrieval of Aerosol Optical Thickness and Normalized Water-Leaving Radiances from the SeaWiFS and MODIS Sensors Over Coastal Regions and Open Oceans

    NASA Technical Reports Server (NTRS)

    Ahmad, Ziauddin; Franz, Bryan A.; McClain, Charles R.; Kwiatkowska, Ewa J.; Werdell, Jeremy; Shettle, Eric P.; Holben, Brent N.

    2010-01-01

    We describe the development of a new suite of aerosol models for the retrieval of atmospheric and oceanic optical properties from the SeaWiFs and MODIS sensors, including aerosol optical thickness (tau), angstrom coefficient (alpha), and water-leaving radiance (L(sub w)). The new aerosol models are derived from Aerosol Robotic Network (AERONET) observations and have bimodal lognormal distributions that are narrower than previous models used by the Ocean Biology Processing Group. We analyzed AERONET data over open ocean and coastal regions and found that the seasonal variability in the modal radii, particularly in the coastal region, was related to the relative humidity, These findings were incorporated into the models by making the modal radii, as well as the refractive indices, explicitly dependent on relative humidity, From those findings, we constructed a new suite of aerosol models. We considered eight relative humidity values (30%, 50%, 70%, 75%, 80%, 85%, 90%. and 95%) and, for each relative humidity value, we constructed ten distributions by varying the fine-mode fraction from zero to 1. In all. 80 distributions (8Rh x 10 fine-mode fractions) were created to process the satellite data. We. also assumed that the coarse-mode particles were nonabsorbing (sea salt) and that all observed absorptions were entirely due to fine-mode particles. The composition of fine mode was varied to ensure that the new models exhibited the same spectral dependence of single scattering albedo as observed in the AERONET data,

  8. The dynamics of grey seals ( Halichoerus grypus) off Amrum in the south-eastern North Sea — evidence of an open population

    NASA Astrophysics Data System (ADS)

    Abt, Kai F.; Hoyer, Nils; Koch, Lothar; Adelung, Dieter

    2002-02-01

    Grey seals ( Halichoerus grypus) have been extinct in the south-eastern North Sea for centuries. Only in recent decades have they re-established a few colonies, the first of which was located on a group of sand bars off the German island of Amrum. Based on frequent counts from aircraft and boats in 1976-2000, and a photo-identification program in 1997, we investigated seasonal dynamics, trends in abundance, pup production, and pup survival in this population. Numbers of hauled-out seals were highest in spring, with a peak of 70-100 in late March or early April, and usually lower than 40 from late May to late January, including the winter breeding season. Both spring and summer counts indicated an average increase of 4-5% per year. Annual pup production was 3-10 in 1988-1995 and 9-13 in 1996-1999, suggesting a breeding stock of only about half the minimum total population size, i.e. 137 individually recognised seals in 1997. The estimated survival of pups until weaning seemed high enough to support autochthonous increase, and hence suggested a self-sustaining breeding stock at least until the late 1990s. Pup survival declined, however, from 95-100% in 1988-1991 to 60-70% in 1992-1999, probably due to erosion of the sand bars. From (i) the relative excess of hauled-out seals in spring, as compared to the phenology of stocks in the western North Sea, (ii) turnover and net loss of individuals during the spring and summer of 1997, as indicated by photo-ID records, and (iii) the low apparent per capita birth rate, we suggest that grey seals off Amrum split into a resident breeding stock and a similar or higher number of seals immigrating outside the breeding season. The latter may originate from larger colonies in the southern and western North Sea, and return there for breeding. In the future, grey seals currently breeding off Amrum may eventually leave the area because of deteriorating conditions. However, a decline of numbers occurring in spring and summer would not

  9. Wood decay at sea

    NASA Astrophysics Data System (ADS)

    Charles, François; Coston-Guarini, Jennifer; Guarini, Jean-Marc; Fanfard, Sandrine

    2016-08-01

    The oceans and seas receive coarse woody debris since the Devonian, but the kinetics of wood degradation remains one of many unanswered questions about the fate of driftwood in the marine environment. A simple gravimetric experiment was carried out at a monitoring station located at the exit of a steep, forested Mediterranean watershed in the Eastern Pyrenees. The objective was to describe and quantify, with standardized logs (in shape, structure and constitution), natural degradation of wood in the sea. Results show that the mass decrease of wood logs over time can be described by a sigmoidal curve. The primary process of wood decay observed at the monitoring station was due to the arrival and installation of wood-boring species that consumed more than half of the total wood mass in six months. Surprisingly, in a region where there is little remaining wood marine infrastructure, "shipworms", i.e. xylophagous bivalves, are responsible for an important part of this wood decay. This suggests that these communities are maintained probably by a frequent supply of a large quantity of riparian wood entering the marine environment adjacent to the watershed. By exploring this direct link between terrestrial and marine ecosystems, our long term objective is to determine how these supplies of terrestrial organic carbon can sustain wood-based marine communities as it is observed in the Mediterranean Sea.

  10. New aerosol models for the retrieval of aerosol optical thickness and normalized water-leaving radiances from the SeaWiFS and MODIS sensors over coastal regions and open oceans.

    PubMed

    Ahmad, Ziauddin; Franz, Bryan A; McClain, Charles R; Kwiatkowska, Ewa J; Werdell, Jeremy; Shettle, Eric P; Holben, Brent N

    2010-10-10

    We describe the development of a new suite of aerosol models for the retrieval of atmospheric and oceanic optical properties from the SeaWiFS and MODIS sensors, including aerosol optical thickness (τ), angstrom coefficient (α), and water-leaving radiance (L(w)). The new aerosol models are derived from Aerosol Robotic Network (AERONET) observations and have bimodal lognormal distributions that are narrower than previous models used by the Ocean Biology Processing Group. We analyzed AERONET data over open ocean and coastal regions and found that the seasonal variability in the modal radii, particularly in the coastal region, was related to the relative humidity. These findings were incorporated into the models by making the modal radii, as well as the refractive indices, explicitly dependent on relative humidity. From these findings, we constructed a new suite of aerosol models. We considered eight relative humidity values (30%, 50%, 70%, 75%, 80%, 85%, 90%, and 95%) and, for each relative humidity value, we constructed ten distributions by varying the fine-mode fraction from zero to 1. In all, 80 distributions (8 Rh×10 fine-mode fractions) were created to process the satellite data. We also assumed that the coarse-mode particles were nonabsorbing (sea salt) and that all observed absorptions were entirely due to fine-mode particles. The composition of the fine mode was varied to ensure that the new models exhibited the same spectral dependence of single scattering albedo as observed in the AERONET data. The reprocessing of the SeaWiFS data show that, over deep ocean, the average τ(865) values retrieved from the new aerosol models was 0.100±0.004, which was closer to the average AERONET value of 0.086±0.066 for τ(870) for the eight open-ocean sites used in this study. The average τ(865) value from the old models was 0.131±0.005. The comparison of monthly mean aerosol optical thickness retrieved from the SeaWiFS sensor with AERONET data over Bermuda and

  11. Bowhead whale acoustic activity in the southeast Beaufort Sea during late summer 2008-2010.

    PubMed

    Charif, Russell A; Rahaman, Ashakur; Muirhead, Charles A; Pitzrick, Michael S; Warde, Ann M; Hall, James; Pyć, Cynthia; Clark, Christopher W

    2013-12-01

    Autonomous passive acoustic recorders were deployed to record sounds of bowhead whales (Balaena mysticetus) in the southeast Beaufort Sea for periods of 30-55 days during the late summer, open-water seasons of 2008-2010. Recordings were made in three areas licensed for hydrocarbon exploration, spanning the continental slope and adjacent outer shelf, and in a shallow inner-shelf area where bowheads have been observed congregating to feed in recent decades. Bowhead sounds were counted in samples comprising 10% of each recorded hour. In mid-August and September in all 3 years, the rate of bowhead calling at outer shelf sites exceeded that at adjacent continental slope sites by one to two orders of magnitude. Higher rates of calling occurred on the slope in late July and early August than at later dates. Calling rates varied by an order of magnitude between years in the one area that was monitored in different years. The highest rates of calling occurred on the inner shelf, offshore of the northern Tuktoyaktuk Peninsula. These trends are consistent with patterns of habitat use previously reported from aerial surveys in this and nearby areas of the Beaufort Sea and with the results of satellite tagging studies. PMID:25669244

  12. Muscular cholinesterase and lactate dehydrogenase activities in deep-sea fish from the NW Mediterranean.

    PubMed

    Koenig, Samuel; Solé, Montserrat

    2014-03-01

    Organisms inhabiting submarine canyons can be potentially exposed to higher inputs of anthropogenic chemicals than their counterparts from the adjacent areas. To find out to what extend this observation applies to a NW Mediterranean canyon (i.e. Blanes canyon) off the Catalan coast, four deep-sea fish species were collected from inside the canyon (BC) and the adjacent open slope (OS). The selected species were: Alepocephalus rostratus, Lepidion lepidion, Coelorinchus mediterraneus and Bathypterois mediterraneus. Prior to the choice of an adequate sentinel species, the natural variation of the selected parameters (biomarkers) in relation to factors such as size, sex, sampling depth and seasonality need to be characterised. In this study, the activities of cholinesterases (ChEs) and lactate dehydrogenase (LDH) enzymes were determined in the muscle of the four deep-sea fish. Of all ChEs, acetylcholinesterase (AChE) activity was dominant and selected for further monitoring. Overall, AChE activity exhibited a significant relationship with fish size whereas LDH activity was mostly dependent on the sex and gonadal development status, although in a species-dependent manner. The seasonal variability of LDH activity was more marked than for AChE activity, and inside-outside canyon (BC-OS) differences were not consistent in all contrasted fish species, and in fact they were more dependent on biological traits. Thus, they did not suggest a differential stress condition between sites inside and outside the canyon. PMID:24296242

  13. Projecting future sea level

    USGS Publications Warehouse

    Cayan, Daniel R.; Bromirski, Peter; Hayhoe, Katharine; Tyree, Mary; Dettinger, Mike; Flick, Reinhard

    2006-01-01

    California’s coastal observations and global model projections indicate that California’s open coast and estuaries will experience increasing sea levels over the next century. Sea level rise has affected much of the coast of California, including the Southern California coast, the Central California open coast, and the San Francisco Bay and upper estuary. These trends, quantified from a small set of California tide gages, have ranged from 10–20 centimeters (cm) (3.9–7.9 inches) per century, quite similar to that estimated for global mean sea level. So far, there is little evidence that the rate of rise has accelerated, and the rate of rise at California tide gages has actually flattened since 1980, but projections suggest substantial sea level rise may occur over the next century. Climate change simulations project a substantial rate of global sea level rise over the next century due to thermal expansion as the oceans warm and runoff from melting land-based snow and ice accelerates. Sea level rise projected from the models increases with the amount of warming. Relative to sea levels in 2000, by the 2070–2099 period, sea level rise projections range from 11–54 cm (4.3–21 in) for simulations following the lower (B1) greenhouse gas (GHG) emissions scenario, from 14–61 cm (5.5–24 in) for the middle-upper (A2) emission scenario, and from 17–72 cm (6.7–28 in) for the highest (A1fi) scenario. In addition to relatively steady secular trends, sea levels along the California coast undergo shorter period variability above or below predicted tide levels and changes associated with long-term trends. These variations are caused by weather events and by seasonal to decadal climate fluctuations over the Pacific Ocean that in turn affect the Pacific coast. Highest coastal sea levels have occurred when winter storms and Pacific climate disturbances, such as El Niño, have coincided with high astronomical tides. This study considers a range of projected future

  14. Seismic reflection characteristics of glacial and glacimarine sediment in the Gulf of Alaska and adjacent fjords

    USGS Publications Warehouse

    Carlson, P.R.

    1989-01-01

    Glaciation together with tectonism have been dominant factors affecting sedimentation in the Gulf of Alaska area from at least the late Miocene throughout the Quaternary. The effects of tectonism are apparent in high mountains that border the gulf, raised terraces of Middleton Island and the eastern gulf coastal zone, and numerous active faults and related earthquakes. Glacial evidence includes magnificent glaciers and their onshore deposits, spectacular fjords, large sea valleys incised in the continental shelf, submarine morainal ridges at mouths of bays and sea valleys, and thick glacimarine sedimentary sequences (diamicts) that are exposed onshore and at the sea floor along the outer shelf. Seismic-reflection profiling and sampling of the uppermost marine sedimentary sequences in the Gulf of Alaska and adjacent fjords and bays have allowed identification of three discrete glacially related stratigraphic units. These units were delineated on the basis of seismic signature, geometry, physiographic location, stratigraphic position, and sedimentologic characteristics. The oldest unit, a Quaternary diamict, is portrayed on seismic profiles by irregular, discontinuous reflections. This unit probably includes till, outwash and glacimarine sediment. A geographically restricted unit, one incorporating Holocene end moraines at bay mouths and associated with some sea valleys, consists of jumbled masses of discontinuous reflections and very irregular surface morphology. The youngest unit, a blanket of Holocene sand to clayey silt prograding as a sediment wedge across the shelf, contains nearly horizontal, parallel reflections except where disrupted by mass movement. Although seismic-reflection data alone cannot provide definitive proof of the presence of glacial sediment, when combined with sea-floor sampling, seismic profiling is a powerful tool for determining the continuity of marine sedimentary units and relationships to past and modern glaciers. ?? 1989.

  15. Thermoelastic response of thin metal films and their adjacent materials

    SciTech Connect

    Kang, S.; Yoon, Y.; Kim, J.; Kim, W.

    2013-01-14

    A pulsed laser beam applied to a thin metal film is capable of launching an acoustic wave due to thermal expansion. Heat transfer from the thin metal film to adjacent materials can also induce thermal expansion; thus, the properties of these adjacent materials (as well as the thin metal film) should be considered for a complete description of the thermoelastic response. Here, we show that adjacent materials with a small specific heat and large thermal expansion coefficient can generate an enhanced acoustic wave and we demonstrate a three-fold increase in the peak pressure of the generated acoustic wave on substitution of parylene for polydimethylsiloxane.

  16. Contrasts in Arctic shelf sea-ice regimes and some implications: Beaufort Sea versus Laptev Sea

    USGS Publications Warehouse

    Reimnitz, E.; Dethleff, D.; Nurnberg, D.

    1994-01-01

    The winter ice-regime of the 500 km) from the mainland than in the Beaufort Sea. As a result, the annual freeze-up does not incorporate old, deep-draft ice, and with a lack of compression, such deep-draft ice is not generated in situ, as on the Beaufort Sea shelf. The Laptev Sea has as much as 1000 km of fetch at the end of summer, when freezing storms move in and large (6 m) waves can form. Also, for the first three winter months, the polynya lies inshore at a water depth of only 10 m. Turbulence and freezing are excellent conditions for sediment entrainment by frazil and anchor ice, when compared to conditions in the short-fetched Beaufort Sea. We expect entrainment to occur yearly. Different from the intensely ice-gouged Beaufort Sea shelf, hydraulic bedforms probably dominate in the Laptev Sea. Corresponding with the large volume of ice produced, more dense water is generated in the Laptev Sea, possibly accompanied by downslope sediment transport. Thermohaline convection at the midshelf polynya, together with the reduced rate of bottom disruption by ice keels, may enhance benthic productivity and permit establishment of open-shelf benthic communities which in the Beaufort Sea can thrive only in the protection of barrier islands. Indirect evidence for high benthic productivity is found in the presence of walrus, who also require year-round open water. By contrast, lack of a suitable environment restricts walrus from the Beaufort Sea, although over 700 km farther to the south. We could speculate on other consequences of the different ice regimes in the Beaufort and Laptev Seas, but these few examples serve to point out the dangers of exptrapolating from knowledge gained in the North American Arctic to other shallow Arctic shelf settings. ?? 1994.

  17. Beaufort-Chukchi Seas summer and fall ice margin data from Seasat - Conditions with similarities to the Labrador Sea

    NASA Technical Reports Server (NTRS)

    Carsey, Frank D.; Pihos, Greg

    1989-01-01

    The margin of the sea-ice pack of the Beaufort and Chukchi Seas is examined using the microwave data from Seasat taken during the summer to early fall, July 4 through October 8, 1978, and the observations are compared to the analogous observations taken in LIMEX'87. The sensors used are synthetic-aperture radar (SAR), the Seasat-A scatterometer system, and the Scanning Multichannel Microwave Radiometer. The examination indicates that the ice edge in summer and early fall is compact; that is, in most cases the pack undergoes an abrupt change in ice concentration from zero over open water to a substantial value (over 70 percent) in the marginal ice zone. This change takes place over the space of a few kilometers. Adjacent to the edge there is a zone of intermediate ice concentration 50-100-km wide. In late summer there is a band of ice at the edge which is largely featureless in the 25-m resolution of the Seasat SAR and is taken to be ice cakes with diameters less than 100 m. Eddylike structures seem to be present in the margin on scales from 5-200 km; bands and tadpole streamers are also observable. All three instruments locate the ice edge with varying degrees of precision.

  18. 73. PASSAGE ADJACENT TO ROOM 232, EAST WING, SECOND FLOOR, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    73. PASSAGE ADJACENT TO ROOM 232, EAST WING, SECOND FLOOR, LOOKING WEST BY NORTHWEST, SHOWING EASTERNMOST ARCH OF FORMER GREAT HALL NORTH ARCADE - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  19. View of viaduct, looking SE from roof of adjacent parking ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of viaduct, looking SE from roof of adjacent parking garage. - Mulberry Street Viaduct, Spanning Paxton Creek & Cameron Street (State Route 230) at Mulberry Street (State Route 3012), Harrisburg, Dauphin County, PA

  20. Cement Leakage into Adjacent Vertebral Body Following Percutaneous Vertebroplasty

    PubMed Central

    Park, Jae Hoo; Kim, Hyeun Sung

    2016-01-01

    Percutaneous vertebroplasty (PV) is a minimally invasive procedure for osteoporotic vertebral compression fractures that fail to respond to conventional conservative treatment. It significantly improves intolerable back pain within hours, and has a low complication rate. Although rare, PV is not free of complications, most of which are directly related to cement leakage. Because of its association with new adjacent fracture, the importance of cement leakage into the adjacent disc space is paramount. Here, we report an interesting case of cement leakage into the adjacent upper vertebral body as well as disc space following PV. To the best of our knowledge, there has been no report of cement leakage into the adjacent vertebral body following PV. This rare case is presented along with a review of the literature. PMID:27437018

  1. 1. HEBRONVILLE MILL COMPLEX ADJACENT TO NORTHEAST CORRIDOR. HEBRONVILLE, BRISTOL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. HEBRONVILLE MILL COMPLEX ADJACENT TO NORTHEAST CORRIDOR. HEBRONVILLE, BRISTOL CO., MA. Sec. 4116, MP 193.75. - Northeast Railroad Corridor, Amtrak Route between RI/MA State Line & South Station, Boston, Suffolk County, MA

  2. 3. DODGEVILLE MILL COMPLEX ADJACENT TO NORTHEAST CORRIDOR DODGEVILLE, BRISTOL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. DODGEVILLE MILL COMPLEX ADJACENT TO NORTHEAST CORRIDOR DODGEVILLE, BRISTOL CO., MA. Sec. 4116, MP 195.55. - Northeast Railroad Corridor, Amtrak Route between RI/MA State Line & South Station, Boston, Suffolk County, MA

  3. 33. HISTORIC PLAQUE MARKING WHERE JOHNSTON DIED, ADJACENT TO PATHWAY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    33. HISTORIC PLAQUE MARKING WHERE JOHNSTON DIED, ADJACENT TO PATHWAY WITH CONCRETE CULVERT LEADING NORTH OUT OF RAVINE TOWARD JOHNSTON MEMORIAL SITE. VIEW NW. - Shiloh National Military Park Tour Roads, Shiloh, Hardin County, TN

  4. Lock 4 View east of lock wall and adjacent ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Lock 4 - View east of lock wall and adjacent roadway built atop tow path. The gate pocket can be seen at center. - Savannah & Ogeechee Barge Canal, Between Ogeechee & Savannah Rivers, Savannah, Chatham County, GA

  5. 1. Ninth Street (west) facade. Adjacent on the north is ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Ninth Street (west) facade. Adjacent on the north is the 9th Street facade of 816 E Street. Both buildings were originally one property. - Riley Building, Rendezvous Adult Magazines & Films, 437 Ninth Street, Northwest, Washington, District of Columbia, DC

  6. 2. THREEQUARTER VIEW FROM ADJACENT ACCESS ROAD SHOWING THREE SPANS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. THREE-QUARTER VIEW FROM ADJACENT ACCESS ROAD SHOWING THREE SPANS AND NORTHWEST APPROACH SPANS, LOOKING SOUTHEAST - Red River Bridge, Spanning Red River at U.S. Highway 82, Garland, Miller County, AR

  7. 1. VIEW FROM ROOFTOP OF BUILDING (MOTEL) ADJACENT TO TECHWOOD ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. VIEW FROM ROOFTOP OF BUILDING (MOTEL) ADJACENT TO TECHWOOD HOMES, LOOKING SOUTH. GARAGE TO EXTREME LEFT, BUILDING 1 TO EXTREME RIGHT. - Techwood Homes (Public Housing), Bounded by North Avenue, Parker Street, William Street & Lovejoy Street, Atlanta, Fulton County, GA

  8. 3. View of north side of house facing from adjacent ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. View of north side of house facing from adjacent vacant property. Original wood lap siding and trim is covered by aluminum siding. Recessed side porch is in middle. - 645 South Eighteenth Street (House), Louisville, Jefferson County, KY

  9. 7. August, 1970 9 ORANGE STREET, ADJACENT TO UNITARIAN CHURCH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. August, 1970 9 ORANGE STREET, ADJACENT TO UNITARIAN CHURCH (NOT IN STUDY AREA) - Orange & Union Streets Neighborhood Study, 8-31 Orange Street, 9-21 Union Street & Stone Alley, Nantucket, Nantucket County, MA

  10. OBLIQUE OF SOUTHWEST END AND SOUTHEAST SIDE, WITH ADJACENT FACILITY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    OBLIQUE OF SOUTHWEST END AND SOUTHEAST SIDE, WITH ADJACENT FACILITY 391 IN THE FOREGROUND. - U.S. Naval Base, Pearl Harbor, Joint Intelligence Center, Makalapa Drive in Makalapa Administration Area, Pearl City, Honolulu County, HI

  11. Complications in exodontia--accidental dislodgment to adjacent anatomical areas.

    PubMed

    Grandini, S A; Barros, V M; Salata, L A; Rosa, A L; Soares, U N

    1993-01-01

    The authors report 4 cases of accidental dislodgement of teeth to adjacent anatomical areas during extraction. The causes and their prevention are discussed and solutions for the problem are suggested. PMID:8241759

  12. 6. Detail, vertical guides adjacent to east portal of Tunnel ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Detail, vertical guides adjacent to east portal of Tunnel 28, view to southwest, 135mm lens with electronic flash fill. - Central Pacific Transcontinental Railroad, Tunnel No. 28, Milepost 134.75, Applegate, Placer County, CA

  13. VIEW OF CONSTRUCTION CAMP ROCK FEATURE WITH OVER, ADJACENT TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF CONSTRUCTION CAMP ROCK FEATURE WITH OVER, ADJACENT TO THE COLUMBIA SOUTHERN CANAL. LOOKING NORTHWEST - Tumalo Irrigation District, Tumalo Project, West of Deschutes River, Tumalo, Deschutes County, OR

  14. Pump house adjacent to the superintendent's house at the west ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Pump house adjacent to the superintendent's house at the west end of the complex near Highway 101. Detail of Holloshaft pump. View to the south. - Prairie Creek Fish Hatchery, Hwy. 101, Orick, Humboldt County, CA

  15. VIEW OF NORTHERN AND EASTERN SIDES FROM PARKING LOT ADJACENT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF NORTHERN AND EASTERN SIDES FROM PARKING LOT ADJACENT TO BUILDING 199 (POLICE STATION) - U.S. Naval Base, Pearl Harbor, Post Office, Avenue A near Eleventh Avenue, Pearl City, Honolulu County, HI

  16. 24. INTERIOR VIEW, WILLIAM GRAY AT SIZING GUAGE ADJACENT TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    24. INTERIOR VIEW, WILLIAM GRAY AT SIZING GUAGE ADJACENT TO BRADLEY HAMMER; NOTE THIS IS THE SAME TOOL AS BEING FORGED ABOVE - Warwood Tool Company, Foot of Nineteenth Street, Wheeling, Ohio County, WV

  17. Detail exterior view looking north showing piping system adjacent to ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail exterior view looking north showing piping system adjacent to engine house. Gas cooling system is on far right. - Burnsville Natural Gas Pumping Station, Saratoga Avenue between Little Kanawha River & C&O Railroad line, Burnsville, Braxton County, WV

  18. VIEW OF LAMP FIXTURE (EXTERIOR) ADJACENT TO ENTRANCE AT SOUTHWEST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF LAMP FIXTURE (EXTERIOR) ADJACENT TO ENTRANCE AT SOUTHWEST CORNER OF BUILDING 23, FACING NORTH - Roosevelt Base, Auditorium-Gymnasium, West Virginia Street between Richardson & Reeves Avenues, Long Beach, Los Angeles County, CA

  19. 14. Charles Acey Cobb standing adjacent to the fish screen ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. Charles Acey Cobb standing adjacent to the fish screen he designed and installed in the Congdon Canal, facing southeast. Photo dates ca. late 1920's. - Congdon Canal, Fish Screen, Naches River, Yakima, Yakima County, WA

  20. 52. EASTSIDE PLANT: GENERAL VIEW OF GOVERNOR ADJACENT TO GENERATOR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    52. EASTSIDE PLANT: GENERAL VIEW OF GOVERNOR ADJACENT TO GENERATOR - American Falls Water, Power & Light Company, Island Power Plant, Snake River, below American Falls Dam, American Falls, Power County, ID

  1. Interior building details of Building A, dungeon cell adjacent to ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior building details of Building A, dungeon cell adjacent to northwest cell: granite and brick threshold, poured concrete floors, plastered finished walls, vaulted veiling; northwesterly view - San Quentin State Prison, Building 22, Point San Quentin, San Quentin, Marin County, CA

  2. VIEW OF CONCRETE CHANNEL ADJACENT TO TUMALO FEED CANAL INTAKE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF CONCRETE CHANNEL ADJACENT TO TUMALO FEED CANAL INTAKE STRUCTURE (DOWNSTREAM SIDE). LOOKING EAST/NORTHEAST - Tumalo Irrigation District, Tumalo Project, West of Deschutes River, Tumalo, Deschutes County, OR

  3. Mercury in the marine boundary layer and seawater of the South China Sea: Concentrations, sea/air flux, and implication for land outflow

    NASA Astrophysics Data System (ADS)

    Fu, Xuewu; Feng, Xinbin; Zhang, Gan; Xu, Weihai; Li, Xiangdong; Yao, Hen; Liang, Peng; Li, Jun; Sommar, Jonas; Yin, Runsheng; Liu, Na

    2010-03-01

    Using R/V Shiyan 3 as a sampling platform, measurements of gaseous elemental mercury (GEM), surface seawater total mercury (THg), methyl mercury (MeHg), and dissolved gaseous mercury (DGM) were carried out above and in the South China Sea (SCS). Measurements were collected for 2 weeks (10 to 28 August 2007) during an oceanographic expedition, which circumnavigated the northern SCS from Guangzhou (Canton), Hainan Inland, the Philippines, and back to Guangzhou. GEM concentrations over the northern SCS ranged from 1.04 to 6.75 ng m-3 (mean: 2.62 ng m-3, median: 2.24 ng m-3). The spatial distribution of GEM was characterized by elevated concentrations near the coastal sites adjacent to mainland China and lower concentrations at stations in the open sea. Trajectory analysis revealed that high concentrations of GEM were generally related to air masses from south China and the Indochina peninsula, while lower concentrations of GEM were related to air masses from the open sea area, reflecting great Hg emissions from south China and Indochina peninsula. The mean concentrations of THg, MeHg, and DGM in surface seawater were 1.2 ± 0.3 ng L-1, 0.12 ± 0.05 ng L-1, and 36.5 ± 14.9 pg L-1, respectively. In general, THg and MeHg levels in the northern SCS were higher compared to results reported from most other oceans/seas. Elevated THg levels in the study area were likely attributed to significant Hg delivery from surrounding areas of the SCS primarily via atmospheric deposition and riverine input, whereas other sources like in situ production by various biotic and abiotic processes may be important for MeHg. Average sea/air flux of Hg in the study area was estimated using a gas exchange method (4.5 ± 3.4 ng m-2 h-1). This value was comparable to those from other coastal areas and generally higher than those from open sea environments, which may be attributed to the reemission of Hg previously transported to this area.

  4. Adjacent Segment Disease Perspective and Review of the Literature

    PubMed Central

    Saavedra-Pozo, Fanor M.; Deusdara, Renato A. M.; Benzel, Edward C.

    2014-01-01

    Background Adjacent segment disease has become a common topic in spine surgery circles because of the significant increase in fusion surgery in recent years and the development of motion preservation technologies that theoretically should lead to a decrease in this pathology. The purpose of this review is to organize the evidence available in the current literature on this subject. Methods For this literature review, a search was conducted in PubMed with the following keywords: adjacent segment degeneration and disease. Selection, review, and analysis of the literature were completed according to level of evidence. Results The PubMed search identified 850 articles, from which 41 articles were selected and reviewed. The incidence of adjacent segment disease in the cervical spine is close to 3% without a significant statistical difference between surgical techniques (fusion vs arthroplasty). Authors report the incidence of adjacent segment disease in the lumbar spine to range from 2% to 14%. Damage to the posterior ligamentous complex and sagittal imbalances are important risk factors for both degeneration and disease. Conclusion Insufficient evidence exists at this point to support the idea that total disc arthroplasty is superior to fusion procedures in minimizing the incidence of adjacent segment disease. The etiology is most likely multifactorial but it is becoming abundantly clear that adjacent segment disease is not caused by motion segment fusion alone. Fusion plus the presence of abnormal end-fusion alignment appears to be a major factor in creating end-fusion stresses that result in adjacent segment degeneration and subsequent disease. The data presented cast further doubt on previously established rationales for total disc arthroplasty, at least with regard to the effect of total disc arthroplasty on adjacent segment degeneration pathology. PMID:24688337

  5. Approximating the largest eigenvalue of network adjacency matrices

    NASA Astrophysics Data System (ADS)

    Restrepo, Juan G.; Ott, Edward; Hunt, Brian R.

    2007-11-01

    The largest eigenvalue of the adjacency matrix of a network plays an important role in several network processes (e.g., synchronization of oscillators, percolation on directed networks, and linear stability of equilibria of network coupled systems). In this paper we develop approximations to the largest eigenvalue of adjacency matrices and discuss the relationships between these approximations. Numerical experiments on simulated networks are used to test our results.

  6. Influences of sea ice on eastern Bering Sea phytoplankton

    NASA Astrophysics Data System (ADS)

    Zhou, Qianqian; Wang, Peng; Chen, Changping; Liang, Junrong; Li, Bingqian; Gao, Yahui

    2015-03-01

    The influence of sea ice on the species composition and cell density of phytoplankton was investigated in the eastern Bering Sea in spring 2008. Diatoms, particularly pennate diatoms, dominated the phytoplankton community. The dominant species were Grammonema islandica (Grunow in Van Heurck) Hasle, Fragilariopsis cylindrus (Grunow) Krieger, F. oceanica (Cleve) Hasle, Navicula vanhoeffenii Gran, Thalassiosira antarctica Comber, T. gravida Cleve, T. nordenskiöeldii Cleve, and T. rotula Meunier. Phytoplankton cell densities varied from 0.08×104 to 428.8×104 cells/L, with an average of 30.3×104 cells/L. Using cluster analysis, phytoplankton were grouped into three assemblages defined by ice-forming conditions: open water, ice edge, and sea ice assemblages. In spring, when the sea ice melts, the phytoplankton dispersed from the sea ice to the ice edge and even into open waters. Thus, these phytoplankton in the sea ice may serve as a "seed bank" for phytoplankton population succession in the subarctic ecosystem. Moreover, historical studies combined with these results suggest that the sizes of diatom species have become smaller, shifting from microplankton to nannoplankton-dominated communities.

  7. Particle fluxes and their drivers in the Avilés submarine canyon and adjacent slope, central Cantabrian margin, Bay of Biscay

    NASA Astrophysics Data System (ADS)

    Rumín-Caparrós, A.; Sanchez-Vidal, A.; González-Pola, C.; Lastras, G.; Calafat, A.; Canals, M.

    2016-05-01

    The Avilés Canyon in the central Cantabrian margin is one of the largest submarine canyons in Europe, extending from the shelf edge at 130 m depth to 4765 m depth in the Biscay abyssal plain. In this paper we present the results of a year-round (March 2012 to April 2013) study of particle fluxes in this canyon and the adjacent continental slope. Three mooring lines equipped with automated sequential sediment traps, high-accuracy conductivity-temperature recorders and current meters allowed measuring total mass fluxes and their major components (lithogenics, calcium carbonate, opal and organic matter) in the settling material jointly with a set of environmental parameters. The integrated analysis of the data obtained from the moorings together with remote sensing images and meteorological and hydrographical data has shed light on the sources of particles and the across- and along margin mechanisms involved in their transfer to the deep. Our results allow interpreting the dynamics of the sedimentary particles in the study area. Two factors play a critical role: (i) direct delivery of river-sourced material to the narrow continental shelf, and (ii) major resuspension events caused by large waves and near bottom currents developing at the occasion of the rather frequent severe storms that are typical of the Cantabrian Sea. Wind direction and subsequent wind-driven currents largely determine the way sedimentary particles reach the canyon. While westerly winds favour the injection of sediments into the Avilés Canyon mainly by building an offshore transport in the bottom Ekman layer, easterly winds ease the offshore advection of particulate matter towards the Avilés Canyon and its adjacent western slope principally through the surface Ekman layer. Furthermore, repeated cycles of semidiurnal tides add an extra amount of energy to the prevailing bottom currents and actively contribute to keep a permanent background of suspended particles in near-bottom waters. High

  8. Thermohaline variability in the Adriatic and Northern Ionian Seas observed from the Argo floats during 2010-2014

    NASA Astrophysics Data System (ADS)

    Kovačević, Vedrana; Ursella, Laura; Gačić, Miroslav; Notarstefano, Giulio; Menna, Milena; Bensi, Manuel; Civitarese, Giuseppe; Poulain, Pierre-Marie

    2015-04-01

    The Adriatic Sea is the northernmost basin of the Eastern Mediterranean Sea (EMed). At its southern end, the basin communicates with the adjacent Ionian Sea through the 80 km wide and 850 m deep Strait of Otranto. Due to the river discharge in the north and due to the strong winter cooling, the Adriatic is both a dilution basin and the dense water formation region. The basin-wide circulation is cyclonic. The circulation is however, energetic also at smaller spatial and temporal scales, and several circulation cells and mesoscale features are regularly observed equally along the littoral and in the open sea. The North Adriatic Dense Water (NAdDW) formed during winter is the densest water of the whole Mediterranean Sea (up to 1060 kg/m3). It flows as a density driven bottom current from the northern shelf toward south, filling the deep layers of the middle and southern Adriatic pits. The deep open-sea area of the South Adriatic Pit (SAP, 1200 m) feels the influence of a water mass exchange through the Strait of Otranto. Specifically, it receives salty and warm surface and Levantine Intermediate Waters from the Ionian Sea. Through the open-sea winter convection that homogenizes and ventilates 400-800 m thick upper water column, this salty water contributes to the formation of the Adriatic Deep Water (AdDW, 1029.17-1029.20 kg/m3), which is not as dense as the NAdDW. Both dense waters eventually mix and spill across the sill ventilating the deep and bottom layers of the Ionian Sea, and driving the deep thermohaline cell of the EMed. Thermohaline properties of the Adriatic Sea vary at wide spatial and temporal scales, and this in turn affects the properties of its dense waters. The long-term scales are of a particular interest, as they are often associated with the biogeochemical and biotic variability such as intrusion of alien species into the Adriatic Sea and interconnection with the adjacent Ionian basin. Due to the extremely variable meteo- and climatic conditions

  9. Phytoplankton assemblage of Yangtze River Estuary and the adjacent east China sea in summer, 2004

    NASA Astrophysics Data System (ADS)

    Luan, Qingshan; Sun, Jun; Shen, Zhiliang; Song, Shuqun; Wang, Min

    2006-04-01

    A cruise was conducted from late August to early September 2004 with the intention of obtaining an interdisciplinary understanding of the Yangtze River Estuary including the biological, chemical and physical subjects. Water sample analysis indicated that total phytoplankton species richness was 137. Of them 81 were found in Bacillariophyta and 48 in Pyrrophyta, accounting for 59.1% and 35.0% respectively. The average cell abundance of surface water samples was 8.8×104 cells L-1, with the maximum, 102.9×104 cells L-1, encountered in the area (31.75°N, 122.33°E) and the minimum, 0.2×104 cells L-1, in (30.75°N, 122.17°E). The dominant species at most stations were Skeletonema costatum and Proboscia alata f. gracillima with the dominance of 0.35 and 0.27. Vertical distribution analysis indicated that obvious stratification of cell abundance and dominant species was found in the representative stations of 5, 18 and 33. Shannon-Wiener index and evenness of phytoplankton assemblage presented negative correlation with the cell abundance, with the optimum appearing in (30.75°N, 122.67°E). According to the PCA analysis of the environmental variables, elevated nutrients of nitrate, silicate and phosphate through river discharge were mainly responsible for the phytoplankton bloom in this area.

  10. Phaneorozoic sequence stratigraphy of Bolivia and adjacent regions

    SciTech Connect

    Sempere, T. )

    1993-02-01

    Phaneorozoic sequence stratigraphy of the Pacific margin of western South America, particularly the Bolivian section, has been completed and new interpretations and hypotheses have been proposed as a result of data analyses of this information. The Paleozoic margin was initially passive (late Cambrian-Llanvirn, [open quotes]Puna aulacogen[close quotes]), but became active during a middle Ordovician compressional episode. Most of late Cambrian to early Triassic Bolivian rocks are of marine origin, with dark shale units recording sea level rises, whereas middle Triassic to Recent rocks were mainly deposited in continental environments (except six restricted-marine ingressions in the late Cretaceous-Danian, and one in the late Miocene, all with hydrocarbon potential). A noteworthy similarity exists between the Devonian to Jurassic stratigraphies of Bolivia and the Parana basin, suggesting that Bolivia behaved as part of the Brazilian craton from late Cambrian to late Jurassic, when it was captured into the Pacific margin geotectonic system. Organic-rich units correlate with Paleozoic highstand deposits and younger ingressions. The Bolivian Phanerozoic strata is characterized by thick layers, partly due to middle Ordovician-Carboniferous and late Cretaceous-Cenozoic foreland basins. Paleozoic foreland geometries include northeastern onlaps and, potentially, stratigraphic traps. Hydrocarbon generation, migration and trapping mainly depended on Cenozoic structural loading and burial and on propagation of Andean deformation which are comprised of Paleozoic shale decollements. Precise knowledge of the evolution of the Phanerozoic geodynamic contexts and basin geometries through sedimentation and subsequent deformations is crucial for hydrocarbon exploration strategies in these regions.

  11. Short term changes in zooplankton community during the summer-autumn transition in the open NW Mediterranean Sea: species composition, abundance and diversity

    NASA Astrophysics Data System (ADS)

    Raybaud, V.; Nival, P.; Mousseau, L.; Gubanova, A.; Altukhov, D.; Khvorov, S.; Ibañez, F.; Andersen, V.

    2008-05-01

    Short term changes in zooplankton community were investigated at a fixed station in offshore waters of the Ligurian Sea (Dynaproc 2 cruise, September-October 2004). Mesozooplankton was sampled with vertical WP2 hauls (200 µm mesh-size) and large mesozooplankton, macrozooplankton and micronekton with a BIONESS multinet sampler (500 µm mesh-size). Temporal variations of total biomass, species composition and abundance of major taxa were studied. Intrusions of low salinity water masses were observed two times during the cruise. The first one, which was the most important, was associated with changes in zooplankton community composition. Among copepods, the abundance of Calocalanus, Euchaeta, Heterorhabdus, Mesocalanus, Nannocalanus, Neocalanus, Pleuromamma and also calanoid copepodites increased markedly. Among non-copepod taxa, only small ostracods abundance increased. After this low salinity event, abundance of all taxa nearly returned to their initial values. The influence of salinity on each zooplankton taxon was confirmed by a statistical analysis (Perry's method). Shannon diversity index, Pielou evenness and species richness were used to describe temporal variations of large copepod (>500 µm) diversity. Shannon index and Pielou evenness decreased at the beginning of the low salinity water intrusions, but not species richness. We suggest that low salinity water masses contained its own zooplankton community and passed through the sampling area, thus causing the replacement of zooplankton population.

  12. Short term changes in zooplankton community during the summer-autumn transition in the open NW Mediterranean Sea: species composition, abundance and diversity

    NASA Astrophysics Data System (ADS)

    Raybaud, V.; Nival, P.; Mousseau, L.; Gubanova, A.; Altukhov, D.; Khvorov, S.; Ibañez, F.; Andersen, V.

    2008-12-01

    Short term changes in zooplankton community were investigated at a fixed station in offshore waters of the Ligurian Sea (DYNAPROC 2 cruise, September-October 2004). Mesozooplankton were sampled with vertical WP-II hauls (200 μm mesh-size) and large mesozooplankton, macrozooplankton and micronekton with a BIONESS multinet sampler (500 μm mesh-size). Temporal variations of total biomass, species composition and abundance of major taxa were studied. Intrusions of low salinity water masses were observed two times during the cruise. The first one, which was the most intense, was associated with changes in zooplankton community composition. Among copepods, the abundance of Calocalanus, Euchaeta, Heterorhabdus, Mesocalanus, Nannocalanus, Neocalanus, Pleuromammaand also calanoid copepodites increased markedly. Among non-copepod taxa, only small ostracods abundance increased. After this low salinity event, abundance of all taxa nearly returned to their initial values. The influence of salinity on each zooplankton taxon was confirmed by a statistical analysis (Perry's method). The Shannon diversity index, Pielou evenness and species richness were used to describe temporal variations of large copepod (>500 μm) diversity. The Shannon index and Pielou evenness decreased at the beginning of the low salinity water intrusions, but not species richness. We suggest that low salinity water masses contained its own zooplankton community and passed through the sampling area, thus causing a replacement of the zooplankton population.

  13. SeaMARC II mapping of transform faults in the Cayman Trough, Caribbean Sea

    USGS Publications Warehouse

    Rosencrantz, Eric; Mann, Paul

    1992-01-01

    SeaMARC II maps of the southern wall of the Cayman Trough between Honduras and Jamaica show zones of continuous, well-defined fault lineaments adjacent and parallel to the wall, both to the east and west of the Cayman spreading axis. These lineaments mark the present, active traces of transform faults which intersect the southern end of the spreading axis at a triple junction. The Swan Islands transform fault to the west is dominated by two major lineaments that overlap with right-stepping sense across a large push-up ridge beneath the Swan Islands. The fault zone to the east of the axis, named the Walton fault, is more complex, containing multiple fault strands and a large pull-apart structure. The Walton fault links the spreading axis to Jamaican and Hispaniolan strike-slip faults, and it defines the southern boundary of a microplate composed of the eastern Cayman Trough and western Hispaniola. The presence of this microplate raises questions about the veracity of Caribbean plate velocities based primarily on Cayman Trough opening rates.

  14. Space Radar Image of Weddell Sea, Antarctica

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This Spaceborne Imaging Radar-C/X-band Synthetic Aperture Radar color composite shows a portion of the Weddell Sea, which is adjacent to the continent of Antarctica. The image shows extensive coverage of first-year sea ice mixtures and patches of open water inside the ice margin. The image covers a 100 kilometer by 30 kilometer (62 mile by 18.5 mile) region of the southern ocean, centered at approximately 57 degrees south latitude and 3 degrees east longitude, which was acquired on October 3, 1994. Data used to create this image were obtained using the L-band (horizontally transmitted and vertically received) in red; the L-band (horizontally transmitted and received) in green; and the C-band (horizontally transmitted and received) in blue. The sea ice, which appears rust-brown in the image, is composed of loosely packed floes from approximately 1 meter to 2 meters (3 feet to 6.5 feet) thick and ranging from 1 meter to 20 meters (3 feet to 65.5 feet) in diameter. Large patches of open water, shown as turquoise blue, are scattered throughout the area, which is typical for ice margins experiencing off-ice winds. The thin, well-organized lines clearly visible in the ice pack are caused by radar energy reflected by floes riding the crest of ocean swells. The wispy, black features seen throughout the image represent areas where new ice is forming. Sea ice, because it acts as an insulator, reduces the loss of heat between the relatively warm ocean and cold atmosphere. This interaction is an important component of the global climate system. Because of the unique combination of winds, currents and temperatures found in this region, ice can extend many hundreds of kilometers north of Antarctica each winter, which classifies the Weddell Sea as one of nature's greatest ice-making engines. During the formation of sea ice, great quantities of salt are expelled from the frozen water. The salt increases the density of the upper layer of sea water, which then sinks to great depths

  15. Remote Sensing of Sea Ice in the Northern Sea Route: Studies and Applications

    NASA Astrophysics Data System (ADS)

    Barry, Roger G.

    2008-07-01

    Given the rapid changes that are under way in Arctic sea ice extent, Remote Sensing of Sea Ice in the Northern Sea Route is a timely work. The Northern Sea Route (NSR), along the Arctic coast of Russia, has a long history, dating back to 1932, when the Soviet Union established the NSR administration to develop hydrometeorological services. Shipping along the sea route peaked in the 1980s, but there is renewed interest associated with a lengthening ice-free season and mineral exploitation. Since July 1991, the NSR has been open to all merchant vessels.

  16. The Very Late Eocene Opening of Fram Strait between the Arctic Ocean and the Nordic Seas: Linkages with the Popigai Impact

    NASA Astrophysics Data System (ADS)

    Hillaire-Marcel, C.; Poirier, A.

    2013-12-01

    The transition from the Eocene Arctic Lake to the Arctic Ocean through the opening of Fram Strait, initially dated at ca. 18 Ma based on palynological inferences (Moran et al., 2004, Nature 441, 601-605), has been recently assigned to the very late Eocene (~ 36 Ma) based on Os-isotope stratigraphy and Re-Os isochron ages of sediments from the IODP-ACEX core (Lomonosov Ridge) (Poirier & Hillaire-Marcel, 2011, GRL 38, L14607). Here, we examine the potential linkages of this event with the Popigai meteoritic impact from northeastern Siberia, which has been dated independently at 35.7×0.2 Ma (Bottomley et al. 1997, Nature 338, 365-368). Noteworthy is the fact that in the earliest marine sediments of the ACEX core, the Os-isotope stratigraphy records an isotopic excursion which we tentatively assigned to the chondritic impactor of Popigai. Sr and Pb isotope signatures of detrital sediments (i.e., following the removal of exchangeable fractions) were thus used to further document the sources of terrigenous sediments deposited before, during, and after the transition episode. Above and below the lacustrine/marine boundary, we note relatively constant source provenances (or mixture of sources), implying that relative contributions from regional detrital sedimentary sources, thus relative erosion rates over surrounding continents, did not change much at a Ma-long time scale. On the other hand, a sharp change highlights the lacustrine/marine transition, with an abrupt shift to low values in 87Sr/88Sr, also marked by a (smaller) excursion in all three 204Pb-normalised lead isotopes values (corrected for in-situ decay of U). This isotopic excursion might also be due to the Popigai chondritic Impactor. The impact-related ejection over basaltic target materials would have produced the particulate matter of suitable composition (Wooden et al. 1993, GCA 57, 3677-3704) to account for the isotopic excursion observed. A first order estimate of the Popigai impact yields a value of

  17. Sea Legs

    NASA Astrophysics Data System (ADS)

    Macdonald, Kenneth C.

    Forty-foot, storm-swept seas, Spitzbergen polar bears roaming vast expanses of Arctic ice, furtive exchanges of forbidden manuscripts in Cold War Moscow, the New York city fashion scene, diving in mini-subs to the sea floor hot srings, life with the astronauts, romance and heartbreak, and invading the last bastions of male exclusivity: all are present in this fast-moving, non-fiction account of one woman' fascinating adventures in the world of marine geology and oceanography.

  18. Plasma levels of pollutants are much higher in loggerhead turtle populations from the Adriatic Sea than in those from open waters (Eastern Atlantic Ocean).

    PubMed

    Bucchia, Matteo; Camacho, María; Santos, Marcelo R D; Boada, Luis D; Roncada, Paola; Mateo, Rafael; Ortiz-Santaliestra, Manuel E; Rodríguez-Estival, Jaime; Zumbado, Manuel; Orós, Jorge; Henríquez-Hernández, Luis A; García-Álvarez, Natalia; Luzardo, Octavio P

    2015-08-01

    In this paper we determined the levels of 63 environmental contaminants, including organic (PCBs, organochlorine pesticides, and PAHs) and inorganic (As, Cd, Cu, Pb, Hg and Zn) compounds in the blood of loggerhead turtles (Caretta caretta) from two comparable populations that inhabit distinct geographic areas: the Adriatic Sea (Mediterranean basin) and the Canary Islands (Eastern Atlantic Ocean). All animals were sampled at the end of a period of rehabilitation in centers of wildlife recovery, before being released back into the wild, so they can be considered to be in good health condition. The dual purpose of this paper is to provide reliable data on the current levels of contamination of this species in these geographic areas, and secondly to compare the results of both populations, as it has been reported that marine biota inhabiting the Mediterranean basin is exposed to much higher pollution levels than that which inhabit in other areas of the planet. According to our results it is found that current levels of contamination by organic compounds are considerably higher in Adriatic turtles than in the Atlantic ones (∑PCBs, 28.45 vs. 1.12ng/ml; ∑OCPs, 1.63 vs. 0.19ng/ml; ∑PAHs, 13.39 vs. 4.91ng/ml; p<0.001 in all cases). This is the first time that levels of PAHs are reported in the Adriatic loggerheads. With respect to inorganic contaminants, although the differences were not as great, the Adriatic turtles appear to have higher levels of some of the most toxic elements such as mercury (5.74 vs. 7.59μg/ml, p<0.01). The results of this study confirm that the concentrations are larger in turtles from the Mediterranean, probably related to the high degree of anthropogenic pressure in this basin, and thus they are more likely to suffer adverse effects related to contaminants. PMID:25863507

  19. Poster: the sea urchin.

    PubMed

    2006-11-10

    The announcement of the sequencing of the genome of the sea urchin Strongylocentrotus purpuratus is the latest glowing chapter in the long history of contributions from sea urchin researchers to fundamental principles of cell biology, developmental biology, and gene regulation. A poster created for the print Science presents a timeline of the past and a glimpse into the next stage of research that is being opened up through genomic insights; a PDF of that poster is available for our subscribers. We have also created, for all site visitors, an interactive version of the poster, including additional images, video, and Web resources. Interactive poster (free; requires Flash 8 or higher). PDF of print poster (subscription required). PMID:17095688

  20. The tectonic evolution of the greater South China Sea

    SciTech Connect

    Hayes, D.E. )

    1990-06-01

    The South China Sea (SCS) basin is composed of two major subbasins. The eastern subbasin was formed by seafloor spreading in the middle Tertiary and is associated with roughly E-W-trending magnetic lineations. The southwestern subbasin of the South China Sea is characterized by NE-SW tectonic and magnetic trends and is considerably narrower than the eastern subbasin. There is no obvious structural discontinuity between the two subbasins; hence the initial opening of the eastern subbasin was likely accommodated to the west by a prolonged period of extension of the continental crust that was not accompanied by the formation of normal oceanic crust. The southwest subbasin was eventually also formed by seafloor spreading processes. Although the sequence of magnetic lineations recorded there is relatively short, these data coupled with heatflow and crustal depth data strongly suggest that the southwestern subbasin was not formed until the early-middle Miocene, coincident with the last phase of spreading in the adjacent eastern subbasin. It is still unclear whether or not a significant change in spreading direction occurred within the SCS basin during the early Miocene. The geometry of the deep SCS basin as defined by the seaward limit of the continent-ocean boundary zone provides important constraints on the east-to-west variations in the total crustal extension manifested in the rifted margins of the South China Sea. The amount of new oceanic crust created by seafloor spreading plus the amount of crustal extension accommodated within the continental crust must be nearly the same for all points along the rifted margins. Because the amount of oceanic crust present is quite variable, it follows that the amount of crustal extension must be similarly variable and in a predictable way.

  1. Sea ice terminology

    SciTech Connect

    Not Available

    1980-09-01

    A group of definitions of terms related to sea ice is presented, as well as a graphic representation of late winter ice zonation of the Beaufort Sea Coast. Terms included in the definition list are belt, bergy bit, bight, brash ice, calving, close pack ice, compacting, compact pack ice, concentration, consolidated pack ice, crack, diffuse ice edge, fast ice, fast-ice boundary, fast-ice edge, first-year ice, flaw, flaw lead, floe, flooded ice, fractured, fractured zone, fracturing, glacier, grey ice, grey-white ice, growler, hummock, iceberg, iceberg tongue, ice blink, ice boundary, ice cake, ice edge, ice foot, ice free, ice island, ice shelf, large fracture, lead, medium fracture, multiyear ice, nilas, old ice, open pack ice, open water, pack ice, polar ice, polynya, puddle, rafted ice, rafting, ram, ridge, rotten ice, second-year ice, shearing, shore lead, shore polynya, small fracture, strip, tabular berg, thaw holes, very close pack ice, very open pack ice, water sky, young coastal ice, and young ice.

  2. The Blackwater NWR inundation model. Rising sea level on a low-lying coast: land use planning for wetlands

    USGS Publications Warehouse

    Larsen, Curt; Clark, Inga; Guntenspergen, Glenn; Cahoon, Don; Caruso, Vincent; Hupp, Cliff; Yanosky, Tom

    2004-01-01

    The Blackwater National Wildlife Refuge (BNWR), on the Eastern Shore of Chesapeake Bay (figure 1), occupies an area less than 1 meter above sea level. The Refuge has been featured prominently in studies of the impact of sea level rise on coastal wetlands. Most notably, the refuge has been sited by the Intergovernmental Panel on Climate Change (IPCC) as a key example of 'wetland loss' attributable to rising sea level due to global temperature increase. Comparative studies of aerial photos taken since 1938 show an expanding area of open water in the central area of the refuge. The expanding area of open water can be shown to parallel the record of sea level rise over the past 60 years. The U.S. Fish and Wildlife Service (FWS) manages the refuge to support migratory waterfowl and to preserve endangered upland species. High marsh vegetation is critical to FWS waterfowl management strategies. A broad area once occupied by high marsh has decreased with rising sea level. The FWS needs a planning tool to help predict current and future areas of high marsh available for waterfowl. 'Wetland loss' is a relative term. It is dependant on the boundaries chosen for measurement. Wetland vegetation, zoned by elevation and salinity (figure 3), respond to rising sea level. Wetlands migrate inland and upslope and may vary in areas depending on the adjacent land slopes. Refuge managers need a geospatial tool that allows them to predict future areas that will be converted to high and intertidal marsh. Shifts in location and area of coverage must be anticipated. Viability of a current marsh area is also important. When will sea level rise make short-term management strategies to maintain an area impractical? The USGS has developed an inundation model for the BNWR centered on the refuge and surrounding areas. Such models are simple in concept, but they require a detailed topographic map upon which to superimpose future sea level positions. The new system of LIDAR mapping of land and

  3. Two adjacent inversions maintain genomic differentiation between migratory and stationary ecotypes of Atlantic cod.

    PubMed

    Kirubakaran, Tina Graceline; Grove, Harald; Kent, Matthew P; Sandve, Simen R; Baranski, Matthew; Nome, Torfinn; De Rosa, Maria Cristina; Righino, Benedetta; Johansen, Torild; Otterå, Håkon; Sonesson, Anna; Lien, Sigbjørn; Andersen, Øivind

    2016-05-01

    Atlantic cod is composed of multiple migratory and stationary populations widely distributed in the North Atlantic Ocean. The Northeast Arctic cod (NEAC) population in the Barents Sea undertakes annual spawning migrations to the northern Norwegian coast. Although spawning occurs sympatrically with the stationary Norwegian coastal cod (NCC), phenotypic and genetic differences between NEAC and NCC are maintained. In this study, we resolve the enigma by revealing the mechanisms underlying these differences. Extended linkage disequilibrium (LD) and population divergence were demonstrated in a 17.4-Mb region on linkage group 1 (LG1) based on genotypes of 494 SNPs from 192 parents of farmed families of NEAC, NCC or NEACxNCC crosses. Linkage analyses revealed two adjacent inversions within this region that repress meiotic recombination in NEACxNCC crosses. We identified a NEAC-specific haplotype consisting of 186 SNPs that was fixed in NEAC sampled from the Barents Sea, but segregating under Hardy-Weinberg equilibrium in eight NCC stocks. Comparative genomic analyses determine the NEAC configuration of the inversions to be the derived state and date it to ~1.6-2.0 Mya. The haplotype block harbours 763 genes, including candidates regulating swim bladder pressure, haem synthesis and skeletal muscle organization conferring adaptation to long-distance migrations and vertical movements down to large depths. Our results suggest that the migratory ecotype experiences strong directional selection for the two adjacent inversions on LG1. Despite interbreeding between NEAC and NCC, the inversions are maintaining genetic differentiation, and we hypothesize the co-occurrence of multiple adaptive alleles forming a 'supergene' in the NEAC population. PMID:26923504

  4. Effects of Mackenzie River Discharge and Bathymetry on Sea Ice in the Beaufort Sea

    NASA Technical Reports Server (NTRS)

    Nghiem, S. V.; Hall, D. K.; Rigor, I. G; Li, P.; Neumann, G.

    2014-01-01

    Mackenzie River discharge and bathymetry effects on sea ice in the Beaufort Sea are examined in 2012 when Arctic sea ice extent hit a record low. Satellite-derived sea surface temperature revealed warmer waters closer to river mouths. By 5 July 2012, Mackenzie warm waters occupied most of an open water area about 316,000 sq km. Surface temperature in a common open water area increased by 6.5 C between 14 June and 5 July 2012, before and after the river waters broke through a recurrent landfast ice barrier formed over the shallow seafloor offshore the Mackenzie Delta. In 2012, melting by warm river waters was especially effective when the strong Beaufort Gyre fragmented sea ice into unconsolidated floes. The Mackenzie and other large rivers can transport an enormous amount of heat across immense continental watersheds into the Arctic Ocean, constituting a stark contrast to the Antarctic that has no such rivers to affect sea ice.

  5. Air-sea CO2 fluxes and the controls on ocean surface pCO2 seasonal variability in the coastal and open-ocean southwestern Atlantic Ocean: a modeling study

    NASA Astrophysics Data System (ADS)

    Arruda, R.; Calil, P. H. R.; Bianchi, A. A.; Doney, S. C.; Gruber, N.; Lima, I.; Turi, G.

    2015-10-01

    We use an eddy-resolving, regional ocean biogeochemical model to investigate the main variables and processes responsible for the climatological spatio-temporal variability of pCO2 and the air-sea CO2 fluxes in the southwestern Atlantic Ocean. Overall, the region acts as a sink of atmospheric CO2 south of 30° S, and is close to equilibrium with the atmospheric CO2 to the north. On the shelves, the ocean acts as a weak source of CO2, except for the mid/outer shelves of Patagonia, which act as sinks. In contrast, the inner shelves and the low latitude open ocean of the southwestern Atlantic represent source regions. Observed nearshore-to-offshore and meridional pCO2 gradients are well represented by our simulation. A sensitivity analysis shows the importance of the counteracting effects of temperature and dissolved inorganic carbon (DIC) in controlling the seasonal variability of pCO2. Biological production and solubility are the main processes regulating pCO2, with biological production being particularly important on the shelves. The role of mixing/stratification in modulating DIC, and therefore surface pCO2, is shown in a vertical profile at the location of the Ocean Observatories Initiative (OOI) site in the Argentine Basin (42° S, 42° W).

  6. Laplacian versus adjacency matrix in quantum walk search

    NASA Astrophysics Data System (ADS)

    Wong, Thomas G.; Tarrataca, Luís; Nahimov, Nikolay

    2016-06-01

    A quantum particle evolving by Schrödinger's equation contains, from the kinetic energy of the particle, a term in its Hamiltonian proportional to Laplace's operator. In discrete space, this is replaced by the discrete or graph Laplacian, which gives rise to a continuous-time quantum walk. Besides this natural definition, some quantum walk algorithms instead use the adjacency matrix to effect the walk. While this is equivalent to the Laplacian for regular graphs, it is different for non-regular graphs and is thus an inequivalent quantum walk. We algorithmically explore this distinction by analyzing search on the complete bipartite graph with multiple marked vertices, using both the Laplacian and adjacency matrix. The two walks differ qualitatively and quantitatively in their required jumping rate, runtime, sampling of marked vertices, and in what constitutes a natural initial state. Thus the choice of the Laplacian or adjacency matrix to effect the walk has important algorithmic consequences.

  7. Post-Cromerian rise in sea level

    SciTech Connect

    Olausson, E.

    1992-03-01

    The intensified cooling in the northern hemisphere during the Elsterian-Saalian ice ages (isotopic stages 22-6) resulted in a reduction of the Antarctic ice sheet by 10-15 x 106 km3, equal to a rise in sea level by about 40 m. This rise in sea level changed the hydrography of the Black Sea during the late Pleistocene warmer times, caused anoxic conditions in the eastern Mediterranean during the corresponding warming-up phases, and enhanced water transport of less saline water from the Pacific into the Arctic Ocean (the present sill depth of the Bering Strait is about 50 m). The increased supply of less saline water strengthened the halocline in the Arctic Ocean, increasing the sea ice there and, by higher albedo, its cooling effect on the adjacent continents.

  8. Synopsis of the history of sea otter conservation in the United States

    USGS Publications Warehouse

    Vanblaricom, Glenn R.

    2015-01-01

    In the late 1860s, declining US sea otter populations elicited concern because of prior excessive harvests. Congress mandated protection of Alaskan sea otters in 1868, but hunting continued unrestrained. The Fur Seal Treaty of 1911 (abrogated in 1941) protected sea otters in international waters, but was not applicable to most sea otter habitats and failed to terminate all legal sea otter harvests. Between 1941 and 1972 only the State of California was consistently engaged in sea otter conservation, based on a 1913 state law. Trends in cultural values toward protection of species based on imperiled status rather than economics led to the Marine Mammal Protection Act (1972), giving sea otters unambiguous protection in all US territorial waters. Sea otter habitat protection by the US government began in the 1890s. State marine protected areas potentially support sea otter conservation, particularly when paired with adjacent federal protected entities in or near sea otter habitat.

  9. On the Adjacent Eccentric Distance Sum Index of Graphs

    PubMed Central

    Qu, Hui; Cao, Shujuan

    2015-01-01

    For a given graph G, ε(v) and deg(v) denote the eccentricity and the degree of the vertex v in G, respectively. The adjacent eccentric distance sum index of a graph G is defined as ξsv(G)=∑v∈V(G)ε(v)D(v)deg(v), where D(v)=∑u∈V(G)d(u,v) is the sum of all distances from the vertex v. In this paper we derive some bounds for the adjacent eccentric distance sum index in terms of some graph parameters, such as independence number, covering number, vertex connectivity, chromatic number, diameter and some other graph topological indices. PMID:26091095

  10. Nonlinear spin wave coupling in adjacent magnonic crystals

    NASA Astrophysics Data System (ADS)

    Sadovnikov, A. V.; Beginin, E. N.; Morozova, M. A.; Sharaevskii, Yu. P.; Grishin, S. V.; Sheshukova, S. E.; Nikitov, S. A.

    2016-07-01

    We have experimentally studied the coupling of spin waves in the adjacent magnonic crystals. Space- and time-resolved Brillouin light-scattering spectroscopy is used to demonstrate the frequency and intensity dependent spin-wave energy exchange between the side-coupled magnonic crystals. The experiments and the numerical simulation of spin wave propagation in the coupled periodic structures show that the nonlinear phase shift of spin wave in the adjacent magnonic crystals leads to the nonlinear switching regime at the frequencies near the forbidden magnonic gap. The proposed side-coupled magnonic crystals represent a significant advance towards the all-magnonic signal processing in the integrated magnonic circuits.

  11. Molecular disorganization of axons adjacent to human lacunar infarcts

    PubMed Central

    Lee, Monica D.; Tung, Spencer; Vinters, Harry V.; Carmichael, S. Thomas

    2015-01-01

    Cerebral microvascular disease predominantly affects brain white matter and deep grey matter, resulting in ischaemic damage that ranges from lacunar infarcts to white matter hyperintensities seen on magnetic resonance imaging. These lesions are common and result in both clinical stroke syndromes and accumulate over time, resulting in cognitive deficits and dementia. Magnetic resonance imaging studies suggest that these lesions progress over time, accumulate adjacent to prior lesions and have a penumbral region susceptible to further injury. The pathological correlates of this adjacent injury in surviving myelinated axons have not been previously defined. In this study, we sought to determine the molecular organization of axons in tissue adjacent to lacunar infarcts and in the regions surrounding microinfarcts, by determining critical elements in axonal function: the morphology and length of node of Ranvier segments and adjacent paranodal segments. We examined post-mortem brain tissue from six patients with lacunar infarcts and tissue from two patients with autosomal dominant retinal vasculopathy and cerebral leukoencephalopathy (previously known as hereditary endotheliopathy with retinopathy, nephropathy and stroke) who accumulate progressive white matter ischaemic lesions in the form of lacunar and microinfarcts. In axons adjacent to lacunar infarcts yet extending up to 150% of the infarct diameter away, both nodal and paranodal length increase by ∼20% and 80%, respectively, reflecting a loss of normal cell-cell adhesion and signalling between axons and oligodendrocytes. Using premorbid magnetic resonance images, brain regions from patients with retinal vasculopathy and cerebral leukoencephalopathy that harboured periventricular white matter hyperintensities were selected and the molecular organization of axons was determined within these regions. As in regions adjacent to lacunar infarcts, nodal and paranodal length in white matter of these patients is

  12. INTERIOR OF SOUTH ENTRY AIRLOCK SHOWING STEEL DOORS OPENING TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR OF SOUTH ENTRY AIRLOCK SHOWING STEEL DOORS OPENING TO OUTSIDE AND INTO MAIN EQUIPMENT ROOM, VIEW FACING SOUTHEAST. - Naval Air Station Barbers Point, Telephone Exchange, Coral Sea Road north of Bismarck Sea Road, Ewa, Honolulu County, HI

  13. Inter-annual sea level variability in the southern South China Sea

    NASA Astrophysics Data System (ADS)

    Soumya, M.; Vethamony, P.; Tkalich, P.

    2015-10-01

    The South China Sea (SCS) is the largest marginal sea in the western Pacific Basin. Sea level anomalies (SLAs) in the southern South China Sea (SSCS) are assumed to be governed by various phenomena associated with the adjacent parts of the Indian Ocean and the Pacific Ocean. We have used monthly sea level anomalies obtained from 12 tide gauge stations of PSMSL and UHSLC and merged and gridded AVISO products of SLAs (sea level anomalies) derived from satellite altimeter. We find that IOD-influenced inter-annual variations are found only in the southwestern and southeastern coastal regions of SSCS. Our analysis reveals that inter-annual regional sea level drops are associated with positive phase of the IOD, and the rises with negative phase of the IOD. SLA variations at decadal scale in the southeastern and northern Gulf of Thailand correlate with Pacific Decadal Oscillations (PDO). Multiple linear regression analysis of inter-annual SLAs and climate indices shows that IOD induced inter-annual variations dominate in the southwestern SCS and it contributes to about ~ 40% of inter-annual sea level variation. Meanwhile, ENSO contributes to around ~ 30% variation in sea level in the southwestern and ~ 40% variation in the southeastern SSCS. The present study also suggests that inter-annual SLA variations in the SSCS can occur by ENSO and IOD induced changes in wind stress curl and volume transport variations.

  14. Black Sea

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The Black Sea in eastern Russia is experiencing an ongoing phytoplankton bloom. This image, the most recent in a series that began in early may, shows the waters to be even more colorful than before. part of the increased brightness may be due to the presence of sun glint , especially in the center of the sea. However, more organisms appear to be present as well, their photosynthetic pigments reflecting different wavelengths of light.This Moderate Resolution Imaging Spectroradiometer (MODIS) image was captured on June 15, 2002.

  15. Sea Ice

    NASA Technical Reports Server (NTRS)

    Perovich, D.; Gerland, S.; Hendricks, S.; Meier, Walter N.; Nicolaus, M.; Richter-Menge, J.; Tschudi, M.

    2013-01-01

    During 2013, Arctic sea ice extent remained well below normal, but the September 2013 minimum extent was substantially higher than the record-breaking minimum in 2012. Nonetheless, the minimum was still much lower than normal and the long-term trend Arctic September extent is -13.7 per decade relative to the 1981-2010 average. The less extreme conditions this year compared to 2012 were due to cooler temperatures and wind patterns that favored retention of ice through the summer. Sea ice thickness and volume remained near record-low levels, though indications are of slightly thicker ice compared to the record low of 2012.

  16. Aral Sea

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This series of MODIS images shows the dwindling Aral Sea. Once one of the world's largest freshwater lakes, the Aral Sea has decreased by as much as 60% over the past few decades due to diversion of the water to grow cotton and rice. These diversion have dropped the lake levels, increased salinity, and nearly decimated the fishing industry. The previous extent of the lake is clearly visible as a whitish perimeter in these image from April 16, May 18, and June 3, 2002. s. Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  17. 7. VIEW OF WATER TREATMENT PLANT, ADJACENT TO THE COAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. VIEW OF WATER TREATMENT PLANT, ADJACENT TO THE COAL CONVEYOR; IN THE DISTANCE IS THE FREQUENCY CHANGER HOUSE, WHICH IS ATTACHED TO SWITCH HOUSE NO. 1; LOOKING WEST. - Commonwealth Electric Company, Fisk Street Electrical Generating Station, 1111 West Cermak Avenue, Chicago, Cook County, IL

  18. Colposcopy of vaginal and vulvar human papillomavirus and adjacent sites.

    PubMed

    Hatch, K

    1993-03-01

    Human papillomaviral infections can affect the entire lower female genital tract as multifocal or multicentric disease as well as the surrounding anatomic and adjacent sites. The traditional colposcopic methods are necessary to assist in the diagnosis and help differentiate these infections from other disease mimics. PMID:8392676

  19. Biogeochemistry of hydrothermally and adjacent non-altered soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As a field/lab project, students in the Soil Biogeochemistry class of the University of Nevada, Reno described and characterized seven pedons, developed in hydrothermally and adjacent non-hydrothermally altered andesitic parent material near Reno, NV. Hydrothermally altered soils had considerably lo...

  20. 22. Float located adjacent to entry stair in filtration bed. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    22. Float located adjacent to entry stair in filtration bed. The float actuates a valve that maintains water level over the bed. - Lake Whitney Water Filtration Plant, Filtration Plant, South side of Armory Street between Edgehill Road & Whitney Avenue, Hamden, New Haven County, CT

  1. 2. VIEW FROM ROOFTOP OF BUILDING (MOTEL) ADJACENT TO TECHWOOD ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. VIEW FROM ROOFTOP OF BUILDING (MOTEL) ADJACENT TO TECHWOOD HOMES, LOOKING WEST. GEORGIA TECH DORMITORY BUILDING, 581-587 TECHWOOD DRIVE, IN FOREGROUND. - Techwood Homes (Public Housing), Bounded by North Avenue, Parker Street, William Street & Lovejoy Street, Atlanta, Fulton County, GA

  2. 10. Detail and contextual view of bridge and adjacent farmstead ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. Detail and contextual view of bridge and adjacent farmstead setting. Note laced vertical compression members, latticed portal strut, decorative strut bracing, and lightness of diagonal and lateral tension members. View to southeast through southeast portal from truss mid-span. - Red Bank Creek Bridge, Spanning Red Bank Creek at Rawson Road, Red Bluff, Tehama County, CA

  3. LEHR NO. 2 AND LEHR NO. 3 ADJACENT TO FURNACE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    LEHR NO. 2 AND LEHR NO. 3 ADJACENT TO FURNACE ROOM; THE PIPES AT THE BOTTOM ARE PART OF THE RADIANT HEATING SYSTEM USED FOR HEATING THE FACTORY DURING COLD WEATHER. - Westmoreland Glass Company, Seventh & Kier Streets, Grapeville, Westmoreland County, PA

  4. Effects on stink bugs of field edges adjacent to woodland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Producers face significant crop losses from stink bug species in the southeastern USA, but the high mobility and polyphagy of the bugs make predictions of their presence in crops difficult. While there is some evidence that they colonize crops from adjacent crops, there are no studies of their colo...

  5. VIEW FROM ATOP ADJACENT RESIDENTIAL TOWER, SHOWING INTERSECTION OF ACACIA ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW FROM ATOP ADJACENT RESIDENTIAL TOWER, SHOWING INTERSECTION OF ACACIA ROAD WITH BIRCH CIRCLE. VIEW FACING NORTHEAST - Camp H.M. Smith and Navy Public Works Center Manana Title VII (Capehart) Housing, Intersection of Acacia Road and Brich Circle, Pearl City, Honolulu County, HI

  6. VIEW FROM ATOP ADJACENT RESIDENTIAL TOWER, SHOWING RECREATION AREA AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW FROM ATOP ADJACENT RESIDENTIAL TOWER, SHOWING RECREATION AREA AND ENTRY TO NEIGHBORHOOD. VIEW FACING SOUTHEAST - Camp H.M. Smith and Navy Public Works Center Manana Title VII (Capehart) Housing, Intersection of Acacia Road and Brich Circle, Pearl City, Honolulu County, HI

  7. VIEW FROM ATOP ADJACENT RESIDENTIAL TOWER, SHOWING WESTERN SIDE OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW FROM ATOP ADJACENT RESIDENTIAL TOWER, SHOWING WESTERN SIDE OF NEIGHBORHOOD. VIEW FACING NORTHWEST - Camp H.M. Smith and Navy Public Works Center Manana Title VII (Capehart) Housing, Intersection of Acacia Road and Brich Circle, Pearl City, Honolulu County, HI

  8. VIEW FROM ATOP ADJACENT RESIDENTIAL TOWER, SHOWING RECREATION AREA ON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW FROM ATOP ADJACENT RESIDENTIAL TOWER, SHOWING RECREATION AREA ON RIGHT, AND HOUSING AREA ON LEFT. VIEW FACING EAST/NORTHEAST - Camp H.M. Smith and Navy Public Works Center Manana Title VII (Capehart) Housing, Intersection of Acacia Road and Brich Circle, Pearl City, Honolulu County, HI

  9. How subaerial salt extrusions influence water quality in adjacent aquifers

    NASA Astrophysics Data System (ADS)

    Mehdizadeh, Razieh; Zarei, Mehdi; Raeisi, Ezzat

    2015-12-01

    Brines supplied from salt extrusions cause significant groundwater salinization in arid and semi-arid regions where salt rock is exposed to dissolution by episodic rainfalls. Here we focus on 62 of the 122 diapirs of Hormuz salt emergent in the southern Iran. To consider managing the degradation effect that salt extrusions have on the quality of adjoining aquifers, it is first necessary to understand how they influence adjacent water resources. We evaluate here the impacts that these diapirs have on adjacent aquifers based on investigating their geomorphologies, geologies, hydrologies and hydrogeologies. The results indicate that 28/62 (45%) of our sample of salt diapirs have no significant impact on the quality of groundwater in adjoining aquifers (namely Type N), while the remaining 34/62 (55%) degrade nearby groundwater quality. We offer simple conceptual models that account for how brines flowing from each of these types of salt extrusions contaminate adjacent aquifers. We identify three main mechanisms that lead to contamination: surface impact (Type A), subsurface intrusion (Type B) and indirect infiltration (Type C). A combination of all these mechanisms degrades the water quality in nearby aquifers in 19/62 (31%) of the salt diapirs studied. Having characterized the mechanism(s) by which each diapir affects the adjacent aquifer, we suggest a few possible remediation strategies to be considered. For instance, engineering the surface runoff of diapirs Types A and C into nearby evaporation basins would improve groundwater quality.

  10. 45. 1915 CLOTH ROOM ADJACENT TO PICKER ROOM, SECOND FLOOR, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    45. 1915 CLOTH ROOM ADJACENT TO PICKER ROOM, SECOND FLOOR, NORTH END OF MILL NO. 2, WALL ON LEFT DIVIDING CLOTH ROOM ADDED LATER (PROBABLY C. 1970s). - Prattville Manufacturing Company, Number One, 242 South Court Street, Prattville, Autauga County, AL

  11. Detail of north intermediate abutment pylon showing proximity of adjacent ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail of north intermediate abutment pylon showing proximity of adjacent 1001-1007 East First Street (James K. Hill and Sons Pickle Works Building), facing east - First Street Bridge, Spanning Los Angeles River at First Street, Los Angeles, Los Angeles County, CA

  12. 8. Exterior view, showing tank and associated piping adjacent to ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Exterior view, showing tank and associated piping adjacent to Test Cell 6, Systems Integration Laboratory Building (T-28), looking south. - Air Force Plant PJKS, Systems Integration Laboratory, Systems Integration Laboratory Building, Waterton Canyon Road & Colorado Highway 121, Lakewood, Jefferson County, CO

  13. 4. REAR ELEVATION, DETAIL OF CONSTRUCTION, ADJACENT CORNER POSTS BETWEEN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. REAR ELEVATION, DETAIL OF CONSTRUCTION, ADJACENT CORNER POSTS BETWEEN BUILDING PERIODS 1 AND 3. NOTE REUSED WOOD STRIP NAILED TO BUILDING PERIOD 1 POST INSCRIBED 'ST. LEONARD'. THERE ARE NO NAIL HOLES IN THE PERIOD 3 POST, THE FARRING STRIPS ADJUST FOR CLADDING - Charles' Gift, State Routes 2 & 4, Lusby, Calvert County, MD

  14. 1. OVERVIEW SHOWING FIRING CONTROL BLOCKHOUSE 0502 AND ADJACENT OBSERVATION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. OVERVIEW SHOWING FIRING CONTROL BLOCKHOUSE 0502 AND ADJACENT OBSERVATION TOWER. WATER BRAKE TROUGH SEGMENT AT LOWER RIGHT. Looking north northeast. - Edwards Air Force Base, South Base Sled Track, Firing & Control Blockhouse for 10,000-foot Track, South of Sled Track at midpoint of 20,000-foot track, Lancaster, Los Angeles County, CA

  15. 4. Elevation looking southwest from adjacent hills on northeast side ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Elevation looking southwest from adjacent hills on northeast side of bridge, taken from river level. Note entire east side and substructure. - Presumpscot Falls Bridge, Spanning Presumptscot River at Allen Avenue extension, 0.75 mile west of U.S. Interstate 95, Falmouth, Cumberland County, ME

  16. 49 CFR 236.404 - Signals at adjacent control points.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Signals at adjacent control points. 236.404 Section 236.404 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RULES, STANDARDS, AND INSTRUCTIONS GOVERNING THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR...

  17. 12. LOG FOUNDATION ELEMENTS OF THE SAWMILL ADJACENT TO THE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. LOG FOUNDATION ELEMENTS OF THE SAWMILL ADJACENT TO THE CANAL, LOOKING EAST. BARREN AREA IN FOREGROUND IS DECOMPOSING SAWDUST. DIRT PILE IN BACKGROUND IS THE EDGE OF THE SUMMIT COUNTY LANDFILL. - Snake River Ditch, Headgate on north bank of Snake River, Dillon, Summit County, CO

  18. Spatio-temporal distribution of dissolved sulfide in China marginal seas

    NASA Astrophysics Data System (ADS)

    Wu, Xiaodan; Wu, Bin; Song, Jinming; Li, Xuegang

    2014-09-01

    With sulfide increasingly recognized as an important parameter to assess the oxidation-reduction level in aqueous environment, research on its geochemical behavior is becoming important. Water samples collected in Bohai Sea (1-19 August, 2010), Yellow Sea (20-30 November, 2010) and East China Sea (3-17 June, 2010 and 1-10 November, 2010) were used to determine the occurrence and distribution of dissolved sulfide by methylene blue spectrophotometric method. Results show that: (1) horizontally, concentration of dissolved sulfide significantly varied from the coastal region to the open sea and profoundly influenced by physical processes. High values occurred in the river-sea boundary zone "marginal filter" due to rich riverine input, frequent upwelling and active exchange in shelf edge. Terrestrial input from adjacent rivers and the current cycling contributed to the high sulfide appeared in western Bohai Sea, eastern Shandong Peninsula, and northeast of Changjiang (Yangtze) River estuary. Especially, relative higher sulfide values occurred in Yellow Sea, which is consistent with the variation of salinity largely due to the hydrodynamic feature; (2) vertically, measurement of dissolved sulfide in bottom water was higher and more variable than that in surface water caused by the wind-induced resuspension and dissimilatory sulfate reduction. Moreover, nutrient-type profile clearly identified that oxidation plays a major role in the biogeochemistry cycle of sulfide in water; (3) seasonally, investigation for East China Sea in June and November reflected seasonal variation of Changjiang River Diluted Water, Kuroshio Current, and Taiwan Warm Current. Concentration in June was much higher than that sampled in November at most stations. Mean concentration of dissolved sulfide varied seasonally from 2.26 μg/L (June) to 1.16 μg/L (November) in surface and 3.00 μg/L (June) to 1.56 μg/L (November) in bottom. Progress in the field is slow and more effort is needed to ensure

  19. Ross Sea

    Atmospheric Science Data Center

    2013-04-16

    article title:  Icebergs in the Ross Sea     View Larger Image Two large icebergs, designated B-15A and C-16, are captured in this Multi-angle Imaging ... the longitudinal quadrant in which it is first seen, and new icebergs sighted in that quadrant are sequentially numbered. B-15 divided from ...

  20. Distribution patterns of phytoplankton in the Changjiang River estuary and adjacent waters in spring 2009

    NASA Astrophysics Data System (ADS)

    Kong, Fanzhou; Xu, Zijun; Yu, Rencheng; Yuan, Yongquan; Zhou, Mingjiang

    2016-09-01

    The Changjiang River estuary and adjacent waters are one of the most notable regions for red tides/harmful algal blooms in China's coastal waters. In this study, phytoplankton samples were collected and analyzed during the outbreak stage of red tides in May 2009. It was found that dinoflagellates, Prorocentrum donghaiense and Karenia mikimotoi, and diatoms, Skeletonema spp. and Paralia sulcata, were the major taxa dominating the phytoplankton community. Cluster analysis, non-metric multidimensional scaling (NMDS) and analysis of similarities (ANOSIM) was conducted on a data matrix including taxa composition and cell abundance of the phytoplankton samples. The analyses categorized the samples into three groups at a similarity level of 30%. Group I was characterized by estuarine diatoms and distributed mainly in the highly turbid estuarine region. Group II, which was dominated by the diatom Skeletonema spp. and represented the red tide of Skeletonema spp., was situated around Group I in the sea area west of 122°50'E. Group III was characterized by a high proportion of dinoflagellates and was found further offshore compared with Groups I and II. Group III was further divided into two subgroups (III-S1 and III-S2) at a similarity level of 40%. Group III-S1 was characterized by the presence of the benthic diatom P. sulcata, representing phytoplankton samples collected either from the bottom or from the sea area affected by upwelling. Group III-S2 was dominated by dinoflagellates and represented red tides formed by P. donghaiense and K. mikimotoi. A gradual change of red-tide causative species was observed from the estuary to the offshore sea area, from diatoms to armored dinoflagellates and then unarmored dinoflagellates. Environmental factors associated with each group, and thus affecting the distribution of phytoplankton and red tides, are discussed.

  1. Distribution patterns of phytoplankton in the Changjiang River estuary and adjacent waters in spring 2009

    NASA Astrophysics Data System (ADS)

    Kong, Fanzhou; Xu, Zijun; Yu, Rencheng; Yuan, Yongquan; Zhou, Mingjiang

    2016-01-01

    The Changjiang River estuary and adjacent waters are one of the most notable regions for red tides/harmful algal blooms in China's coastal waters. In this study, phytoplankton samples were collected and analyzed during the outbreak stage of red tides in May 2009. It was found that dinoflagellates, Prorocentrum donghaiense and Karenia mikimotoi, and diatoms, Skeletonema spp. and Paralia sulcata, were the major taxa dominating the phytoplankton community. Cluster analysis, non-metric multidimensional scaling (NMDS) and analysis of similarities (ANOSIM) was conducted on a data matrix including taxa composition and cell abundance of the phytoplankton samples. The analyses categorized the samples into three groups at a similarity level of 30%. Group I was characterized by estuarine diatoms and distributed mainly in the highly turbid estuarine region. Group II, which was dominated by the diatom Skeletonema spp. and represented the red tide of Skeletonema spp., was situated around Group I in the sea area west of 122°50'E. Group III was characterized by a high proportion of dinoflagellates and was found further offshore compared with Groups I and II. Group III was further divided into two subgroups (III-S1 and III-S2) at a similarity level of 40%. Group III-S1 was characterized by the presence of the benthic diatom P. sulcata, representing phytoplankton samples collected either from the bottom or from the sea area affected by upwelling. Group III-S2 was dominated by dinoflagellates and represented red tides formed by P. donghaiense and K. mikimotoi. A gradual change of red-tide causative species was observed from the estuary to the offshore sea area, from diatoms to armored dinoflagellates and then unarmored dinoflagellates. Environmental factors associated with each group, and thus affecting the distribution of phytoplankton and red tides, are discussed.

  2. Gray whale sightings in the Canadian Beaufort Sea, September 2014

    NASA Astrophysics Data System (ADS)

    Iwahara, Yuka; Fujiwara, Amane; Ito, Keizo; Miyashita, Kazushi; Mitani, Yoko

    2016-06-01

    Gray whales (Eschrichtius robustus) are distributed within the productive neritic and estuarine waters of the North Pacific Ocean, the Bering Sea, and adjacent waters of the Arctic Ocean. They migrate to high-latitude feeding grounds each spring. Their main feeding grounds in the Arctic include the Chirikov Basin, the northeastern Chukchi Sea from Pt. Hope to Cape Lisburne and Pt. Lay to Pt. Barrow, and the northwestern Chukchi Sea along the Chukotka coast. Although sightings are rare in the Canadian Beaufort Sea, we observed three gray whales in two groups in this area in September 2014. A mud plume was observed near one of the whales, suggesting the animal had been feeding. In the Alaskan Beaufort Sea, large-scale monitoring of the distributions of marine mammals has been continuously conducted since 1979; however, there has been less monitoring in the Canadian Beaufort Sea. Therefore, it is necessary to record opportunistic sightings, such as those described here.

  3. Creating Arctic Sea Ice Protected Areas?

    NASA Astrophysics Data System (ADS)

    Pfirman, S.; Hoff, K.; Temblay, B.; Fowler, C.

    2008-12-01

    As Arctic sea ice retreats and the Northwest Passage and Northern Sea Route open, the Arctic will experience more extensive human activity than it has ever encountered before. New development will put pressure on a system already struggling to adapt to a changing environment. In this analysis, locations are identified within the Arctic that could be protected from resource extraction, transportation and other development in order to create refuges and protect remnants of sea ice habitat, as the Arctic transitions to ice-free summer conditions. Arctic sea ice forms largely along the Siberian and Alaskan coasts and is advected across the North Pole towards Fram Strait, the Canadian Archipelago and the Barents Sea. In addition to the future loss of ice itself, contaminants entrained in sea ice in one part of the ocean can affect other regions as the ice drifts. Using observations and models of sea ice origins, trajectories and ages, we track sea ice from its origins towards marginal ice zones, mapping pathways and termination locations. Critical sea ice source areas and collection regions are identified with the goal of aiding in the protection of the remaining Arctic sea ice habitat for as long as possible.

  4. Suspended sediment dynamics during the inter-monsoon season in the subaqueous Mekong Delta and adjacent shelf, southern Vietnam

    NASA Astrophysics Data System (ADS)

    Unverricht, Daniel; Nguyen, Thanh Cong; Heinrich, Christoph; Szczuciński, Witold; Lahajnar, Niko; Stattegger, Karl

    2014-01-01

    tidal current velocities. High tidal current velocities of up to 0.6 m/s near the sea bottom generate increasing SSCs of more than 25 μl/l in the water column. Additionally a significant trend of decreasing SSC from the near-seabed to the upper part of the water column can be observed. In terms of sediment transport the ebb phase dominates the tidal cycle by its higher tidal current velocities but the flood phase has the longer duration. The switch of the tidal current direction from ebb to flood phase occurs rapidly against which the change from flood to ebb phase requires up to 3 h. This leads to an asymmetry of the tidal ellipses and may cause a net-sediment transport from the shelf into the subaqueous Mekong Delta.In the subaqueous Mekong Delta and adjacent shelf, seven transects show similar patterns of SSCs dependent to the tidal phase. A hypopycnal sediment plume from the subaqueous Mekong Delta into the shelf region was not observed. Our results imply that resuspension by tidal currents dominates the sediment transport in the subaqueous Mekong Delta and adjacent shelf regions during the inter-monsoon season.

  5. 75 FR 22073 - Fisheries of the Northeastern United States; Atlantic Sea Scallop Fishery; Framework Adjustment 21

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-27

    ... scallop fishery: Total allowable catch (TAC); open area days-at-sea (DAS) and Sea Scallop Access Area... components: Open area DAS; individual access area trips for limited access vessels; IFQ allocations.... Open Area DAS Allocations This action would implement the following vessel-specific DAS allocations...

  6. Circummandibular Wires for Treatment of Dentoalveolar Fractures Adjacent to Edentulous Areas: A Report of Two Cases.

    PubMed

    Maloney, Karl

    2015-09-01

    In general, dentoalveolar fractures are a common injury seen in emergency departments, dental offices, and oral and maxillofacial surgery practices. These injuries can be the result of direct trauma or indirect trauma. Direct trauma more often causes trauma to the maxillary dentition due to the exposure of the maxillary anterior teeth. Indirect trauma is usually the result of forced occlusion secondary to a blow to the chin or from a whiplash injury. Falls are the most common mechanism of injury seen in the pediatric group. In adolescents, many of these fractures are sustained during sporting activities. However, the use of mouth guards and other protective equipment has decreased this number. Most adult injuries are caused by motor vehicle accidents, contact sports, falls, bicycles, interpersonal violence, medical/dental mishaps, and industrial accidents. Early intervention to reduce and stabilize the fracture is required to establish a bony union and ensure correct function. Most dentoalveolar fractures have bilateral stable adjacent dentition and are treated with a closed technique utilizing an acid-etch/resin splint followed by splint removal at 4 weeks. Other inferior stabilization treatments used are arch bars and other wiring techniques. It is widely accepted that semirigid stabilization techniques, such as an acid-etch/resin splint or wiring procedures, are adequate to treat dentoalveolar fractures. This is in contrast to the treatment of mandible fractures where AO principles of rigid fixation are often followed. Fractures that are unable to be reduced sometimes necessitate an open reduction followed by internal fixation, sometimes using a secondary splint for mobile teeth. In those rare cases when there are not stable adjacent teeth bilaterally other modalities must be considered. In the present report, two cases are presented where circummandibular wires were used to treat fractured mandibular dentoalveolar segments adjacent to edentulous areas. PMID

  7. Malaria Vectors in Lake Victoria and Adjacent Habitats in Western Kenya

    PubMed Central

    Minakawa, Noboru; Dida, Gabriel O.; Sonye, George O.; Futami, Kyoko; Njenga, Sammy M.

    2012-01-01

    The prevalence of malaria among the residents of the Lake Victoria basin remains high. The environment associated with the lake may maintain a high number of malaria vectors. Lake habitats including water hyacinths have been suspected to be the source of vectors. This study investigated whether malaria vectors breed in the lake habitats and adjacent backwater pools. Anopheline larvae were collected within the littoral zone of the lake and adjacent pools located along approximately 24.3 km of the lakeshore in western Kenya, and their breeding sites characterized. Three primary vector species, Anopheles arabiensis, Anopheles gambiae s.s. and Anopheles funestus s.s., and three potential vectors, were found in the lake habitats. Unexpectedly, An. arabiensis was the most dominant vector species in the lake sampling sites. Its habitats were uncovered or covered with short grass. A potential secondary malaria vector, Anopheles rivulorum, dominated the water hyacinths in the lake. Most breeding sites in the lake were limited to areas that were surrounded by tall emergent plants, including trees, and those not exposed to waves. Nearly half of adjacent habitats were lagoons that were separated from the lake by sand bars. Lagoons contained a variety of microhabitats. Anopheles arabiensis dominated open habitats, whereas An. funestus s.s. was found mainly in vegetated habitats in lagoons. The current study confirmed that several breeding sites are associated with Lake Victoria. Given that Lake Victoria is the second largest lake in the world, the lake related habitats must be extensive; therefore, making targeted vector control difficult. Further exploration is necessary to estimate the effects of lake associated habitats on malaria transmission so as to inform a rational decision-making process for vector control. PMID:22412913

  8. Cenozoic stratigraphic evolution, North Sea and Labrador Sea

    SciTech Connect

    Gradstein, F.M.; Grant, A.C.; Mudford, B.S. ); Berggren, W.A. ); Kaminski, M.A. ); D'Lorio, M.A. ); Cloetingh, S. ); Griffiths, C.M. )

    1990-05-01

    The authors are studying Cenozoic correlation patterns, burial trends, and subsidence history of the Central North Sea, Labrador, and Orphan basins. The authors objectives are (1) to detail intraregional mid-high latitude biozonations using noise filtering and probabilistic zonation techniques; (2) to detail paleobathymetric trends from basin margins to centers; (3) to apply this knowledge to model basin evolution, in the perspective of the evolving North Atlantic Ocean; (4) to evaluate causes for the occurrence of major hiatuses and rapid changes of subsidence; and (5) to relate rapid changes in sedimentation in the last few millions of years to model observed undercompaction trends. Cenozoic microfossil assemblages in these basins are similar, related to similarities in sedimentary and paleoeceanographic conditions. In more basinal wells, flysch-type agglutinated foraminiferal assemblages occur, also known from Carpathians, Trinidad, and Moroccan foredeeps. Over 90% of agglutinated taxa are common between these basins, although local stratigraphic ranges vary sufficiently to rely on the concept of average ranges, rather than total ones for correlations. Cenozoic stratigraphic resolution in the North Sea and Labrador basins generally is in 3-5-Ma units. and paleobathymetric zonations define a minimum of five niches, from inner shelf to middle slope regimes. Significant hiatuses occurred in the late Eocene through the Miocene, particularly in northern Labrador and northern North Sea. Subsidence in the Labrador/Grand Banks passive margin half grabens was strongly influenced by Labrador Sea opening between anomalies 34 (Campanian) and 13 (early Oligocene), when subsidence exceeded sedimentation and bathyal conditions prevailed along the margin. Thermally induced subsidence in the central North Sea grabens was considerable in the late Paleocene, when the Norwegian Sea started to open.

  9. 38. VIEW OF COTTRELL MAGNETIC IMPULSE GENERATOR ADJACENT TO SIX ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    38. VIEW OF COTTRELL MAGNETIC IMPULSE GENERATOR ADJACENT TO SIX GAP ROTARY RECTIFIER. THIS UNIT GENERATED A MAGNETIC PULSE WHICH WAS TRANSMITTED TO THE COLLECTION PLATES IN THE ELECTROSTATIC PRECIPITATOR CHAMBER. THESE PERIODIC PULSES VIBRATE THE PLATES AND CAUSE PRECIPITATED ARTICLES OF SMOKE AND FLY ASH TO FALL TO THE BOTTOM OF THE PRECIPITATOR CHAMBER. - New York, New Haven & Hartford Railroad, Cos Cob Power Plant, Sound Shore Drive, Greenwich, Fairfield County, CT

  10. Conference room 211, adjacent to commander's quarters, with vault door ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Conference room 211, adjacent to commander's quarters, with vault door at right. Projection area at center is equipped with automatic security drapes. Projection room uses a 45 degree mirror to reflect the image onto the frosted glass screen. Door on far left leads to display area senior battle staff viewing bridge, and the commander's quarters - March Air Force Base, Strategic Air Command, Combat Operations Center, 5220 Riverside Drive, Moreno Valley, Riverside County, CA

  11. Epithelial dysplasia immediately adjacent to oral squamous cell carcinomas.

    PubMed

    Wright, A; Shear, M

    1985-08-01

    A number of workers have attempted to identify dysplastic features which may be predictors of malignant change, by prospective studies of dysplastic lesions. In the present study we have looked at dysplastic changes immediately adjacent to established squamous carcinomas in an attempt to determine whether any predictors can be identified in this way. Eighty cases were included in the study for whom information on tobacco usage was known. Clinical details were recorded. Histological features in epithelium immediately adjacent to the carcinoma were studied in representative sections. Eighteen specific histological characteristics were noted as present or absent. Data were transferred by Conversational Monitoring System (CMS) terminal, processed and analyzed by the Statistical Analysis System (SAS) Computer package. Only 8 patients were non-smokers (10%). Dysplastic changes in adjacent epithelium were frequently multicentric. Changes appear to occur first in the basal layer in the form of disturbance of polarity or basal cell hyperplasia, while other dysplastic features are absent. The feature referred to as basal cell hyperplasia appears, in fact, to represent disturbed epithelial maturation. In 80% of cases increased nucleo-cytoplasmic ratio appears to result from a decrease in cytoplasmic volume rather than increased nuclear size. A defect in RNA synthesis may be a factor. A sharp decrease in inflammatory cells in the lamina propria of adjacent epithelium, compared with that of the carcinoma, was observed. Russell bodies were noted in 5 of the 8 lesions in non-smokers (63%) and in 16 of 72 lesions in smokers (22%) (p less than 0.001; Chi2 17.65). PMID:3928850

  12. 20. Interior view of fuel storage pit or vault adjacent ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    20. Interior view of fuel storage pit or vault adjacent to Test Cell 9 in Component Test Laboratory (T-27), looking west. Photograph shows upgraded instrumentation, piping, tanks, and technological modifications installed in 1997-99 to accommodate component testing requirements for the Atlas V missile. - Air Force Plant PJKS, Systems Integration Laboratory, Components Test Laboratory, Waterton Canyon Road & Colorado Highway 121, Lakewood, Jefferson County, CO

  13. FMRI evidence of acupoints specificity in two adjacent acupoints.

    PubMed

    Liu, Hua; Xu, Jian-Yang; Li, Lin; Shan, Bao-Ci; Nie, Bin-Bin; Xue, Jing-Quan

    2013-01-01

    Objectives. Acupoint specificity is the foundation of acupuncture treatment. The aim of this study is to investigate whether the acupoint specificity exists in two adjacent acupoints. Design and Setting. Two adjacent real acupoints, LR3 (Taichong) and ST44 (Neiting), and a nearby nonacupoint were selected. Thirty-three health volunteers were divided into three groups in random order, and each group only received acupuncture at one of the three points. While they received acupuncture, fMRI scan was performed. Results. The common cerebral activated areas responding to LR3 and ST44 included the contralateral primary somatosensory area (SI) and ipsilateral cerebellum. Acupuncture at LR3 specifically activated contralateral middle occipital gyrus, ipsilateral medial frontal gyrus, superior parietal lobe, middle temporal gyrus, rostral anterior cingulate cortex (rACC), lentiform nucleus, insula, and contralateral thalamus. Stimulation at ST44 selectively activated ipsilateral secondary somatosensory area (SII), contralateral middle frontal gyrus, inferior frontal gyrus, lingual gyrus, lentiform nucleus, and bilateral posterior cingulate cortex (PCC). Conclusions. Acupuncture at adjacent acupoints elicits distinct cerebral activation patterns, and those specific patterns might be involved in the mechanism of the specific therapeutic effects of different acupoints. PMID:23762172

  14. Divergent viral presentation among human tumors and adjacent normal tissues.

    PubMed

    Cao, Song; Wendl, Michael C; Wyczalkowski, Matthew A; Wylie, Kristine; Ye, Kai; Jayasinghe, Reyka; Xie, Mingchao; Wu, Song; Niu, Beifang; Grubb, Robert; Johnson, Kimberly J; Gay, Hiram; Chen, Ken; Rader, Janet S; Dipersio, John F; Chen, Feng; Ding, Li

    2016-01-01

    We applied a newly developed bioinformatics system called VirusScan to investigate the viral basis of 6,813 human tumors and 559 adjacent normal samples across 23 cancer types and identified 505 virus positive samples with distinctive, organ system- and cancer type-specific distributions. We found that herpes viruses (e.g., subtypes HHV4, HHV5, and HHV6) that are highly prevalent across cancers of the digestive tract showed significantly higher abundances in tumor versus adjacent normal samples, supporting their association with these cancers. We also found three HPV16-positive samples in brain lower grade glioma (LGG). Further, recurrent HBV integration at the KMT2B locus is present in three liver tumors, but absent in their matched adjacent normal samples, indicating that viral integration induced host driver genetic alterations are required on top of viral oncogene expression for initiation and progression of liver hepatocellular carcinoma. Notably, viral integrations were found in many genes, including novel recurrent HPV integrations at PTPN13 in cervical cancer. Finally, we observed a set of HHV4 and HBV variants strongly associated with ethnic groups, likely due to viral sequence evolution under environmental influences. These findings provide important new insights into viral roles of tumor initiation and progression and potential new therapeutic targets. PMID:27339696

  15. Osteochondroma of the hip with adjacent bursal chondromatosis.

    PubMed

    Gould, Elaine S; Baker, Kevin S; Huang, Mingqian; Khan, Fazel; Hoda, Syed

    2014-12-01

    It is well established that irregular bursae can form adjacent to an osteochondroma (bursa exostotica) as a result of mechanical irritation and that these bursae can be complicated by inflammation, hemorrhage, or infection. Bursal chondromatosis is a rare complication, with only seven published cases in the literature according to our searches. We present the case of a 53-year-old female who presented with slowly progressive left hip/thigh pain and was found to have an osteochondroma arising from the lesser trochanter with numerous ossified bodies in the adjacent soft tissues. MRI demonstrated osteochondral bodies in a fluid-filled bursa adjacent to the osteochondroma, with several of the bodies noted to be fairly displaced from the osteochondroma cartilaginous cap. At surgery, the osteochondroma was removed and numerous bodies of varying sizes were excised, some of which were noted to be adherent to the bursal lining and others that were separated/distant from the cartilage cap. The question arises as to whether this process represents bursal chondromatosis resulting from benign neoplasia of cells lining the abnormal bursa, "cartilage shedding" from the osteochondromatous cap, or both. The purpose in presenting this case is to introduce a rare complication of an osteochondroma, demonstrate that soft tissue calcification and osteochondral densities displaced from an underlying osteochondroma are not always the result of sarcomatous degeneration, and provide support for the theory that cells lining a bursa in a nonphysiologic location can undergo benign neoplasia with subsequent formation of osteochondral bodies. PMID:25001874

  16. Divergent viral presentation among human tumors and adjacent normal tissues

    PubMed Central

    Cao, Song; Wendl, Michael C.; Wyczalkowski, Matthew A.; Wylie, Kristine; Ye, Kai; Jayasinghe, Reyka; Xie, Mingchao; Wu, Song; Niu, Beifang; Grubb, Robert; Johnson, Kimberly J.; Gay, Hiram; Chen, Ken; Rader, Janet S.; Dipersio, John F.; Chen, Feng; Ding, Li

    2016-01-01

    We applied a newly developed bioinformatics system called VirusScan to investigate the viral basis of 6,813 human tumors and 559 adjacent normal samples across 23 cancer types and identified 505 virus positive samples with distinctive, organ system- and cancer type-specific distributions. We found that herpes viruses (e.g., subtypes HHV4, HHV5, and HHV6) that are highly prevalent across cancers of the digestive tract showed significantly higher abundances in tumor versus adjacent normal samples, supporting their association with these cancers. We also found three HPV16-positive samples in brain lower grade glioma (LGG). Further, recurrent HBV integration at the KMT2B locus is present in three liver tumors, but absent in their matched adjacent normal samples, indicating that viral integration induced host driver genetic alterations are required on top of viral oncogene expression for initiation and progression of liver hepatocellular carcinoma. Notably, viral integrations were found in many genes, including novel recurrent HPV integrations at PTPN13 in cervical cancer. Finally, we observed a set of HHV4 and HBV variants strongly associated with ethnic groups, likely due to viral sequence evolution under environmental influences. These findings provide important new insights into viral roles of tumor initiation and progression and potential new therapeutic targets. PMID:27339696

  17. Using BRDFs for accurate albedo calculations and adjacency effect corrections

    SciTech Connect

    Borel, C.C.; Gerstl, S.A.W.

    1996-09-01

    In this paper the authors discuss two uses of BRDFs in remote sensing: (1) in determining the clear sky top of the atmosphere (TOA) albedo, (2) in quantifying the effect of the BRDF on the adjacency point-spread function and on atmospheric corrections. The TOA spectral albedo is an important parameter retrieved by the Multi-angle Imaging Spectro-Radiometer (MISR). Its accuracy depends mainly on how well one can model the surface BRDF for many different situations. The authors present results from an algorithm which matches several semi-empirical functions to the nine MISR measured BRFs that are then numerically integrated to yield the clear sky TOA spectral albedo in four spectral channels. They show that absolute accuracies in the albedo of better than 1% are possible for the visible and better than 2% in the near infrared channels. Using a simplified extensive radiosity model, the authors show that the shape of the adjacency point-spread function (PSF) depends on the underlying surface BRDFs. The adjacency point-spread function at a given offset (x,y) from the center pixel is given by the integral of transmission-weighted products of BRDF and scattering phase function along the line of sight.

  18. Relevance of estuaries adjacent to megalopolis as modifiers of internal shelf areas

    NASA Astrophysics Data System (ADS)

    Wagener, Angela; Lazzzari, Leticia; Carreira, Renato; Farias, Cassia; Mauad, Cristiane

    2014-05-01

    Guanabara Bay located in the humid tropical region is a eutrophic estuarine system bordered by the second largest metropolitan area of Brazil. Human intervention resulted in water conditions ranging from complete anoxia in the polluted inner bay area to the adjacent, relatively pristine, open coastal area. In the present work the goals were to estimate nutrients and carbon fluxes between the bay and the adjacent coastal waters and to characterize by using stable isotopes, hydrocarbons and sterols the provenance of the exported/imported organic matter. Water samples were collected from three different depths over 25 hours cycles in the wet and dry seasons at a single station strategically positioned in the bay. Measurements included CTD, nutrients, chlorophylls, DOC, POC, PN, δ13C and δ15N, hydrocarbons and sterols in SPM. Most substances showed higher concentrations in ebb tide events and through statistical tools a significant difference between the campaigns was proved. The fluxes estimated on annual basis revealed the expressive exportation to the inner continental shelf of 1.27x104 Kmol DIN yr-1, 9.52x102 Kmol DIP yr-1, 2.65x104 tons DOC yr-1, 1.96x104 tons COP yr-1, 2.96x104 tons NP yr-1.

  19. Texture analysis of radiometric signatures of new sea ice forming in Arctic leads

    NASA Technical Reports Server (NTRS)

    Eppler, Duane T.; Farmer, L. Dennis

    1991-01-01

    Analysis of 33.6-GHz, high-resolution, passive microwave images suggests that new sea ice accumulating in open leads is characterized by a unique textural signature which can be used to discriminate new ice forming in this environment from adjacent surfaces of similar radiometric temperature. Ten training areas were selected from the data set, three of which consisted entirely of first-year ice, four entirely of multilayer ice, and three of new ice in open leads in the process of freezing. A simple gradient operator was used to characterize the radiometric texture in each training region in terms of the degree to which radiometric gradients are oriented. New ice in leads has a sufficiently high proportion of well-oriented features to distinguish it uniquely from first-year ice and multiyear ice. The predominance of well-oriented features probably reflects physical processes by which new ice accumulates in open leads. Banded structures, which are evident in aerial photographs of new ice, apparently give rise to the radiometric signature observed, in which the trend of brightness temperature gradients is aligned parallel to lead trends. First-year ice and multiyear ice, which have been subjected to a more random growth and process history, lack this banded structure and therefore are characterized by signatures in which well-aligned elements are less dominant.

  20. Nocturnal water loss in mature subalpine Eucalyptus delegatensis tall open forests and adjacent E. pauciflora woodlands

    PubMed Central

    Buckley, Thomas N; Turnbull, Tarryn L; Pfautsch, Sebastian; Adams, Mark A

    2011-01-01

    We measured sap flux (S) and environmental variables in four monospecific stands of alpine ash (Eucalyptus delegatensis R. Baker, AA) and snowgum (E. pauciflora Sieb. ex Spreng., SG) in Australia's Victorian Alps. Nocturnal S was 11.8 ± 0.8% of diel totals. We separated transpiration (E) and refilling components of S using a novel modeling approach based on refilling time constants. The nocturnal fraction of diel water loss (fn) averaged 8.6 ± 0.6% for AA and 9.8 ± 1.7% for SG; fn differed among sites but not species. Evaporative demand (D) was the strongest driver of nocturnal E (En). The ratio En/D (Gn) was positively correlated to soil moisture in most cases, whereas correlations between wind speed and Gn varied widely in sign and strength. Our results suggest (1) the large, mature trees at our subalpine sites have greater fn than the few Australian native tree species that have been studied at lower elevations, (2) AA and SG exhibit similar fn despite very different size and life history, and (3) fn may differ substantially among sites, so future work should be replicated across differing sites. Our novel approach to quantifying fn can be applied to S measurements obtained by any method. PMID:22393512

  1. Functional angiocoupling between follicles and adjacent corpus luteum in heifers.

    PubMed

    Ginther, O J; Siddiqui, M A R; Baldrighi, J M

    2016-07-15

    In single ovulating cattle, ipsilateral versus contralateral interovarian relationships refer to a dominant follicle (DF) and CL in the same versus opposite ovaries. The ipsilateral relationship consists of the DF-CL and the devoid (no DF or CL) intraovarian pattern, and the contralateral relationship consists of the DF pattern and the CL pattern. The DF-CL pattern involves positive effects on both the DF and CL when adjacent (≤3-mm apart) versus separated as follows: greater diameter of DF (e.g., 10.5 ± 0.4 vs. 9.0 ± 0.4 mm), greater percentage of the DF wall with color Doppler signals of blood flow (40.2% ± 2.0% vs. 24.5% ± 1.9%), greater cross-sectional area of the CL (2.2 ± 0.1 vs. 1.8 ± 0.2 cm(2)), and greater percentage of the entire CL with blood flow signals (51.8% ± 1.2% vs. 42.5% ± 3.1%). Additional examples of positive coupling are (1) future DF on Day 0 (day of ovulation) is closer to the CL than the future largest subordinate and (2) diameter of growing follicles on Day 0 and the growth rate on Days 0 to 2 are greater for follicles that are adjacent than separated from the CL. An example of a negative intraovarian effect is decreasing diameter and loss of future DF status of a largest follicle when adjacent to a regressing CL. The impact of the continuity of ovarian angioarchitecture during the periovulatory follicular wave was exemplified in 17 of 18 waves by conversion of an ovary with only the preovulatory follicle to the postovulatory DF-CL pattern. Functional angiocoupling from commonality in angioarchitecture of the DF and adjacent CL would account for both the positive two-way coupling between DF and CL during the luteal phase and the negative effect of a regressing CL on an adjacent follicle during luteolysis. PMID:27056414

  2. Thermo-mechanical Model of the Dead Sea Transform

    NASA Astrophysics Data System (ADS)

    Sobolev, S. V.; Babeyko, A. Y.; Garfunkel, Z.

    2002-12-01

    The Dead Sea transform system (DST) is the boundary between the Arabian and African plates, where left-lateral transform motion has largely accommodated the opening of the Red Sea basin during the last 15-20 My. One of the key questions related to this plate boundary is whether the DST crosses the crust and mantle lithosphere, and how the rheologically different units composing the lithosphere interact during strong deformation? Another major question is how important is the rifting (transform-perpendicular extension) deformation component at the DST? We address these questions using the internally consistent finite element thermo-mechanical modelling of the lithospheric deformation constrained by high-resolution geophysical observations and especially by the recent geophysical data of the DESERT Project. From our modelling, we conclude that the DST lithospheric structure is controlled by the plate-scale transform displacement within a relatively cold and strong lithosphere. In such a lithosphere, shear strain is localized in a narrow (20-40 km wide) vertical decoupling zone (VDZ), which crosses the entire lithosphere and even continues into the asthenosphere. In the upper crust the deformation localizes at one or two major faults located at the top of this zone. The location of the VDZ is controlled by the temperature of the uppermost mantle prior to the transform motion. Most of the lithospheric structures imaged along the DESERT seismic line is explained by the 105 km transform motion combined with less than 4 km transform-perpendicular extension. Uplift of the Arabian Shield adjacent to the DST can be explained by young (<20 Ma) thinning of the lithosphere at and east of the plate boundary. Such lithospheric thinning is consistent with seismological observations, with the low present-day surface heat flow and with the high temperatures derived from mantle xenoliths brought up by Neogene-Quaternary basalts. Taking into account the timing of the onset of the

  3. Foraminiferal biodiversity associated with cold-water coral carbonate mounds and open slope of SE Rockall Bank (Irish continental margin—NE Atlantic)

    NASA Astrophysics Data System (ADS)

    Morigi, C.; Sabbatini, A.; Vitale, G.; Pancotti, I.; Gooday, A. J.; Duineveld, G. C. A.; De Stigter, H. C.; Danovaro, R.; Negri, A.

    2012-01-01

    Cold-water coral (CWC) ecosystems are hotspots of macro- and microfaunal biodiversity and provide refuge for a wide variety of deep-sea species. We investigated how the abundance and biodiversity of 'live' (Rose Bengal stained) foraminifera varies with, and is related to, the occurrence of CWC on the Rockall Bank (NE Atlantic). Qualitative and quantitative analyses were performed on 21 replicate samples from 8 deep-sea stations, including 4 stations on CWC-covered carbonate mounds at depths of 567-657 m, and 4 stations on the adjacent slope at depths of 469-1958 m where CWC were absent. This sampling strategy enabled us to demonstrate that sediments surrounding the living CWC were characterised by higher foraminiferal abundance and biodiversity than open-slope sediments from the same area. A total of 163 foraminiferal species was identified. The dominant species in CWC sediments were: Spirillina vivipara, Allogromiid sp. 1, Globocassidulina subglobosa, Adercotryma wrighti, Eponides pusillus, Ehrenbergina carinata, Planulina ariminensis, Trochammina inflata and Paratrochammina challengeri. Foraminifera were nearly absent in adjacent open slope areas subject to strong tidal currents and characterised by coarse grained deposits. We suggest that CWC create a heterogeneous three-dimensional substrate offering microhabitats to a diverse benthic foraminiferal community.

  4. Role of adjacency-matrix degeneracy in maximum-entropy-weighted network models

    NASA Astrophysics Data System (ADS)

    Sagarra, O.; Pérez Vicente, C. J.; Díaz-Guilera, A.

    2015-11-01

    Complex network null models based on entropy maximization are becoming a powerful tool to characterize and analyze data from real systems. However, it is not easy to extract good and unbiased information from these models: A proper understanding of the nature of the underlying events represented in them is crucial. In this paper we emphasize this fact stressing how an accurate counting of configurations compatible with given constraints is fundamental to build good null models for the case of networks with integer-valued adjacency matrices constructed from an aggregation of one or multiple layers. We show how different assumptions about the elements from which the networks are built give rise to distinctively different statistics, even when considering the same observables to match those of real data. We illustrate our findings by applying the formalism to three data sets using an open-source software package accompanying the present work and demonstrate how such differences are clearly seen when measuring network observables.

  5. Habitats of North American sea ducks.

    USGS Publications Warehouse

    Derksen, Dirk V.; Petersen, Margaret R.; Savard, Jean-Pierre L.

    2015-01-01

    Breeding, molting, fall and spring staging, and wintering habitats of the sea duck tribe Mergini are described based on geographic locations and distribution in North America, geomorphology, vegetation and soil types, and fresh water and marine characteristics. The dynamics of habitats are discussed in light of natural and anthropogenic events that shape areas important to sea ducks. Strategies for sea duck habitat management are outlined and recommendations for international collaboration to preserve key terrestrial and aquatic habitats are advanced. We follow the definition of habitat advanced by Odum (1971), which is the place or space where an organism lives. Weller (1999) emphasized that habitats for waterbirds required presence of sufficient resources (i.e., food, water, cover, space) for maintenance during a portion of their annual cycle. Habitats exploited by North American sea ducks are diverse, widespread across the continent and adjacent marine waters and until recently, most were only superficially known. Even following a 15-year-long effort through the Sea Duck Joint Venture and U.S. and Canadian Endangered/Threatened Species programs to fund research focused on sea duck habitats there are still important gaps in our understanding of key elements required by some species during various life stages. Importantly, many significant habitats, especially staging and wintering sites, have been and continue to be destroyed or altered, largely as a result of anthropogenic effects. Our goal here is to develop a comprehensive summary of marine, freshwater, and terrestrial habitats and their characteristics by considering sea duck species with similar needs as groups (e.g., eiders) within the tribe Mergini. Additionally, this chapter will examine threats and changes to sea duck habitats from human-caused and natural events. Finally, we will evaluate conservation and management programs underway or available for maintenance and enhancement of habitats critical for

  6. Evidence for a thick oceanic crust adjacent to the Norwegian Margin

    NASA Astrophysics Data System (ADS)

    Mutter, John C.; Talwani, Manik; Stoffa, Paul L.

    1984-01-01

    The oceanic crust created during this first few million years of accretion in the Norwegian-Greenland Sea lies at an unusually shallow depth for its age, has a smooth upper surface, and in many places the results of multichannel seismic reflection profiling reveal that its upper layers comprise a remarkable sequence of arcuate, seaward-dipping reflectors. These have been attributed to lava flows generated during a brief period of subaerial seafloor spreading. We describe the results of inversions of digitally recorded sonobuoy measurements and two-ship expanded spread profiles collected over the oceanic crust adjacent to the Norwegian passive margin. We find that the crust of the deep Lofoten Basin is indistinguishable from normal oceanic crust in thickness and structure. Closer to the margin we observe up to a four times expansion in thickness of layers with velocities equal to those of oceanic layer 2, while the layer 3 region retains approximately the same thickness. The area over which the seaward-dipping reflectors can be observed on reflection profiles corresponds to the region of greatest expansion in "Layer 2" thickness. In the very oldest crust immediately adjacent to an escarpment that probably marks the continent-ocean boundary, we see evidence for a low velocity zone overlying an indistinct reflector that may mark the dyke-lava interface in the thick crust. Comparing the structure of the thick crust to that of eastern Iceland, we find a strong resemblance, especially in the expansion in thickness of material with layer 2 velocities. These results support the suggestion that during the earliest stages of spreading extrusive volcanism at the ridge crest was unusually voluminous, building a thick pile of lavas erupted from a subaerial spreading center.

  7. The ground beetles (Coleoptera: Carabidae) of the Strandzha Mountain and adjacent coastal territories (Bulgaria and Turkey)

    PubMed Central

    Guéorguiev, Borislav

    2016-01-01

    Abstract Background The knowledge of the ground-beetle fauna of Strandzha is currently incomplete, and is largely based on data from the Bulgarian part of the region and on records resulting from casual collecting. This study represents a critical revision of the available literature, museum collections and a three years field study of the carabid beetles of the Bulgarian and Turkish parts of Strandzha Mountain and the adjacent Black Sea Coast territories. New information A total of 328 species and subspecies of Carabidae, belonging to 327 species from the region of Strandzha Mountain and adjacent seacoast area, have been listed. Of these, 77 taxa represent new records for the Bulgarian part of the region, and 110 taxa new records for Turkish part of the studied region. Two taxa, one subgenus (Haptotapinus Reitter, 1886) and one species (Pterostichus crassiusculus), are new to the fauna of Bulgaria. Based on a misidentification, the species Apotomus testaceus is excluded from the list of the Bulgarian fauna. Seven species (Carabus violaceus azurescens, Apotomus rufus, Platynus proximus, Molops alpestris kalofericus, M. dilatatus angulicollis, Pterostichus merklii, and Calathus metallicus) are treated as doubtful for the regional fauna, and one (Apotomus rufus) also for the Bulgarian fauna. Altogether, 43 taxa collected in the Turkish part of the region are new for European Turkey. New taxa for Turkey are the genera Myas and Oxypselaphus, the subgenus Feronidius, and nine species and subspecies (Carabus granulatus granulatus, Dyschirius tristis, Bembidion normannum apfelbecki, B. subcostatum vau, Acupalpus exiguus, Myas chalybaeus, Oxypselaphus obscurus, Pterostichus leonisi, Pt. melas). In addition, there are a further seven species that are here confirmed for Turkey. PMID:27099564

  8. Copper, zinc and cadmium in benthic organisms from the Java Sea and estuarine and coastal areas around East Java

    NASA Astrophysics Data System (ADS)

    Everaarts, J. M.; Boon, J. P.; Kastoro, W.; Fischer, C. V.; Razak, H.; Sumanta, I.

    A study was made of the concentrations of copper, zinc and cadmium in benthic organisms, representing the phyla Mollusca, Arthropoda, Echinodermata and Pisces, from the riverine and estuarine areas of the rivers Brantas and Solo (East Java) and the adjacent coastal area. Moreover, an assessment was made of the contamination of the benthic biota with these elements in the Java Sea and Bali Sea. Benthic organisms show a species-specific uptake pattern for each element. Compared to the same type of animals from estuaries and coastal areas in temperate regions of western Europe, the concentrations of cadmium are considerably higher, while copper and zinc concentrations are somewhat lower. There is no general trend in concentration levels of the metals in specimens from rivers, estuaries, coastal zone and open sea. In some groups of organisms ( e.g. shrimp, starfish) the concentrations of copper and zinc are highest in specimens from rivers and estuaries. In contrast, cadmium concentration levels in e.g. crab, shrimp and squid are lowest in riverine and estuarine areas. Significant differences in metal concentrations in these organisms were found between the dry monsoon period (July, August) and the beginning of the wet monsoon (November, December). No relationship existed between the metal concentration of the organisms and the silt fraction of the sediment (grain size < 63 μm) or the bulk sediment.

  9. Record Arctic Sea Ice Loss in 2007

    NASA Technical Reports Server (NTRS)

    2007-01-01

    This image of the Arctic was produced from sea ice observations collected by the Advanced Microwave Scanning Radiometer (AMSR-E) Instrument on NASA's Aqua satellite on September 16, overlaid on the NASA Blue Marble. The image captures ice conditions at the end of the melt season. Sea ice (white, image center) stretches across the Arctic Ocean from Greenland to Russia, but large areas of open water were apparent as well. In addition to record melt, the summer of 2007 brought an ice-free opening though the Northwest Passage that lasted several weeks. The Northeast Passage did not open during the summer of 2007, however, as a substantial tongue of ice remained in place north of the Russian coast. According to the National Snow and Ice Data Center (NSIDC), on September 16, 2007, sea ice extent dropped to 4.13 million square kilometers (1.59 million square miles)--38 percent below average and 24 percent below the 2005 record.

  10. Sea level and geostrophic current control on carbonate shelf-slope depositional sequences and erosional patterns, south Florida platform margin

    SciTech Connect

    Locker, S.D.; Hine, A.C. ); Shinn, E.A. )

    1991-03-01

    High-resolution seismic reflection profiles across the shelf-slope margin between the Dry Tortugas and Key West, Florida, indicate that sea-level fluctuations and the eastward flowing Florida Current are major controls on late Quaternary sequence stratigraphy. The study area, a transition zone between the open south Florida shelf and the lower Florida Keys island/reef system, is typified by a shallow shelf with reef margin adjacent to a deeper lower-shelf/slope. The lower-shelf/slope is composed of stacked or prograding sequences that downlap and pinchout on the Pourtales Terrace. Strike oriented stratigraphic sections exhibit many sea-level controlled features such as lowstand erosion, transgressive unconformities, and highstand system tracts. Lowstand reefs, notches, or barriers are observed as deep as 150 m below present sea level. Depositional styles change along-slope from west to east. The western portion of the study area is characterized by thick, low-amplitude, prograding sequences related to abundant supply of sediment through off-shelf transport during high sea-levels as well as along-slope reworking by Florida current. Part of this section has been severely eroded by along-slope currents producing localized cut-and-fill structures and widespread erosional unconformities. To the east, a thinner section of high-amplitude reflections is common seaward of the lower Florida Keys reef tract system. This study provides a new evidence of how strong geostrophic boundary currents along with fluctuating sea levels have interacted to control depositional sequences on a carbonate slope in the Florida/Bahamas platform complex.

  11. Pollution in the Baltic Sea.

    PubMed

    Rheinheimer, G

    1998-07-01

    The Baltic Sea is almost totally surrounded by land and therefore more endangered by pollution than other marine areas. The sources of marine pollution are municipal and industrial waste inputs directly into the sea or via rivers, and atmospheric inputs mainly from traffic and agriculture. The increase of inorganic plant nutrients (NH3, NOx, PO4) caused eutrophication and consequent oxygen depletion in coastal bottom waters as well as in the depths of the open sea. In the anoxic sediments, hydrogen sulfide can be produced by protein-decomposing and sulfate-reducing bacteria. The bottom fauna will be destroyed and only H2S tolerant microorganisms can survive. Originating from cellulose manufacturing and from paper mills, large amounts of poisonous chlorinated compounds contaminated the coastal waters of Sweden and Finland until the 1980s. Most of this material is still present in sediments of the central Baltic Sea and can be resuspended by near bottom currents. To reduce pollution and improve the situation in the Baltic Sea, the surrounding countries organized the Helsinki Convention, which came into force on 3.5.1980. The Helsinki Commission (HELCOM) founded in 1974 acts as coordinator and is responsible for the enforcement of the Baltic monitoring program and international research projects. The activities of HELCOM have led to the reduction of dangerous pollutants which in turn has caused the regeneration of flora and fauna in some areas. Further improvements can be expected. PMID:9722964

  12. Quantifying 10 years of Improvements in Earthquake and Tsunami Monitoring in the Caribbean and Adjacent Regions

    NASA Astrophysics Data System (ADS)

    von Hillebrandt-Andrade, C.; Huerfano Moreno, V. A.; McNamara, D. E.; Saurel, J. M.

    2014-12-01

    The magnitude-9.3 Sumatra-Andaman Islands earthquake of December 26, 2004, increased global awareness to the destructive hazard of earthquakes and tsunamis. Post event assessments of global coastline vulnerability highlighted the Caribbean as a region of high hazard and risk and that it was poorly monitored. Nearly 100 tsunamis have been reported for the Caribbean region and Adjacent Regions in the past 500 years and continue to pose a threat for its nations, coastal areas along the Gulf of Mexico, and the Atlantic seaboard of North and South America. Significant efforts to improve monitoring capabilities have been undertaken since this time including an expansion of the United States Geological Survey (USGS) Global Seismographic Network (GSN) (McNamara et al., 2006) and establishment of the United Nations Educational, Scientific and Cultural Organization (UNESCO) Intergovernmental Coordination Group (ICG) for the Tsunami and other Coastal Hazards Warning System for the Caribbean and Adjacent Regions (CARIBE EWS). The minimum performance standards it recommended for initial earthquake locations include: 1) Earthquake detection within 1 minute, 2) Minimum magnitude threshold = M4.5, and 3) Initial hypocenter error of <30 km. In this study, we assess current compliance with performance standards and model improvements in earthquake and tsunami monitoring capabilities in the Caribbean region since the first meeting of the UNESCO ICG-Caribe EWS in 2006. The three measures of network capability modeled in this study are: 1) minimum Mw detection threshold; 2) P-wave detection time of an automatic processing system and; 3) theoretical earthquake location uncertainty. By modeling three measures of seismic network capability, we can optimize the distribution of ICG-Caribe EWS seismic stations and select an international network that will be contributed from existing real-time broadband national networks in the region. Sea level monitoring improvements both offshore and

  13. Hydrological and biogeochemical Controls on Absorption and Fluorescence of Dissolved Organic Matter in the Northern South China Sea

    NASA Astrophysics Data System (ADS)

    Guo, Weidong; Wang, Chao; Li, Yan; Li, Yizhen; Song, Guodong; Wang, Lei; Cheng, Yuanyue

    2016-04-01

    Absorption and fluorescence of dissolved organic matter (DOM) were investigated in the northern South China Sea (SCS) and adjacent Kuroshio section of the West Philippine Sea (WPS). Two humic-like (C1, C2) and three protein-like (C3-C5) fluorescent components were identified using parallel factor analysis (PARAFAC). chromophoric DOM (CDOM) and fluorescent DOM (FDOM) in the northern SCS showed similar distribution patterns to the adjacent Kuroshio section and global open ocean, yet exhibited higher values in the whole water column. An isopycnal mixing model was adopted to quantify the difference in CDOM and FDOM in the euphotic zone between the northern SCS and WPS. Results showed that CDOM and humic-like FDOM were mainly modulated by Kuroshio intrusion, while protein-like FDOM were more affected by biological activities. At mid-depth, significant linear relationships between a350, C1, C2 and apparent oxygen utilization (AOU) suggested that CDOM and humic-like FDOM were produced in situ coupled to remineralization of biogenic sinking particle. Excess humic-like FDOM in the intermediate water of northern SCS were determined and more proportion of high molecular weight organic carbon was exported to the open ocean interior. In addition, regional distribution patterns of CDOM and FDOM were also tuned by mesoscale processes in the northern SCS. Different CDOM and FDOM components in the euphotic zone have apparently different responses for changes of biological activity and vertical mixing driven by eddies. Moreover, cold eddy could capture more sinking particles and finally increase the accumulation of bio-refractory CDOM and humic-like FDOM in the dark ocean. Finally, we demonstrated that the ratio of two humic-like FDOM (C1:C2, or peak C:M) may be a good indicator of water mixing, evolution of mesoscale eddies, photochemistry in the upper water and remineralization in the deeper layer.

  14. Study of Local Seismic Events in Lithuania and Adjacent Areas Using Data from the PASSEQ Experiment

    NASA Astrophysics Data System (ADS)

    Janutyte, Ilma; Kozlovskaya, Elena; Motuza, Gediminas

    2013-05-01

    The territory of Lithuania and adjacent areas of the East European Craton have always been considered a region of low seismicity. Two recent earthquakes with magnitudes of more than 5 in the Kaliningrad District (Russian Federation) on 21 September 2004 motivated re-evaluation of the seismic hazard in Lithuania and adjacent territories. A new opportunity to study seismicity in the region is provided by the PASSEQ (Pasive Seismic Experiment) project that aimed to study the lithosphere-asthenosphere structure around the Trans-European Suture Zone. Twenty-six seismic stations of the PASSEQ temporary seismic array were installed in the territory of Lithuania. The stations recorded a number of local and regional seismic events originating from Lithuania and adjacent areas. This data can be used to answer the question of whether there exist seismically active tectonic zones in Lithuania that could be potentially hazardous for critical industrial facilities. Therefore, the aim of this paper is to find any natural tectonic seismic events in Lithuania and to obtain more general view of seismicity in the region. In order to do this, we make a manual review of the continuous data recorded by the PASSEQ seismic stations in Lithuania. From the good quality data, we select and relocate 45 local seismic events using the well-known LocSAT and VELEST location algortithms. In order to discriminate between possible natural events, underwater explosions and on-shore blasts, we analyse spatial distribution of epicenters and temporal distribution of origin times and perform both visual analysis of waveforms and spectral analysis of recordings. We show that the relocated seismic events can be grouped into five clusters (groups) according to their epicenter coordinates and origin and that several seismic events might be of tectonic origin. We also show that several events from the off-shore region in the Baltic Sea (at the coasts of the Kaliningrad District of the Russian Federation) are

  15. Sea Ice, Climate and Fram Strait

    NASA Technical Reports Server (NTRS)

    Hunkins, K.

    1984-01-01

    When sea ice is formed the albedo of the ocean surface increases from its open water value of about 0.1 to a value as high as 0.8. This albedo change effects the radiation balance and thus has the potential to alter climate. Sea ice also partially seals off the ocean from the atmosphere, reducing the exchange of gases such as carbon dioxide. This is another possible mechanism by which climate might be affected. The Marginal Ice Zone Experiment (MIZEX 83 to 84) is an international, multidisciplinary study of processes controlling the edge of the ice pack in that area including the interactions between sea, air and ice.

  16. Exophytic Atheroma Mimicking Papillary Fibroelastoma Adjacent to the Aortic Valve.

    PubMed

    Cho, Tomoki; Tokunaga, Shigehiko; Yasuda, Shota; Izubuchi, Ryo; Masuda, Munetaka

    2015-09-01

    Follow-up echocardiography in a 69-year-old man with alcoholic cardiomyopathy showed a mass above the aortic valve near the left coronary ostium. Transesophageal echocardiography and computed tomography suggested a papillary fibroelastoma with a high risk of embolism. At operation we found an exophytic atheroma adjacent to the left coronary artery orifice. The atheroma was removed, and the patient made an uneventful recovery. We describe this very rare case of an exophytic atheroma mimicking a papillary fibroelastoma situated at the left coronary orifice. PMID:26354633

  17. Compression of adjacent anatomical structures by pulmonary artery dilation.

    PubMed

    Dakkak, Wael; Tonelli, Adriano R

    2016-06-01

    Pulmonary hypertension is the commonest condition leading to dilated pulmonary artery. We describe three different types of compression of adjacent anatomical structures by dilated pulmonary arteries. We included involvement of the left main coronary artery, left recurrent laryngeal nerve and tracheobronchial tree. Compression of these structures can cause major complications such as myocardial ischemia, hoarseness and major airway stenosis. We present a case for each scenario and review the literature for each of these complications, focusing on patients' characteristics and contemporary management. PMID:26898826

  18. Synthesis of a Molecule with Four Different Adjacent Pnictogens.

    PubMed

    Hinz, Alexander; Schulz, Axel; Villinger, Alexander

    2016-08-22

    The synthesis of a molecule containing four adjacent different pnictogens was attempted by conversion of a Group 15 allyl analogue anion [Mes*NAsPMes*](-) (Mes*=2,4,6-tri-tert-butylphenyl) with antimony(III) chloride. A suitable precursor is Mes*N(H)AsPMes* (1) for which several syntheses were investigated. The anions afforded by deprotonation of Mes*N(H)AsPMes* were found to be labile and, therefore, salts could not be isolated. However, the in situ generated anions could be quenched with SbCl3 , yielding Mes*N(SbCl2 )AsPMes* (4). PMID:27377437

  19. Stereoselective Organocatalytic Synthesis of Oxindoles with Adjacent Tetrasubstituted Stereocenters.

    PubMed

    Engl, Oliver D; Fritz, Sven P; Wennemers, Helma

    2015-07-01

    Oxindoles with adjacent tetrasubstituted stereocenters were obtained in high yields and stereoselectivities by organocatalyzed conjugate addition reactions of monothiomalonates (MTMs) to isatin-derived N-Cbz ketimines. The method requires only a low catalyst loading (2 mol %) and proceeds under mild reaction conditions. Both enantiomers are accessible in good yields and excellent stereoselectivities by using either Takemoto's catalyst or a cinchona alkaloid derivative. The synthetic methodology allowed establishment of a straightforward route to derivatives of the gastrin/cholecystokinin-B receptor antagonist AG-041R. PMID:26033441

  20. Interaction of Cracks Between Two Adjacent Indents in Glass

    NASA Technical Reports Server (NTRS)

    Choi, S. R.; Salem, J. A.

    1993-01-01

    Experimental observations of the interaction behavior of cracks between two adjacent indents were made using an indentation technique in soda-lime glass. It was specifically demonstrated how one indent crack initiates and propagates in the vicinity of another indent crack. Several types of crack interactions were examined by changing the orientation and distance of one indent relative to the other. It was found that the residual stress field produced by elastic/plastic indentation has a significant influence on controlling the mode of crack interaction. The interaction of an indent crack with a free surface was also investigated for glass and ceramic specimens.

  1. CLOUD PEAK PRIMITIVE AREA AND ADJACENT AREAS, WYOMING.

    USGS Publications Warehouse

    Kiilsgaard, Thor H.; Patten, Lowell L.

    1984-01-01

    The results of a mineral survey of the Cloud Peak Primitive Area and adjacent areas in Wyoming indicated little promise for the occurrence of mineral resources. There are some prospect workings, particularly in the northern part of the area, but in none of them were there indications that ore had been mined. Samples from the workings, from nearby rocks and sediments from streams that drain the area did not yield any metal values of significance. The crystalline rocks that underlie the area do not contain oil and gas or coal, products that are extracted from the younger rocks that underlie basins on both sides of the study area.

  2. Past and present Aral Sea

    NASA Astrophysics Data System (ADS)

    Dukhovniy, Viktor; Stulina, Galina; Eshchanov, Odylbek

    2013-04-01

    organized in 2005-2009 sixth expeditions for complex remote sensing and ground investigations Aral Sea former bottom that were complemented in 2010 -2011 by two expeditions with GFZ. As a result, the landscape, soils and environment mapping was done with determination of ecologically unstable zones and assessment total change of lands situation compared with the pre-independence time. Moreover - methodic of monitoring water, environment and hydro geological indicators on the all deltas area was elaborated, organized its testing and combined with remote sensing data on Amudarya delta for 2009-2012. It permits to SIC ICWC to organize systematic permanent (decadal) monitoring and recording of size, volume and level of water in Aral Sea. Since the beginning of regular observations over the Aral Sea level, 2 periods can be emphasized: 1. Conditionally natural period - 1911-1960 - characterized by a relatively stable hydrological regime, with fluctuations in the level around 53 m and the range of inter-annual fluctuations at no more than 1 m., when the sea received annually about a half of the run-off in the Syrdarya and Amudarya Rivers, i.e. 50-60 km3/yr. 2. Intensive anthropogenic impact period - since the 1960s, a vast extension of irrigable land was carried out in Central Asia that resulted in intensive diversion of river run-off. Since then, the sea level has been falling steadily, causing a dramatic reduction in the water surface area, a decrease in water volume and depths, great changes in shoreline configuration and an expansion of the desert areas adjacent to the Aral Sea. From 1960-1985, when the sea was an integral water body, slight lowering in the sea level took place until the 1970s, when the sea-level decreased with the mean level lowering 1 m. The desiccation process accelerated visibly from the mid 1970s. In 1975-1980, the level decreased by 0.65 m a year on average. Moreover, the level dropped greatly, when the run-off of the Amudarya did not reach the Aral Sea

  3. Sea Ice

    NASA Technical Reports Server (NTRS)

    Parkinson, Claire L.; Cavalieri, Donald J.

    2005-01-01

    Sea ice covers vast areas of the polar oceans, with ice extent in the Northern Hemisphere ranging from approximately 7 x 10(exp 6) sq km in September to approximately 15 x 10(exp 6) sq km in March and ice extent in the Southern Hemisphere ranging from approximately 3 x 10(exp 6) sq km in February to approximately 18 x 10(exp 6) sq km in September. These ice covers have major impacts on the atmosphere, oceans, and ecosystems of the polar regions, and so as changes occur in them there are potential widespread consequences. Satellite data reveal considerable interannual variability in both polar sea ice covers, and many studies suggest possible connections between the ice and various oscillations within the climate system, such as the Arctic Oscillation, North Atlantic Oscillation, and Antarctic Oscillation, or Southern Annular Mode. Nonetheless, statistically significant long-term trends are also apparent, including overall trends of decreased ice coverage in the Arctic and increased ice coverage in the Antarctic from late 1978 through the end of 2003, with the Antarctic ice increases following marked decreases in the Antarctic ice during the 1970s. For a detailed picture of the seasonally varying ice cover at the start of the 21st century, this chapter includes ice concentration maps for each month of 2001 for both the Arctic and the Antarctic, as well as an overview of what the satellite record has revealed about the two polar ice covers from the 1970s through 2003.

  4. Mammals of the Sea.

    ERIC Educational Resources Information Center

    Naturescope, 1986

    1986-01-01

    Presents information on sea mammals, including definitions and characteristics of cetaceans, pinnipeds, and sirenians. Contains descriptions of the teaching activities "Whale Music,""Draw A Whale to Scale,""Adopt a Sea Mammal," and "Sea Mammal Sleuths." (TW)

  5. Melting Ice, Rising Seas

    NASA Video Gallery

    Sea level rise is an indicator that our planet is warming. Much of the world's population lives on or near the coast, and rising seas are something worth watching. Sea level can rise for two reason...

  6. Vesicomyinae (Bivalvia: Vesicomyidae) of the Kuril-Kamchatka Trench and adjacent abyssal regions

    NASA Astrophysics Data System (ADS)

    Krylova, Elena M.; Kamenev, Gennady M.; Vladychenskaya, Irina P.; Petrov, Nikolai B.

    2015-01-01

    Representatives of the subfamily Vesicomyinae (Bivalvia, Vesicomyidae) are tiny deep-sea molluscs distributed worldwide and reaching huge abundances of hundreds and thousands of specimens in trawl catches. During the German-Russian deep-sea expedition KuramBio (R/V Sonne, 2012) for the first time two vesicomyin species were collected from the abyssal plain adjacent to the Kuril-Kamchatka Trench from the depths of 4861-5787 m, Vesicomya pacifica (Smith, 1885) and "Vesicomya" filatovae sp.n. Two species of vesicomyins, V. sergeeviFilatova, 1971 and V. profundiFilatova, 1971, which were previously reported from the hadal of the Kuril-Kamchatka Trench, were not collected at the abyssal depth despite of the close geographical proximity of the sampling area to their distribution ranges. Altogether nine species of vesicomyins are recorded now from the West and Indo-West Pacific; data on distribution and morpho-anatomical characters of these species are provided. Taxonomic description of V. pacifica is revised including information on its soft part anatomy, new localities and COI sequences. For the first time for a vesicomyin bivalve molecular data is given for a species with an explicit morphological description and unambiguous taxonomic affiliation. Molecular analysis of 160 published COI sequences of vesicomyids and newly obtained molecular data on V. pacifica showed that V. pacifica and two undescribed vesicomyin species forming a monophyletic clade which exhibits sister relationships with the Pliocardiinae, the group of chemosymbiotic vesicomyids. "Vesicomya" filatovae sp.n. is provisionally assigned to the genus Vesicomya (s.l.) until additional morphological and molecular data are obtained. It differs from Vesicomya s.s. by a broader hinge margin with more radiating teeth and the presence of only one pair of demibranchs.

  7. Image registration using a weighted region adjacency graph

    NASA Astrophysics Data System (ADS)

    Al-Hasan, Muhannad; Fisher, Mark

    2005-04-01

    Image registration is an important problem for image processing and computer vision with many proposed applications in medical image analysis.1, 2 Image registration techniques attempt to map corresponding features between two images. The problem is particularly difficult as anatomy is subject to elastic deformations. This paper considers this problem in the context of graph matching. Firstly, weighted Region Adjacency Graphs (RAGs) are constructed from each image using an approach based on watershed saliency. 3 The vertices of the RAG represent salient regions in the image and the (weighted) edges represent the relationship (bonding) between each region. Correspondences between images are then determined using a weighted graph matching method. Graph matching is considered to be one of the most complex problems in computer vision, due to its combinatorial nature. Our approach uses a multi-spectral technique to graph matching first proposed by Umeyama4 to find an approximate solution to the weighted graph matching problem (WGMP) based on the singular value decomposition of the adjacency matrix. Results show the technique is successful in co-registering 2-D MRI images and the method could be useful in co-registering 3-D volumetric data (e.g. CT, MRI, SPECT, PET etc.).

  8. Stress Wave Interaction Between Two Adjacent Blast Holes

    NASA Astrophysics Data System (ADS)

    Yi, Changping; Johansson, Daniel; Nyberg, Ulf; Beyglou, Ali

    2016-05-01

    Rock fragmentation by blasting is determined by the level and state of stress in the rock mass subjected to blasting. With the application of electronic detonators, some researchers stated that it is possible to achieve improved fragmentation through stress wave superposition with very short delay times. This hypothesis was studied through theoretical analysis in the paper. First, the stress in rock mass induced by a single-hole shot was analyzed with the assumptions of infinite velocity of detonation and infinite charge length. Based on the stress analysis of a single-hole shot, the stress history and tensile stress distribution between two adjacent holes were presented for cases of simultaneous initiation and 1 ms delayed initiation via stress superposition. The results indicated that the stress wave interaction is local around the collision point. Then, the tensile stress distribution at the extended line of two adjacent blast holes was analyzed for a case of 2 ms delay. The analytical results showed that the tensile stress on the extended line increases due to the stress wave superposition under the assumption that the influence of neighboring blast hole on the stress wave propagation can be neglected. However, the numerical results indicated that this assumption is unreasonable and yields contrary results. The feasibility of improving fragmentation via stress wave interaction with precise initiation was also discussed. The analysis in this paper does not support that the interaction of stress waves improves the fragmentation.

  9. Adjacent flaps for lower lip reconstruction after mucocele resection.

    PubMed

    Ying, Binbin

    2012-03-01

    Mucocele forms because of salivary gland mucous extravasation or retention and is usually related to trauma in the area of the lower lip. It is a common benign lesion in the oral region. Although there are many conservative treatments such as the creation of a pouch (marsupialization), freezing (cryosurgery), micromarsupialization, and CO2 laser vaporization, surgical resection is the most commonly used means. Generally speaking, an elliptic incision was made to fully enucleate the lesion along with the overlying mucosa and the affected glands, then direct suturing is adequate. However, in some cases, direct suturing could cause lower lip deformity, and adjacent flaps for lower lip reconstruction after mucocele resection might be quite necessary. Based on our experience, adjacent mucosal flaps could be used when lesions were close to or even break through the vermilion border or their diameters were much more than 1 cm. A-T advancement flaps and transposition flaps were the mostly applied ones. Follow-up showed that all patients realized primary healing after 1 week postoperatively with satisfactory lower lip appearance, and there was no sign of increasing incidence of relapse. PMID:22421867

  10. Historical volcanoes of Armenia and adjacent areas: What is revisited?

    NASA Astrophysics Data System (ADS)

    Karakhanian, A.; Jrbashyan, R.; Trifonov, V.; Philip, H.; Arakelian, S.; Avagyan, A.; Baghdassaryan, H.; Davtian, V.

    2006-07-01

    The validity of some data in Karakhanian et al. [Karakhanian, A., Djrbashian, R., Trifonov V., Philip H., Arakelian S., Avagian, A., 2002. Holocene-historical volcanism and active faults as natural risk factor for Armenia and adjacent countries. Journal of Volcanology and Geothermal Research, 113, 1, 319-344; Karakhanian, A., Jrbashyan, R., Trifonov, V., Philip, H., Arakelian, S., Avagyan, A., Baghdassaryan, H., Davtian, V., Ghoukassyan, Yu., 2003. Volcanic hazards in the region of the Armenian nuclear power plant. Journal of Volcanology and Geothermal Research, 126/1-2, 31-62] that are revisited by R. Haroutiunian is considered. A conclusion is made that the revisions suggested by Haroutiunian concern unessential parts of the content of work by Karakhanian et al. [Karakhanian, A., Djrbashian, R., Trifonov V., Philip H., Arakelian S., Avagian, A., 2002. Holocene-historical volcanism and active faults as natural risk factor for Armenia and adjacent countries. Journal of Volcanology and Geothermal Research, 113, 1, 319-344; Karakhanian, A., Jrbashyan, R., Trifonov, V., Philip, H., Arakelian, S., Avagyan, A., Baghdassaryan, H., Davtian, V., Ghoukassyan, Yu., 2003. Volcanic hazards in the region of the Armenian nuclear power plant. Journal of Volcanology and Geothermal Research, 126/1-2, 31-62]. This article presents new evidence and re-proves the earlier conclusions that are disputed or revised by R. Haroutiunian.

  11. A numerical study of the barotropic tides and tidal energy distribution in the Indonesian seas with the assimilated finite volume coastal ocean model

    NASA Astrophysics Data System (ADS)

    Ding, Yang; Bao, Xianwen; Yu, Huaming; Kuang, Liang

    2012-04-01

    The tides and tidal energetics in the Indonesian seas are simulated using a three-dimensional finite volume coastal ocean model. The high-resolution coastline-fitted model is configured to better resolve the hydrodynamic processes around the numerous barrier islands. A large model domain is adopted to minimize the uncertainty adjacent to open boundaries. The model results with elevation assimilation based on a simple nudge scheme faithfully reproduced the general features of the barotropic tides in the Indonesian Seas. The mean root-mean-square errors between the observed and simulated tidal constants are 2.3, 1.1, 2.4, and 1.5 cm for M2, S2, K1, and O1, respectively. Analysis of the model solutions indicates that the semidiurnal tides in the Indonesian Seas are primarily dominated by the Indian Ocean, whereas the diurnal tides in this region are mainly influenced by the Pacific Ocean, which is consistent with previous studies. Examinations of tidal energy transport reveal that the tidal energy for both of the simulated tidal constituents are transported from the Indian Ocean into the IS mainly through the Lombok Strait and the Timor Sea, whereas only M2 energy enters the Banda Sea and continues northward. The tidal energy dissipates the most in the passages on both sides of Timor Island, with the maximum M2 and K1 tidal energy transport reaching about 750 and 650 kW m-1, respectively. The total energy losses of the four dominant constituents in the IS are nearly 338 GW, with the M2 constituent dissipating 240.8 GW. It is also shown that the bottom dissipation rate for the M2 tide is about 1-2 order of magnitudes larger than that of the other three tidal components in the Indonesian seas.

  12. 75 FR 68726 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Ocean Perch in the Bering Sea...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-09

    ...NMFS is opening directed fishing for Pacific ocean perch in the Bering Sea subarea of the Bering Sea and Aleutian Islands management area. This action is necessary to fully use the 2010 total allowable catch of Pacific ocean perch specified for the Bering Sea subarea of the Bering Sea and Aleutian Islands management...

  13. Sources of polyfluoroalkyl compounds in the North Sea, Baltic Sea and Norwegian Sea: Evidence from their spatial distribution in surface water.

    PubMed

    Ahrens, Lutz; Gerwinski, Wolfgang; Theobald, Norbert; Ebinghaus, Ralf

    2010-02-01

    The spatial distribution of 15 polyfluoroalkyl compounds (PFCs) in surface water was investigated in the North Sea, Baltic Sea and Norwegian Sea. In addition, an interlaboratory comparison of the sampling techniques and analysis was conducted. Highest concentration in the North Sea was found near the coast, whereas the summation operatorPFC concentration decreased rapidly from 18.4 to 0.07 ng l(-1) towards the open North Sea. The river Elbe could identify as a local input source for PFCs into the North Sea, whereas perfluorobutanoic acid (PFBA) was transported into the sampling area with the easterly current. In contrast to the North Sea, the distribution of PFCs in the Baltic Sea was relatively homogenous, where diffuse sources dominated. In general, the composition profile was influenced from local sources caused by human activities, whereas atmospheric depositions of here analysed PFCs were negligible, but it could have possibly an influence on low contaminated sites like the open North Sea or Norwegian Sea. PMID:19818459

  14. Late Quaternary history of the southwestern St. Lawrence Lowlands and adjacent Adirondack Highlands

    SciTech Connect

    Pair, D.L. . Dept. of Geology)

    1993-03-01

    The reconstruction of Late Wisconsinan ice retreat, proglacial lakes, and Champlain Sea history from the northwest Adirondack slope and adjacent St. Lawrence Lowlands is critical to the synthesis of a regional picture of deglacial events in the eastern Great Lakes region. Unfortunately, these same areas are well known for their limited exposures, landforms covered by thick forest, large tracts of land inaccessible to detailed field mapping, and the overall paucity of glacial materials preserved on upland surfaces. Despite these limitations, a model which utilizes multiple and field-truthed evidence has been used to designate areas where ice border deposits indicate a substantial recessional position. It employs the following criteria in this analysis: sedimentology and morphostratigraphy of morainal landform segments and related sediments; orientation and continuity of ice border drainage channels; and the relationship of ice borders and drainage systems to well documented local and regional water bodies which accompanied ice retreat. The results of this approach have provided a unique regional picture of deglaciation. Despite the inherent limitations of working in upland areas to reconstruct glacial events, detailed morphostratigraphic correlations based on multiple lines of evidence can yield important information. The positions of five former ice borders have been reconstructed from the available data. These ice margins correspond closely with those documented previously by others adjoining areas. This type of study, utilizing multiple and field-truthed lines of evidence, constitutes a tangible step towards understanding the nature and history of ice retreat along this portion of the Laurentide Ice Sheet.

  15. Downscaling ocean conditions with application to the Gulf of Maine, Scotian Shelf and adjacent deep ocean

    NASA Astrophysics Data System (ADS)

    Katavouta, Anna; Thompson, Keith R.

    2016-08-01

    The overall goal is to downscale ocean conditions predicted by an existing global prediction system and evaluate the results using observations from the Gulf of Maine, Scotian Shelf and adjacent deep ocean. The first step is to develop a one-way nested regional model and evaluate its predictions using observations from multiple sources including satellite-borne sensors of surface temperature and sea level, CTDs, Argo floats and moored current meters. It is shown that the regional model predicts more realistic fields than the global system on the shelf because it has higher resolution and includes tides that are absent from the global system. However, in deep water the regional model misplaces deep ocean eddies and meanders associated with the Gulf Stream. This is not because the regional model's dynamics are flawed but rather is the result of internally generated variability in deep water that leads to decoupling of the regional model from the global system. To overcome this problem, the next step is to spectrally nudge the regional model to the large scales (length scales > 90 km) of the global system. It is shown this leads to more realistic predictions off the shelf. Wavenumber spectra show that even though spectral nudging constrains the large scales, it does not suppress the variability on small scales; on the contrary, it favours the formation of eddies with length scales below the cutoff wavelength of the spectral nudging.

  16. Sea Searcher's Handbook: Activities from the Monterey Bay Aquarium.

    ERIC Educational Resources Information Center

    Monterey Bay Aquarium Foundation, Monterey, CA.

    The activities in this book guide exploration of rocky shores, wetlands, sandy shores, kelp forests, the open sea and deep sea, and introduce students to a variety of topics and different approaches. This material is written by marine educators and was tested with over 70,000 children visiting the Monterey Bay Aquarium (California) each year. The…

  17. Two wind-driven modes of winter sea ice variability in the Barents Sea

    NASA Astrophysics Data System (ADS)

    Herbaut, Christophe; Houssais, Marie-Noëlle; Close, Sally; Blaizot, Anne-Cécile

    2015-12-01

    The interannual variability of the winter sea ice area in the Barents Sea is investigated using SMMR-SSM/I data and a coupled ocean-sea ice model over the period 1979-2012. Our analysis reveals that the sea ice area in the northern and eastern parts of the Barents Sea do not covary. This contrast in behavior allows us to associate two distinct modes of variability with these two regions, with the variability of the overall Barents Sea ice cover being predominantly captured by the northern mode. Both modes show a dominant, near in-phase response to the surface wind, both being associated with different spatial patterns. The northern mode emerges in response to northwesterly wind anomalies which favor the export of ice and surface polar water from the Arctic between Svalbard and Franz Josef Land. Atlantic Water temperature anomalies, formed concomitantly with northerly wind anomalies in the vicinity of the Barents Sea Opening, also influence the northern mode in the following winter. These temperature anomalies are linked to local convergence of the oceanic heat transport. The delayed influence of the ocean on the sea ice is found primarily in the northeastern Barents Sea and occurs through the re-emergence of the Atlantic water temperature anomalies at the surface in the following fall and winter. An ocean-to-atmosphere feedback initiated by October SST anomalies in the central Barents Sea is further identified. This feedback is hypothesized to enhance the sea ice response in the northern Barents Sea by promoting the formation of meridional wind anomalies. In contrast, the eastern mode of variability of the Barents Sea ice mainly responds to wind anomalies with a strong zonal component, and is less influenced by the Atlantic Water temperature variability than the northern mode. While our results clearly highlight a role of the ocean in the Barents Sea ice variability, this role appears to be more spatially restricted following the sudden northward retreat of the ice

  18. Impact of Sea Spray on Air-Sea Fluxes

    NASA Astrophysics Data System (ADS)

    Veron, Fabrice; Mueller, James

    2013-11-01

    The contributions of sea spray drops to the total air-sea exchanges of momentum, heat, and mass remain an open question. A number of factors obscure any simple quantification of their contribution: the number of drops formed at the ocean surface and the per-drop contribution to the fluxes. To estimate these per-droplet fluxes, we present results from a large number of drop trajectories, which are simulated with a recently developed Lagrangian Stochastic model adapted for the heavy drop transport and evaporation within the marine boundary layer. Then, using commonly accepted spray generation functions we present estimates of spray fluxes which account for the mediating feedback effects from the droplets on the atmosphere. The results suggest that common simplifications in previous sea spray models, such as the residence time in the marine boundary layer, may not be appropriate. We further show that the spray fluxes may be especially sensitive to the size distribution of the drops. The total effective air-sea fluxes lead to drag and enthalpy coefficients that increase modestly with wind speed. The rate of increase for the drag coefficient is greatest at moderate wind speeds, while the rate of increase for the enthalpy coefficient is greatest at higher wind speeds. Funded by grants OCE-0850663 and OCE-0748767 from the National Science Foundation.

  19. Air bubble-shock wave interaction adjacent to gelantine surface

    NASA Astrophysics Data System (ADS)

    Lush, P. A.; Tomita, Y.; Onodera, O.; Takayama, K.; Sanada, N.; Kuwahara, M.; Ioritani, N.; Kitayama, O.

    1990-07-01

    The interaction between a shock wave and an air bubble-adjacent to a gelatine surface is investigated in order to simulate human tissue damage resulting from extracorporeal shock wave lithotripsy. Using high speed cine photography it is found that a shock wave of strength 11 MPa causes 1-3 mm diameter bubbles to produce high velocity microjets with penetration rates of approximately 110 m/s and penetration depths approximately equal to twice the initial bubble diameter. Theoretical considerations for liquid impact on soft solid of similar density indicate that microjet velocities will be twice the penetration rate, i.e. 220 m/s in the present case. Such events are the probable cause of observed renal tissue damage.

  20. An engineered dimeric protein pore that spans adjacent lipid bilayers

    PubMed Central

    Mantri, Shiksha; Sapra, K. Tanuj; Cheley, Stephen; Sharp, Thomas H.; Bayley, Hagan

    2013-01-01

    The bottom-up construction of artificial tissues is an underexplored area of synthetic biology. An important challenge is communication between constituent compartments of the engineered tissue and between the engineered tissue and additional compartments, including extracellular fluids, further engineered tissue and living cells. Here we present a dimeric transmembrane pore that can span two adjacent lipid bilayers and thereby allow aqueous compartments to communicate. Two heptameric staphylococcal α-hemolysin (αHL) pores were covalently linked in an aligned cap-to-cap orientation. The structure of the dimer, (α7)2, was confirmed by biochemical analysis, transmission electron microscopy (TEM) and single-channel electrical recording. We show that one of two β barrels of (α7)2 can insert into the lipid bilayer of a small unilamellar vesicle, while the other spans a planar lipid bilayer. (α7)2 pores spanning two bilayers were also observed by TEM. PMID:23591892

  1. 38. METAL WORKING TOOLS AND MACHINES ADJACENT TO THE CIRCA ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    38. METAL WORKING TOOLS AND MACHINES ADJACENT TO THE CIRCA 1900 MICHIGAN MACHINERY MFG. CO. PUNCH PRESS NEAR THE CENTER OF THE FACTORY BUILDING. AT THE LEFT FOREGROUND IS A MOVABLE TIRE BENDER FOR SHAPING ELI WINDMILL WHEEL RIMS. AT THE CENTER IS A FLOOR-MOUNTED CIRCA 1900 SNAG GRINDER OF THE TYPE USED FOR SMOOTHING ROUGH CASTINGS. ON THE WHEELED WORK STATION IS A SUNNEN BUSHING GRINDER, BEHIND WHICH IS A TRIPOD CHAIN VICE. IN THE CENTER BACKGROUND IS A WOODEN CHEST OF DRAWERS WHICH CONTAINS A 'RAG DRAWER' STILL FILLED WITH CLOTH RAGS PLACED IN THE FACTORY BUILDING AT THE INSISTENCE OF LOUISE (MRS. ARTHUR) KREGEL FOR THE CONVENIENCE AND CLEANLINESS OF WORKERS. IN THE LEFT BACKGROUND IS A CIRCA 1900 CROSS-CUTOFF CIRCULAR SAW. - Kregel Windmill Company Factory, 1416 Central Avenue, Nebraska City, Otoe County, NE

  2. Preventing Proximal Adjacent Level Kyphosis With Strap Stabilization.

    PubMed

    Zaghloul, Khaled M; Matoian, Brett J; Denardin, Nicholas B; Patel, Vikas V

    2016-07-01

    A substantial proportion of patients develop proximal junctional kyphosis following spinal surgery. To combat this postoperative change, several techniques have focused on maintaining the structural integrity of adjacent spinal levels and adapting the proximal end of the fusion construct to accommodate the increased mechanical stressors produced by long spinal fusion. The use of Mersilene tape (Ethicon, Somerville, New Jersey) for spine and orthopedic surgery is well documented, although considerably less is known about its use for preventing proximal junctional kyphosis. This article describes a proposed technique using Mersilene tape to provide a check-rein strap stabilization at the proximal end of fusion constructs. Initial data suggest that use of this technique may prevent formation of proximal junctional kyphosis. [Orthopedics. 2016; 39(4):e794-e799.]. PMID:27158827

  3. Laser ablation of human atherosclerotic plaque without adjacent tissue injury

    NASA Technical Reports Server (NTRS)

    Grundfest, W. S.; Litvack, F.; Forrester, J. S.; Goldenberg, T.; Swan, H. J. C.

    1985-01-01

    Seventy samples of human cadaver atherosclerotic aorta were irradiated in vitro using a 308 nm xenon chloride excimer laser. Energy per pulse, pulse duration and frequency were varied. For comparison, 60 segments were also irradiated with an argon ion and an Nd:YAG laser operated in the continuous mode. Tissue was fixed in formalin, sectioned and examined microscopically. The Nd:YAG and argon ion-irradiated tissue exhibited a central crater with irregular edges and concentric zones of thermal and blast injury. In contrast, the excimer laser-irradiated tissue had narrow deep incisions with minimal or no thermal injury. These preliminary experiments indicate that the excimer laser vaporizes tissue in a manner different from that of the continuous wave Nd:YAG or argon ion laser. The sharp incision margins and minimal damage to adjacent normal tissue suggest that the excimer laser is more desirable for general surgical and intravascular uses than are the conventionally used medical lasers.

  4. Geomorphology of portions of western Kentucky and adjacent areas

    SciTech Connect

    Dilamarter, R.C.

    1982-07-01

    The geomorphology of portions of western Kentucky and adjacent areas in Indiana, Illinois and Tennessee is presented as a background for interpreters evaluating the present land surface using remotely sensed imagery. Eight physiographic units were analyzed and are briefly discussed with reference to topography and surface deposits. Great diversity was found to be characteristic of the region, the result of different structural influences and geomorphic processes. The landscape bears the marks of fluvial, glacial, eolian, lacustrine and karstic environments, so a regional geomorphic history was compiled from the literature as an aid to understanding the land surface. Three smaller zones in Kentucky were analyzed in greater detail regarding topography and geomorphic development because of their potential importance in subsurface exploration.

  5. GOAT ROCKS WILDERNESS AND ADJACENT ROADLESS AREAS, WASHINGTON.

    USGS Publications Warehouse

    Church, S.E.; Close, T.J.

    1984-01-01

    The Goat Rocks Wilderness and adjacent roadless areas are a rugged, highly forested, scenic area located on the crest of the Cascade Range in south-central Washington. Several mineral claims have been staked in the area. Mineral surveys were conducted. Geochemical, geophysical, and geologic investigations indicate that three areas have probable mineral-resource potential for base metals in porphyry-type deposits. Available data are not adequate to permit definition of the potential for oil and gas. There is little likelihood for the occurrence of other kinds of energy resources in the area. Evaluation of resource potential in the three areas identified as having probable mineral-resource potential could be improved by more detailed geochemical studies and geologic mapping.

  6. Scolopendromorpha of New Guinea and adjacent islands (Myriapoda, Chilopoda).

    PubMed

    Schileyko, Arkady A; Stoev, Pavel E

    2016-01-01

    The centipede fauna of the second largest island in the world, New Guinea, and its adjacent islands, is poorly known, with most information deriving from the first half of the 20th century. Here we present new data on the order Scolopendromorpha based on material collected in the area in the last 40 years, mainly by Bulgarian and Latvian zoologists. The collections comprise eleven species of six genera and three families. The diagnosis of Cryptops (Trigonocryptops) is emended in the light of the recent findings. The old and doubtful record of Scolopendra multidens Newport, 1844 from New Guinea is referred to S. subspinipes Leach, 1815 and the species is here excluded from the present day list of New Guinean scolopendromorphs. Cryptops nepalensis Lewis, 1999 is here recorded from New Guinea for the first time. An annotated list and an identification key to the scolopendromorphs of the studied region are presented. PMID:27515618

  7. Increased apoptosis in gastric mucosa adjacent to intestinal metaplasia

    PubMed Central

    van Grieken, N C T; Meijer, G A; zur Hausen, A; Meuwissen, S G M; Baak, J P A; Kuipers, E J

    2003-01-01

    Background: The biological processes involved in the development of gastric mucosal atrophy and intestinal metaplasia are still incompletely understood. Reports testing the hypothesis that apoptosis leads to atrophy have yielded conflicting results. The availability of new antibodies for the detection of apoptotic cells in tissue sections has facilitated the analysis of the role of apoptosis in the gastritis–atrophy–intestinal metaplasia sequence. Methods: Archival material from 40 gastric resection specimens with normal mucosa (n = 5), chronic active gastritis (n = 17), or intestinal metaplasia (n = 18) was studied. Immunohistochemistry was performed using antibodies directed against cleaved cytokeratin 18 and active caspase 3. Slides were scored on a 0–3 scale for the presence of apoptotic cells. Results: Normal gastric mucosa contained low numbers of apoptotic cells at the surface epithelium (mean score, 0.20). This number was significantly increased in cases with chronic gastritis (mean score, 1.06) and in those with intestinal metaplasia (mean score, 2.56). Within the intestinal metaplasia cases, 44 different foci of intestinal metaplasia were identified. In 39 of these 44 areas, concentrations of apoptotic cells were seen immediately adjacent to the foci of intestinal metaplasia, but not in the metaplastic epithelium itself. Conclusions: Apoptosis is uncommon in normal gastric mucosa. Chronic inflammation and intestinal metaplasia are associated with increased apoptosis, but occur mainly at the mucosal surface and not in the deeper layers. These findings do not support the concept that apoptosis underlies the loss of gastric glands and leads to atrophy, but the observed concentration of apoptotic epithelial cells adjacent to foci of intestinal metaplasia could be related to heterogeneity of epithelial damage, causing apoptosis, to which intestinal metaplasia is a response. PMID:12719456

  8. Classical Hodgkin Lymphoma Arising Adjacent to a Breast Implant.

    PubMed

    Ryan, Ciara; Ged, Yasser; Quinn, Fiona; Walker, Jan; Kennedy, John; Gillham, Charles; Pittaluga, Stefania; McDermott, Ronan; Vandenberghe, Elisabeth; Grant, Cliona; Flavin, Richard

    2016-08-01

    Breast implant-associated lymphoma has recently gained wide recognition. Anaplastic large cell lymphoma (ALCL) is the most frequently diagnosed subtype in this setting but the spectrum is broadening. A 66-year-old woman developed swelling and itch around her saline implant 6 years after its insertion. Imaging revealed a fluid collection surrounding the implant with an adjacent mass. Microscopy showed sclerotic tissue punctuated by discrete cellular nodules comprising small lymphocytes, eosinophils and interspersed large atypical Hodgkin Reed-Sternberg (HRS)-like cells. The HRS-like cells stained positively for CD30 and CD15 by immunohistochemistry. Small T-lymphocytes formed rosettes around HRS-like cells. Appearances were consistent with classical Hodgkin lymphoma (HL). Multiplex polymerase chain reaction demonstrated no clonal rearrangements of immunoglobulin or T-cell receptor genes, however, a t(14;18)(q32;q21)BCL2-JH translocation involving the major breakpoint region of the bcl2 gene was present. Staging positron emission tomography-computed tomography scan revealed FDG-avid masses in the right axilla and pelvis. Subsequent pathological examination identified low-grade follicular lymphoma (FL) with a t(14;18) translocation at these sites. To our knowledge, this is the first case of HL arising adjacent to a breast implant. An awareness of this diagnosis is important as classical HL, with its prominent mixed inflammatory background, may be overlooked as a reactive process when histologically assessing capsulectomy specimens. It is also important in the differential diagnosis for implant-associated ALCL as both contain large atypical CD30-positive cells highlighting the need for full immunohistochemical and molecular workup in such cases. This case also adds to the large body of literature regarding the association between HL and FL. PMID:26888955

  9. Effect of Fluoridated Sealants on Adjacent Tooth Surfaces

    PubMed Central

    Cagetti, M.G.; Carta, G.; Cocco, F.; Sale, S.; Congiu, G.; Mura, A.; Strohmenger, L.; Lingström, P.; Campus, G.

    2014-01-01

    A double-blind randomized clinical trial was performed in 6- to 7-yr-old schoolchildren to evaluate, in a 30-mo period, whether the caries increment on the distal surface of the second primary molars adjacent to permanent first molars sealed with fluoride release compounds would be lower with respect to those adjacent to permanent first molars sealed with a nonfluoridated sealant. In sum, 2,776 subjects were enrolled and randomly divided into 3 groups receiving sealants on sound first molars: high-viscosity glass ionomer cement (GIC group); resin-based sealant with fluoride (fluoride-RB group); and a resin-based sealant without fluoride (RB group). Caries (D1 – D3 level) was recorded on the distal surface of the second primary molar, considered the unit of analysis including only sound surfaces at the baseline. At baseline, no differences in caries prevalence were recorded in the 3 groups regarding the considered surfaces. At follow-up, the prevalence of an affected unit of analysis was statistically lower (p = .03) in the GIC and fluoride-RB groups (p = .04). In the GIC group, fewer new caries were observed in the unit of analysis respect to the other 2 groups. Incidence rate ratios (IRRs) were 0.70 (95% confidence interval: 0.50, 0.68; p < .01) for GIC vs. RB and 0.79 (95% confidence interval: 0.53, 1.04; p = .005) for fluoride-RB vs. RB. Caries incidence was significantly associated with low socioeconomic status (IRR = 1.18; 95% confidence interval: 1.10, 1.42; p = .05). Dental sealant high-viscosity GIC and fluoride-RB demonstrated protection against dental caries, and there was evidence that these materials afforded additional protection for the tooth nearest to the sealed tooth (clinical trial registration NCT01588210). PMID:24846910

  10. Sea ice deformation and the ice thickness distribution: How novel observations can help to improve models

    NASA Astrophysics Data System (ADS)

    Martin, T.

    2012-12-01

    Several decades of Arctic-wide observational records of sea ice concentration and drift offer great opportunities to validate the sea ice component of global climate models (GCMs). Recent advancements in air- and space-borne ice thickness retrieval add the long missed "3rd dimension" to these observations. However, in order to understand why a model diverges from observations, why the model physics may be inadequate and how to improve these, often observations with great detail rather than great coverage are desired. From a modeler's perspective an ideal set of observations offers the opportunity to build parameterizations directly upon prognostic model variables, such as sea ice concentration, thickness and drift. However, the dependency on prognostic variables is not a guaranty yet that a parameterization is flexible enough to cope with the rapid changes currently observed in the Arctic. In particular in sea ice modeling there is a need to revisit parameters and parameterizations dating back to the 1970s to make sure they are still valid. Examples relating to sea ice mechanics are drag coefficients, sea ice strength, and deformation. The latter importantly shapes the ice thickness distribution (ITD) by ridging thin into thick ice thereby compacting the ice cover, which opens up leads. Leads in the pack ice act like windows in a solid wall: they enable a direct, enhanced exchange between ocean and atmosphere. Most sea ice models used in GCMs consider an ITD for the computation of the conductive heat flux only in an idealized statistical manner. Currently, few models consider the effect of sea ice mechanics on the ITD, i.e. advection and deformation. The ITD has lately gained greater attention because advances in both models and observations enable higher spatial resolution furthering the perception that changes in Arctic sea ice characteristics go along with changing ice types. In this presentation simulations with a GCM are used to demonstrate the impact of a

  11. Features of Red Sea Water Masses

    NASA Astrophysics Data System (ADS)

    Kartadikaria, Aditya; Hoteit, Ibrahim

    2015-04-01

    Features of Red Sea water mass can be divided into three types but best to be grouped into two different classes that are split at the potential density line σθ=27.4. The surface water (0-50 m) and the intermediate water (50-200 m) have nearly identical types of water mass. They appear as a maxima salinity layer for the water mass that has σθ > 26.0, and as a minimum salinity layer for water mass that has σθ < 26.0. These types of water masses are strongly affected by mixing that is controlled by seasonal variability, fresh water intrusion of the Gulf of Aden Intermediate Water (GAIW), and eddies variability. Two types of mixing; isopycnal and diapycnal mixing are part of important physical phenomena that explain the change of water mass in the Red Sea. The isopycnal mixing occurs at the neutral potential density line, connecting the Red Sea with its adjacent channel, the Gulf of Aden. Diapycnal mixing is found as a dominant mixing mode in the surface of the Red Sea Water and mainly due to energetic eddy activity. Density gradients, across which diapycnal mixing occurs, in the Red Sea are mainly due to large variations in salinity. The isolation of an extreme haline water mass below the thermocline contributes to the generation of the latitudinal shift and low diapycnal mixing. This finding further explains the difference of spatial kinetic mixing between the RSW and the Indian Ocean basin.

  12. Large-Scale Environmental Influences on the Onset, Maintenance, and Dissipation of Six Sea Fog Cases over the Yellow Sea

    NASA Astrophysics Data System (ADS)

    Li, Pengyuan; Fu, Gang; Lu, Chungu

    2012-05-01

    Sea fog is typically formed and developed under a set of favorable environmental conditions, which are associated with the station pressure changes, sea level pressure, winds, temperature, water vapor supply, and sea surface temperature. Understanding of these environmental factors during the evolution of a sea fog episode is crucial for forecasting the occurrence and severity of sea fogs over the ocean and adjacent coastal areas. In this study, the large-scale environment variability of six fog events over the Yellow Sea was investigated. It was realized in the present study that the northwest Pacific Ocean high (NPH) is vital to fog formation over the Yellow Sea. In our study, six fog cases can be basically divided into two types: (1) pressure-weakening type, (2) pressure-strengthening type. The former type happened in spring and the latter type in summer. Prevailing southerly winds, accompanied with the well-positioned NPH, may supply a large amount of warm water vapor for the fog formation and maintenance. The intensity of the air temperature inversion is stronger in summer cases than that in spring ones. The wind direction change from south to north and the unstable lower atmosphere may lead to fog's dissipation. This study may provide a comprehensive understanding of sea fog's onset, maintenance, and dissipation over the Yellow Sea.

  13. Intrusion of radioactive industrially polluted water from North Sea into central Baltic Sea

    SciTech Connect

    Vakulovskiy, S.M.; Nikitin, A.I.

    1985-02-01

    The problem of penetration of radioactive industrially polluted water into the central Baltic Sea was studied. The content of Cs-134 as determined in water near the bottom of deep water trenches along the path traveled by North Sea water entering the Baltic. Samples were taken at 5 locations, with Cs-134 concentrated from samples of several thousands of liters. It was found that radioactive pollution caused by the entry of water from the North Sea extends through the system of deep water depressions into the Baltic as far as the Gotland trench. The greatest degree of contamination is found in the Arkona depression adjacent to the straits. The concentration of Cs-134 in the Gdansk trench is one-half as great and in the Gotland trench one-third as great as in the Arkona depression. Radioactive contamination in the Baltic is attributed to discharge of radioactive wastes by plants at Windscale.

  14. Cenozoic rift tectonics of the Japan Sea

    SciTech Connect

    Kimura, K.

    1988-08-01

    The Japan Sea is one of the back-arc basins in trench-arc systems bordering the western Pacific. Recent paleomagnetic works suggest the Japan Sea opened during early to middle Miocene. Radiometric and microfossil ages of the Cenozoic onland sequences in the Japanese Islands elucidate the rift tectonics of the Japan Sea. The rifting history is summarized as follows: nonmarine volcanic formations of prerift stage before 50 Ma, rift-onset unconformity at 40 Ma, nonmarine volcanic formations of synrift stage 20-33 Ma, breakup unconformity 19 Ma showing the opening of the Japan Sea, marine volcanic and sedimentary formations of synrift stage 14.5-18 Ma, beginning of regional subsidence 14.5 Ma corresponding to the end of the Japan Sea opening, marine sedimentary formations of postdrift stage after 14.5 Ma. Rifting is not limited to the synrift stage but is continued to the syndrift stage. Rifting led to a horst-and-graben structure. Thus, the Cenozoic onland sequences in the Japanese Islands are suited for a study of rift tectonics because the sequences were subaerially exposed by the late Miocene-Holocene island-arc tectonics. Rift tectonics cannot be studied as easily in most Atlantic-type passive margins.

  15. Adjacent Habitat Influence on Stink Bug (Hemiptera: Pentatomidae) Densities and the Associated Damage at Field Corn and Soybean Edges

    PubMed Central

    Venugopal, P. Dilip; Coffey, Peter L.; Dively, Galen P.; Lamp, William O.

    2014-01-01

    The local dispersal of polyphagous, mobile insects within agricultural systems impacts pest management. In the mid-Atlantic region of the United States, stink bugs, especially the invasive Halyomorpha halys (Stål 1855), contribute to economic losses across a range of cropping systems. Here, we characterized the density of stink bugs along the field edges of field corn and soybean at different study sites. Specifically, we examined the influence of adjacent managed and natural habitats on the density of stink bugs in corn and soybean fields at different distances along transects from the field edge. We also quantified damage to corn grain, and to soybean pods and seeds, and measured yield in relation to the observed stink bug densities at different distances from field edge. Highest density of stink bugs was limited to the edge of both corn and soybean fields. Fields adjacent to wooded, crop and building habitats harbored higher densities of stink bugs than those adjacent to open habitats. Damage to corn kernels and to soybean pods and seeds increased with stink bug density in plots and was highest at the field edges. Stink bug density was also negatively associated with yield per plant in soybean. The spatial pattern of stink bugs in both corn and soybeans, with significant edge effects, suggests the use of pest management strategies for crop placement in the landscape, as well as spatially targeted pest suppression within fields. PMID:25295593

  16. Colorful Underwater Sea Creatures

    ERIC Educational Resources Information Center

    McCutcheon, Heather

    2011-01-01

    In this article, the author describes a project wherein students created colorful underwater sea creatures. This project began with a discussion about underwater sea creatures and how they live. The first step was making the multi-colored tissue paper that would become sea creatures and seaweed. Once students had the shapes of their sea creatures…

  17. Raising the dead without a Red Sea-Dead Sea canal? Hydro-economics and governance

    NASA Astrophysics Data System (ADS)

    Rosenberg, D. E.

    2010-12-01

    Seven decades of extractions have dramatically reduced Jordan River flows, lowered the Dead Sea level, opened sink holes, and caused other environmental problems. The fix Jordan, Israel, and the Palestinians propose would build an expensive multipurpose canal from the Red Sea to the Dead Sea that would also generate hydropower and desalinated water. This paper compares the Red-Dead project to alternatives that may also raise the Dead Sea level. Hydro-economic model results for the Jordan-Israel-Palestinian inter-tied water systems show two restoration alternatives are more economically viable than the proposed Red-Dead project. Many decentralized new supply, wastewater reuse, conveyance, conservation, and leak reduction projects and programs in each country can together increase economic benefits and reliably deliver up to 900 MCM/year to the Dead Sea. Similarly, a smaller Red-Dead project that only generates hydropower can deliver large flows to the Dead Sea when the sale price of generated electricity is sufficiently high. However, for all restoration options, net benefits fall and water scarcity rises as flows to the Dead Sea increase. This finding suggests (i) each country has no individual incentive to return water to the Dead Sea, and (ii) outside institutions that seek to raise the Dead must also offer countries direct incentives to deliver water to the Sea besides building the countries new infrastructure.

  18. 33 CFR 110.140 - Buzzards Bay, Nantucket Sound, and adjacent waters, Mass.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., and adjacent waters, Mass. 110.140 Section 110.140 Navigation and Navigable Waters COAST GUARD..., Nantucket Sound, and adjacent waters, Mass. Link to an amendment published at 76 FR 35744, June 20, 2011. (a... adjacent waters, Mass. (a) * * * (2) Anchorage B. All waters bounded by a line beginning at 41°36′42.3″...

  19. 27 CFR 19.162 - Operations bond for distilled spirits plant and adjacent bonded wine cellar.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... distilled spirits plant and adjacent bonded wine cellar. 19.162 Section 19.162 Alcohol, Tobacco Products and... bond for distilled spirits plant and adjacent bonded wine cellar. (a) One bond satisfying two requirements. A proprietor who operates a bonded wine cellar that is adjacent to the proprietor's...

  20. Investigation of radar discrimination of sea ice

    NASA Technical Reports Server (NTRS)

    Parashar, S. K.; Biggs, A. W.; Fung, A. K.; Moore, R. K.

    1974-01-01

    The ability of radar to discriminate sea ice types and their thickness was studied. Radar backscatter measurements at 400 MHz (multi-polarization) and 13.3 GHz (VV polarization) obtained from NASA Earth Resources Aircraft Program Mission 126 were analyzed in detail. The scatterometer data were separated into seven categories of sea ice according to age and thickness as interpreted from stereo aerial photographs. The variations of radar backscatter cross-section with sea ice thickness at various angles are presented at the two frequencies. There is a reversal of angular character of radar return from sea ice less than 18 cm thick at the two frequencies. Multi-year ice (sea ice greater than 180 cm thick) gives strongest return at 13.3 GHz. First-year ice (30 cm to 90 cm thick) gives strongest return at 400 MHz. Open water can be differentiated at both the frequencies. Four-polarization 16.5 GHz radar imagery was also obtained. Open water and three categories of sea ice can be identified on the images. The results of the imagery analysis are consistent with the radar scatterometer results.

  1. Terrigenous Sedimentation Patterns at Reefs Adjacent to the Guanica Bay Watershed, Southwest Puerto Rico

    NASA Astrophysics Data System (ADS)

    Sherman, C.; Whitall, D.

    2014-12-01

    Guanica Bay is an estuary on the southwest coast of Puerto Rico with numerous nearshore reefs located in adjacent coastal waters. As part of the multi-agency Guanica Bay Watershed Project, a study was undertaken to establish baseline levels of terrigenous sedimentation reaching reefs adjacent to the Guanica Bay watershed as well as establish spatial and temporal patterns in its delivery. To characterize and quantify sedimentation patterns, sediment traps were established at nine reef sites occurring along an ~ 14 km stretch of coastline centered on the outlet of the bay. Sites were located at shallow reefs within 2 km of the shore at depths of ~ 10 m. Two additional sites were located at the mouth of the Rio Loco where it empties into Guanica Bay and at the mouth of the bay where it opens into adjacent coastal waters. Traps were collected monthly from August 2009 through July 2012 to determine both the amount of sediment accumulation (mg cm-2 day-1) and its composition. Composition is expressed in terms of relative amounts of calcium carbonate (in situ production), organic material and terrigenous material. Average trap accumulation rates among the reef sites ranged from ~ 3 to 28 mg cm-2 day-1. Average percent terrigenous material within reef accumulation ranged from ~ 20% to 30%. While trap accumulation rates are highly variable on both spatial and temporal scales, the composition of sediments and relative amount of terrigenous material is fairly uniform. Similar temporal patterns in accumulation rates among the sites without corresponding changes in composition of sediments point to resuspension of bottom sediments by wave action as a primary driver of sedimentary dynamics at these reefs. Sites closest to Guanica Bay display the highest degree of terrigenous influence in terms of trap accumulation rates and percent terrigenous material, which is consistent with Guanica Bay serving as a local source of terrigenous material to coastal waters. However, the lack of

  2. Beaufort Sea: information update

    SciTech Connect

    Becker, P.R.

    1988-04-01

    The report is based on a multi-disciplinary meeting held March 6-7, 1985, as part of preparations for the Beaufort Sea Sale 97. The chapters are based on presentations given: The causeway effect: Modification of nearshore thermal regime resulting from causeways; Summertime sea ice intrusions in the Chukchi Sea; The deepwater limit of ice gouging on the Beaufort Sea shelf; Distribution, abundance, migration, harvest, and stock identity of Belukha Whales in the Beaufort Sea; Ringed seals in the Beaufort Sea; Beaufort Sea socioeconomics; The Baffin Island Oil Spill, (BIOS) Project.

  3. Seasonal change of antarctic sea ice cover.

    PubMed

    Gordon, A L; Taylor, H W

    1975-01-31

    The winter expansion of the sea ice surrounding Antarctica and the subsequent retreat of the ice in summer may be linked with the wind stress acting on the Southern Ocean in conjunction with the heat exchange in open water regions within the ice fields. PMID:17814267

  4. Editorial: Eutrophication and hypoxia and their impacts on the ecosystem of the Changjiang Estuary and adjacent coastal environment

    NASA Astrophysics Data System (ADS)

    Zhang, Jing; Xiao, Tian; Huang, Daji; Liu, Su Mei; Fang, Jianguang

    2016-02-01

    The Changjiang (Yangtze River) Estuary plays an important role in the land-ocean interactions of East Asia, particularly in regard to the fate of land-derived materials and their impact on marine ecosystems in the Northwest Pacific Ocean. The 12 papers included in this special issue describe results from the MEcoPAM Study, an IMBER-China project, which occurred in 2011-2015. This project used a multi-disciplinary approach to understand ecosystem function of the Changjiang Estuary in response to multiple stressors (i.e. combined external forcings). The results presented here show that human activities in the watersheds have greatly changed the flux and variation of dissolved and particulate materials from the river. Further interactions between the Changjiang Watersheds and the East China Sea can dramatically modify the pathways of biogeochemistry and food web dynamics of the estuary and adjacent coastal environment at seasonal and inter-annual scales.

  5. Mercury speciation in the Adriatic Sea.

    PubMed

    Kotnik, Jože; Horvat, Milena; Ogrinc, Nives; Fajon, Vesna; Žagar, Dušan; Cossa, Daniel; Sprovieri, Francesca; Pirrone, Nicola

    2015-07-15

    Mercury and its speciation were studied in surface and deep waters of the Adriatic Sea. Several mercury species (i.e. DGM – dissolved gaseous Hg, RHg – reactive Hg, THg – total Hg, MeHg – monomethyl Hg and DMeHg – dimethylmercury) together with other water parameters were measured in coastal and open sea deep water profiles. THg concentrations in the water column, as well as in sediments and pore waters, were the highest in the northern, most polluted part of the Adriatic Sea as the consequence of Hg mining in Idrija and the heavy industry of northern Italy. Certain profiles in the South Adriatic Pit exhibit an increase of DGM just over the bottom due to its diffusion from sediment as a consequence of microbial and/or tectonic activity. Furthermore, a Hg mass balance for the Adriatic Sea was calculated based on measurements and literature data. PMID:26013591

  6. FAST OPENING SWITCH

    DOEpatents

    Bender, M.; Bennett, F.K.; Kuckes, A.F.

    1963-09-17

    A fast-acting electric switch is described for rapidly opening a circuit carrying large amounts of electrical power. A thin, conducting foil bridges a gap in this circuit and means are provided for producing a magnetic field and eddy currents in the foil, whereby the foil is rapidly broken to open the circuit across the gap. Advantageously the foil has a hole forming two narrow portions in the foil and the means producing the magnetic field and eddy currents comprises an annular coil having its annulus coaxial with the hole in the foil and turns adjacent the narrow portions of the foil. An electrical current flows through the coil to produce the magnetic field and eddy currents in the foil. (AEC)

  7. Cas9 Functionally Opens Chromatin.

    PubMed

    Barkal, Amira A; Srinivasan, Sharanya; Hashimoto, Tatsunori; Gifford, David K; Sherwood, Richard I

    2016-01-01

    Using a nuclease-dead Cas9 mutant, we show that Cas9 reproducibly induces chromatin accessibility at previously inaccessible genomic loci. Cas9 chromatin opening is sufficient to enable adjacent binding and transcriptional activation by the settler transcription factor retinoic acid receptor at previously unbound motifs. Thus, we demonstrate a new use for Cas9 in increasing surrounding chromatin accessibility to alter local transcription factor binding. PMID:27031353

  8. Cas9 Functionally Opens Chromatin

    PubMed Central

    Barkal, Amira A.; Srinivasan, Sharanya; Hashimoto, Tatsunori; Gifford, David K.; Sherwood, Richard I.

    2016-01-01

    Using a nuclease-dead Cas9 mutant, we show that Cas9 reproducibly induces chromatin accessibility at previously inaccessible genomic loci. Cas9 chromatin opening is sufficient to enable adjacent binding and transcriptional activation by the settler transcription factor retinoic acid receptor at previously unbound motifs. Thus, we demonstrate a new use for Cas9 in increasing surrounding chromatin accessibility to alter local transcription factor binding. PMID:27031353

  9. Concentrations, size-distributions and air-to-sea fluxes of bio-active trace elements on the New Jersey coast

    NASA Astrophysics Data System (ADS)

    Gao, Y.; Xu, G.; Xu, T.; Mukherjee, P.

    2014-12-01

    The coastal marine atmosphere adjacent to large urban and industrial centers can be strongly impacted by pollution emissions, resulting in high loading of pollutants in the ambient air. Among airborne substances are certain bioactive trace elements including Cd, Cu, and Zn from a variety of emission sources. High concentrations of these elements in coastal air could not only result in enhanced air-to-sea deposition fluxes to coastal waters, but they could also be transported over the open ocean, affecting the composition of the remote marine atmosphere. In this presentation, we will discuss the concentrations, particle-size distributions of selected trace elements in aerosols and their properties in precipitation observed on the New Jersey coast. The estimates of the air-to-water deposition fluxes of these elements will also be discussed.

  10. Past and present Aral Sea

    NASA Astrophysics Data System (ADS)

    Dukhovniy, Viktor; Stulina, Galina; Eshchanov, Odylbek

    2013-04-01

    organized in 2005-2009 sixth expeditions for complex remote sensing and ground investigations Aral Sea former bottom that were complemented in 2010 -2011 by two expeditions with GFZ. As a result, the landscape, soils and environment mapping was done with determination of ecologically unstable zones and assessment total change of lands situation compared with the pre-independence time. Moreover - methodic of monitoring water, environment and hydro geological indicators on the all deltas area was elaborated, organized its testing and combined with remote sensing data on Amudarya delta for 2009-2012. It permits to SIC ICWC to organize systematic permanent (decadal) monitoring and recording of size, volume and level of water in Aral Sea. Since the beginning of regular observations over the Aral Sea level, 2 periods can be emphasized: 1. Conditionally natural period - 1911-1960 - characterized by a relatively stable hydrological regime, with fluctuations in the level around 53 m and the range of inter-annual fluctuations at no more than 1 m., when the sea received annually about a half of the run-off in the Syrdarya and Amudarya Rivers, i.e. 50-60 km3/yr. 2. Intensive anthropogenic impact period - since the 1960s, a vast extension of irrigable land was carried out in Central Asia that resulted in intensive diversion of river run-off. Since then, the sea level has been falling steadily, causing a dramatic reduction in the water surface area, a decrease in water volume and depths, great changes in shoreline configuration and an expansion of the desert areas adjacent to the Aral Sea. From 1960-1985, when the sea was an integral water body, slight lowering in the sea level took place until the 1970s, when the sea-level decreased with the mean level lowering 1 m. The desiccation process accelerated visibly from the mid 1970s. In 1975-1980, the level decreased by 0.65 m a year on average. Moreover, the level dropped greatly, when the run-off of the Amudarya did not reach the Aral Sea

  11. Benthic polychaete diversity patterns and community structure in the Whittard Canyon system and adjacent slope (NE Atlantic)

    NASA Astrophysics Data System (ADS)

    Gunton, Laetitia M.; Neal, Lenka; Gooday, Andrew J.; Bett, Brian J.; Glover, Adrian G.

    2015-12-01

    We examined deep-sea macrofaunal polychaete species assemblage composition, diversity and turnover in the Whittard Canyon system (NE Atlantic) using replicate megacore samples from three of the canyon branches and one site on the continental slope to the west of the canyon, all at ~3500 m water depth. A total of 110 polychaete species were recorded. Paramphinome jeffreysii was the most abundant species (2326 ind. m-2) followed by Aurospio sp. B (646 ind. m-2), Opheliidae sp. A (393 ind. m-2), Prionospio sp. I (380 ind. m-2), and Ophelina abranchiata (227 ind. m-2). Species composition varied significantly across all sites. From west to east, the dominance of Paramphinome jeffreysii increased from 12.9% on the slope to 39.6% in the Eastern branch. Ordination of species composition revealed that the Central and Eastern branches were most similar, whereas the Western branch and slope sites were more distinct. High abundances of P. jeffreysii and Opheliidae sp. A characterised the Eastern branch of the canyon and may indicate an opportunistic response to a possible recent input of organic matter inside the canyon. Species richness and diversity indices were higher on the slope compared with inside the canyon, and the slope site had higher species evenness. Within the canyon, species diversity between branches was broadly similar. Despite depressed diversity within the canyon compared with the adjacent slope, the fact that 46 of the 99 polychaete species found in the Whittard Canyon were not present on the adjacent slope suggests that this feature may enhance the regional species pool. However, our sampling effort on the adjacent slope was insufficient to confirm this conclusion.

  12. Paleoenvironments and hydrocarbon potential of Upper Jurassic Norphlet Formation of southwestern Alabama and adjacent coastal water area

    SciTech Connect

    Mancini, E.A.; Mink, R.M.; Bearden, B.L.

    1984-09-01

    Upper Jurassic Norphlet sediments in southwestern Alabama and the adjacent coastal water area accumulated under arid climatic conditions. The Appalachian Mountains of the eastern United States extended into southwestern Alabama, providing a barrier for air and water circulation during Norphlet deposition. Norphlet paleogeography was dominated by a broad desert plain rimmed to the north and east by the Appalachians and to the south by a developing shallow sea. Initiation of Norphlet sedimentation was a result of erosion of the southern Appalachians. Norphlet conglomerates were deposited in coalescing alluvial fans in proximity to an Appalachian source. The conglomeratic sandstones grade downdip into red-bed lithofacies that accumulated in distal portions of alluvial fan and wadi systems. Quartzose sandstones (Denkman Member) were deposited as dune and interdune sediments on a broad desert plain. The source of the sand was the updip and adjacent alluvial fan, plain, and wadi deposits. A marine transgression was initiated late in Denkman deposition, resulting in the reworking of previously deposited Norphlet sediments. Norphlet hydrocarbon potential in southwestern and offshore Alabama is excellent with four oil and gas fields already established. Petroleum traps discovered to date are primarily structural traps involving salt anticlines, faulted salt anticlines, and extensional fault traps associated with salt movement. Reservoir rocks consist of quartzose sandstones, which are principally eolian in origin. Smackover algal carbonate mudstones were probably the source for the Norphlet hydrocarbons.

  13. Sea ice concentration and sea ice drift for the Arctic summer using C- and L-band SAR

    NASA Astrophysics Data System (ADS)

    Johansson, Malin; Berg, Anders; Eriksson, Leif

    2014-05-01

    The decreasing amount of sea ice and changes from multi-year ice to first year ice within the Arctic Ocean opens up for increased maritime activities. These activities include transportation, fishing and tourism. One of the major threats for the shipping is the presence of sea ice. Should an oil spill occur, the search and rescue is heavily dependent on constant updates of sea ice movements, both to enable a safer working environment and to potentially prevent the oil from reaching the sea ice. It is therefore necessary to have accurate and updated sea ice charts for the Arctic Ocean during the entire year. During the melt season that ice is subject to melting conditions making satellite observations of sea ice more difficult. This period coincides with the peak in marine shipping activities and therefore requires highly accurate sea ice concentration estimates. Synthetic Aperture Radar (SAR) are not hindered by clouds and do not require daylight. The continuous record and high temporal resolution makes C-band data preferable as input data for operational sea ice mapping. However, with C-band SAR it is sometimes difficult to distinguish between a wet sea ice surface and surrounding open water. L-band SAR has a larger penetration depth and has been shown to be less sensitive to less sensitive than C-band to the melt season. Inclusion of L-band data into sea chart estimates during the melt season in particular could therefore improve sea ice monitoring. We compare sea ice concentration melt season observations using Advanced Land Observing Satellite (ALOS) L-band images with Envisat ASAR C-band images. We evaluate if L-band images can be used to improve separation of wet surface ice from open water and compare with results for C-band.

  14. [Comparative proteomic analysis of cancerous and adjacent normal lung tissues].

    PubMed

    Lee, Ki Beom; Pi, Kyung Bae

    2010-01-01

    Lung cancer is the leading cause of cancer-related mortality in industrialized countries. Unfortunately, most lung cancers are found too late for a cure, therefore early detection and treatment is very important. We have applied proteomic analysis by using two-dimensional gel electrophoresis and peptide mass fingerprinting techniques for examination of cancerous and adjacent non-cancerous lung tissues from the same patient. The aim of the study was to find proteins, which could be used as biomarkers for diagnosis and monitoring of this disease. Indeed, we found differences in expression of several proteins, related to various cellular activities, such as, chaperoning (e.g., GRP96, GRP78, HSP27), metabolism and oxidation stress (e.g., L-fucose, GST), cytoskeleton (e.g., tubulin beta 2/3, beta actin), cell adhesion (e.g., annexin A5/3), binding proteins (e.g., 14-3-3 theta) and signal transduction. These changes may be important for progression of carcinogenesis; they may be used as the molecular-support for future diagnostic markers. PMID:21395069

  15. Hydrocarbon provinces and productive trends in Libya and adjacent areas

    SciTech Connect

    Missallati, A.A. Ltd., Tripoli )

    1988-08-01

    According to the age of major reservoirs, hydrocarbon occurrences in Libya and adjacent areas can be grouped into six major systems which, according to their geographic locations, can be classified into two major hydrocarbon provinces: (1) Sirte-Pelagian basins province, with major reservoirs ranging from middle-late Mesozoic to early Tertiary, and (2) Murzog-Ghadames basins province, with major reservoirs ranging from early Paleozoic to early Mesozoic. In the Sirte-Pelagian basins province, hydrocarbons have been trapped in structural highs or in stratigraphic wedge-out against structural highs and in carbonate buildups. Here, hydrocarbon generation is characterized by the combined effect of abundant structural relief and reservoir development in the same hydrocarbon systems of the same age, providing an excellent example of hydrocarbon traps in sedimentary basins that have undergone extensive tensional fracturing in a shallow marine environment. In the Murzog-Ghadames basins province, hydrocarbons have been trapped mainly in structural highs controlled by paleostructural trends as basement arches which acted as focal points for oil migration and accumulation.

  16. Snow Distribution Patterns in Clearings and Adjacent Forest

    NASA Astrophysics Data System (ADS)

    Golding, Douglas L.; Swanson, Robert H.

    1986-12-01

    Snow accumulation patterns were determined for clearings and adjacent forest at Marmot Creek experimental watershed and James River, Alberta. At maximum accumulation snow water equivalent (SWE) was greater in clearings than in forest whether clearings were large, as in 8- to 13-ha blocks where SWE averaged 20% more than in the forest, or small as in the ¼ to 6-H (height) diameter circular clearings where SWE was 13-45% greater than in the forest. SWE was 42 to 52% less in north than in south sectors of 2-6 H clearings. These differences increased with clearing size and time since beginning of accumulation period and are caused by snow ablation (melt and evaporation), a function of direct solar radiation reaching the snowpack. In such situations the snow that has accumulated on the ground cannot be considered a measure of the snow that has actually fallen there. For water balances and hydrologic modeling, snow measurements in partially cleared watersheds must be adjusted for temporal and spatial factors specific to the watershed.

  17. Particulate Matter Levels in Ambient Air Adjacent to Industrial Area

    NASA Astrophysics Data System (ADS)

    Mohamed, R. M. S. R.; Nizam, N. M. S.; Al-Gheethi, A. A.; Lajis, A.; Kassim, A. H. M.

    2016-07-01

    Air quality in the residential areas adjacent to the industrial regions is of great concern due to the association with human health risks. In this work, the concentrations of particulate matter (PM10) in the ambient air of UTHM campus was investigated tostudy the air qualityand their compliance to the Malaysian Ambient Air Quality Guidelines (AAQG). The PM10 samples were taken over 24 hours from the most significant area at UTHM including Stadium, KolejKediamanTunDr. Ismail (KKTDI) and MakmalBahan. The meteorological parameters; temperature, relative humidity, wind speed and wind direction as well as particulate matterwere estimated by using E-Sampler Particulate Matter (PM10) Collector. The highest concentrations of PM10 (55.56 µg/m3) was recorded at MakmalBahan during the working and weekend days. However, these concentrations are less than 150 pg/m3. It can be concluded that although UTHM is surrounded by the industrial area, the air quality in the campus still within the standards limits.

  18. The Thermomagnetic Instability in Superconducting Films with Adjacent Metal Layer

    NASA Astrophysics Data System (ADS)

    Vestgården, J. I.; Galperin, Y. M.; Johansen, T. H.

    2013-12-01

    Dendritic flux avalanches is a frequently encountered consequence of the thermomagnetic instability in type-II superconducting films. The avalanches, which are potentially harmful for superconductor-based devices, can be suppressed by an adjacent normal metal layer, even when the two layers are not in thermal contact. The suppression of the avalanches in this case is due to so-called magnetic braking, caused by eddy currents generated in the metal layer by propagating magnetic flux. We develop a theory of magnetic braking by analyzing coupled electrodynamics and heat flow in a superconductor-normal metal bilayer. The equations are solved by linearization and by numerical simulation of the avalanche dynamics. We find that in an uncoated superconductor, even a uniform thermomagnetic instability can develop into a dendritic flux avalanche. The mechanism is that a small non-uniformity caused by the electromagnetic non-locality induces a flux-flow hot spot at a random position. The hot spot quickly develops into a finger, which at high speeds penetrates into the superconductor, forming a branching structure. Magnetic braking slows the avalanches, and if the normal metal conductivity is sufficiently high, it can suppress the formation of the dendritic structure. During avalanches, the braking by the normal metal layer prevents the temperature from exceeding the transition temperature of the superconductor. Analytical criteria for the instability threshold are developed using the linear stability analysis. The criteria are found to match quantitatively the instability onsets obtained in simulations.

  19. Herbicide interchange between a stream and the adjacent alluvial aquifer

    USGS Publications Warehouse

    Wang, W.; Squillace, P.

    1994-01-01

    Herbicide interchange between a stream and the adjacent alluvial aquifer and quantification of herbicide bank storage during high streamflow were investigated at a research site on the Cedar River flood plain, 10 km southeast of Cedar Rapids, Iowa. During high streamflow in March 1990, alachlor, atrazine, and metolachlor were detected at concentrations above background in water from wells as distant as 20, 50, and 10 m from the river's edge, respectively. During high streamflow in May 1990, alachlor, atrazine, cyanazine, and metolachlor were detected at concentrations above background as distant as 20, 50, 10, and 20 m from the river's edge, respectively. Herbicide bank storage took place during high streamflow when hydraulic gradients were from the river to the alluvial aquifer and the laterally infiltrating river water contained herbicide concentrations larger than background concentrations in the aquifer. The herbicide bank storage can be quantified by multiplying herbicide concentration by the "effective area" that a well represented and an assumed porosity of 0.25. During March 1990, herbicide bank storage values were calculated to be 1.7,79, and 4.0 mg/m for alachlor, atrazine, and metolachlor, respectively. During May 1990, values were 7.1, 54, 11, and 19 mg/m for alachlor, atrazine, cyanazine, and metolachlor, respectively. ?? 1994 American Chemical Society.

  20. Apical infection spreading to adjacent teeth: a case report.

    PubMed

    Komabayashi, Takashi; Jiang, Jin; Zhu, Qiang

    2011-06-01

    This case report describes apical infection on tooth number 24 that spread to adjacent teeth, resulting in devitalized teeth numbers 23 and 25. The 25-year-old Caucasian female patient was referred to the endodontic resident clinic because of uncontrolled apical infection. Root-end surgery and root-end filling of teeth numbers 23, 24, and 25 were performed. The histopathological diagnosis was a periapical cyst; however, the clinical surgical finding of a purulence-filled bone cavity also revealed a periapical abscess. After root-end surgery and regenerative therapy using Mineral Trioxide Aggregate, Bio-Oss xenograft material, and Bio-Gide resorbable collagen membrane, the patient had no symptoms. Radiographs showed the apical lesion had healed satisfactorily at the 6-month, 1-year, and 2-year follow-ups. The clinical implication of this rare case suggests the importance of standard endodontic diagnostic procedures for pulpal and apical diagnosis, prevention of apical periodontitis exacerbation by reducing bacterial factors, and the effectiveness of healing large bone defects using regenerative materials. PMID:21458327

  1. Seismic responses of two adjacent buildings. I. Data and analyses

    USGS Publications Warehouse

    Celebi, Mehmet

    1993-01-01

    In this two-part paper, responses of two, adjacent, seven-story buildings in Norwalk, California, to the Whittier-Narrows, Calif, earthquake of Oct. 1, 1987 are studied. Building A, instrumented according to code recommendations, and building B, extensively instrumented, are offset by 16.3 m from one another. The data set includes motions from the superstructure of both buildings, from a downhole below the foundation of building B, and from three free-field sites. Part I of the paper includes descriptions of the buildings, site, instrumentation, and analysis of the data of each building. System identification and spectral analysis techniques are employed in part I. Building A has identical first-mode frequencies of 0.65 Hz for both building axes. The strong-motion response characteristics of building A are considerably different than those determined from low-amplitude tests. Building B has fundamental modes at 0.76 Hz and 0.83 Hz in the major and minor axes, respectively. Torsional and diaphragm effects in building B are negligible.

  2. Concentric network symmetry grasps authors' styles in word adjacency networks

    NASA Astrophysics Data System (ADS)

    Amancio, Diego R.; Silva, Filipi N.; Costa, Luciano da F.

    2015-06-01

    Several characteristics of written texts have been inferred from statistical analysis derived from networked models. Even though many network measurements have been adapted to study textual properties at several levels of complexity, some textual aspects have been disregarded. In this paper, we study the symmetry of word adjacency networks, a well-known representation of text as a graph. A statistical analysis of the symmetry distribution performed in several novels showed that most of the words do not display symmetric patterns of connectivity. More specifically, the merged symmetry displayed a distribution similar to the ubiquitous power-law distribution. Our experiments also revealed that the studied metrics do not correlate with other traditional network measurements, such as the degree or the betweenness centrality. The discriminability power of the symmetry measurements was verified in the authorship attribution task. Interestingly, we found that specific authors prefer particular types of symmetric motifs. As a consequence, the authorship of books could be accurately identified in 82.5% of the cases, in a dataset comprising books written by 8 authors. Because the proposed measurements for text analysis are complementary to the traditional approach, they can be used to improve the characterization of text networks, which might be useful for applications based on stylistic classification.

  3. Seismic responses of two adjacent buildings. II. Interaction

    USGS Publications Warehouse

    Celebi, Mehmet

    1993-01-01

    Presented in this part of the two-part paper is a study of the relations between earthquake motions recorded from two, adjacent, seven-story buildings, from a downhole below the foundation of one of the buildings and from three free-field sites, all within one city block. This unique data set was obtained during the Whittier-Narrows, Calif. earthquake of Oct. 1, 1987, Part I includes background information on the two buildings, the site, and the data set. Building response characteristics of a code-type instrumented building (A) and an extensively instrumented building (B) are also studied. In this part, spectral analysis techniques are used to study the relationships between the motions of the roofs and basements, the downhole and the free-field sites. It is asserted that there is building-soil-building interaction between the two buildings at a frequency of 2.35 Hz. Furthermore, the free-field motions are shown to be influenced by the presence of the buildings.

  4. Parasites of two native fishes in adjacent Adirondack lakes.

    PubMed

    Bauer, Eric F; Whipps, Christopher M

    2013-08-01

    This survey of parasites in 2 adjacent lakes is the first of its kind in the Adirondack Park of New York State. Wolf Lake is designated as a heritage lake whereas nearby Deer Lake is limnologically similar but has at least 5 introduced fish species. Both lakes have 2 native species, i.e., white sucker (Catostomus commersoni) and redbreast sunfish (Lepomis auritus), which were the focus of this study. Parasite communities of both hosts were surveyed and compared between each lake and were statistically evaluated for differences in species similarity, prevalence, mean intensity, and mean abundance. Between lakes, white suckers had significant differences in the prevalence of 4 parasite species (Myxobolus sp. 2, Myxobolus bibulatus, Octospinifer macilentis, and Pomphorhynchus bulbocoli) and mean abundances of 4 parasites (neascus larvae, Octospinifer macilentis, Pomphorhynchus bulbocoli, and Glaridacris confusus). Redbreast sunfish had significant differences in the prevalence of 3 species (Myxobolus uvuliferis, a coccidian species, and Spinitectus carolini) and differences in parasite mean abundance of 5 species (neascus larvae, Clinostomum marginatum , Leptorhynchoides thecatus, Spinitectus carolini, and Eustrongylides sp.). Differences in component communities between lakes were found and, although the exact causes cannot be determined by this study, we speculate on several possible explanations. PMID:23384764

  5. Natural Variability of Arctic Sea Ice Over the Holocene

    NASA Astrophysics Data System (ADS)

    Fisher, David; Dyke, Art; Koerner, Roy; Bourgeois, Jocelyne; Kinnard, Christophe; Zdanowicz, Christian; de Vernal, Anne; Hillaire-Marcel, Claude; Savelle, James; Rochon, André

    2006-07-01

    The area and volume of sea ice in the ArcticOcean is decreasing, with some predictingice-free summers by 2100 A.D. Johannessenet al., 2004. The implications ofthese trends for transportation and ecosystemsare profound; for example, summershipping through the Northwest Passagecould be possible, while loss of sea icecould cause stress for polar bears. Moreover,global climate may be affected throughalbedo feedbacks and increased sea ice productionand export. With more open water,more new sea ice forms in winter, whichmelts and/or gets exported out of the Arctic.

  6. Molecular biodiversity of Red Sea demosponges.

    PubMed

    Erpenbeck, Dirk; Voigt, Oliver; Al-Aidaroos, Ali M; Berumen, Michael L; Büttner, Gabriele; Catania, Daniela; Guirguis, Adel Naguib; Paulay, Gustav; Schätzle, Simone; Wörheide, Gert

    2016-04-30

    Sponges are important constituents of coral reef ecosystems, including those around the Arabian Peninsula. Despite their importance, our knowledge on demosponge diversity in this area is insufficient to recognize, for example, faunal changes caused by anthropogenic disturbances. We here report the first assessment of demosponge molecular biodiversity from Arabia, with focus on the Saudi Arabian Red Sea, based on mitochondrial and nuclear ribosomal molecular markers gathered in the framework of the Sponge Barcoding Project. We use a rapid molecular screening approach on Arabian demosponge collections and analyze results in comparison against published material in terms of biodiversity. We use a variable region of 28S rDNA, applied for the first time in the assessment of demosponge molecular diversity. Our data constitutes a solid foundation for a future more comprehensive understanding of sponge biodiversity of the Red Sea and adjacent waters. PMID:26776057

  7. Sea ice loss enhances wave action at the Arctic coast

    USGS Publications Warehouse

    Overeem, I.; Anderson, R. Scott; Wobus, C.W.; Clow, G.D.; Urban, F.E.; Matell, N.

    2011-01-01

    Erosion rates of permafrost coasts along the Beaufort Sea accelerated over the past 50 years synchronously with Arctic-wide declines in sea ice extent, suggesting a causal relationship between the two. A fetch-limited wave model driven by sea ice position and local wind data from northern Alaska indicates that the exposure of permafrost bluffs to seawater increased by a factor of 2.5 during 1979-2009. The duration of the open water season expanded from ???45 days to ???95 days. Open water expanded more rapidly toward the fall (???0.92 day yr-1), when sea surface temperatures are cooler, than into the mid-summer (???0.71 days yr-1).Time-lapse imagery demonstrates the relatively efficient erosive action of a single storm in August. Sea surface temperatures have already decreased significantly by fall, reducing the potential impact of thermal erosion due to fall season storm waves. Copyright 2011 by the American Geophysical Union.

  8. Solution notches, earthquakes, and sea level, Haiti

    NASA Astrophysics Data System (ADS)

    Schiffman, C. R.; Mildor, B. S.; Bilham, R. G.

    2010-12-01

    Shortly after the 12 January 2010 Haiti earthquake, we installed an array of five tide gauges to determine sea level and its variability in the region of uplifted corals on the coast SW of Leogane, Haiti, that had been uplift ≤30 cm during the earthquake. Each gauge consists of a pressure transducer bolted 50-80 cm below mean sea level, which samples the difference between atmospheric pressure and sea pressure every 10 minutes. The data are transmitted via the Iridium satellite and are publically available with a latency of 10 minutes to 2 hours. The measurements reveal a maximum tidal range of ≈50 cm with 2-4 week oscillations in mean sea level of several cm. Sea slope, revealed by differences between adjacent gauges, varies 2-5 cm per 10 km at periods of 2-5 weeks, which imposes a disappointing limit to the utility of the gauges in estimating post seismic vertical motions. A parallel study of the form and elevation of coastal notches and mushroom rocks (rocks notched on all sides, hence forming a mushroom shape), along the coast west of Petit Goave suggests that these notches may provide an uplift history of the region over the past several hundreds of years. Notch sections in two areas were contoured, digitized, and compared to mean sea level. The notches mimic the histogram of sea level, suggesting that they are formed by dissolution by acidic surface waters. Notches formed two distinct levels, one approximately 58 cm above mean sea level, and the other approximately 157 cm above mean sea level. Several landslide blocks fell into the sea during the 2010 earthquake, and we anticipate these are destined for conversion to future mushroom rocks. Surfaces have been prepared on these blocks to study the rate of notch formation in situ, and samples are being subjected to acid corrosion in laboratory conditions, with the hope that the depth of notches may provide an estimate of the time of fall of previous rocks to help constrain the earthquake history of this area

  9. Biodiversity and life strategies of deep-sea meiofauna and nematode assemblages in the Whittard Canyon (Celtic margin, NE Atlantic Ocean)

    NASA Astrophysics Data System (ADS)

    Gambi, Cristina; Danovaro, Roberto

    2016-02-01

    An extensive sampling strategy has been carried out along bathymetric transects in two branches (Eastern middle and Western) of the Whittard Canyon and in two adjacent open slopes to investigate meiofaunal assemblages (including nematode diversity and their life strategy) in the Celtic margin, Northern Gulf of Biscay. Our results show the presence of differences in terms of meiofaunal abundance and biomass among habitats even when located at the same depth. Meiofaunal abundance and biomass in the upper and middle (1000-2000 m) part of the branches of the Whittard Canyon are typically higher than those reported in adjacent open slopes while, in deeper sediments (ca. 3000 m), an opposite pattern is detected. The availability of food sources (both in term of quantity and quality) plays a key role in explaining such differences. Diversity expressed either as the richness of meiofaunal taxa and of nematode species is typically higher in slopes than in the branches of the Whittard Canyon. Turnover diversity is high (40-100% for meiofaunal rare taxa and 61-78% for nematode species, respectively) either among habitats and depths. Although a general dominance of deposit feeders, predators are more abundant in slopes (9-12% of total nematode abundance) than in both branches of the Whittard Canyon (4-7%). The higher fraction of predators of the nematode assemblages inhabiting the slopes determined higher values of the maturity index (i.e., more persisters, c-p=4/5). We hypothesize that the life strategies of nematode assemblages are influenced by gravity flows, sediment instability and the 2-3 times higher availability of phytopigments, which characterize the upper part of the Whittard Canyon, favoring opportunist/colonizer species. Our findings indicate that different deep-sea habitats are associated to different life strategies, thus contributing to increase the functional diversity of deep-sea ecosystems.

  10. On the Adjacency Matrix of RyR2 Cluster Structures.

    PubMed

    Walker, Mark A; Kohl, Tobias; Lehnart, Stephan E; Greenstein, Joseph L; Lederer, W J; Winslow, Raimond L

    2015-11-01

    In the heart, electrical stimulation of cardiac myocytes increases the open probability of sarcolemmal voltage-sensitive Ca2+ channels and flux of Ca2+ into the cells. This increases Ca2+ binding to ligand-gated channels known as ryanodine receptors (RyR2). Their openings cause cell-wide release of Ca2+, which in turn causes muscle contraction and the generation of the mechanical force required to pump blood. In resting myocytes, RyR2s can also open spontaneously giving rise to spatially-confined Ca2+ release events known as "sparks." RyR2s are organized in a lattice to form clusters in the junctional sarcoplasmic reticulum membrane. Our recent work has shown that the spatial arrangement of RyR2s within clusters strongly influences the frequency of Ca2+ sparks. We showed that the probability of a Ca2+ spark occurring when a single RyR2 in the cluster opens spontaneously can be predicted from the precise spatial arrangements of the RyR2s. Thus, "function" follows from "structure." This probability is related to the maximum eigenvalue (λ1) of the adjacency matrix of the RyR2 cluster lattice. In this work, we develop a theoretical framework for understanding this relationship. We present a stochastic contact network model of the Ca2+ spark initiation process. We show that λ1 determines a stability threshold for the formation of Ca2+ sparks in terms of the RyR2 gating transition rates. We recapitulate these results by applying the model to realistic RyR2 cluster structures informed by super-resolution stimulated emission depletion (STED) microscopy. Eigendecomposition of the linearized mean-field contact network model reveals functional subdomains within RyR2 clusters with distinct sensitivities to Ca2+. This work provides novel perspectives on the cardiac Ca2+ release process and a general method for inferring the functional properties of transmembrane receptor clusters from their structure. PMID:26545234

  11. On the Adjacency Matrix of RyR2 Cluster Structures

    PubMed Central

    Walker, Mark A.; Kohl, Tobias; Lehnart, Stephan E.; Greenstein, Joseph L.; Lederer, W. J.; Winslow, Raimond L.

    2015-01-01

    In the heart, electrical stimulation of cardiac myocytes increases the open probability of sarcolemmal voltage-sensitive Ca2+ channels and flux of Ca2+ into the cells. This increases Ca2+ binding to ligand-gated channels known as ryanodine receptors (RyR2). Their openings cause cell-wide release of Ca2+, which in turn causes muscle contraction and the generation of the mechanical force required to pump blood. In resting myocytes, RyR2s can also open spontaneously giving rise to spatially-confined Ca2+ release events known as “sparks.” RyR2s are organized in a lattice to form clusters in the junctional sarcoplasmic reticulum membrane. Our recent work has shown that the spatial arrangement of RyR2s within clusters strongly influences the frequency of Ca2+ sparks. We showed that the probability of a Ca2+ spark occurring when a single RyR2 in the cluster opens spontaneously can be predicted from the precise spatial arrangements of the RyR2s. Thus, “function” follows from “structure.” This probability is related to the maximum eigenvalue (λ1) of the adjacency matrix of the RyR2 cluster lattice. In this work, we develop a theoretical framework for understanding this relationship. We present a stochastic contact network model of the Ca2+ spark initiation process. We show that λ1 determines a stability threshold for the formation of Ca2+ sparks in terms of the RyR2 gating transition rates. We recapitulate these results by applying the model to realistic RyR2 cluster structures informed by super-resolution stimulated emission depletion (STED) microscopy. Eigendecomposition of the linearized mean-field contact network model reveals functional subdomains within RyR2 clusters with distinct sensitivities to Ca2+. This work provides novel perspectives on the cardiac Ca2+ release process and a general method for inferring the functional properties of transmembrane receptor clusters from their structure. PMID:26545234

  12. Advanced deep sea diving equipment

    NASA Technical Reports Server (NTRS)

    Danesi, W. A.

    1972-01-01

    Design requirements are generated for a deep sea heavy duty diving system to equip salvage divers with equipment and tools that permit work of the same quality and in times approaching that done on the surface. The system consists of a helmet, a recirculator for removing carbon dioxide, and the diver's dress. The diver controls the inlet flow by the recirculatory control valve and is able to change closed cycle operation to open cycle if malfunction occurs. Proper function of the scrubber in the recirculator minimizes temperature and humidity effects as it filters the returning air.

  13. Sea urchin granuloma.

    PubMed

    Rossetto, André Luiz; de Macedo Mora, Jamesson; Haddad Junior, Vidal

    2006-01-01

    Injuries caused by venomous and poisonous aquatic animals may provoke important morbidity in humans. The phylum Echinoderma include more than 6000 species of starfish, sea urchins, sand dollars, and sea cucumbers some of which have been found responsible for injuries to humans. Initial injuries by sea urchins are associated with trauma and envenomation, but later effects can be observed. Sea urchin granuloma is a chronic granulomatous skin disease caused by frequent and successive penetration of sea urchin spines which have not been removed from wounds. The authors report a typical case of sea urchin granuloma in a fisherman and its therapeutic implications. PMID:17086323

  14. Arctic and Antarctic Sea Ice Changes and Impacts (Invited)

    NASA Astrophysics Data System (ADS)

    Nghiem, S. V.

    2013-12-01

    The extent of springtime Arctic perennial sea ice, important to preconditioning summer melt and to polar sunrise photochemistry, continues its precipitous reduction in the last decade marked by a record low in 2012, as the Bromine, Ozone, and Mercury Experiment (BROMEX) was conducted around Barrow, Alaska, to investigate impacts of sea ice reduction on photochemical processes, transport, and distribution in the polar environment. In spring 2013, there was further loss of perennial sea ice, as it was not observed in the ocean region adjacent to the Alaskan north coast, where there was a stretch of perennial sea ice in 2012 in the Beaufort Sea and Chukchi Sea. In contrast to the rapid and extensive loss of sea ice in the Arctic, Antarctic sea ice has a trend of a slight increase in the past three decades. Given the significant variability in time and in space together with uncertainties in satellite observations, the increasing trend of Antarctic sea ice may arguably be considered as having a low confidence level; however, there was no overall reduction of Antarctic sea ice extent anywhere close to the decreasing rate of Arctic sea ice. There exist publications presenting various factors driving changes in Arctic and Antarctic sea ice. After a short review of these published factors, new observations and atmospheric, oceanic, hydrological, and geological mechanisms contributed to different behaviors of sea ice changes in the Arctic and Antarctic are presented. The contribution from of hydrologic factors may provide a linkage to and enhance thermal impacts from lower latitudes. While geological factors may affect the sensitivity of sea ice response to climate change, these factors can serve as the long-term memory in the system that should be exploited to improve future projections or predictions of sea ice changes. Furthermore, similarities and differences in chemical impacts of Arctic and Antarctic sea ice changes are discussed. Understanding sea ice changes and

  15. Helicopter Observations of the Sea Breeze over a Coastal Area.

    NASA Astrophysics Data System (ADS)

    Chiba, Osamu; Kobayashi, Fumiaki; Naito, Gen'ichi; Sassa, Koji

    1999-04-01

    Thermodynamical observations by a helicopter have been conducted to study the internal structure of the sea breeze blowing inland from Tosa Bay during three periods (September 1993, November 1994 and 1995). Inland-intrusion distances of the midday sea breeze observed at each flight leg were in the 10-25-km range, depending on the intensity of the ambient flow associated with the gradient wind, atmospheric stratification, and the geographical features of the observed area.The sea breeze observed over the sea had well-defined features, in particular a turbulent wake behind the head of the sea-breeze front and a closed sea-breeze circulation cell containing the subsidence of the return flow. In addition, a moist layer distributed around 15-20 km offshore forms because the land breeze moves in this region. Moreover, a calm condition exists from the coast to about 10 km offshore. Both phenomena are found before the onset of the sea breeze in the early morning. Such remarkable characteristics of the sea breeze are found over the sea, with a background of land-sea configuration that consists of a flat plain with small mountains and a bay opened out to sea.

  16. How Much Are Floridians Willing to Pay for Protecting Sea Turtles from Sea Level Rise?

    NASA Astrophysics Data System (ADS)

    Hamed, Ahmed; Madani, Kaveh; Von Holle, Betsy; Wright, James; Milon, J. Walter; Bossick, Matthew

    2016-01-01

    Sea level rise (SLR) is posing a great inundation risk to coastal areas. Some coastal nesting species, including sea turtle species, have experienced diminished habitat from SLR. Contingent valuation method (CVM) was used in an effort to assess the economic loss impacts of SLR on sea turtle nesting habitats for Florida coasts; and to elicit values of willingness to pay (WTP) of Central Florida residents to implement certain mitigation strategies, which would protect Florida's east coast sea turtle nesting areas. Using the open-ended and dichotomous choice CVM, we sampled residents of two Florida communities: Cocoa Beach and Oviedo. We estimated the WTP of households from these two cities to protect sea turtle habitat to be between 42 and 57 per year for 5 years. Additionally, we attempted to assess the impact of the both the respondents' demographics and their perception toward various situations on their WTP value. Findings include a negative correlation between the age of a respondent and the probability of an individual willing to pay the hypothetical WTP amount. We found that WTP of an individual was not dependent on prior knowledge of the effects of SLR on sea turtle habitat. The greatest indicators of whether or not an individual was willing to pay to protect sea turtle habitat were the respondents' perception regarding the trustworthiness and efficiency of the party which will implement the conservation measures and their confidence in the conservation methods used. Respondents who perceive sea turtles having an effect on their life were also more likely to pay.

  17. 50 CFR 648.59 - Sea Scallop Access Areas.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Scallop Access Area is open to scallop vessels, unless transiting pursuant to paragraph (f) of this... Access Area is open to scallop vessels, unless transiting pursuant to paragraph (f) of this section. (5... 50 Wildlife and Fisheries 10 2011-10-01 2011-10-01 false Sea Scallop Access Areas. 648.59...

  18. Glacial erosion and expected permafrost thickness of Fennoscandia and adjacent regions

    NASA Astrophysics Data System (ADS)

    Amantov, Aleksey

    2013-04-01

    temperatures and solve the Stefan's problem several known climate reconstructions were involved, but with account of possible ice-sheet related temperature depressions. In time-slices they were reinterpolated in agreement with changing the outlines of the ice sheets. Models of the basal sub-ice temperature based on relevant models for Greenland (Huybrechts P., 1996) and Antarctic ice sheets (Pattyn F., 2010) were accounted to estimate possible zonation and variability of warming effects of ice sheets. Expected lower permafrost thickness (first hundreds meters) and extent in the Barents region could be caused by unfavorable conditions and relatively high heat flow. Lowlands bearing major topographic ice streams were likely represented by taliks not affected by continuous permafrost or - depending on scenarios and parameters - were shortly affected by reduced permafrost with thick active layer. The same is expected for the Novaya Zemlya trench of the Kara Sea, while bordering shallow shelf parts were possibly characterized by thick permafrost, especially growing in time of eustatic ocean lowering. Permafrost in Fennoscandia and adjacent regions could be strongly variable but shortly relatively thick (hundreds meters) over large areas, including higher landscape on sedimentary cover west of Baltic - White Sea lowland. Linear taliks of discontinous permafrost zone on terrigenous sediments could contribute tunnel valley formation.

  19. Possible Factors affecting the Thermal Contrast between Middle-Latitude Asian Continent and Adjacent Ocean

    NASA Astrophysics Data System (ADS)

    Cheng, Huaqiong; Wu, Tongwen; Dong, Wenjie

    2015-04-01

    A middle-latitude Land-Sea thermal contrast Index was used in this study which has close connection to the East Asian summer precipitation. The index has two parts which are land thermal index defined as JJA 500-hPa geopotential height anomalies at a land area (75°-90° E, 40° -55°N ) and ocean thermal index defined as that at an oceanic area (140° -150°E, 35° -42.5°N). The impact of the surface heat flux and atmospheric diabatic heating over the land and the ocean on the index was studied. The results show that the surface heat flux over Eurasian inner land has little influence to the land thermal index, while the variation of the surface latent heat flux and long-wave radiation over the Pacific adjacent to Japan has highly correlation with the ocean thermal index. The changes with height of the atmospheric diabatic heating rates over the Eurasian inner land and the Pacific adjacent to Japan have different features. The variations of the middle troposphere atmospheric long-wave and short-wave radiation heating have significantly influences on land thermal index, and that of the low troposphere atmospheric long-wave radiation, short-wave radiation and deep convective heating also have impact on the yearly variation of the land thermal index. For the ocean thermal index, the variations of the surface layer atmospheric vertical diffuse heating, large-scale latent heating and long-wave radiation heating are more important, low and middle troposphere atmospheric large-scale latent heating and shallow convective heating also have impact on the yearly variation of the ocean thermal index. And then the ocean thermal index has closely connection with the low troposphere atmospheric temperature, while the land thermal index has closely connection with the middle troposphere atmospheric temperature. The Effect of the preceding global SST anomalies on the index also was analyzed. The relations of land thermal index and ocean thermal index and the global SST anomalies

  20. A Tale of Two Inlets: Tidal Currents at Two Adjacent Inlets in the Indian River Lagoon

    NASA Astrophysics Data System (ADS)

    Webb, B. M.; Weaver, R. J.

    2012-12-01

    The tidal currents and hydrography at two adjacent inlets of the Indian River Lagoon estuary (Florida) were recently measured using a personal watercraft-based coastal profiling system. Although the two inlets—Sebastian Inlet and Port Canaveral Inlet—are separated by only 60 km, their characteristics and dynamics are quite unique. While Sebastian Inlet is a shallow (~4 m), curved inlet with a free connection to the estuary, Port Canaveral Inlet is dominated by a deep (~13 m), straight ship channel and has limited connectivity to the Banana River through a sector gate lock. Underway measurements of tidal currents were obtained using a bottom tracking acoustic Doppler current profiler; vertical casts of hydrography were obtained with a conductivity-temperature-depth profiling instrument; and continuous underway measurements of surface water hydrography were made using a Portable SeaKeeper system. Survey transects were performed to elucidate the along-channel variability of tidal flows, which appears to be significant in the presence of channel curvature. Ebb and flood tidal currents in Sebastian Inlet routinely exceeded 2.5 m/s from the surface to the bed, and an appreciable phase lag exists between tidal stage and current magnitude. The tidal currents at Port Canaveral Inlet were much smaller (~0.2 m/s) and appeared to be sensitive to meteorological forcing during the study period. Although the lagoon has free connections to the ocean 145 km to the north and 45 km to the south, Sebastian Inlet likely drains much of the lagoon to its north, an area of ~550 sq. km.

  1. Diet and body mass of wintering ducks in adjacent brackish and freshwater habitats

    USGS Publications Warehouse

    Miller, M.R.; Burns, E.G.; Wickland, B.E.; Eadie, J.M.

    2009-01-01

    Field-collected and hunter-donated ducks obtained during September-January of 1997-98 and 1998-99 were used to determine if food habits and body mass of Northern Pintails (Anas acuta) and Mallards (A. platyrhynchos) wintering in Suisun Marsh (Suisun), California, a managed estuarine brackish marsh, differed from values in the adjacent Sacramento-San Joaquin River Delta (the Delta), a freshwater region of grain fields flooded after harvest. Ducks in Suisun fed primarily on seeds of Sea Purslane (Sesuvium verrucosum), followed by Alkali Bulrush (Schoenoplectus maritimus) and Wild Millet (Echinochloa crusgalli), together forming 73-90% (aggregate % dry mass) of the diets. Ducks in the Delta fed primarily on seeds of Smartweed (Polygonum spp.), followed by corn (Zea mays) and tomato seeds (Lycopersicon esculentum), together forming 62-88% of the diets. Pintails and Mallards collected in Suisun each had similar (5 of 11 seasonal comparisons) or greater (6 of the 11 comparisons) body mass compared to their conspecifics collected from the Delta (90% confidence interval analyses), despite a composite diet in the Delta having about 39% greater metabolizable energy content (ME) and 24% greater protein content than in Suisun. Therefore, diet quality alone was not a predictor of body mass in these two areas. Other factors must have been involved, such as greater food abundance and density, lower waterfowl abundance and density, or lower daily energy costs in Suisun. Direct measurement of these factors should explain the apparent inconsistencies in body mass relative to food quality in these brackish and freshwater habitats.

  2. Thermal evolution of the western South Atlantic and the adjacent continent during Termination 1

    NASA Astrophysics Data System (ADS)

    Chiessi, C. M.; Mulitza, S.; Mollenhauer, G.; Silva, J. B.; Groeneveld, J.; Prange, M.

    2015-06-01

    During Termination 1, millennial-scale weakening events of the Atlantic meridional overturning circulation (AMOC) supposedly produced major changes in sea surface temperatures (SSTs) of the western South Atlantic, and in mean air temperatures (MATs) over southeastern South America. It has been suggested, for instance, that the Brazil Current (BC) would strengthen (weaken) and the North Brazil Current (NBC) would weaken (strengthen) during slowdown (speed-up) events of the AMOC. This anti-phase pattern was claimed to be a necessary response to the decreased North Atlantic heat piracy during periods of weak AMOC. However, the thermal evolution of the western South Atlantic and the adjacent continent is so far largely unknown. Here we address this issue, presenting high-temporal-resolution SST and MAT records from the BC and southeastern South America, respectively. We identify a warming in the western South Atlantic during Heinrich Stadial 1 (HS1), which is followed first by a drop and then by increasing temperatures during the Bølling-Allerød, in phase with an existing SST record from the NBC. Additionally, a similar SST evolution is shown by a southernmost eastern South Atlantic record, suggesting a South Atlantic-wide pattern in SST evolution during most of Termination 1. Over southeastern South America, our MAT record shows a two-step increase during Termination 1, synchronous with atmospheric CO2 rise (i.e., during the second half of HS1 and during the Younger Dryas), and lagging abrupt SST changes by several thousand years. This delay corroborates the notion that the long duration of HS1 was fundamental in driving the Earth out of the last glacial.

  3. Thermal evolution of the western South Atlantic and the adjacent continent during Termination 1

    NASA Astrophysics Data System (ADS)

    Chiessi, C. M.; Mulitza, S.; Mollenhauer, G.; Silva, J. B.; Groeneveld, J.; Prange, M.

    2014-12-01

    During Termination 1, millennial-scale weakening events of the Atlantic meridional overturning circulation (AMOC) supposedly produced major changes in sea surface temperatures (SST) of the western South Atlantic, and in mean air temperatures (MAT) over southeastern South America. It was suggested, for instance, that the Brazil Current (BC) would strengthen (weaken) and the North Brazil Current (NBC) would weaken (strengthen) during slowdown (speed-up) events of the AMOC. This anti-phase pattern was claimed to be a necessary response to the decreased North Atlantic heat piracy during periods of weak AMOC. However, the thermal evolution of the western South Atlantic and the adjacent continent is largely unknown and a compelling record of the BC-NBC anti-phase behavior remains elusive. Here we address this issue, presenting high temporal resolution SST and MAT records from the BC and southeastern South America, respectively. We identify a warming in the western South Atlantic during Heinrich Stadial 1 (HS1), which is followed first by a drop and then by increasing temperatures during the Bølling-Allerød, in-phase with an existing NBC record. Additionally, a similar SST evolution is shown by a southernmost eastern South Atlantic record, suggesting a South Atlantic-wide pattern in SST evolution during most of Termination 1. Over southeastern South America, our MAT record shows a two-step increase during Termination 1, synchronous with atmospheric CO2 rise (i.e., during the second half of HS1 and during the Younger Dryas), and lagging abrupt SST changes by several thousand years. This delay corroborates the notion that the long duration of HS1 was fundamental to drive the Earth out of the last glacial.

  4. Polar bear population status in the northern Beaufort Sea, Canada, 1971-2006

    USGS Publications Warehouse

    Stirling, I.; McDonald, T.L.; Richardson, E.S.; Regehr, E.V.; Amstrup, Steven C.

    2011-01-01

    Polar bears (Ursus maritimus) of the northern Beaufort Sea (NB) population occur on the perimeter of the polar basin adjacent to the northwestern islands of the Canadian Arctic Archipelago. Sea ice converges on the islands through most of the year. We used open-population capture–recapture models to estimate population size and vital rates of polar bears between 1971 and 2006 to: (1) assess relationships between survival, sex and age, and time period; (2) evaluate the long-term importance of sea ice quality and availability in relation to climate warming; and (3) note future management and conservation concerns. The highest-ranking models suggested that survival of polar bears varied by age class and with changes in the sea ice habitat. Model-averaged estimates of survival (which include harvest mortality) for senescent adults ranged from 0.37 to 0.62, from 0.22 to 0.68 for cubs of the year (COY) and yearlings, and from 0.77 to 0.92 for 2–4 year-olds and adults. Horvtiz-Thompson (HT) estimates of population size were not significantly different among the decades of our study. The population size estimated for the 2000s was 980 ± 155 (mean and 95% CI). These estimates apply primarily to that segment of the NB population residing west and south of Banks Island. The NB polar bear population appears to have been stable or possibly increasing slightly during the period of our study. This suggests that ice conditions have remained suitable and similar for feeding in summer and fall during most years and that the traditional and legal Inuvialuit harvest has not exceeded sustainable levels. However, the amount of ice remaining in the study area at the end of summer, and the proportion that continues to lie over the biologically productive continental shelf (<300 m water depth) has declined over the 35-year period of this study. If the climate continues to warm as predicted, we predict that the polar bear population in the northern Beaufort Sea will eventually decline

  5. An Isotopic Investigation of Groundwater Recharge in the East Mesa Area of the Salton Sea Basin

    NASA Astrophysics Data System (ADS)

    Moran, J. E.; Tompson, A. F.; Demir, Z.

    2008-12-01

    The Salton Sea Basin, a closed topographic basin located in arid southeastern California and a portion of Baja California, Mexico, is home to some of the most productive agricultural lands in the United States. In the Imperial Valley, in the southern portion of the basin, groundwater use is limited owing to the wide availability of imported water, low urban demand, and water production and quality limitations. Intense interest in developing new water supplies and, separately, restoring the Salton Sea has led to renewed interest in the availability of groundwater in the Imperial Valley, especially the East Mesa area, where decades of leakage from unlined canals has likely impacted groundwater. This study uses isotopic tracers of the water molecule to examine the source of water and groundwater residence time in the East Mesa area between the All American and Coachella canals and the Salton Sea. Groundwater samples were collected from 12 wells and from the All American Canal at Drop 1 for stable isotopes of the water molecule and for tritium-helium groundwater age. Remote well locations, unfavorable well construction, and a dearth of monitoring wells with small open intervals, however, placed limitations on both sample integrity and on spatial coverage of the sampling area. The aridity of the Salton Sea area, and the long history of irrigation with Colorado River water, has marked the groundwater with an evaporated Colorado River water stable isotope signature. High tritium waters (captured in the extensive surface storage system of the Colorado River during peak fallout) that have infiltrated in the Salton Sea area make another good tracer of groundwater transport. Recently recharged groundwater, with tritium-helium apparent ages of less than 2 years, has a chemical and isotopic signature that closely matches water from the canal, and is found in wells directly adjacent to the All American canal. Mean apparent ages of 10 to 40 years were observed in wells at

  6. Tidally influenced alongshore circulation at an inlet-adjacent shoreline

    USGS Publications Warehouse

    Hansen, Jeff E.; Elias, Edwin P.L.; List, Jeffrey H.; Erikson, Li H.; Barnard, Patrick L.

    2013-01-01

    The contribution of tidal forcing to alongshore circulation inside the surfzone is investigated at a 7 km long sandy beach adjacent to a large tidal inlet. Ocean Beach in San Francisco, CA (USA) is onshore of a ∼150 km2 ebb-tidal delta and directly south of the Golden Gate, the sole entrance to San Francisco Bay. Using a coupled flow-wave numerical model, we find that the tides modulate, and in some cases can reverse the direction of, surfzone alongshore flows through two separate mechanisms. First, tidal flow through the inlet results in a barotropic tidal pressure gradient that, when integrated across the surfzone, represents an important contribution to the surfzone alongshore force balance. Even during energetic wave conditions, the tidal pressure gradient can account for more than 30% of the total alongshore pressure gradient (wave and tidal components) and up to 55% during small waves. The wave driven component of the alongshore pressure gradient results from alongshore wave height and corresponding setup gradients induced by refraction over the ebb-tidal delta. Second, wave refraction patterns over the inner shelf are tidally modulated as a result of both tidal water depth changes and strong tidal flows (∼1 m/s), with the effect from currents being larger. These tidally induced changes in wave refraction result in corresponding variability of the alongshore radiation stress and pressure gradients within the surfzone. Our results indicate that tidal contributions to the surfzone force balance can be significant and important in determining the direction and magnitude of alongshore flow.

  7. Tidally influenced alongshore circulation at an inlet-adjacent shoreline

    NASA Astrophysics Data System (ADS)

    Hansen, Jeff E.; Elias, Edwin; List, Jeffrey H.; Erikson, Li H.; Barnard, Patrick L.

    2013-03-01

    The contribution of tidal forcing to alongshore circulation inside the surfzone is investigated at a 7 km long sandy beach adjacent to a large tidal inlet. Ocean Beach in San Francisco, CA (USA) is onshore of a ˜150 km2 ebb-tidal delta and directly south of the Golden Gate, the sole entrance to San Francisco Bay. Using a coupled flow-wave numerical model, we find that the tides modulate, and in some cases can reverse the direction of, surfzone alongshore flows through two separate mechanisms. First, tidal flow through the inlet results in a barotropic tidal pressure gradient that, when integrated across the surfzone, represents an important contribution to the surfzone alongshore force balance. Even during energetic wave conditions, the tidal pressure gradient can account for more than 30% of the total alongshore pressure gradient (wave and tidal components) and up to 55% during small waves. The wave driven component of the alongshore pressure gradient results from alongshore wave height and corresponding setup gradients induced by refraction over the ebb-tidal delta. Second, wave refraction patterns over the inner shelf are tidally modulated as a result of both tidal water depth changes and strong tidal flows (˜1 m/s), with the effect from currents being larger. These tidally induced changes in wave refraction result in corresponding variability of the alongshore radiation stress and pressure gradients within the surfzone. Our results indicate that tidal contributions to the surfzone force balance can be significant and important in determining the direction and magnitude of alongshore flow.

  8. Seismotectonics of Northeastern United States and adjacent Canada

    SciTech Connect

    Yang, J.; Aggarwal, Y.P.

    1981-06-10

    Data for local earthquakes recorded by a network of stations in northeastern United States and adjacent Canada were analyzed to study the seismicity, the relationship between earthquakes and known faults, the state of stress, and crustal and upper mantle velocity structure. In addition, portable seismographs were deployed in the field to study aftershocks. As a result, accurate locations for about 364 local earthquakes (2< or =m/sub b/< or =5) and 22 focal mechanism solutions were determined. A comparison of the spatial distribution of these events (1970--1979) with historical earthquakes (1534--1959) reveals that seismic activity in the northeast is relatively stationary in space: those areas that have had little or no seismicity historically are relatively aseismic today, whereas the historically active areas are also active today. The instrumental locations, historical seismicity, and focal mechanism solutions show an internal consistency that help us distinguish two distinct seismogenic provinces. (1) The Adirondack-western Quebec province is a northwesterly trending zone of seismic activity, about 200 km wide and at least 500 km long, extending from the SE Adirondacks into western Quebec, Canada. Thrust faulting on planes striking NNW to NW appears to predominate, and the inferred axis of maximum horizontal compression is largely uniform and trends WSW, nearly parallel to the calculated absolute plate motion of North America. Little or no seismicity is found where anorthosite outcrops at the surface. Correlations between gravity anomalies and earthquake locations suggest that seismic activity in this zone is localized to regions of steep NE or SW gradient in Bouguer anomalies. This zone does not appear to extend southeastward to Boston, as proposed by some workers. (2) The Appalachian province is a northeasterly trending zone of seismic activity extending from northern Virginia to New Brunswick, Canada.

  9. Pond use by captive African penguins (Spheniscus demersus) in an immersive exhibit adjacent to human bathers.

    PubMed

    Ozella, Laura; Favaro, Livio; Carnovale, Irene; Pessani, Daniela

    2015-01-01

    Nonhuman animals in zoos are exposed to a continuous human presence, which affects their behaviors and welfare. However, little is known about what role the "visitor effect" has on penguins in captivity. The African penguin (Spheniscus demersus) is an endangered species commonly housed in zoos worldwide. The aim of this study was to evaluate whether the abundance of human bathers could reduce the average time spent in the water of a colony of African penguins housed in an exhibit where their pond habitat was adjacent to a swimming pool. Observations were carried out on 7 penguins in the summer of 2009. Data were collected during 3 time periods (Time 1 [T1] = opening of the swimming season, Time 2 [T2] = core of the season, Time 3 [T3] = late season) of 14 days each. The human disturbance caused by bathers strongly reduced the pond use by penguins at T1 and T2, especially when there were large numbers of visitors. However, at T3, we observed that the overall use of the pond by penguins increased, and the average duration of their diving was no longer dependent on the number of visitors. PMID:25402201

  10. Aral Sea basin: a sea dies, a sea also rises.

    PubMed

    Glantz, Michael H

    2007-06-01

    The thesis of this article is quite different from many other theses of papers, books, and articles on the Aral Sea. It is meant to purposely highlight the reality of the situation in Central Asia: the Aral Sea that was once a thriving body of water is no more. That sea is dead. What does exist in its place are the Aral seas: there are in essence three bodies of water, one of which is being purposefully restored and its level is rising (the Little Aral), and two others which are still marginally connected, although they continue to decline in level (the Big Aral West and the Big Aral East). In 1960 the level of the sea was about 53 m above sea level. By 2006 the level had dropped by 23 m to 30 m above sea level. This was not a scenario generated by a computer model. It was a process of environmental degradation played out in real life in a matter of a few decades, primarily as a result of human activities. Despite wishes and words to the contrary, it will take a heroic global effort to save what remains of the Big Aral. It would also take a significant degree of sacrifice by people and governments in the region to restore the Big Aral to an acceptable level, given that the annual rate of flow reaching the Amudarya River delta is less than a 10th of what it was several decades ago. Conferring World Heritage status to the Aral Sea(s) could spark restoration efforts for the Big Aral. PMID:17626470

  11. Triticella minini - a new ctenostome bryozoan from the abyssal plain adjacent to the Kuril-Kamchatka Trench

    NASA Astrophysics Data System (ADS)

    Grischenko, Andrei V.; Chernyshev, Alexei V.

    2015-01-01

    A new species of ctenostome bryozoan, Triticella minini sp. nov., is described from the abyssal plain adjacent to the Kuril-Kamchatka Trench, based on material collected by the Russian-German deep-sea expedition KuramBio 2012. Colonies of T. minini sp. nov. were found attached to the oral spines of irregular sea urchin Echinosigra (Echinogutta) amphoraMironov, 1974 by means of rhizoid fibers that penetrated the substratum through circular borings. The specimens were examined by light microscopy, scanning electron microscopy, and confocal laser scanning microscopy with phalloidin and nuclear labeling. The description of T. minini sp. nov. combines a general taxonomic description with a description of the anatomy of the muscular system. The new species differs from congeners in lacking a stolon. It has an intertentacular organ. T. minini sp. nov. is the eleventh species described in the genus TriticellaDalyell, 1848, and the first record for this genus from the northwestern Pacific. The new species is the fifth ctenostome bryozoan known to occur in 5001-5500 m depth interval worldwide, and the deepest record reported for Triticella.

  12. [Hygiene problems in inland and sea navigation].

    PubMed

    Goethe, H

    1983-09-01

    Both waste and sewage disposal are ubiquitous problems which have also affected navigation. Shipping is a very important transport carrier on a worldwide basis which together with the fishing industry employs roughly two million people. The problems associated with waste and sewage disposal obviously present a severe hazard to the coastal areas, narrow sea basins and, in particular, to inland and open-sea waterways. These problems are particularly alarming in large sea-ports, docks without outfall etc. The reduction of the crews aboard the ships operated by the industialised countries has helped to quantitatively ease the problem of waste and sewage disposal caused by the crews. However, passenger steamers with high waste and sewage volumes cause considerable nuisance in small harbours and the same holds for the disposal of technical waste products from ships such as dunnage packing material, ropes, plastic material, oil, etc. The quantity of waste water aboard a sea-going vessel including that from the toilets, washrooms, galley, and cleaning is rather considerable and is estimated at 300 litres per person and day under tropical climates. The volume of waste varies greatly and depends mainly on the type of material used aboard as mentioned above. Passenger liners with a very high volume of kitchen refuse and other solid waste give rise to specially insidious problems. In the past, sea-going vessels as well as ships employed in inland navigation used to throw overboard any type of refuse and sewage. However, during the last few decades the port authorities and also governments have introduced local and national regulations ruling that waste may no longer be thrown into harbour basins, but must be collected and disposed of on shore. Most ships have complied with these provisions, but some of them kept the collected refuse aboard and disposed of it on the open sea outside the harbours. International agreements on the prohibition of emptying oil and oil

  13. Non-migratory breeding by isolated green sea turtles (Chelonia mydas) in the Indian Ocean: biological and conservation implications.

    PubMed

    Whiting, Scott D; Murray, Wendy; Macrae, Ismail; Thorn, Robert; Chongkin, Mohammad; Koch, Andrea U

    2008-04-01

    Green sea turtles (Chelonia mydas) are renowned for their long-distance migrations but have less fame for short-distance migrations or non-migratory behavior. We present satellite telemetric evidence from Cocos (Keeling) Islands, Indian Ocean for the first predominantly non-migratory green sea turtle (C. mydas) population. The mean migration distance from the nesting beach to the foraging grounds was 35.5 km with a maximum mean transit time of 3.4 days. The behavior of this population has major implications for our general understanding of green turtle behavior and their life cycle and for conservation. Firstly, these results indicate a level of juvenile or adult non-breeding homing behavior from the open ocean to foraging grounds adjacent to their natal nesting beach. Secondly, a non-migratory breeding phase reduces the consumption of reproductive energy utilized, potentially resulting in higher fecundity for this population. Thirdly, the close proximity of the nesting and foraging habitats allows for uniformity in management and conservation strategies rarely possible for wide-ranging green turtle populations. PMID:18046497

  14. Non-migratory breeding by isolated green sea turtles ( Chelonia mydas) in the Indian Ocean: biological and conservation implications

    NASA Astrophysics Data System (ADS)

    Whiting, Scott D.; Murray, Wendy; Macrae, Ismail; Thorn, Robert; Chongkin, Mohammad; Koch, Andrea U.

    2008-04-01

    Green sea turtles ( Chelonia mydas) are renowned for their long-distance migrations but have less fame for short-distance migrations or non-migratory behavior. We present satellite telemetric evidence from Cocos (Keeling) Islands, Indian Ocean for the first predominantly non-migratory green sea turtle ( C. mydas) population. The mean migration distance from the nesting beach to the foraging grounds was 35.5 km with a maximum mean transit time of 3.4 days. The behavior of this population has major implications for our general understanding of green turtle behavior and their life cycle and for conservation. Firstly, these results indicate a level of juvenile or adult non-breeding homing behavior from the open ocean to foraging grounds adjacent to their natal nesting beach. Secondly, a non-migratory breeding phase reduces the consumption of reproductive energy utilized, potentially resulting in higher fecundity for this population. Thirdly, the close proximity of the nesting and foraging habitats allows for uniformity in management and conservation strategies rarely possible for wide-ranging green turtle populations.

  15. Episodic sea-floor spreading in the Southern Red Sea

    NASA Astrophysics Data System (ADS)

    Almalki, Khalid A.; Betts, Peter G.; Ailleres, Laurent

    2014-03-01

    The Red Sea represents the most spectacular example of a juvenile ocean basin on the modern Earth. Synthesis of regional aeromagnetic data, gravity data, seismic refraction data coupled with structural mapping from the Farasan Islands suggest that the opening of the Red Sea is complex and episodic. Modeling of magnetic and gravity data constrained by seismic refraction data reveals the Arabian Shelf is underlain by oceanic and transitional crust and that mafic diking and intrusions are focused at the continental-transitional crust boundary. This relationship is interpreted to indicate that early Miocene diking along the Arabian Escarpment heralded termination of oceanic basin formation and a shift in the locus of extension focused from a central mid-ocean ridge spreading center to the continental-transitional crust zone. Uplift along the Arabian Escarpment caused erosion and Middle to Late Miocene sedimentation of the Farasan Bank onto existing oceanic crust, suggesting that the extensive sedimentary banks of the southern Red Sea are not passive margins. Re-initiation of spreading occurred at ca 5 Ma. Pliocene to Pleistocene Shelf reef systems (Farasan Islands), developed on the flanks of the spreading ridge, are extensively overprinted by normal faults, suggesting that not all crustal extension is accommodated by active spreading.

  16. Host plant shifts and transitions into new adaptive zones in leafhoppers:
    the example of Macropsinae (Homoptera: Auchenorrhyncha: Cicadellidae)
    of Russia and adjacent countries.

    PubMed

    Tishechkin, Dmitri Yu

    2016-01-01

    The modes of diversification of Palaearctic Macropsinae (Homoptera: Auchenorrhyncha: Cicadellidae) are reconstructed based on data on their host plants and distribution in Russia and the adjacent territories. Macropsinae (Homoptera: Auchenorrhyncha: Cicadellidae) is originally an Oriental group, which penetrated into the Palaearctic from Southeast Asia. The genus Pediopsoides and species of the genus Macropsis that feed on East Asian oaks have not dispersed beyond broadleaf forests of the Eastern Palaearctic. Apparently, Pediopsis and elm-feeding species of Macropsis initially dispersed throughout the entire broadleaf forest zone. Division of this zone into two widely separated parts in temperate areas of Europe and East Asia (nemoral disjunction), produced closely related vicariant pairs of sister species. The genus Oncopsis and species of Macropsis feeding on Salicaceae dispersed throughout the entire Palaearctic following their host plants. Both lineages penetrated into riparian forests of the foothills and midlands of Central Asia, where they produced endemic species. The Central Asian Macropsis lineage shifted from Salicaceae to trees and shrubs of unrelated families (wild roses, barberry, oleaster, and sea-buckthorn) growing in the same biotopes. Subsequent diversification on those plants produced several separate host-associated species-groups, some of which penetrated following their hosts from riparian forests into arid habitats. One such lineage apparently shifted from shrubs to wormwood species (Artemisia spp.) and thus gave rise to the genus Macropsidius. This genus underwent adaptive radiation on wormwood species in the plains of South Kazakhstan and Central Asia; advancing westward, it formed secondary centres of diversity in Transcaucasia and the Mediterranean. Finally, some lineage of Macropsidius (or its sister-group) switched from feeding on Artemisia to polyphagy, yielding the ancestral form of the genus Hephathus. In general, the evolution of

  17. Comparisons of various sea level reconstructions and sea level from data synthesis products: 1960-2012

    NASA Astrophysics Data System (ADS)

    Carson, Mark; Stammer, Detlef; Köhl, Armin; Meyssignac, Benoit; Church, John; Schröter, Jens; Wenzel, Manfred

    2016-04-01

    We investigate sea level trends and variability as reconstructed from tide gauge data and ocean data assimilations (ODA) over the last 60 years. Tide gauge reconstructions (TGR) are mostly based on statistical approaches using selected EOFs, or trained from variability patterns, from altimetric sea level and tide gauge data to extrapolate regional sea level evolution backward in time. Reconstructions also exist from dynamical ocean modeling approaches with and without data assimilation. We intercompare all results and provide ensemble mean and ensemble spreads to describe estimates of past regional sea level changes and their uncertainties. While tide gauge reconstructions match tide gauge data better than ODA, they exhibit less variability in the open ocean. TGRs match the trends and variability better during the satellite-altimetry era than for the entire period from 1960-2012, whereas the ODAs mostly do not. An average of all products produces the best statistics for comparing to the set of tide gauges. The results are mixed. The TGRs and ODAs can be useful in some respects, such as calculating a global sea-level signal, and matching altimetric data, and each other, well in the Pacific. But the regional open-ocean sea-level change and variability found from altimetric data are not well reproduced over substantial portions of the ocean. Over periods earlier than the satellite era, these reconstructed regional patterns may not be trustworthy, nor can they be verified.

  18. Sea ice transports in the Weddell Sea

    NASA Astrophysics Data System (ADS)

    Harms, Sabine; Fahrbach, Eberhard; Strass, Volker H.

    2001-05-01

    Time series of sea ice draft in the Weddell Sea are evaluated together with hydrographic observations, satellite passive microwave data, and ice drift for estimation of the freshwater fluxes into and out of the Weddell Sea. Ice draft is measured with moored upward looking sonars since 1990 along two transects across the Weddell Gyre. One transect, extending from the tip of the Antarctic Peninsula to Kapp Norvegia, was sampled between 1990 and 1994 and covers the flow into and out of the southern Weddell Sea. The other transect, sampled since 1996 and extending from the Antarctic continent northward along the Greenwich meridian, covers the exchange of water masses between the eastern and the western Weddell Sea. In order to relate results obtained during the different time periods, empirical relationships are established between the length of the sea ice season, derived from the satellite passive microwave data and defined as the number of days per year with the sea ice concentration exceeding 15%, and (1) the annual mean ice draft and (2) the annual mean ice volume transport. By using these empirical relationships, estimates of annual mean ice drafts and ice volume transports are derived at all mooring sites for the period February 1979 through February 1999. Wind and current force a westward ice transport in the coastal areas of the eastern Weddell Sea and a northward ice transport in the west. During the 2-year period 1991/1992 the mean ice volume export from the Weddell Sea is (50 ± 19) × 103 m3 s-1. This freshwater export is representative for a longer-term (20-year) mean and exceeds the average amount of freshwater gained by precipitation and ice shelf melt by about 19×103 m3 s-1, yielding an upper bound for the formation rate of newly ventilated bottom water in the Weddell Sea of 2.6 Sv.

  19. Relationships between deep-sea tunicate populations west and east of the Straits of Gibraltar

    NASA Astrophysics Data System (ADS)

    Monniot, Claude; Monniot, Françoise

    Twenty-four species of tunicates were collected from deep bottoms on each side of the Gibraltar sill, in the adjacent Mediterranean Sea and Atlantic Ocean. In the Atlantic, stations bathed by Atlantic and Mediterranean waters were both sampled. No transport of ascidian taxa by the outflow of Mediterranean water into the Atlantic is apparent. The alternative hypothesis of an Atlantic origin of bathyal ascidian species in the Mediterranean Sea is proposed.

  20. Device for desalting sea or brackish water by using solar energy

    SciTech Connect

    Clavier, P.

    1981-09-29

    A device is described for desalting sea or brackish water using solar energy. It includes two adjacent canals or equivalent structures fed with the sea or brackish water, a green house type structure over one of the canals to vaporize water from it and a structure for condensation of water and for collecting softwater, the structure being in communication with the greenhouse structure and largely immersed in the other canal, which acts as the cold source for the condensating unit.