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Sample records for sea northeastern indian

  1. Examining the Bicultural Ethnic Identity of Adolescents of a Northeastern Indian Tribe

    ERIC Educational Resources Information Center

    Brown, Carrie M.; Smirles, Kimberly Eretzian

    2005-01-01

    The history of northeastern tribes differs substantially from that of other tribes, as northeastern tribes have experienced a longer length of contact with settlers and more intermarriage with non-Indians, producing tribal members of various ethnic backgrounds. American Indians can be considered "bicultural" because they must adapt to two…

  2. Hydrogeology of the Fort Peck Indian Reservation, northeastern Montana

    SciTech Connect

    Thamke, J.N.; Craigg, S.D. )

    1993-04-01

    The Fort Peck Indian Reservation, which encompasses about 3,300 square miles in northeastern Montana, is characterized by three major types of terrain: Missouri River bottom lands, badlands, and topographically higher benchlands. The reservation lies on the western flank of the Williston Basin, a large, petroleum-rich structural depression in Montana, North and South Dakota, and Saskatchewan and Manitoba, Canada. Structurally, the area is not complex, although the Poplar Anticline trends northwest through the central part of the reservation. The East Poplar Oil Field lies astride this structure and produces from the mississippian Madison Group. Geologic units that crop out in the reservation are the Upper Cretaceous Bearpaw Shale, Fox Hills Sandstone, and Hell Creek Formation; the Tertiary Fort Union and Flaxville Formations; and Quaternary glacial and alluvial deposits. Most ground water is produced from alluvial deposits, glacial deposits, Flaxville Formation, Fort Union Formation, Hell Creek Formation, and Fox Hills Sandstone. Well depths range from about 15 to 300 feet below land surface; depth to water ranges from about 5 to 160 feet. Units deeper than the Fox Hills Sandstone are not important aquifers because of the underlying, thick Bearpaw Shale, and because the water is too mineralized for most uses. Background dissolved-solids concentrations of water from major aquifers is in the range of about 300 to 3,000 milligrams per liter. However, in the East Poplar Oil Field, water in the alluvial and glacial deposits has been contaminated near brine-disposal facilities; dissolved-solids concentration of water is as much as 114,000 milligrams per liter.

  3. The Federal Cylinder Project: A Guide to Field Cylinder Collections in Federal Agencies. Volume 2, Northeastern Indian Catalog and Southeastern Indian Catalog.

    ERIC Educational Resources Information Center

    Gray, Judith A., Ed.; And Others

    Two catalogs inventory field-recorded wax cylinders which document the music and language of Indian tribes in northeastern and southeastern United States from 1890-1930. The Northeastern Indian Catalog contains entries for 738 cylinders comprising 16 music and spoken word collections from the Chippewa, Fox, Iroquois, Kickapoo, Menominee,…

  4. Epibenthic community variability in the northeastern Chukchi Sea

    NASA Astrophysics Data System (ADS)

    Ravelo, Alexandra M.; Konar, Brenda; Trefry, John H.; Grebmeier, Jacqueline M.

    2014-04-01

    Epibenthic organisms can occur in large numbers and high biomass on the continental shelf of the northeastern Chukchi Sea. From an ecosystem perspective, epibenthic organisms are important in recycling and redistributing organic matter deposited from the pelagic zone, and they also are key members of the local food web. Data for biological (epibenthic species composition, abundance, and biomass) and environmental (bottom water temperature, salinity, dissolved oxygen and pH, sediment grain size, sediment organic matter and sediment chlorophyll content, latitude, longitude, and water depth) variables were collected at 53 stations in the northeastern Chukchi Sea during the summers of 2009-2010 to characterize the epibenthos and provide a benchmark for potential future changes due to possible anthropogenic disturbances. Community biomass, abundance, species composition and taxa richness varied in patches throughout the study area, but were generally dominated by crustaceans and echinoderms. These two groups had an inverse relationship in the distribution of their dominance. Communities dominated by crustaceans had significantly higher Simpson's dominance and Pielou's evenness values compared to echinoderm-dominated communities. Correlation coefficients for six environmental variables (longitude, bottom water temperature, water depth, bottom water dissolved oxygen, sediment grain size 2 phi and total organic carbon) with epifaunal abundance and biomass were moderate (0.42 for abundance and 0.51 for biomass at a significance level of 0.1%). However, assemblages within the study area followed a distinct spatial distribution pattern that matched the path of important water masses in the region.

  5. Northeastern Ionian Sea: Palaeoceanographic variability over the last 22 ka

    NASA Astrophysics Data System (ADS)

    Geraga, M.; Mylona, G.; Tsaila-Monopoli, St.; Papatheodorou, G.; Ferentinos, G.

    2008-11-01

    The sediments of a deep sea core (Z1) taken from the north-eastern part of the Ionian Sea near Corfu Island (Greece) was studied in order to reconstruct the palaeoenvironmental history of the basin over the time interval between 22 and 1.5 ka. The downcore variation in the associations of planktonic foraminifera provides a continuous record of the faunal changes over this period. A succession of eight (8) main biozones, based on the major changes in the planktonic foraminifera record, were recognized. Their comparisons with records from the Tyrrhenian and the Adriatic Seas have shown that there is a similarity and synchroneity in the zonation. Furthermore, the downcore compositional changes of the planktonic foraminiferal assemblages and the δ18Ο signal made possible allowed the recognition of millennial to centennial climatic instabilities. These climatic instabilities are associated with the Heinrich 1 (H1) event, the GI-1a to GI-1e INTIMATE events, the Younger Dryas and the Holocene cool events at 8.2 ka, 7 ka, 5 ka, 4 ka and 3 ka. R-mode factor analysis applied to the percentage abundance of plantkonic foraminifera species from seven cores in the Ionian, Adriatic and Tyrrhenian Seas showed that the faunal composition in the three seas was controlled by temporal and spatial variations in: (i) the sea surface temperature, (ii) the stratification and mixing of the surficial waters and (iii) the fertility of surface waters associated with upwelling and/or river inputs. These variations were in phase or out of phase in the three seas.

  6. Peculiarities of the deep structure of the lithosphere in the northeastern part of the Indian Ocean

    NASA Astrophysics Data System (ADS)

    Mazo, E. L.; Shreider, A. A.; Kulikova, M. P.; Gilod, D. A.; Shreider, Al. A.

    2009-12-01

    The seismicity of the northeastern part of the Indian Ocean in connection with the general structural peculiarities of the main tectonic structures of the bottom is presented. The three main ranges of higher seismic activity at the depths of 0-17, 20-27, and 32-35 km divided by aseismic layers are revealed. The seismic activity at depths of more than 35 km is almost not detected both for the ocean and for the Indian peninsula. The nature of the distribution of the seismicity as such in the lithosphere is discussed. Using the results of anomalous au]gravitational field transformations, the prolongation of the East Indian Ridge structure is revealed to 19 degrees north, while the relationship of the Afanasy Nikitin Rise and the 85th Degree Ridge is not reflected at the tranforms. In the Cocos Basin, the mutually perpendicular disturbance zones of northeastern and northwestern strike, as well as the point of their crossing, where the maximal number of earthquake foci are concentrated, are distinguished. A conclusion concerning the substantial disturbance of the strength properties of the lithosphere in this zone as a consequence of the geodynamical processes, which are accompanied by fracture tectonics, is reached.

  7. 77 FR 65136 - Fisheries of the Northeastern United States; Black Sea Bass Fishery; Recreational Quota Harvested

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-25

    ... the 2012 fishing year is 1.86 million lb (844 mt) (76 FR 82189, December 30, 2011). The 2012 RHL was... Northeastern United States; Black Sea Bass Fishery; Recreational Quota Harvested AGENCY: National Marine...: Temporary rule; closure. SUMMARY: NMFS announces that the 2012 black sea bass recreational harvest limit...

  8. Variations in productivity and eolian fluxes in the northeastern Arabian Sea during the past 110 ka

    NASA Astrophysics Data System (ADS)

    Pourmand, Ali; Marcantonio, Franco; Schulz, Hartmut

    2004-04-01

    High-resolution (one to two samples/ka) radionuclide proxy records from core 93KL in the northeastern Arabian Sea provide evidence for millennial climate variability over the past 110 ka. We interpret 230Th-normalized 232Th fluxes as a proxy for eolian input, and authigenic uranium concentrations as a proxy for past productivity. We attribute orbital and suborbital variations in both proxies to changes in the intensity of the southwest Indian Ocean monsoon. The highest 230Th-normalized 232Th fluxes occur at times that are consistent with the timing of the Younger Dryas, Heinrich events 1-7 and cold Dansgaard-Oeschger stadial events recorded in the GISP2 ice core. Such high dust fluxes may be due to a weakened southwest monsoon in conjunction with strengthened northwesterlies from the Arabian Peninsula and Mesopotamia. Authigenic uranium concentrations, on the other hand, are highest during warm Dansgaard-Oeschger interstadials when the southwest monsoon is intensified relative to the northwesterly winds. Our results also indicate that on orbital timescales maximum average eolian fluxes coincide with the timing of marine isotopic stage (MIS) 2 and 4, while minimum fluxes occur during MIS 1, 3 and 5. Although the forcing mechanism(s) controlling suborbital variabilities in monsoonal intensity is still debated, our findings suggest an atmospheric teleconnection between the low-latitude southwest monsoon and North Atlantic climate.

  9. Assessment of gray whale feeding grounds and sea floor interaction in the northeastern Bering Sea

    USGS Publications Warehouse

    Nelson, C.H.; Johnson, K.R.; Barber, John H.

    1983-01-01

    A dense ampeliscid amphipod community in Chirikov Basin and around St. Lawrence Island in the northeastern Bering Sea has been outlined by summarizing biological studies, analyzing bioturbation in sediment samples, and examining sea floor photos and videotapes. The amphipod population is associated with a homogeneous, relict fine-grained sand body 0.10-1.5 m thick that is deposited during the marine transgression over the Bering land bridge 8,000-10,000 yr B.P. Modern current and water mass movements and perhaps whale feeding activity prevent modern deposition in this area. The distribution of the transgressive sand sheet, associated amphipod community and feeding gray whales mapped by aerial survey correlate closely with three types of sea-floor pits observed on high (500 kHz) and low (105 kHz) resolution side-scan sonar; they are attributed to gray whale feeding traces and their subsequent current scour modification. The fresh and modified feeding pits are present in 22,000 km2 of the basin and they cover a total of 2 to 18% of the sea floor in different areas of the feeding region. The smallest size class of pits approximates whale mouth gape size and is assumed to represent fresh whale feeding pits. Fresh feeding disturbance of the sea floor is estimated to average about 5.7% for a full feeding season. Combined with information that 34% of the measured benthic biomass is amphipod prey species, and calculating the number of gray whale feeding days in the Alaskan waters plus amount consumed per day, it can be estimated that Chirikov Basin, 2% of the feeding area, supplies a minimum of 5.3 to 7.1% of the gray whale's food resource in the Bering Sea and Arctic Ocean. If a maximum of 50% of the fresh feeding features are assumed to be missed because they parallel side-scan beam paths, then a maximum whale food resource of 14.2% is possible in northeastern Bering Sea. Because of side-scan techniques and possible higher amphipod biomass estimates, a reasonable minimum

  10. Ethnobotany in Intermedical Spaces: The Case of the Fulni-ô Indians (Northeastern Brazil)

    PubMed Central

    Soldati, Gustavo Taboada; Paulino de Albuquerque, Ulysses

    2012-01-01

    We analyzed the Fulni-ô medical system and introduced its intermedical character based on secondary data published in the literature. Then we focused on the medicinal plants known to the ethnic group, describing the most important species, their therapeutic uses and the body systems attributed to them. We based this analysis on the field experience of the authors in the project Studies for the Environmental and Cultural Sustainability of the Fulni-ô Medical System: Office of Medicinal Plant Care. This traditional botanical knowledge was used to corroborate the hybrid nature of local practices for access to health. We show that intermedicality is a result not only of the meeting of the Fulni-ô medical system with Biomedicine but also of its meeting with other traditional systems. Finally, we discuss how traditional botanical knowledge may be directly related to the ethnogenesis process led by the Fulni-ô Indians in northeastern Brazil. PMID:21961025

  11. Bajocian-Bathonian (Middle Jurassic) sea-level changes in northeastern Egypt: Synthesis and further implications

    NASA Astrophysics Data System (ADS)

    Ruban, Dmitry A.; Sallam, Emad S.

    2016-08-01

    The global eustatic developments can benefit significantly from properly acquired regional information. Summarizing the available interpretations of the relative sea-level changes from two areas in northeastern Egypt, namely Gebel Maghara and Khashm El-Galala, allows better understanding of the Middle Jurassic sea-level changes. It is established that the Bajocian-Bathonian relative sea-level changes in these areas were coherent. The magnitude of changes was lower in the Bajocian than in the Bathonian. Significant sea-level rises occurred at the Bajocian-Bathonian and middle-late Bathonian transitions, and there was a clear tendency toward sea-level rise throughout the studied time interval. This evidence favors one of the two alternative global eustatic reconstructions that implies "stable" position of the shoreline in the Bajocian and general tendency to eustatic rise throughout the Jurassic. The tectonic regime of northeastern Egypt in the Middle Jurassic provided for strong eustatic control of the relative sea-level changes. The possible influence of hotspot activity is questionable. Filling the accommodation space with materials derived from the eroded continent may explain some sea-level falls that are regionally documented.

  12. The impact of North Indian Ocean sea surface temperatures on the Indian summer monsoon

    NASA Astrophysics Data System (ADS)

    Levine, Richard; Turner, Andrew

    2010-05-01

    The relationship between sea surface temperature (SST) in the North Indian Ocean and Indian monsoon rainfall is investigated in both observational/re-analyses and climate model simulations. We focus on the partially land-enclosed Arabian Sea and Bay of Bengal, where SSTs are found to have significant correlations with All Indian Rainfall (AIR). This part of the Indian Ocean is therefore important for monsoon predictions, while this area tends to provide significant problems in coupled atmosphere-ocean model simulations. The observational variability of the SST-rainfall relationship is investigated on seasonal to decadal time-scales. This highlights a predominantly negative correlation over the monsoon trough area in North East India and a positive correlation over the rest of India, while these relationships are found to be weakened by the ENSO-monsoon teleconnection. Mechanisms are further investigated by performing a series of atmosphere-only model simulations using the Met Office Unified Model (MetUM). In these experiments we determine the response of the atmosphere to forced cold SST anomalies over isolated areas, which we also extend out into the equatorial Indian Ocean. The cold SSTs in the Arabian Sea and Bay of Bengal lead to a dramatic reduction in Indian rainfall, while cold biases in the equatorial Indian Ocean have the opposite effect, highlighting the competition between oceanic and continental Tropical Convergence Zones (TCZ). However, the impacts for the Arabian Sea and Bay of Bengal experiments are found to change between the pre-monsoon and post-monsoon onset periods.The impact on monsoon rainfall for cold SST biases in these regions is found to be the result of a balance between changes in regional low-level temperature gradients and the availability of moisture over the oceans, which determine the pathway of the monsoon jet and the moisture transport towards India. These experiments suggest that the intra-seasonal variability of the relationship

  13. Salt tectonics in the northeastern Nordkapp Basin, southwestern Barents Sea

    SciTech Connect

    Koyi, H.; Talbot, C.J.; Torudbakken, B.O.

    1996-12-31

    Salt structures in the northeastern Nordkapp subbasin are interpreted on reflection seismic profiles. Thickness variations indicate localized accumulation of the mother salt in Late Carboniferous-Early Permian time. Rapid sedimentation in the Early Triassic accompanied rise of salt into asymmetric salt pillows during regional extension. These pillows domed the prekinematic Permian sediments and became diapiric during the late Early-Middle Triassic, perhaps as a result of thin-skinned normal faulting decoupled by the salt from old basements faults reactivated by thick-skinned regional (northwest-southeast) extension. Variations in size, maturity, and evolution history of individual salt structures can be attributed to local differences in thickness of the initial salt layer and its burial history. Salt structures form three rows concentric to the basin margins and cover {approximately}20% of the basin area. Some salt stocks appear to overlie basement faults. Asymmetric primary, secondary, and in places tertiary, peripheral sinks indicate that salt was withdrawn mainly from the basin side of most diapirs throughout Triassic downbuilding.

  14. Mercury distribution in ancient and modern sediments of northeastern Bering Sea

    USGS Publications Warehouse

    Nelson, C. Hans; Pierce, D.E.; Leong, K.W.; Wang, F.F.

    1972-01-01

    A reconnaissance of surface and subsurface sediments to a maximum depth of 244 feet below the sea floor shows that natural mercury anomalies from 0.2 to 1.3 ppm have been present in northeastern Bering Sea since early Pliocene. The anomalies and mean values are highest in modern beach (maximum 1.3 and mean 0.22 ppm Hg) and nearshore subsurface gravels (maximum 0.6 and mean .06 ppm Hg) along the highly mineralized Seward Peninsula and in organic rich silt (maximum 0.16 and mean 0.10 ppm Hg) throughout the region; the mean values are lowest in offshore sands (0.03 ppm Hg) . Although gold mining may be partially responsible for high mercury levels in the beaches near Nome, Alaska, equally high or greater concentrations of mercury occur in ancient glacial sediments immediately offshore (0.6 ppm) and in modern unpolluted beach sediments at Bluff (0.45 - 1.3 ppm); this indicates that the contamination effects of mining may be no greater than natural concentration processes in the Seward Peninsula region. The background content of mercury (0.03) throughout the central area of northeastern Bering Sea is similar to that elsewhere in the world. The low mean values (0.04 ppm) even immediately offshore from mercury-rich beaches, suggests that in the surface sediments of northeastern Bering Sea, the highest concentrations are limited to the beaches near mercury sources; occasionally, however, low mercury anomalies occur offshore in glacial drift derived from mercury source regions of Chukotka and Seward Peninsula and reworked by Pleistocene shoreline processes. The minimal values offshore may be attributable to beach entrapment of heavy minerals containing mercury and/or dilution effects of modern sedimentation.

  15. Indian Ocean Dipole modulated wave climate of eastern Arabian Sea

    NASA Astrophysics Data System (ADS)

    Anoop, T. R.; Sanil Kumar, V.; Shanas, P. R.; Johnson, G.; Amrutha, M. M.

    2015-10-01

    Intrinsic modes of variability have a significant role in driving climatic oscillations in the ocean. In this paper, we investigate the influence of inter-annual variability, the Indian Ocean Dipole (IOD), on the wave climate of the eastern Arabian Sea (AS). Using measured, modeled and reanalysis wave data and reanalysis wind data, we show that the IOD plays a major role in the variability of wave climate of the study region due to the IOD induced changes in equatorial sea surface temperature and sea level pressure. Inter-annual variability in the wave climate over the eastern AS during the IOD is due to the modification of winds from the northern AS. The change in wind field over the AS due to IOD influences the generation or dissipation of wave field and hence causes the decrease in northwest short period waves during positive IOD and increase during negative IOD.

  16. Indian Ocean Dipole modulated wave climate of eastern Arabian Sea

    NASA Astrophysics Data System (ADS)

    Anoop, T. R.; Sanil Kumar, V.; Shanas, P. R.; Glejin, J.; Amrutha, M. M.

    2016-03-01

    Intrinsic modes of variability have a significant role in driving the climatic oscillations in the oceanic processes. In this paper, we investigate the influence of an inter-annual mode of variability, the Indian Ocean Dipole (IOD), on the wave climate of the eastern Arabian Sea (AS). Using measured, modeled and reanalysis wave data and reanalysis wind data, we show that the IOD plays a major role in the variability of wave climate of the study region. Due to the IOD-induced changes in equatorial sea surface temperature and sea level pressure, the winds from the northern AS gets modified and cause inter-annual variability in the wave climate over the eastern AS. The changes in wind field over the AS due to the IOD influence the generation or dissipation of the wave field and hence cause a decrease in northwest short-period waves during positive IOD and an increase during negative IOD.

  17. Structure and variability of the marine-bird community in the northeastern Chukchi Sea

    NASA Astrophysics Data System (ADS)

    Gall, Adrian E.; Day, Robert H.; Weingartner, Thomas J.

    2013-09-01

    We examined the seasonal and interannual variation in the marine-bird community and its relationship to physical oceanography in the northeastern Chukchi Sea in 2008-2010 as part of a multi-year, interdisciplinary study. We sampled 3 study areas, each ∼3000 km2, located in the offshore northeastern Chukchi Sea: Klondike, Burger, and Statoil. We quantified the marine habitat by measuring strength of stratification, depth of the mixed layer, and temperature and salinity in the upper mixed layer. The total density of seabirds was the highest in 2009, when warm (5-6 °C), moderately saline (31-31.5) Bering Sea Water (BSW) extended across Burger and Klondike at all depths. Bird density was generally higher in Klondike than in Burger in 2008 and 2009; densities did not differ significantly among study areas in 2010, when BSW covered all 3 study areas. The relative abundance of alcids in all study areas combined increased from 2008 to 2010. Klondike was numerically dominated by alcids and tubenoses in all years, whereas Burger was numerically dominated by larids and tubenoses in 2008 and by alcids in 2009 and 2010; Statoil also was numerically dominated by alcids in 2010. Least auklets, crested auklets, and northern fulmars were positively associated with strong stratification and high salinity (>31) in the upper mixed layer, characteristics that indicated the presence of BSW. Phalaropes were positively associated with salinity but negatively associated with stratification, suggesting that well-mixed water provides better foraging opportunities for these surface-feeding planktivores. The distribution and abundance of marine birds, particularly the planktivorous species, is influenced by advective processes that transport oceanic species of zooplankton from the Bering Sea to the Chukchi Sea. This transport apparently differed among years and resulted in a broader northeastward intrusion of Bering Sea Water and greater total abundance of planktivorous seabirds in the

  18. The relationship between Arabian Sea upwelling and Indian Monsoon revisited

    NASA Astrophysics Data System (ADS)

    Yi, Xing; Zorita, Eduardo; Hünicke, Birgit

    2015-04-01

    Coastal upwelling is important to marine ecosystems and human activities. It transports nutrient-rich deep water mass that supports marine biological productivity. In this study, we aim to characterize the large-scale climate forcings that drive upwelling along the western Arabian Sea coast. Studies based on ocean sediments suggest that there is a link between this coastal upwelling system and the Indian summer monsoon. However, a more direct method is needed to examine the influence of various forcings on upwelling. For this purpose, we analyse a high-resolution (about 10 km) global ocean simulation (denoted STORM), which is based on the MPI-OM model developed by the Max-Planck-Institute for Meteorology in Hamburg driven by the global meteorological reanalysis NCEP over the period 1950-2010. This very high spatial resolution allows us to identify characteristics of the coastal upwelling system. We compare the simulated upwelling velocity of STORM with two traditional upwelling indices: along-shore wind speed and sea surface temperature. The analysis reveals good consistency between these variables, with high correlations between coastal upwelling and along-shore wind speed (r=0.85) as well as coastal sea surface temperature (r=-0.77). To study the impact of the monsoon on the upwelling we analyse both temporal and spatial co-variability between upwelling velocity and the Indian summer monsoon index. The spatial analysis shows that the impact of the monsoon on the upwelling is concentrated along the coast, as expected. However, somewhat unexpectedly, the temporal correlation between the coastal upwelling and the monsoon index is rather weak (r=0.26). Also, the spatial structure of upwelling in the Arabian Sea as revealed by a Principal Component Analysis is rather rich, indicating that factors other than the Monsoon are also important drivers of upwelling. In addition, no detectable trend in our coastal upwelling is found in the simulation that would match the

  19. Sea-floor geology and topography offshore in northeastern Long Island Sound

    USGS Publications Warehouse

    Poppe, L.J.; McMullen, K.Y.; Ackerman, S.D.; Glomb, K.A.

    2013-01-01

    Datasets of gridded multibeam bathymetry, covering approximately 52.9 square kilometers, were used to interpret character and geology of the sea floor in northeastern Long Island Sound. Although originally collected for charting purposes during National Oceanic and Atmospheric Administration hydrographic survey H12012, these acoustic data and the sea-floor sampling and photography stations subsequently occupied to verify the acoustic data are interpreted (1) to define the composition and terrain of the seabed, (2) to provide information on sediment transport and benthic habitat, and (3) as part of an expanding series of studies that provide a fundamental framework for research and resource management (for example, cables, pipelines, and dredging) activities in this major east coast estuary.

  20. Modes of sedimentary basin formation in the north-eastern Black Sea

    NASA Astrophysics Data System (ADS)

    Stephenson, Randell; Starostenko, Vitaly; Sydorenko, Grygoriy; Yegorova, Tamara

    2016-04-01

    The Greater Caucasus and Black Sea sedimentary basins developed in a Mesozoic back-arc setting, the former older than the latter (Jurassic v. Cretaceous). Compressional shortening of the former and accompanying ongoing development of marginal basin depocentres in the north-eastern Black Sea - which is closely tied to the formation of the Crimea-Greater Caucasus orogen - is a Cenozoic phenomenon, starting in the Eocene and proceeding until the present day. Recently, the sedimentary basin/crust/lithosphere geometry of the study area has been characterised across a range of scales using regional seismic reflection profiling, long-offset refraction/wide-angle reflection profiling and local earthquake tomography. These provide a new integrated image of the present-day crustal structure and sedimentary basin architecture of the northern margin of the eastern Black Sea, north across the Azov Sea and provide evidence of the deeper expression of sedimentary basins and the processes controlling the geometry of their inversion during the Cenozoic. It is inferred that the Greater Caucasus paleo-Basin, lying stratigraphically below the Black Sea and younger sedimentary successions, extends further to the west than previously known. This basin has significant thickness in the area between the Azov and Black seas and probably forms the deeper core of the Crimea-Caucasus inversion zone. The Crimea-Greater Caucasus orogenic belt is the expression of "basin inversion" of the Jurassic Greater Caucasus paleo-Basin, the degree of inversion of which varies along strike. The Greater Caucasus foredeep basins - Indolo-Kuban and Sorokin-Tuapse troughs -represent syn-inversional marginal troughs to the main inversion zone. The Shatsky Ridge - the northern flank of the main East Black Sea Basin - may also be mainly a syn-inversional structure, underlain by a blind thrust zone expressed as a northward dipping zone of seismicity on the northern margin of the eastern Black Sea.

  1. Oysters, estuaries, and Late Pleistocene-Holocene sea level, northeastern Gulf of Mexico

    SciTech Connect

    Schroeder, W.W. . Marine Science Program); Shultz, A.W. )

    1993-03-01

    The timing and magnitude of global sea level fluctuations over the past 35 kyr remain nondum ostenduntur after three decades of study. The construction of local relative sea level histories is often complicated by the need to assess regional tectonic and climatic components together. The authors attempt to contribute to an understanding of sea level fluctuations in the northeastern Gulf of Mexico through the application of faunal tracking, using fossil oyster shells as indicators of paleoestuarine environments. They assume that sites on the continental shelf where oysters have been collected were coastal and therefore are reasonable approximations of past shoreline locations and sea-level elevations. They acknowledge that this assumption is a leap of faith for some observers, but is justified as a provisional step toward an independent determination. Insights into Quaternary coastal paleogeography are gathered from locations and radiocarbon ages of American oyster (Crassostrea virginica) shells collected from the Alabama continental shelf. Prior to the onset of the last Wisconsinan glaciation (35 to 26 kyr BP), estuaries occupied a zone 20 to 25 km seaward of today's coastline. As glaciation increased and sea level was lowered (23 to 21 kyr BP), open coastal estuarine conditions developed southward. Oysters dating from the lowstand period (20 to 16 kyr BP) have not been collected. As sea level rose over the next 10 kyr (16 to 6 kyr BP), estuaries were displaced northward in steps. This data on depths and ages can be viewed as supporting an interpretation of fluctuating Holocene sea level, rather than a steady sea-level rise.

  2. Marine mammal acoustic detections in the northeastern Chukchi Sea, September 2007-July 2011

    NASA Astrophysics Data System (ADS)

    Hannay, David E.; Delarue, Julien; Mouy, Xavier; Martin, Bruce S.; Leary, Del; Oswald, Julie N.; Vallarta, Jonathan

    2013-09-01

    Several cetacean and pinniped species use the northeastern Chukchi Sea as seasonal or year-round habitat. This area has experienced pronounced reduction in the extent of summer sea ice over the last decade, as well as increased anthropogenic activity, particularly in the form of oil and gas exploration. The effects of these changes on marine mammal species are presently unknown. Autonomous passive acoustic recorders were deployed over a wide area of the northeastern Chukchi Sea off the coast of Alaska from Cape Lisburne to Barrow, at distances from 8 km to 200 km from shore: up to 44 each summer and up to 8 each winter. Acoustic data were acquired at 16 kHz continuously during summer and on a duty cycle of 40 or 48 min within each 4-h period during winter. Recordings were analyzed manually and using automated detection and classification systems to identify calls. Bowhead (Balaena mysticetus) and beluga (Delphinapterus leucas) whale calls were detected primarily from April through June and from September to December during their migrations between the Bering and Beaufort seas. Summer detections were rare and usually concentrated off Wainwright and Barrow, Alaska. Gray (Eschrichtius robustus) whale calls were detected between July and October, their occurrence decreasing with increasing distance from shore. Fin (Balaenoptera physalus), killer (Orcinus orca), minke (Balaenoptera acutorostrata), and humpback (Megaptera novaeangliae) whales were detected sporadically in summer and early fall. Walrus (Odobenus rosmarus) was the most commonly detected species between June and October, primarily occupying the southern edge of Hanna Shoal and haul-outs near coastal recording stations off Wainwright and Point Lay. Ringed (Pusa hispida) and bearded (Erignathus barbatus) seals occur year-round in the Chukchi Sea. Ringed seal acoustic detections occurred throughout the year but detection numbers were low, likely due to low vocalization rates. Bearded seal acoustic detections

  3. Sea-floor geology in northeastern Block Island Sound, Rhode Island

    USGS Publications Warehouse

    McMullen, Kate Y.; Poppe, Lawrence J.; Ackerman, Seth D.; Blackwood, Dann S.; Lewit, P.G.; Parker, Castle E.

    2013-01-01

    Multibeam-echosounder and sidescan-sonar data collected by the National Oceanic and Atmospheric Administration in northeastern Block Island Sound, combined with sediment samples and bottom photography collected by the U.S. Geological Survey, are used to interpret sea-floor features and sedimentary environments in this 52-square-kilometer-area offshore Rhode Island. Boulders, which are often overgrown with sessile fauna and flora, are mostly in water depths shallower than 20 meters. They are probably part of the southern flank of the Harbor Hill-Roanoke Point-Charlestown-Buzzards Bay moraine, deposited about 18,000 years ago. Scour depressions, areas of the sea floor with a coarser grained, rippled surface lying about 0.5 meter below the finer grained, surrounding sea floor, along with erosional outliers within the depressions are in a band near shore and also offshore in deep parts of the study area. Textural and bathymetric differences between areas of scour depressions and the surrounding sea floor or erosional outliers stand out in the sidescan-sonar imagery with sharp tonal contrasts. Also visible in the sidescan-sonar imagery are broad, low-profile bedforms with coarser grained troughs and finer grained crests.

  4. The offshore northeastern Chukchi Sea, Alaska: A complex high-latitude ecosystem

    NASA Astrophysics Data System (ADS)

    Day, Robert H.; Weingartner, Thomas J.; Hopcroft, Russell R.; Aerts, Lisanne A. M.; Blanchard, Arny L.; Gall, Adrian E.; Gallaway, Benny J.; Hannay, David E.; Holladay, Brenda A.; Mathis, Jeremy T.; Norcross, Brenda L.; Questel, Jennifer M.; Wisdom, Sheyna S.

    2013-09-01

    We conducted an interdisciplinary ecological study in and near 3 nearby proposed exploratory oil and gas prospects in the offshore northeastern Chukchi Sea during the open-water seasons of 2008-2010. This region exhibits a classical pelagic-benthic dichotomy of food-web structure in ecological function. The Klondike study area borders the eastern edge of the Central Channel and functions as a pelagic-dominated ecosystem, whereas the Burger study area lies south of Hanna Shoal and functions as a benthic-dominated ecosystem. The Statoil study area, which is located north of Klondike and northwest of Burger, has both pelagic and benthic attributes, although it is more like Burger than like Klondike. Klondike has lower benthic density and biomass, a higher biomass of oceanic zooplankton, and more fishes and planktivorous seabirds than does Burger, which has benthic communities with high density and biomass, primarily neritic zooplankton, and higher densities of benthic-feeding marine mammals than Klondike; Statoil has characteristics of both ecosystems. Patterns of sea-ice retreat vary interannually; in some years, much of the northeastern Chukchi is ice-free by mid-May, leading to pelagic and ice-edge phytoplankton blooms, whereas heavy ice cover in other years leads to substantial within-ice production. The characteristics of this region during the open-water season are not consistent among years, in that Bering Sea Water impinges onto all study areas only in some years, resulting in interannual variation in the distribution and abundance of zooplankton, planktivorous seabirds, and pelagic-feeding seals. These interannual variations alter several aspects of this pelagic-benthic dichotomy, and some aspects of this region suggest unusual structure (e.g., replacement of benthic-feeding fishes in some areas by predatory invertebrates, a lack of benthic-feeding seaducks).

  5. Interannual Indian rainfall variability and Indian Ocean sea surface temperature anomalies

    NASA Astrophysics Data System (ADS)

    Vecchi, Gabriel A.; Harrison, D. E.

    It is shown that interannual variations in Indian continental rainfall during the southwest monsoon can be usefully represented by two regional rainfall indices. Indian rainfall is concentrated in two regions, each with strong mean and variance in precipitation: the Western Ghats (WG) and the Ganges-Mahanadi Basin (GB) region. Interannual variability of rainfall averaged over each of the two regions (WG and GB) is uncorrelated; however, the rainfall over these two regions together explains 90% of the interannual variance of All-India rainfall (AIR). The lack of correlation between WG and GB rainfall suggests that different mechanisms may account for their variability. During the period 1982-2001, rainfall variability over each of these two regions exhibits distinct relationships to Indian Ocean SST: warm SSTA over the western Arabian Sea at the monsoon onset is associated with increased WG rainfall (r = 0.77), while cool SSTA off of Java and Sumatra is associated with increased GB rainfall (r = -0.55). The connection between SSTA and AIR is considerably weaker, and represents the superposition of that associated with each region. We find the relationship with WG rainfall is robust, while that with GB results from a single exceptional year. Each region also exhibits distinct relationships to El Niño SSTA indices.

  6. The relationship between Arabian Sea upwelling and Indian monsoon revisited

    NASA Astrophysics Data System (ADS)

    Yi, X.; Hünicke, B.; Tim, N.; Zorita, E.

    2015-11-01

    Studies based on upwelling indices (sediment records, sea-surface temperature and wind) suggest that upwelling along the western coast of Arabian Sea is strongly affected by the Indian summer monsoon (ISM). In order to examine this relationship directly, we employ the vertical water mass transport produced by the eddy-resolving global ocean simulation STORM driven by meteorological reanalysis over the last 61 years. With its very high spatial resolution (10 km), STORM allows us to identify characteristics of the upwelling system. We analyze the co-variability between upwelling and meteorological and oceanic variables from 1950 to 2010. The analyses reveal high interannual correlations between coastal upwelling and along-shore wind-stress (r=0.73) as well as with sea-surface temperature (r0.83). However, the correlation between the upwelling and the ISM is small and other factors might contribute to the upwelling variability. In addition, no long-term trend is detected in our modeled upwelling time series.

  7. 77 FR 76950 - Fisheries of the Northeastern United States; Summer Flounder, Scup, and Black Sea Bass Fisheries...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-31

    ... 23, 2012 (77 FR 24151). An error was found in the summer flounder commercial quota and recreational... Register of April 23, 2012, in FR Doc. 2012-9755, on page 24152, Table 1 is corrected as follows: Table 1... Northeastern United States; Summer Flounder, Scup, and Black Sea Bass Fisheries; 2012 Summer Flounder,...

  8. Phenotypic and genetic characterization of bacteria isolated from diseased cultured sea cucumber (Apostichopus japonicus) in Northeastern China

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During the winter–spring from 2004 to 2006 in northeastern China cultured Japanese sea cucumber Apostichopus japonicus suffered from a serious disease. Clinical signs included swollen mouth, skin ulceration and massive mortality. Clinical samples taken during this period were studied. Thirty-one bac...

  9. Effects of warm Arabian Sea Surface Temperature on the Summer Monsoon over Peninsular Indian Region

    NASA Astrophysics Data System (ADS)

    Janardanan, Rajesh; Mohanakumar, Kesavapillai; Rajanayagam, Lorna

    This study investigates the characteristics of circulation and precipitation during monsoon season over peninsular Indian region, based on the sensitivity experiments performed by a regional climate model for the year 2002. The present study uses a recent version (Version-III) of National Center for Atmospheric Research (NCAR) Regional Climate Model (RegCM3). The planetary boundary layer scheme used is that of Holtslag, cumulus parameterization scheme Emanuel of MIT, SUBEX large scale precipitation scheme and BATS ocean flux parameterization scheme. The model is run from 1st May to 30th September. The first month is taken for the spin up. The next four months are taken to study the monsoon. RegCM3 has been integrated at 60 km horizontal resolution over the Indian domain. The experiments are carried out by changing the initial conditions of Sea Surface Temperature by 0.1 degree steps ie. 0.1, 0.2 etc. to 1 degree maximum. The sensitivity experiments showed that the wind strength increases significantly to the northeastern and central parts of India. The change in wind strength is pronounced over the southern peninsula when the Sea Surface Temperature increased by 0.4 degree. The response in precipitation over the peninsular Indian region is also studied. The monsoon circulation features simulated by RegCM3 are compared with those of the NCEP/NCAR reanalysis and the simulated rainfall is validated against observations from the Global Precipitation Climatology Centre (GPCC) Key words:- Peninsular India, model integration, Monsoon Rainfall Reference: K. C. chow, Yiming Liu, Johnny C. L. Chan and Yihui Ding, Int. J. Climatol. 26: 1339-1359 (2006) K. C. Chow, Hang-Wai Tong and Johnny C. L. Chan, Clim. Dyn. DOI 10.1007/s00382-007- 0301-6 G. P. Singh, Jai-Ho Oh, Jin-Young Kim and Ok-Yeon Kim; ", SOLA, Vol. 2, pp.29-32 (2006) Dash S. K., Shekhar M. S., Singh G. P. Theoretical and Applied Climatology 86(1-4): 161 (2006)

  10. Aerosol lofting from sea breeze during the Indian Ocean Experiment

    NASA Astrophysics Data System (ADS)

    Verma, S.; Boucher, O.; Venkataraman, C.; Reddy, M. S.; Müller, D.; Chazette, P.; Crouzille, B.

    2006-04-01

    This work was carried out to understand the mechanisms leading to lofting and large-scale advection of aerosols over the Indian Ocean region due to interaction of the sea breeze with the northeast monsoon winds along the west coast of India. European Centre for Medium-Range Weather Forecasts (ECMWF) wind fields for the months of February and March 1999 were analyzed at various times of day. Intense sea breeze activity was observed at 1200 UT (1730 local time) along the west coast of India with average intensity larger in March than in February. The sea breeze was seen to extend inland deeper in March than in February. Lofting of air observed as high as 800 hPa (approximately 2 km above sea level) could lead to entrainment of aerosols into the free troposphere and long-range transport. Upward motion of air was observed everywhere along the west coast of India (from 8° to 20°N), on average higher in March than in February, because of convergence between the sea breeze and the synoptic-scale flow. A region of intense lofting of air and well-defined convergence was observed along the coast of the Karnataka region (12°-16°N). A simulation with a general circulation model nudged with ECMWF data indicated that the intrusion of marine air masses with low concentrations of organic matter is seen as deep as 64 km inland in the evening (1500 UT). Intrusion of the sea-salt plume is seen to a maximum distance of around 200 km from 1500 until 2300 UT. A well-developed lofted layer of aerosols as high as 3 km was also simulated during sea breeze activity along the west coast of India. The general circulation model simulation shows a clear diurnal evolution of the vertical profile of the aerosol extinction coefficient at Goa but fails to reproduce several features of the lidar observations, for example, the marked diurnal variability of the upper layers between 1 and 3 km. However, the model simulates a diurnal cycle at the surface (0-0.7 km) that is not apparent in lidar

  11. Effects of produced waters at oilfield production sites on the Osage Indian Reservation, northeastern Oklahoma

    USGS Publications Warehouse

    Otton, James K.; Asher-Bolinder, Sigrid; Owen, Douglass E.; Hall, Laurel

    1997-01-01

    The authors conducted limited site surveys in the Wildhorse and Burbank oilfields on the Osage Indian Reservation, northeastern Oklahoma. The purpose was to document salt scarring, erosion, and soil and water salinization, to survey for radioactivity in oilfield equipment, and to determine if trace elements and naturally occurring radioactive materials (NORM) were present in soils affected by oilfield solid waste and produced waters. These surveys were also designed to see if field gamma spectrometry and field soil conductivity measurements were useful in screening for NORM contamination and soil salinity at these sites. Visits to oilfield production sites in the Wildhorse field in June of 1995 and 1996 confirmed the presence of substantial salt scarring, soil salinization, and slight to locally severe erosion. Levels of radioactivity on some oil field equipment, soils, and road surfaces exceed proposed state standards. Radium activities in soils affected by tank sludge and produced waters also locally exceed proposed state standards. Laboratory analyses of samples from two sites show moderate levels of copper, lead, and zinc in brine-affected soils and pipe scale. Several sites showed detectable levels of bromine and iodine, suggesting that these trace elements may be present in sufficient quantity to inhibit plant growth. Surface waters in streams at two sampled sites exceed total dissolved solid limits for drinking waters. At one site in the Wildhorse field, an EM survey showed that saline soils in the upper 6m extend from a surface salt scar downvalley about 150 m. (Photo [95k]: Dead oak trees and partly revegetated salt scar at Site OS95-2 in the Wildhorse field, Osage County, Oklahoma.) In the Burbank field, limited salt scarring and slight erosion occurs in soils at some sites and low to moderate levels of radioactivity were observed in oil field equipment at some sites. The levels of radioactivity and radium observed in some soils and equipment at these

  12. Distortion and broadening of internal solitary wavefront in the northeastern South China Sea deep basin

    NASA Astrophysics Data System (ADS)

    Xie, Jieshuo; He, Yinghui; Lü, Haibin; Chen, Zhiwu; Xu, Jiexin; Cai, Shuqun

    2016-07-01

    Internal solitary waves (ISWs) with peculiar fronts are frequently observed in the world ocean by satellite images, though with quite few explanations. In this study a distorted and broadening ISW front across the northeastern South China Sea deep basin is presented by using synthetic aperture radar (SAR) image. To illustrate this peculiar front, a nonlinear refraction model is developed to simulate and evaluate the effects of realistic bottom topography, current, and stratification on its transformation. Simulated results in realistic oceanic environments show good agreements with this SAR-observed front. Based on separate and comparative results in different background environments, we demonstrate that the distortion is actually caused by the strong mesoscale currents at periphery of an anticyclonic eddy. Moreover, the broadening is due to the difference in change of wave half width at different rays, which is associated with the different transformation of ISWs across variable bottom topography in the deep basin.

  13. Sediment deformation related to the submarine failure in northeastern South China Sea continental margin

    NASA Astrophysics Data System (ADS)

    Chiu, J.

    2012-12-01

    In northeastern South China Sea continental margin, geological structure is complex due to the passive continental margin meets the Taiwan mountain belt. Submarine slope failures, turbidity flows and so on are the main sedimentary processes in this continental slope, but these processes play different roles along the passive continental slope. So Chirp subbottom profiles, include analog and digital data, and cores collected in this region were analyzed to study the difference of sedimentation of the Late Quaternary. We found that more sediment deformations near seafloor, e.g. sediment layer pulled by sliding block and formed a shape like "pinch-out", were observed in the west region of the study area. This phenomenon could be related to finer sediments from mainland China, comparing with coarser sediments from Taiwan mountain belt deposited in the east region of the study area.

  14. Temporal record of Pu isotopes in inter-tidal sediments from the northeastern Irish Sea.

    PubMed

    Lindahl, Patric; Worsfold, Paul; Keith-Roach, Miranda; Andersen, Morten B; Kershaw, Peter; Leonard, Kins; Choi, Min-Seok; Boust, Dominique; Lesueur, Patrick

    2011-11-01

    A depth profile of (239)Pu and (240)Pu specific activities and isotope ratios was determined in an inter-tidal sediment core from the Esk Estuary in the northeastern Irish Sea. The study site has been impacted with plutonium through routine radionuclide discharges from the Sellafield nuclear reprocessing plant in Cumbria, NW England. A pronounced sub-surface maximum of ~10 k Bq kg(-1) was observed for (239+240)Pu, corresponding to the peak in Pu discharge from Sellafield in 1973, with a decreasing trend with depth down to ~0.04 k Bq kg(-1) in the deeper layers. The depth profile of (239+240)Pu specific activities together with results from gamma-ray spectrometry for (137)Cs and (241)Am was compared with reported releases from the Sellafield plant in order to estimate a reliable sediment chronology. The upper layers (1992 onwards) showed higher (239+240)Pu specific activities than would be expected from the direct input of annual Sellafield discharges, indicating that the main input of Pu is from the time-integrated contaminated mud patch of the northeastern Irish Sea. The (240)Pu/(239)Pu atom ratios ranged from ~0.03 in the deepest layers to >0.20 in the sub-surface layers with an activity-weighted average of 0.181. The decreasing (240)Pu/(239)Pu atom ratio with depth reflects the changing nature of operations at the Sellafield plant from weapons-grade Pu production to reprocessing spent nuclear fuel with higher burn-up times in the late 1950s. In addition, recent annual (240)Pu/(239)Pu atom ratios in winkles collected during 2003-2008 from three stations along the Cumbrian coastline showed no significant spatial or temporal differences with an overall average of 0.204, which supports the hypothesis of diluted Pu input from the contaminated mud patch. PMID:21911246

  15. Seismic interpretation of the post-Middle Miocene section of the northeastern Northern South Sea Yellow Basin, Yellow Sea

    NASA Astrophysics Data System (ADS)

    Kim, Hyeonju; Lee, Gwang H.; Kim, Han J.; Yi, BoYeon

    2016-04-01

    The Yellow Sea is a very shallow (< 90 m), semi-enclosed epicontinental sea, lying between China and the Korean Peninsula. The Yellow Sea has undergone gradual, regional subsidence since the Middle Miocene when the major plate reorganization in East Asia led to regional uplift and subsequent erosion in many parts of the marginal basins of the western Pacific, including the Yellow Sea. In this study, we analyzed about 2500 km of 2-D multi-channel seismic data from the northeastern part of the Northern South Yellow Sea Basin to investigate the post-Middle Miocene geologic history of the area. We identified and mapped the Middle Miocene unconformity (MMU) and two horizons (H1 and H2) which are correlatable over much of the area. H1 and H2 were inferred to be of the early Late Miocene (ca. 10 Ma) and of the late Late Miocene (ca. 6.7 Ma), respectively, assuming a constant sediment accumulation rate. MMU forms the top of the basement except for the southwestern corner of the area and is interrupted by numerous volcanic bodies, suggesting active post-Middle Miocene volcanism. The volcanic bodies are oriented largely parallel to the basement faults. H1 and H2 are also affected by volcanic bodies in the northern part of the area, suggesting continued volcanism until the late Late Miocene. The depth of MMU increases southwestward from about 250 m to over 750 m, indicating progressive tilting (i.e., differential subsidence) of the basement toward the depocenter in the southwest. The depths of H1 and H2 increase west- and southwestward from about 200 m to over 450 m and from about 150 m to over 300 m, respectively. Detailed seismic facies were not analyzed due to poor data quality; nevertheless, continuous reflectors, suggesting uniform and thus marine deposition, appear to increase upward and northeastward. This, together with the amount of subsidence estimated from the depth of MMU, strongly suggests that subsidence has been dominant in the area over the global sea

  16. Interannual variability of the Indian summer monsoon associated with the air-sea feedback in the northern Indian Ocean

    NASA Astrophysics Data System (ADS)

    Shukla, Ravi P.; Huang, Bohua

    2016-03-01

    Using observation-based analyses, this study identifies the leading interannual pattern of the Indian summer monsoon rainfall (ISMR) independent of ENSO and examines the potential mechanisms of its formation. For this purpose, an objective procedure is used to isolate the variability of the summer precipitation associated with the contemporary ENSO state and in previous winter-spring, which influence the Indian summer monsoon (ISM) region in opposite ways. It is shown that the leading pattern of these ENSO-related monsoon rainfall anomalies reproduces some major ISMR features and well represents its connections to the global-scale ENSO features in both lower and upper troposphere. On the other hand, the leading pattern derived from the precipitation anomalies with the ENSO component removed in the ISM and surrounding region also accounts for a substantial amount of the monsoon precipitation centered at the eastern coast of the subtropical Arabian Sea, extending into both the western Indian Ocean and the Indian subcontinent. The associated atmospheric circulation change is regional in nature, mostly confined in the lower to mid troposphere centered in the Arabian Sea, with a mild connection to an opposite tendency centered at the South China Sea. Further analyses show that this regional pattern is associated with a thermodynamic air-sea feedback during early to mid summer season. Specifically, before the monsoon onset, an anomalous atmospheric high pressure over the Arabian Sea causes excessive shortwave radiation to the sea surface and increases SST in May. The warm SST anomalies peak in June and reduce the sea level pressure. The anomalous cyclonic circulation generates regional convection and precipitation, which also induces subsidence and anticyclonic circulation over the South China Sea. The combined cyclonic-anticyclonic circulation further transport moisture from the western Pacific into the Indian Ocean and causes its convergence into the Arabian Sea. As a

  17. Pollen evidence for late pleistocene bering land bridge environments from Norton Sound, Northeastern Bering Sea, Alaska

    USGS Publications Warehouse

    Ager, T.A.; Phillips, R.L.

    2008-01-01

    After more than half a century of paleoenvironmental investigations, disagreements persist as to the nature of vegetation type and climate of the Bering land bridge (BLB) during the late Wisconsin (Sartan) glacial interval. Few data exist from sites on the former land bridge, now submerged under the Bering and Chukchi Seas. Two hypotheses have emerged during the past decade. The first, based on pollen data from Bering Sea islands and adjacent mainlands of western Alaska and Northeast Siberia, represents the likely predominant vegetation on the Bering land bridge during full-glacial conditions: graminoid-herb-willow tundra vegetation associated with cold, dry winters and cool, dry summer climate. The second hypothesis suggests that dwarf birch-shrub-herb tundra formed a broad belt across the BLB, and that mesic vegetation was associated with cold, snowier winters and moist, cool summers. As a step towards resolving this controversy, a sediment core from Norton Sound, northeastern Bering Sea was radiocarbon dated and analyzed for pollen content. Two pollen zones were identified. The older, bracketed by radiocarbon ages of 29,500 and 11,515 14C yr BP, contains pollen assemblages composed of grass, sedge, wormwood, willow, and a variety of herb (forb) taxa. These assemblages are interpreted to represent graminoid-herb-willow tundra vegetation that developed under an arid, cool climate regime. The younger pollen zone sediments were deposited about 11,515 14C yr BP, when rising sea level had begun to flood the BLB. This younger pollen zone contains pollen of birch, willow, heaths, aquatic plants, and spores of sphagnum moss. This is interpreted to represent a Lateglacial dwarf birch-heath-willow-herb tundra vegetation, likely associated with a wetter climate with deeper winter snows, and moist, cool summers. This record supports the first hypothesis, that graminoid-herb-willow tundra vegetation extended into the lowlands of the BLB during full glacial conditions of the

  18. Tetrodotoxin levels in pufferfish (Lagocephalus sceleratus) caught in the Northeastern Mediterranean Sea.

    PubMed

    Kosker, Ali Rıza; Özogul, Fatih; Durmus, Mustafa; Ucar, Yılmaz; Ayas, Deniz; Regenstein, Joe M; Özogul, Yesim

    2016-11-01

    The toxicity of tetrodotoxin (TTX) in pufferfish (Lagocephalus sceleratus) from Mersin Bay in the Northeastern Mediterranean Sea was measured using a mouse bioassay (MBA) and LC-MS-MS. Pufferfish were caught by trawl fishing, longlining and fishing line from December 2012 to October 2013. Changes in the levels of TTX in the gonads, livers, intestines, skins and muscles as a function of season and sex were determined. The gonads of female fish were toxic in all seasons (>2μg/g), whereas the gonads of male fish were only toxic in the spring and autumn. The highest TTX levels in gonads, livers, intestines and skins of female fish were 52.1, 46.2, 7.64 and 3.43μg/g, respectively, using LC-MS-MS. The TTX level in the muscle of female fish in winter was 2.83μg/g but was otherwise below the toxic limit. Consequently, it can be dangerous to consume pufferfish, including the edible muscle, from the Eastern Mediterranean Sea. PMID:27211655

  19. Annual cycle of zooplankton abundance and species composition in Izmit Bay (the northeastern Marmara Sea)

    NASA Astrophysics Data System (ADS)

    Isinibilir, Melek; Kideys, Ahmet E.; Tarkan, Ahmet N.; Yilmaz, I. Noyan

    2008-07-01

    The monthly abundance, biomass and taxonomic composition of zooplankton of Izmit Bay (the northeastern Marmara Sea) were studied from October 2001 to September 2002. Most species within the zooplankton community displayed a clear pattern of succession throughout the year. Generally copepods and cladocerans were the most abundant groups, while the contribution of meroplankton increased at inner-most stations and dominated the zooplankton. Both species number ( S) and diversity ( H') were positively influenced by the increase in salinity of upper layers ( r = 0.30 and r = 0.31, p < 0.001, respectively), while chlorophyll a was negatively affected ( r = -0.36, p < 0.001). Even though Noctiluca scintillans had a significant seasonality ( F11,120 = 8.45, p < 0.001, ANOVA), abundance was not related to fluctuations in temperature and only chlorophyll a was adversely correlated ( r = -0.35, p < 0.001). In general, there are some minor differences in zooplankton assemblages of upper and lower layers. A comparison of the species composition and abundance of Izmit Bay with other Black Sea bays reveals a high similarity between them.

  20. Northeastern Chukchi Sea demersal fishes and associated environmental characteristics, 2009-2010

    NASA Astrophysics Data System (ADS)

    Norcross, Brenda L.; Raborn, Scott W.; Holladay, Brenda A.; Gallaway, Benny J.; Crawford, Stephen T.; Priest, Justin T.; Edenfield, Lorena E.; Meyer, Robert

    2013-09-01

    Three closely-spaced study areas in the northeastern Chukchi Sea off of Alaska provided a opportunity to examine demersal fish communities over a small spatial scale as part of a multidisciplinary program. During 2009 and 2010, fishes in the three study areas (Klondike, Burger, and Statoil) were sampled at 37 stations with a plumb staff beam trawl and a 3 m beam trawl; 70% of stations were sampled during all three cruises. Fish catches were dominated by small fishes (<150 mm TL), which cannot be wholly attributed to the small mesh size of the net. Output from generalized linear modeling of the data suggested that overall fish density, species richness, and density of Arctic staghorn sculpin (Gymnocanthus tricuspis) and Bering flounder (Hippoglossoides robustus) were higher in the more southerly Klondike study area than in the more northerly Burger and Statoil study areas. Arctic cod (Boreogadus saida) was abundant throughout the study region. Richness and density could be explained by the environmental variables that defined the overall study area. The Klondike study area was warmer and erosional in nature with higher proportions of gravel sediment. Other study areas were colder and more depositional in nature with muddier sediment and were characterized by high densities of megafaunal invertebrates such as brittle stars. There appeared to be a lack of ecological homogeneity across these three closely-spaced study areas of the Chukchi Sea.

  1. Late Holocene SST and primary productivity variations in the northeastern Arabian Sea as a recorder for winter monsoon variability

    NASA Astrophysics Data System (ADS)

    Böll, Anna; Gaye, Birgit; Lückge, Andreas

    2014-05-01

    Variability in the oceanic environment of the Arabian Sea region is strongly influenced by the seasonal monsoon cycle of alternating wind directions. Strong south-westerly winds during the summer monsoon induce upwelling of nutrient rich waters along the coast off Somalia, Oman and southwest India, which result in high rates of primary production. In the northeastern Arabian Sea off Pakistan on the other hand, primary production and sea surface temperatures are linked to northeast monsoonal winds that cool the sea surface and drive convective mixing and high surface ocean productivity during the winter season. In this study, we analyzed alkenone-derived sea surface temperature (SST) variations and proxies of primary productivity (organic carbon and δ15N) in a well-laminated sediment core from the Pakistan continental margin to establish the first high-resolution record of winter monsoon variability for the late Holocene. Over the last 2400 years reconstructed SST in the northeastern Arabian Sea decreased whereas productivity increased, imaging a long-term trend of northeast monsoon strengthening in response to insolation-induced southward migration of the Intertropical Convergence Zone. The comparison of our winter monsoon record with records of summer monsoon intensity suggests that summer and winter monsoon strength was essentially anti-correlated over the late Holocene throughout the Asian monsoon system. In addition, SST variations recorded off Pakistan match very well with Northern Hemisphere temperature records supporting the growing body of evidence that Asian climate is linked to Northern Hemisphere climate change. It reveals a consistent pattern of increased summer monsoon activity in the northeastern Arabian Sea during northern hemispheric warm periods (Medieval Warm Period, Roman Warm Period) and strengthened winter monsoon activity during hemispheric colder periods (Little Ice Age).

  2. Rates of nitrification and ammonium dynamics in northeastern Chukchi Sea shelf waters

    NASA Astrophysics Data System (ADS)

    Souza, Afonso C.; Gardner, Wayne S.; Dunton, Kenneth H.

    2014-04-01

    Nutrient concentrations are often depleted in surface waters during the late summer open-water period in the northern Chukchi Sea. Yet the rate of re-supply of nutrients to the pelagic environment controls phytoplankton community abundance and productivity, which in turn influences the benthic components of this relatively shallow ecosystem. We measured nitrogen cycling rates at four experimental stations on the northeastern Chukchi Sea shelf in the western arctic. At each station, rates for net NH4+ regeneration, actual NH4+ uptake, and nitrification were measured using 15N isotope enrichment methods with 24-h bottle incubations under both light and dark conditions. Net NH4+ regeneration rates throughout the water column ranged between -0.25 and 0.23 μmol N L-1 h-1, with highest net positive regeneration occurring under light exposure in surface waters. Actual uptake rates ranged between -0.41 and -0.01 μmol N L-1 h-1. Nitrification rates (measured at two stations) were generally highest in the sediment overlying waters, ranging between 0.14 and 0.67 μmol N L-1 h-1, and appear to account for most NH4+ uptake. Calculations of turnover time indicate that N is recycled within one day throughout the water column under natural conditions in the northern Chukchi Sea. Our findings confirm the results of previous studies that suggest a significant portion of surface nutrients on the Chukchi Shelf are products of horizontal advection through the Anadyr Current but also highlight the role of sediment regenerated N in supporting water-column primary production.

  3. Perkinsosis in the clams Ruditapes decussatus and R. philippinarum in the Northeastern Atlantic and Mediterranean Sea: A review.

    PubMed

    Ruano, Francisco; Batista, Frederico M; Arcangeli, Giuseppe

    2015-10-01

    Perkinsosis is a disease of gastropod and bivalve molluscs caused by protozoan parasites of the Perkinsus genus. These parasites have been responsible for mass mortalities worldwide, with a significant impact in both fisheries and aquaculture, and resulting in severe economic losses. This review focuses mainly on current knowledge of diagnostic methods and on the distribution of Perkinsus spp. in the Northeastern Atlantic and Mediterranean Sea, which infect the grooved carpet shell clam Ruditapes decussatus and the Japanese carpet shell clam Ruditapes philippinarum. The association between perkinsosis and high mortality rates of R. decussatus and R. philippinarum in southern European countries such as Portugal and Italy is discussed as is the role of environmental factors in those mortality outbreaks. The putative introduction of Perkinsus olseni into the Northeastern Atlantic and Mediterranean Sea is also discussed, as are management strategies that could be used to mitigate the impact of perkinsosis in production of R. decussatus and R. philippinarum. PMID:26239015

  4. Comparative study of the hydrochemical regime in the Gelendzhik and Golubaya Bays, northeastern Black Sea

    NASA Astrophysics Data System (ADS)

    Kostyleva, A.; Chasovnikov, V.; Chjoo, V.; Menshikova, N.; Kuprikova, N.

    2009-04-01

    The goal of this work was to study the hydrochemical regime in the coastal waters of the northeastern Black Sea. The observations were performed in influenced by significant anthropogenic stress Gelendzhik Bay and at the open coast region (Golubaya Bay). A sampling program has been initiated by the Southern Branch of Shirshov Institute of Oceanology, RAS, (SB SIO RAS) on a weekly basis at the shore line area of «Chernomorets» beach (Gelendzhik Bay) and from the head of pier in the Golubaya Bay. Studies were carried out during a period from January 2001 to December 2008. List of measured parameters includes following: temperature, salinity, dissolved oxygen, biological oxygen demand (BOD), pH, alkalinity, phosphate, organic phosphorus, silicates, nitrates, nitrites, ammonia, urea, organic nitrogen, oil products. The Gelendzhik bay in its different parts is characterized with strong variability of concentrations of hydrochemical parameters. Above all, it relates to complex structure caused by wind impact. Parts of the bay filled with nearshore and sea waters are legibly differ from each other. The bay itself is rather isolated from the open sea, and its liability to man's impact leads to forming of next features of its seasonal variability of physical-chemical state: • On the base of Si/P and Si/N ratios analysis it was shown that the Gelendzhik Bay waters are significantly enriched with nitrogen and phosphorus compounds. • Unlike the Golubaya bay, phosphates are always present in the water of the Gelendzhik Bay and development of photosynthesis is not limited with nutrients. It may lead to processes of intensive eutrophication. • The oxygen saturation in the Gelendzhik Bay periodically descend lower than 80% during the summer period. That means, that even the Bay's surface layer formally corresponds to the hypoxic conditions that testify to the degradation of the ecosystem there. The conclusions obtained during our studies testify that the pollution from

  5. Multidisciplinary experiment on studying short-period variability of the sedimentary process in the northeastern part of the Black Sea

    NASA Astrophysics Data System (ADS)

    Klyuvitkin, A. A.; Ostrovskii, A. G.; Novigatskii, A. N.; Lisitzin, A. P.

    2016-07-01

    The principal aim of this work is to reveal the regularities of short-period synoptic variability of vertical flows and the composition of settling sedimentary material, to obtain information on the quantitative characteristics of the processes that influence sound-scattering layers in the water layer above the continental slope behind the shelf edge in the northeastern part of the Black Sea. The results were obtained due to improvement of the equipment and the procedures for performing sea experiments on studying physicogeological, biological, and hydrophysical processes in the upper illuminated layer of phytoplankton development.

  6. Radiolarian artificial neural network based paleo sea surface water temperature and salinity changes during the last glacial cycle in the Timor Sea, Indian Ocean

    NASA Astrophysics Data System (ADS)

    Gupta, S. M.; Malmgren, B. A.

    2015-12-01

    The western Pacific water enters into the Timor Sea (tropical Indian Ocean) by the thermohaline conveyor belt, and this region is under the influence of the SW monsoon. The higher precipitation during the monsoon rains lower the surface salinity in the north-eastern Indian Ocean towards the Bay of Bengal; whereas, the Arabian Sea remains highly saline due to higher evaporation in the region surrounding Arabian deserts. The salinity contrast in the northern Indian Ocean is very unique, and the radiolarian micro-zooplanktons living in the surface water serve a very good proxy for the monsoonal changes in the surface sea-water temperature (SST) and salinity in the geological past. We studied radiolarian faunal variation in the core MD01-2378, located at ~13oS and ~121oE (1783 m water depth), at the inlet of the thermohaline circulation into the Timor Sea. We applied the modern radiolarian based artificial neural networks (ANNs) (Gupta and Malmgren, 2009) to derive the SST and salinity during August-October for the last 140 ka (the full last glacial cycle). Based on the mean estimates of the 10 ANNs, the root mean square error in prediction (RMSEP) for SST is ~1.4oC with correlation between observed and estimated values r=0.98 (Gupta and Malmgren, 2009). Similarly, the RMSEP is 0.3 psu (r=0.94) for the salinity estimates. We derived paleo-SSTs and salinity values using modern radiolarian ANNs and the fossil radiolarian data generated from the core for the last 140-ka (Fig.1). The age model of the core is based on δ18O benthic oxygen isotope stratigraphy and 21 AMS 14C ages up to ~30-ka (Holbourn et al., 2005). Paleo SST-summer varied between 22-28.5oC, and it is in very good agreement with the δ18O benthic record of Holbourn et al. (2005) defining the Last Glacial Maximum (~24 ka) and the Eemian (~125 ka) stages. The salinity fluctuated between 34-35 psu, and compared well with oxygen isotope record representing the LGM and Eemian periods. We gratefully acknowledge

  7. Acoustic and visual surveys for bowhead whales in the western Beaufort and far northeastern Chukchi seas

    NASA Astrophysics Data System (ADS)

    Moore, Sue E.; Stafford, Kathleen M.; Munger, Lisa M.

    2010-01-01

    Two types of passive-acoustic survey were conducted to investigate the seasonal occurrence of bowhead whales ( Balaena mysticetus) in the western Beaufort and far northeastern Chukchi seas: (1) an over-winter (2003-04) survey using autonomous recorders deployed northeast of Barrow, Alaska, and (2) a summertime dipping-hydrophone survey along the 2005 NOAA Ocean Exploration (OE) cruise track northwest of Barrow. The longest continuous sampling period from the over-winter survey was 3 October 2003 to 12 May 2004. During that period, bowhead whale calls were recorded from 3 to 23 October, intermittently on 6-7 and 22-23 November, then not again until 25 March 2004. Bowhead calls were recorded almost every hour from 19 April to 12 May 2004, with a call rate peak on 30 April ( ca. 9400 calls) and a few instances of patterned calling (or, "song") detected in early May. Bowhead whale calls were never detected during the NOAA OE cruise, but calls of beluga whales ( Delphinapterus leucas) were recorded at 3 of 16 acoustic stations. Opportunistic visual surveys for marine mammals were also conducted during the NOAA OE cruise from the ship (65 h) and helicopter (7.8 h), resulting in single sightings of bowhead whales (3-5 whales), beluga (16-20 whales), walrus (1), polar bear (2=sow/cub), and 17 sightings of 87 ringed seals from the ship and 15 sightings of 67 ringed seals from the helicopter.

  8. Millennial-scale sea ice variability in the southern Indian Ocean during the last glacial

    NASA Astrophysics Data System (ADS)

    Ikehara, M.; Katsuki, K.; Yamane, M.; Yokoyama, Y.

    2014-12-01

    The Southern Ocean has played an important role in the evolution of the global climate system. Sea ice coverage on sea surface strongly affects the climate of the Southern Hemisphere through its impacts on the energy and gas budget, on the atmospheric circulation, on the hydrological cycle, and on the biological productivity. In this study, we have conducted fundamental analyses of ice-rafted debris (IRD) and diatom assemblage to reveal a rapid change of sea ice distribution in the glacial southern Indian Ocean. Piston cores COR-1bPC and DCR-1PC were collected from the Conrad Rise and Del Caño Rise, Indian sector of the Southern Ocean. Age models of the cores were established by radiocarbon dating and oxygen isotope stratigraphy of planktic and benthic foraminifers. Records of IRD concentration suggest millennial-scale pulses of IRD delivery during the last glacial period. The depositions of rock-fragment IRD excluding volcanic glass and pumice were associated with increasing of sea-ice diatoms, suggesting that the millennial-scale events of cooling and sea-ice expansion were occurred in the southern Indian Ocean during the last glacial period. Provenance study of IRD grains suggest that the source of IRD in the southern Indian Ocean was mainly volcanic arc in the South Atlantic, based on chemical compositions of rock-fragment IRD grains. Thus prominent IRD layers in the glacial Southern Ocean suggest episodes of sea ice expansion and cooling in the Indian sectors of the Southern Ocean.

  9. Influence of small river derived sediment on the Northeastern South China Sea sedimentation processes in the last 40 K years

    NASA Astrophysics Data System (ADS)

    Cheng, Wan-Yen; Lin, Saulwood; Lou, Jiann-Yuh; Wei, Kuo-Yen; Liu, CharShine; Chen, Shing-Li; Wang, Yun-Shuen

    2015-04-01

    Small rivers derived particles are major source of sediment to the ocean in the present time. Small rivers in Taiwan are subjected to fast tectonic activity, high precipitation rate and erosion rate. The combined annual river particle load from small rivers on the Island of Taiwan is higher than that of the Mississippi River. A large fraction of those rivers particle may finding its way into the surrounding seas and ocean, e.g. South China Sea, East China Sea, and the Philippine Sea. Furthermore, due to the nature of particle transportation off rivers from Taiwan were connected by a number of canyon systems close by the river mouth, majority of those river particles were facilitated in delivering and deposited later further into the South China Sea deep basin. The objectives of this study are to understand spatial variations in sedimentation rates and to resolve the temporal differences in sedimentation in the Northeastern South China Sea region, and to evaluate influence of small river particles to the marginal sea. A set of cores was collected in overlying water depth within 1600 - 3300 m for mutilsensor core logging of magnetic susceptibility, density, and porosity. Foraminifera (G. sacculifer, G. conglobatus, O. universa) were picked and AMS C14 analyses for age determination. Grain size, organic carbon, carbonate and biogenic silica content were measured. The results show that large sedimentation rates difference existed in the study area. Earlier studies on sedimentation rate in the region west of our study area were in range of about 10 cm/kyr while our rates are about 20-40 cm/kyr and much higher near Taiwan. Bulk sedimentation rate were higher during the transition period between LGM and Holocene and lower during Holocene. Our results demonstrated that large quantity of particles from small rivers in Taiwan are and were major source of particle and are the dominating factor in controlling sediment deposition in the northeastern South China Sea.

  10. Inhibition of mixed-layer deepening during winter in the northeastern Arabian Sea by the West India Coastal Current

    NASA Astrophysics Data System (ADS)

    Shankar, D.; Remya, R.; Vinayachandran, P. N.; Chatterjee, Abhisek; Behera, Ambica

    2015-10-01

    Though the deep mixed layers (MLs) that form in the northeastern Arabian Sea (NEAS) during the winter monsoon (November-February) have been attributed to convective mixing driven by dry, cool northeasterly winds from the Indian subcontinent, data show that the deepest MLs occur in the northern NEAS and the maxima of latent-heat and net heat fluxes in the southern NEAS. We use an oceanic general circulation model to show that the deep MLs in the NEAS extend up to ~20°N till the end of December, but are restricted poleward of ~22°N (~23°N) in January (February). This progressive restriction of the deep mixed layers within the NEAS is due to poleward advection of water of lower salinity by the West India Coastal Current (WICC). The deep MLs are sustained till February in the northern NEAS because convective mixing deepens the ML before the waters of lower salinity reach this region and the wind stirring and convective overturning generate sufficient turbulent energy for the ML to maintain the depth attained in January. Though the atmospheric fluxes tend to cool the ML in the southern NEAS, this cooling is countered by the warming due to horizontal advection. Likewise, the cooling due to entrainment, which continues in the southern NEAS even as the ML shallows during January-February, is almost cancelled by the warming caused by a downwelling vertical velocity field. Therefore, the SST changes very little during December-February even as the ML shallows dramatically in the southern NEAS. These deep MLs of the NEAS also preclude a strong intraseasonal response to the intraseasonal variability in the fluxes. This role of horizontal advection implies that the ML depth in the NEAS is determined by an interplay of physical processes that are forced differently. The convective mixing depends on processes that are local to the region, but the advection is due to the WICC, whose seasonal cycle is primarily forced by remote winds. By inhibiting the formation of deep MLs in

  11. Inhibition of mixed-layer deepening during winter in the northeastern Arabian Sea by the West India Coastal Current

    NASA Astrophysics Data System (ADS)

    Shankar, D.; Remya, R.; Vinayachandran, P. N.; Chatterjee, Abhisek; Behera, Ambica

    2016-08-01

    Though the deep mixed layers (MLs) that form in the northeastern Arabian Sea (NEAS) during the winter monsoon (November-February) have been attributed to convective mixing driven by dry, cool northeasterly winds from the Indian subcontinent, data show that the deepest MLs occur in the northern NEAS and the maxima of latent-heat and net heat fluxes in the southern NEAS. We use an oceanic general circulation model to show that the deep MLs in the NEAS extend up to ~20°N till the end of December, but are restricted poleward of ~22°N (~23°N) in January (February). This progressive restriction of the deep mixed layers within the NEAS is due to poleward advection of water of lower salinity by the West India Coastal Current (WICC). The deep MLs are sustained till February in the northern NEAS because convective mixing deepens the ML before the waters of lower salinity reach this region and the wind stirring and convective overturning generate sufficient turbulent energy for the ML to maintain the depth attained in January. Though the atmospheric fluxes tend to cool the ML in the southern NEAS, this cooling is countered by the warming due to horizontal advection. Likewise, the cooling due to entrainment, which continues in the southern NEAS even as the ML shallows during January-February, is almost cancelled by the warming caused by a downwelling vertical velocity field. Therefore, the SST changes very little during December-February even as the ML shallows dramatically in the southern NEAS. These deep MLs of the NEAS also preclude a strong intraseasonal response to the intraseasonal variability in the fluxes. This role of horizontal advection implies that the ML depth in the NEAS is determined by an interplay of physical processes that are forced differently. The convective mixing depends on processes that are local to the region, but the advection is due to the WICC, whose seasonal cycle is primarily forced by remote winds. By inhibiting the formation of deep MLs in

  12. Adaptation to the impact of sea level rise in the Northeastern Nile Delta, Egypt

    NASA Astrophysics Data System (ADS)

    Mabrouk, Badr; Farhat Abd-Elhamid, Hany; Badr, Marmar; Ludwig, Ralf

    2013-04-01

    Northeastern Delta is one of the most promising developmental areas in Egypt. This area is characterized by a prominent watershed having abundant water resources (especially groundwater). Currently, this area undergoes a rapid environmental degradation, such as land subsidence, water and soil salinaization. It accommodates about 60% of the total arable lands of the Delta, and inhabited by about 45 % of its total population. In addition, the northern part of this area comprises about 25% of the total Mediterranean wetlands. In this area a number of desalination plants were installed to desalinate brackish water and inject the brine to the aquifer using deep wells. This work aims to evaluate the environmental impact of injecting brine water on groundwater quality. Also, the impact of climate change and sea level rise are considered. The work is a combination of field work and simulation processes of groundwater flow and seawater intrusion using numerical models. The field work was used to collect and analyze data, information pertaining to the groundwater resources, interpretation of aerial photos and satellite images and preparation of ground water potential maps has. This was followed by detailed test boring wells as chemical analysis of seawater intrusion detection and pollution flow mapping were done. Numerical models (MODFLOW and MT3D) were used to evaluate both current and future situation of the groundwater flow and seawater intrusion in the Nile Delta aquifer in the studied area. The aquifer in the studied area is divided into five barrier beds according to its hydrological characteristics. The increase in extraction rates of brackish water and increasing the salinity of groundwater were experienced in details. Different scenarios to mitigate the severe salinity effect of injected brine water of high salinity rejected from desalination process. The brine water is assumed to be injected into deep wells to different depths and observation of changes in salinity

  13. A qualitative study on sea surface temperature over the tropical Indian Ocean and performance of Indian summer monsoon

    NASA Astrophysics Data System (ADS)

    Singh, Umesh Kumar; Singh, Gyan Prakash

    2012-08-01

    A careful analysis of the sea surface temperature (SST) over the tropical Indian Ocean using the available SST data sets (namely, Hadley Center Ice SST, tropical rainfall measuring mission microwave imager SST, and optimum interpolation SST) at different time scales has been presented in the present study. By simple visual inspection of the SST plots, it has been shown that the qualitative prediction of Indian summer monsoon condition (weak/normal) and northern limit of monsoon (NLM) can be possible a month in advance using SST. The present qualitative study may be useful for common man to know the behavior of summer monsoon well a month in advance. Therefore, the qualitative study may enable the common man to show the application of satellite data to bring out the information regarding the onset of summer monsoon and related performance of Indian summer monsoon well in advance.

  14. Sea breeze Initiated Rainfall over the east Coast of India during the Indian Southwest Monsoon

    SciTech Connect

    Simpson, M; Warrior, H; Raman, S; Aswathanarayana, P A; Mohanty, U C; Suresh, R

    2006-09-05

    Sea breeze initiated convection and precipitation is investigated along the east coast of India during the Indian southwest monsoon season. The sea breeze circulations are observed approximately 70 to 80% of the days during the summer months (June to August) along the Chennai coast. Observations of average sea breeze wind speeds are stronger at a rural location as compared to the wind speeds observed inside the urban region of Chennai. The sea breeze circulation is shown to be the dominant mechanism for initiating rainfall during the Indian southwest monsoon season. Roughly 80% of the total rainfall observed during the southwest monsoon over Chennai is directly related to the convection initiated by sea breeze circulation.

  15. Black carbon in deep-sea sediments from the northeastern equatorial Pacific Ocean

    NASA Astrophysics Data System (ADS)

    Kim, D.; Lee, Y.; Hyeong, K.; Yoo, C.

    2011-12-01

    Deep-sea sediment core is a good archive for understanding the land-ocean interactions via atmosphere, due to it is little influenced by fluvial and continental shelf processes. This study dealt with black carbon(BC) in a 328 cm-long piston core collected from the northeastern equatorial Pacific Ocean (16°12'N, 125°59'W), covering the last 15 Ma (Hyeong at al., 2004). BC is a common name of carbon continuum formed by incomplete combustion of fossil fuels and plant materials. Though it may react with ozone and produce water-soluble organic carbon, BC has commonly refractory nature. Thus BC in preindustrial sediment can be a tracer of forest-fire events. BC is purely terrestrial in origin, and is transported to marine environments by atmospheric and fluvial processes. Therefore, distribution of BC in deep-sea sediments could be used to understand atmospheric circulation. Chemical oxidation was used to determine BC in this study following Lim and Cachier (1996). Concentration of BC varies from 0.010% to 0.233% of total sediments. Mass accumulation rate (MAR) of BC ranged between 0.077 mg/cm^2/1000 yrs and 47.49 mg/cm^21000 yrs. It is noted that MAR in sediments younger than 8 Ma (av. 9.0 mg/cm^2/1000 yrs) is higher than that in sediments older than 8 Ma (av. 3.2 mg/cm^2/1000 yrs). Stable carbon isotope value of BC increases with time from the low δ13C value near 13 Ma until it reaches the highest value near 4 Ma. Change of MAR seems to be related to the meridional migration of Intertropical Convergence Zone (ITCZ) at around 8 Ma in the study area (cf., Hyeong at al., 2004). Accordingly, higher BC content in sediment younger than 8 Ma seems to be accounted for by its derivation from the Northern Hemisphere compared to that from the Southern Hemisphere in older sediment. Increase of carbon isotope value with time seems to be related to expansion of C4 grassland. C4 grassland expansion might have been caused by change of atmosphreic cycle, which moved dry subtropical

  16. Results of many-year subsatellite measurements of current fine structure in northeastern Black Sea

    NASA Astrophysics Data System (ADS)

    Lavrova, Olga; Krayushkin, Evgeny; Kalashnikova, Nina

    Results of subsatellite measurements of coastal currents in the shelf zone of northeastern Black Sea are presented. The measurements have been performed every year since 2006 in June and September-October months near the Gelendzhik Bay. The main instruments used are Acoustic Doppler Current Profilers (ADCP) and CTD probes. Ground and ship measurements were conducted simultaneously with satellite imaging in microwave (ASAR Envisat, ERS-2, RADARSAT-2, TerraSAR-X), visible and infrared (OLI Landsat-8, ETM+ Landsat-7, TM Landsat-5, MODIS Terra/Aqua, AVHRR NOAA) ranges. The investigations performed revealed spatial, depth and temporal variability of current direction and velocity in the shelf zone. Multiple instances of counter-currents opposing to the Ring Current were registered. In our view, they are associated with a passage of small-scale anticyclonic eddies across the region of interest. The 3D structure of the eddies in the upper quasi-uniform layer was analyzed based on ADCP data. The use of high resolution (3 m) SAR data in combination with ADCP measurements at the resolution of 0.5 m allowed us to detect a number of internal wave trains. Form ADCP and thermistors records, their amplitudes were estimated to reach 5-8 m. Joint analysis of satellite SAR and subsatellite data gave an assessment of their typical wavelength at 90-100 m. Generation mechanisms of these internal waves are suggested. Another phenomenon of interest observed in the region of the measurements is surface manifestations of ring waves near localized natural and anthropogenic generation sources. Such ring waves are most frequently found in the anchor area for ships, whose oscillations can be the source of their generation. The work was in part supported by the Russian Foundation for Basic Research (projects #14-05-00520-а, and 13-07-12017-ofi_m). SAR data from RADARSAT-2 and TerraSAR-X were obtained under SOAR RADARSAT-2/TerraSAR-X Project #5074.

  17. Signals of the South China Sea summer rainfall variability in the Indian Ocean

    NASA Astrophysics Data System (ADS)

    He, Zhuoqi; Wu, Renguang; Wang, Weiqiang

    2016-05-01

    The present study investigates signals of the South China Sea (SCS) summer rainfall variability in the Indian Ocean. It is found that the SCS summer rainfall has a negative relationship with December-January-February (DJF) western-equatorial Indian Ocean (WIO) sea surface temperature (SST), a positive relationship with an asymmetric mode of precipitation anomalies in the tropical Indian Ocean during March-April-May (MAM), and a positive relationship with June-July-August (JJA) South Indian Ocean (SIO) SST. The WIO SST anomalies induce same-sign southeast Indian Ocean SST anomalies through an anomalous zonal vertical circulation. The southeast Indian Ocean SST anomalies last from late winter to early summer and induce opposite-sign SCS summer rainfall anomalies via an anomalous meridional vertical circulation. The asymmetric mode influences the SCS summer rainfall variation via the North Indian Ocean (NIO) SST anomalies with significant cloud-radiation and wind-evaporation effect. Positive (negative) SIO SST anomalies drive an anomalous direct circulation between the SIO and the NIO, and an anomalous indirect circulation between the NIO and the SCS which facilitates the occurrence of cyclonic (anti-cyclonic) wind anomalies over the SCS-western North Pacific and results in positive (negative) SCS summer rainfall anomalies. Partial correlation analysis indicates that the influence of DJF WIO SST anomalies and JJA SIO SST anomalies on the SCS summer rainfall is partly ENSO-independent, while the MAM asymmetric mode is mostly related to the preceding DJF eastern Pacific SST anomalies.

  18. Galatheid and chirostylid crustaceans (Decapoda: Anomura) from a cold seep environment in the northeastern South China Sea.

    PubMed

    Dong, Dong; Li, Xinzheng

    2015-01-01

    Six species of squat lobsters from a cold seep field in the northeastern South China Sea are studied. Two new species, Uroptychus jiaolongae n. sp. and U. spinulosus n. sp., are described, and their distinctions from the related species are detailed. Two species, Munidopsis tuberosa Osawa, Lin & Chan, 2008 and M. verrilli Benedict, 1902, are herein reported for the first time from a cold seep/hydrothermal vent environment. The number of squat lobsters species associated with those chemosynthetic environments now stands at forty-one. PMID:26701467

  19. Phytoplankton dynamics driven by vertical nutrient fluxes during the spring inter-monsoon period in the northeastern South China Sea

    NASA Astrophysics Data System (ADS)

    Li, Q. P.; Dong, Y.; Wang, Y.

    2015-05-01

    A field survey from the coastal upwelling zones to the offshore pelagic zones of the northeastern South China Sea (SCS) was conducted during the inter-monsoon period of May 2014 when the region was characterized by prevailing low-nutrient conditions. Comprehensive field measurements were made for not only hydrographic and biogeochemical properties but also phytoplankton growth and microzooplankton grazing rates. We also performed estimations of the vertical turbulent diffusivity and diffusive nutrient fluxes using a Thorpe-scale method and the upwelling nutrient fluxes by Ekman pumping using satellite-derived wind stress curl. Our results suggest that phytoplankton patchiness in the northeastern SCS during the study period could be largely controlled by vertical nutrient fluxes with combined contributions from both turbulent diffusion and curl-driven upwelling. Our results also reveal the generally increasing role of turbulent diffusion but decreasing role of curl-driven upwelling on vertical transport of nutrients from the coastal upwelling zones to the offshore pelagic zones in the northeastern SCS. Elevated nutrient fluxes observed near Dongsha Island were found to support high new production leading to net growth of a diatom-rich phytoplankton community, whereas the low nutrient fluxes near southwest Taiwan resulted in a negative net community growth leading to a decline of a picoplankton-dominant phytoplankton bloom.

  20. Late Quaternary sea-level highstands in the central and eastern Indian Ocean: A review

    NASA Astrophysics Data System (ADS)

    Woodroffe, Colin D.

    2005-11-01

    The relative sea-level history of several atolls in the central and eastern Indian Ocean, including the Cocos (Keeling) Islands, Chagos Archipelago, and the Maldives-Laccadive Archipelagoes, has been debated for over a century but takes on a particular significance in the face of anticipated climate change. For each of these central and eastern Indian Ocean atolls Pleistocene limestone is encountered at depths of 6-20 m below sea level. On the Cocos (Keeling) Islands this has been dated to Last Interglacial age. Conglomerate platform underlies the reef islands on Cocos within which a sequence of fossil microatolls of massive and branching Porites records a gradual fall of sea level relative to the atoll. In the Maldives, the significance of outcrops of 'reef rock' has been vigorously debated without resolving sea-level history. Although in situ Heliopora occurs on the reef flat of Addu Atoll, dated at around 2700 radiocarbon yrs BP, other evidence for higher sea level remains poorly constrained. Conglomerates of a similar age have been described from the Chagos Archipelago, but it has not been unequivocally demonstrated that they formed under conditions of relatively higher sea level. In contrast to reefs further west in the Indian Ocean, each of these atolls has living microatolls of massive Porites that have been constrained in their upward growth by sea level. Interpretation of the upper surface of two such specimens from the Cocos (Keeling) Islands indicates broad fluctuations in the sea surface over the past century; similar microatolls are described from the Maldives implying little change in sea level over recent years. Regardless of minor past fluctuations, most reef islands in the Maldives are particularly low-lying and appear vulnerable to inundation, and extracting a more detailed sea-level history remains an important challenge.

  1. 250 years of SW Indian Monsoon Variability from Red Sea Corals

    NASA Astrophysics Data System (ADS)

    Bryan, S.; Hughen, K. A.; Karnauskas, K. B.; Farrar, J. T.

    2015-12-01

    During the northern hemisphere summer, strong dust storms develop in the Tokar Delta region of Sudan. These massive dust storms are funneled through a gap in the coastal mountains and blow out across the Red Sea. The generation and transport of these dust storms is driven by the large-scale atmospheric pressure gradient across the Red Sea, which is a component of the Southwest Indian Monsoon. Dust deposited on the Red Sea is recorded in skeletal geochemistry of corals that live on the Saudi Arabian coast, and provides an opportunity to reconstruct variability in the monsoon system prior to instrumental records. We have generated annually-resolved records of coral Ba/Ca, which display strong correlations to the zonal pressure gradient across the Red Sea during the instrumental period. Our coral-based monsoon records show an increasing trend in the strength of SW Indian Monsoon circulation since the Little Ice Age, in agreement with lower-resolution Arabian Sea upwelling based records. Our records also show strong decadal-scale variability, which was strongest during the late 19th century and has declined during the past century. In this presentation, we will discuss the decadal-scale variability in the SW Indian Monsoon circulation over the past 250 years as revealed by Red Sea Corals and the implications of the relationships and trends observed in this study for projections of future monsoon variability.

  2. Underwater Acoustic Localization and Tracking of Pacific Walruses in the Northeastern Chukchi Sea

    NASA Astrophysics Data System (ADS)

    Rideout, Brendan Pearce

    This thesis develops and demonstrates an approach for estimating the three-dimensional (3D) location of a vocalizing underwater marine mammal using acoustic arrival time measurements at three spatially separated receivers while providing rigorous location uncertainties. To properly account for uncertainty in the measurements of receiver parameters (e.g., 3D receiver locations and synchronization times) and environmental parameters (water depth and sound speed correction), these quantities are treated as unknowns constrained with prior estimates and prior uncertainties. While previous localization algorithms have solved for an unknown scaling factor on the prior uncertainties as part of the inversion, in this work unknown scaling factors on both the prior and arrival time uncertainties are estimated. Maximum a posteriori estimates for sound source locations and times, receiver parameters, and environmental parameters are calculated simultaneously. Posterior uncertainties for all unknowns are calculated and incorporate both arrival time and prior uncertainties. Simulation results demonstrated that, for the case considered here, linearization errors are generally small and that the lack of an accurate sound speed profile does not necessarily cause large uncertainties or biases in the estimated positions. The primary motivation for this work was to develop an algorithm for locating underwater Pacific walruses in the coastal waters around Alaska. In 2009, an array of approximately 40 underwater acoustic receivers was deployed in the northeastern Chukchi Sea (northwest of Alaska) from August to October to record the vocalizations of marine mammals including Pacific walruses and bowhead whales. Three of these receivers were placed in a triangular arrangement approximately 400 m apart near the Hanna Shoal (northwest of Wainwright, Alaska). A sequence of walrus knock vocalizations from this data set was processed using the localization algorithm developed in this thesis

  3. Sea-floor character and geology off the entrance to the Connecticut River, northeastern Long Island Sound

    USGS Publications Warehouse

    Poppe, Lawrence J.; McMullen, Katherine Y.; Ackerman, Seth D.; Guberski, Megan R.; Wood, Douglas A.

    2013-01-01

    Datasets of gridded multibeam bathymetry and sidescan-sonar backscatter, together covering approximately 29.1 square kilometers, were used to interpret character and geology of the sea floor off the entrance to the Connecticut River in northeastern Long Island Sound. Although originally collected for charting purposes during National Oceanic and Atmospheric Administration hydrographic survey H12013, these acoustic data, sidescan-sonar imagery, and the sea-floor sampling and photography stations subsequently occupied to verify the acoustic data (1) show the composition and terrain of the seabed, (2) provide information on sediment transport and benthic habitat, and (3) are part of an expanding series of studies that provide a fundamental framework for research and resource management (for example, cables, pipelines, and dredging) activities in this major east coast estuary.

  4. The morphology of saccular otoliths as a tool to identify different mugilid species from the Northeastern Atlantic and Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Callicó Fortunato, Roberta; Benedito Durà, Vicent; Volpedo, Alejandra

    2014-06-01

    In the Northeastern Atlantic and Mediterranean Sea there are 8 species of the Mugilidae family: Mugil cephalus, Liza aurata, Liza ramada, Oedalechilus labeo, Chelon labrosus, Liza saliens, Liza carinata and Liza haematocheila. The identification of mugilids is very important for local fisheries management and regulations, but it is difficult using gross morphological characters. This work aims to contribute to the identification of mullets present in the Northeastern Atlantic Ocean and Mediterranean Sea using saccular otolith features of each species. Specimens of C. labrosus, L. aurata, L. ramada, L. saliens and M. cephalus were obtained from Delta del Ebro (40°38'N-0°44'E) in artisanal catches. For L. carinata and O. labeo photographs extracted from AFORO online database were used. L. haematocheila was not studied for lack of otolith samples. A general pattern of the saccular otoliths for this family was identified: the shape of the otoliths are rectangular to oblong with irregular margins; they present a heterosulcoid, ostial sulcus acusticus, with an open funnel-like ostium to the anterior margin and a closed, tubular cauda, ending towards the posterior ventral corner, always larger than the ostium. In the present study, the mugilid species could be recognized using their saccular otolith morphology. Here we give the first key to identify Northeastern Atlantic and Mediterranean mullets. The distinctive features between the species were the position and centrality of the sulcus, the curvature of the cauda, the presence of areal depositions and plateaus, and the type of anterior and posterior regions. These features could be used not only to reinforce the identification keys through morphological and meristic characters of the species, but also to identify the species consumed by piscivores, being the otoliths the only identifiable remains of the individuals.

  5. Benthic ecology of the northeastern Chukchi Sea. Part I. Environmental characteristics and macrofaunal community structure, 2008-2010

    NASA Astrophysics Data System (ADS)

    Blanchard, Arny L.; Parris, Carrie L.; Knowlton, Ann L.; Wade, Nicole R.

    2013-09-01

    Spatial variations of processes driving macrofaunal distributions can arise from interactions among topographic features and oceanographic patterns, and are not understood at small scales in the northeastern Chukchi Sea. Benthic macrofauna and environmental characteristics were measured to determine factors driving macrofaunal distributions as part of a multidisciplinary environmental program in the northeastern Chukchi Sea from 2008 to 2010. Macrofauna were sampled in three study areas, named Klondike, Burger, and Statoil, with a van Veen grab at up to 82 stations each year, as well as an area where marine mammals were seen feeding. The macrofaunal assemblages in all study areas were similar in species-composition with deposit-feeding polychaetes (53% of density and of 26% biomass) and bivalves (15% of density and 52% of biomass) collectively the most prominent groups. Maldane sarsi dominated the polychaetes in terms of both density and biomass, while bivalves were numerically dominated by Ennucula tenuis, but their biomass was dominated by larger species such as Macoma calcarea and Astarte borealis. Exceptions occurred in the marine mammal feeding area that was dominated by amphipods (71% of density and 30% biomass). Average densities were higher in Burger than in Klondike or Statoil, while biomass values were similar between Burger and Statoil, and higher in these two study areas than in Klondike. Overall, the distributions, biomass and density of benthic macrofauna reflect the high volume of production reaching the seafloor in the shallow waters of the Chukchi Sea. Variations in community structure among study areas were correlated with water depth and bottom-water temperature. Short-term temporal differences in community structure covaried with interannual oceanographic variations that may have altered food availability, macrofaunal survival, or larval recruitment. Topographic control over circulation appears to be a primary driver in structuring benthic

  6. Seasonal variations of sea-surface salinity and temperature in the tropical Indian Ocean

    NASA Astrophysics Data System (ADS)

    Donguy, Jean-Rene; Meyers, Gary

    1996-02-01

    Measurements of sea-surface temperature and sea-surface salinity obtained from ships-of-opportunity are used to map the fields in the tropical Indian Ocean. The seasonal variation is described in detail along the six shipping tracks that have the best data coverage: Gulf of Aden to La Reunion island, Persian Gulf to Cape Town, Gulf of Aden to east Africa, Gulf of Aden to Indonesia, Sri Lanka to Torres Strait through Malacca Strait, and along the west coast of Australia. Seasonal variation with large amplitude is found in an extensive area in the western Indian Ocean. In the eastern Indian Ocean, seasonal variation is small, except where it is linked to local features such as coastal upwelling, local wind or rainfall-runoff. Water masses, defined from the surface T- S diagram, are related to winds and currents or are formed locally. The movement of these water masses is linked to currents driven by the monsoon circulation.

  7. A recent increase in the rate of Indian Ocean sea level change

    NASA Astrophysics Data System (ADS)

    Thompson, P. R.; Merrifield, M. A.

    2014-12-01

    Decadal rates of sea surface height (SSH) change measured by satellites (1993-present) north of 20°S in the Indian Ocean increase substantially after the turn of the century. In contrast, the increase in the sea surface temperature of the region is approximately linear. This increase in Indian Ocean rates of SSH change appears to be thermosteric in origin, but it is not accounted for variability in Pacific climate indices. We find the GECCO2 simulation (1948-2011) reproduces the SSH variability in this region to good approximation, and we use the model fields to diagnose the origin of the increase in the rate of Indian Ocean SSH change and to place the recent variability in historical context.

  8. Structure and evolution of the Afanasy Nikitin seamount, buried hills and 85°E Ridge in the northeastern Indian Ocean

    NASA Astrophysics Data System (ADS)

    Krishna, K. S.

    2003-04-01

    Geophysical data of the Afanasy Nikitin seamount (ANS), partly buried hills and 85°E Ridge in the northeastern Indian Ocean were studied together with published seismic refraction results to understand genesis and evolution of the structures. The ANS joins the 85°E Ridge through isolated buried hills and intervening subsurface structures and together they form a linear ridge system. The gravity signature of the ridge system changes from negative to positive towards south of 5°N, which seems to coincide with termination/thinning of pre-collision continental sediments in the Bay of Bengal. Thick pile of Bengal Fan sediments had great impact on underneath pre-collision sediments as well as on basement rocks; the process resulted in attaining higher velocities, up to 6.6 and 7.1 km/s, respectively. Gravity model studies suggest that structures of the ridge system are compensated in different modes. The ANS is underlain by an 8 km thick, deep crustal body of magmatic rocks, while beneath other structures oceanic crust is down-flexed up to 2.5 km. The presence of metasediments, more dense than volcanic rocks, and flexure of the lithosphere would explain the negative gravity anomaly over the 85°E Ridge, whereas lack of metasediments and magmatic rocks at depth would explain the compensated positive anomaly over the ANS. The width of the 85°E Ridge, the wavelength (˜190 km) and amplitude (˜2.5 km) of the flexed oceanic crust and the intersection of the ridge with the Mesozoic fracture zones suggest that the ridge was formed in intraplate position when the lithosphere underneath was approximately 35 Myr old. Initial emplacement of the ANS was coeval with the formation of oceanic lithosphere at 80-73 Ma. The hotspot forming the 85°E Ridge had reactivated the ANS during the Paleocene and brought it to the sea surface. Then it underwent erosion and subsidence processes. The deformation activity had converged the north and south parts of the ANS at late Miocene and

  9. New deep-sea Paratanaoidea (Crustacea: Peracarida: Tanaidacea) from the northeastern Gulf of Mexico.

    PubMed

    Drumm, David T; Bird, Graham J

    2016-01-01

    One new genus is erected and four new species of paratanaoidean tanaidaceans are described from deep waters in the northeastern Gulf of Mexico: one in each of the genera Collettea, Tanaella, and Pseudomacrinella, and one as a new genus in the family Anarthruridae. Keys to species in the genera Collettea, Tanaella, and the genera of the Anarthruridae are provided. PMID:27615848

  10. Origins of wind-driven intraseasonal sea level variations in the North Indian Ocean coastal waveguide

    NASA Astrophysics Data System (ADS)

    Suresh, I.; Vialard, J.; Lengaigne, M.; Han, W.; McCreary, J.; Durand, F.; Muraleedharan, P. M.

    2013-11-01

    this paper, we show that a linear, continuously stratified ocean model reproduces observed wind-driven intraseasonal sea level variability in the coastal waveguide of the Northern Indian Ocean (NIO). Sensitivity experiments with intraseasonal wind forcing selectively applied in the equatorial region, Bay of Bengal, and Arabian Sea show that a large part of the basin-scale sea level variations are driven by zonal wind fluctuations along the equator. Within the NIO coastal waveguide, the contribution of remote equatorial forcing decreases from ~80-90% in the Andaman Sea to ~50% northeast of Sri Lanka and then increases to ~60-70% along the west coast of India. During the southwest monsoon, intraseasonal wind variations become stronger over the NIO, resulting in a larger contribution of local wind forcing to sea level variability along the west (up to 60%) and east (up to 40%) coasts of India.

  11. Benthic ecology of the northeastern Chukchi Sea. Part II. Spatial variation of megafaunal community structure, 2009-2010

    NASA Astrophysics Data System (ADS)

    Blanchard, Arny L.; Parris, Carrie L.; Knowlton, Ann L.; Wade, Nicole R.

    2013-09-01

    Sources for spatial variability of benthic megafaunal communities in the northeastern Chukchi Sea are poorly documented and may include altered water circulation patterns, as noted for macrofauna. Spatial variability of megafauna was investigated by sampling with a plumb-staff beam trawl in three petroleum leases, the Klondike, Burger, and Statoil study areas, as part of a multi-disciplinary research program in the northeastern Chukchi Sea ecosystem. Trawling occurred during two sampling periods from 2009 and one in 2010 with a total of 81 trawls from 38 stations. A total of 99 discrete taxonomic categories were identified in 2009 and 2010 which were expanded to 239 taxa in the laboratory. Biomass in the three study areas ranged from ∼15,500 to ∼96,000 g 1000 m-2 and numerical density ranged from ∼8500 to ∼134,000 individuals 1000 m-2. Although the megabenthic species-assemblages in all three study areas were similar in composition, average biomass values were higher in Burger (ranging from ∼54,000 to ∼96,000 g 1000 m-2) where altered water circulation occurs, than in Klondike (ranging from ∼15,500 to ∼31,000 g 1000 m-2) or Statoil (∼15,000 g 1000 m-2). The brittle star Ophiura sarsi was the numerically dominant megafauna (70% of total biomass) followed by the snow crab Chionoecetes opilio (7% total biomass), as noted in prior investigations in the region. Biomass and density of benthic megafauna in this region reflected the high quantities of seasonal production reaching the benthos in the shallow waters of the Chukchi Sea. Differences in benthic communities among study areas were associated with variations in bottom-water temperature and latitude, and to a lesser extent, water depth and percent mud. We believe these associations arise from effects of topography on northward-flowing water, that create regions of slower currents, and consequently, higher organic deposition.

  12. Buried paleo-sedimentary basins in the north-eastern Black Sea-Azov Sea area and tectonic implications (DOBRE-2)

    NASA Astrophysics Data System (ADS)

    Starostenko, Vitaly; Stephenson, Randell; Janik, Tomasz; Tolkunov, Anatoly

    2014-05-01

    A number of independent but inter-related projects carried out under the auspices of various national and international programmes in Ukraine including DARIUS were aimed at imaging the upper lithosphere, crustal and sedimentary basin architecture in the north-eastern Black Sea, southern Crimea and Kerch peninsulas and the Azov Sea. This region marks the transition from relatively undisturbed Precambrian European cratonic crust and lithosphere north of the Azov Sea to areas of significant Phanerozoic tectonics and basin development, in both extensional as well as compressional environments, to the south, including the eastern Black Sea rift, which is the main sedimentary basin of the study area. The wide-angle reflection and refraction (WARR) profile DOBRE-2, a Ukrainian national project with international participation (see below), overlapping some 115 km of the southern end of the DOBREfraction'99 profile (that crosses the intracratonic Donbas Foldbelt) in the north and running to the eastern Black Sea basin in the south, utilised on- and offshore recording and energy sources. It maps crustal velocity structure across the craton margin and documents, among other things, that the Moho deepens from 40 km to ~47 km to the southwest below the Azov Sea and Crimean-Caucasus deformed zone. A regional CDP seismic profile coincident with DOBRE-2, crossing the Azov Sea, Kerch Peninsula and the north-eastern Black Sea southwest to the Ukraine-Turkey border, acquired by Ukrgeofisika (the Ukrainian national geophysical company) reveals in its inferred structural relationships the ages of Cretaceous and younger extensional and subsequent basin inversion tectonic events as well as the 2D geometry of basement displacement associated with post mid-Eocene inversion. A direct comparison of the results of the WARR velocity model and the near-vertical reflection structural image has been made by converting the former into the time domain. The results dramatically demonstrate that

  13. Connection of sea level height between Western Pacific and South Indian Ocean in recent decades

    NASA Astrophysics Data System (ADS)

    DU, Y.; Wang, T.; Zhuang, W.; Wang, J.

    2014-12-01

    Based on merged altimetry data and in site observations from tide gauges, we analyzed the fast increasing trend of sea surface height (SSH) in the recent two decades in the tropical Pacific and Indian Ocean. The results of analysis indicated a dynamic connection of SSH between the tropical western Pacific and the southeastern Indian Ocean. The low-frequency variations of SSH propagate westward in the tropical Pacific, enter the Indonesian Seas through the waveguide, and influence the southeastern India Ocean with the Kelvin-Rossby wave transformation. The thermal structure of upper ocean reveals the above adjustment mainly occur in the thermocline. However, the impacts from the Pacific are limited in the southeast Indian Ocean. In the central and west of the south Indian Ocean, local wind dominates the SSH changes in the last two decades. By lead-lag statistic analyses, we identified the cause of interdecadal from the interannual SSH variations. The interannual SSH variations is dominated by ENSO, forced by the anomalous wind along the equatorial Pacific. Whereas, the interdecadal SSH variations results from the off-equatorial wind stress curl, which is closely related to the Pacific Decadal Oscillation. The dynamic connections between the western Pacific and the south Indian Ocean were tested in the baroclinic Rossby wave solution and the numerical experiments based on the nonlinear reduced-gravity dynamics model.

  14. Supercritical turbidity-current bedforms in the northeastern continental slope, South China Sea

    NASA Astrophysics Data System (ADS)

    Zhong, Guangfa; Kuang, Zenggui; Cartigny, Matthieu J. B.; Guo, Yiqun; Wang, Liaoliang

    2015-04-01

    Large-scale Supercritical flow bedforms in the northeastern continental slope of the South China Sea were investigated by integrating high-resolution multibeam bathymetric data and multichannel seismic profiles. In the area, many canyons are developed, including the Penghu, West Penghu, Jiulong, South Taiwan Shoal and Dongsha canyons. Most of the canyons downslope join the South Taiwan Shoal canyon, and finally merge into the Penghu canyon. Numerous step-like features were recognized within the South Taiwan Shoal and the West Penghu canyons. The features, ranging from 1.2 to 10.0 km in wave length and 5.4 to 80.9 m in wave height, are mostly interpreted as cyclic steps formed by turbidity currents flowing through the canyons based on their morphological and seismic characteristics. The steps align in trains along the canyon thalwegs or scatter in the canyon terraces. Each thalweg train consists of up to 19 continuous cyclic steps and extends up to 100 km in length, and is separated by a slope break into an upper steeper and a lower gentler segments. Steps in the upper segments are characterized by smaller wavelength and chaotic internal reflections, which contrast to those in the lower segments with a lager wavelength and typical upstream-dipping backset reflections. Aided by a simple numerical modeling exercise, we interpreted the features in the upper segments as net-erosional cyclic steps or transitional bedforms between antidunes and cyclic steps, and those in the lower segments as net-depositional cyclic steps. Nine short trains of scours were identified on a terrace of the South Taiwan Shoal canyon. They are oriented parallel to the tributaries draining over the terrace and roughly perpendicular to the main canyon thalweg, and are presumed as resulting from the tributary flows, indicating a complicated flow pattern within the canyon valley. In addition, four large fields of sediment waves were delineated. They are located on the western and southern flanks of

  15. 77 FR 52 - Fisheries of the Northeastern United States; Atlantic Sea Scallop Fishery; Framework Adjustment 23

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-03

    ... measures to: Minimize impacts on sea turtles through the requirement of a turtle deflector dredge; improve.... According to recent research indicating where sea turtle interactions most often occur, the proposed area... loggerheads, but Kemps ridley turtles and one green sea turtle have also been observed to interact...

  16. Bromide content of sea-salt aerosol particles collected over the Indian Ocean during INDOEX 1999

    NASA Astrophysics Data System (ADS)

    Gabriel, R.; von Glasow, R.; Sander, R.; Andreae, M. O.; Crutzen, P. J.

    2002-10-01

    Bromide can be depleted from sea-salt aerosol particles in the marine boundary layer (MBL) and converted to reactive gas-phase species like Br, BrO, and HOBr, which affect ozone chemistry. Air pollution can enhance the bromine release from sea-salt aerosols and thus inject additional bromine into the MBL. During the winter monsoon the northern Indian Ocean is strongly affected by air pollution from the Indian subcontinent and Asia. As part of the Indian Ocean Experiment (INDOEX), aerosol particles were sampled with stacked filter units (SFU) on the NCAR Hercules C-130 aircraft during February-March 1999. We determined the vertical and latitudinal distribution of the major inorganic aerosol components (NH4+, Na+, K+, Mg2+, Ca2+, Cl-, NO3-, SO42-) and the Br- content of the coarse aerosol to examine the role of the bromine release on the gas-phase chemistry in the marine boundary layer over the tropical Indian Ocean. The aerosol mass and composition varied significantly with air mass origin and sampling location. In the northern part of the Indian Ocean (5°-15°N, 66°-73°E), high concentrations of pollution-derived inorganic species were found in the marine boundary layer extending from the sea surface to about 1.2 km above sea level. In this layer, the average mass concentration of all aerosol species detected by our technique was comparable to pollution levels observed in industrialized regions. In the Southern Hemisphere (1°-9°S, 66°- 73°E), the aerosol concentrations rapidly declined to remote background levels. A chloride loss from the coarse aerosol particles was observed in parallel to the latitudinal gradient of the non sea salt SO42- burden. In most of the samples, Br- was depleted from the sea-salt aerosols. However, we found an enrichment in bromide in aerosols affected by air masses originating over strong pollution sources in India (Bombay, Calcutta). In these cases the additional pollution-derived Br from organo-halogen additives in petrol

  17. Interranual variability in horizontal patterns of larval fish assemblages in the northeastern Aegean Sea (eastern Mediterranean) during early summer

    NASA Astrophysics Data System (ADS)

    Isari, Stamatina; Fragopoulu, Nina; Somarakis, Stylianos

    2008-09-01

    Larval fish community structure was studied in the northeastern Aegean Sea (NEA) over an area influenced by the advection of Black Sea water (BSW). Sampling was carried out in early summer during a period of 4 years (2003-2006). Taxonomic composition and abundance presented high variability in space that remained relatively constant among years. Tow depth and indicators of trophic conditions in the upper water column (i.e., zooplankton displacement volume, fluorescence) explained significantly the structure of larval assemblages during all surveys. The northern continental shelf (Thracian and Strymonikos shelf), where a large amount of enriched, low salinity BSW is retained, was dominated by larvae of epipelagic species, mainly anchovy ( Engraulis encrasicolus). Interannual changes in horizontal extension of the BSW seemed to match closely observed changes in the distribution of anchovy larvae. Mesopelagic fish larvae were particularly abundant beyond the continental shelf (over the North Aegean Trough) where a strong frontal structure is created between the low salinity waters of BSW origin and the high salinity waters of the Aegean Sea. Larvae of certain mesopelagic species (e.g., Ceratoscopelus maderensis) may occasionally be transported inshore when the prevailing current meanders towards the coast or feeds anticyclonic gyres over the continental shelf.

  18. Deep-water sediment transport processes in the northeastern South China Sea: Mooring and shipboard-based observations

    NASA Astrophysics Data System (ADS)

    Liu, Z.; Zhao, Y.; Zhang, Y.; Li, J.; Li, X.; Wang, W.; Xu, J.

    2013-12-01

    Six moorings equipped with acoustic doppler current profiler (ADCP), recording current meter (RCM), and sediment trap have been deployed in the northeastern South China Sea at water depths ranging from 1700-3900 m to collect time-series data that can hopefully help better characterize the bottom current system and transport process in the region. Shipboard-based measurements including CTD, transmissometer, optical backscatter (OBS), and in-situ layered suspended particle sampling using large volume pump (LVP) were undertaken along three deep-water transects in the region during two cruises in the spring of 2012 and 2013. Preliminary results show for the first time the presence of continuous and relative stable contour currents and widespread deep-water nepheloid layers in the deep South China Sea. The contour currents flow southwestwards with average speeds of 2-4 cm/s (occasionally up to 11 cm/s) along lower slope of the northern South China Sea at depths of 1700-2500 m. The large-scale sediment waves recorded by high-resolution multibeam bathymetry appear to be related to activities of the contour currents. Intermediate and bottom nepheloid layers with an average suspended particle concentration of 0.6 mg/l are extended from the lower slope to the deep basin of the South China Sea. The intermediate nepheloid layers in depths ranging from 900 to 1100 m are thought to be controlled mainly by the interaction between the North Pacific Intermediate Water and the Pacific Deep Water masses. A sedimentary core (MD01-2905) previously collected on the sediment drift of ODP Site 1144, where three of the mooring systems are located, indicates that 60% of total fine-grained terrigenous sediment budget since the last glacial time have sourced from Taiwan. Our data suggest that the observed contour currents are the major carrier for transporting Taiwan-derived sediments to the northern slope of the South China Sea.

  19. Growth of the Afanasy Nikitin seamount and its relationship with the 85°E Ridge, northeastern Indian Ocean

    NASA Astrophysics Data System (ADS)

    Krishna, K. S.; Bull, J. M.; Ishizuka, O.; Scrutton, R. A.; Jaishankar, S.; Banakar, V. K.

    2014-02-01

    The Afanasy Nikitin seamount (ANS) is a major structural feature (400 km-long and 150 km-wide) in the Central Indian Basin, situated at the southern end of the so-called 85°E Ridge. Combined analyses of new multibeam bathymetric, seismic reflection and geochronological data together with previously described magnetic data provide new insights into the growth of the ANS through time, and its relationship with the 85°E Ridge. The ANS comprises a main plateau, rising 1200 m above the surrounding ocean floor (4800 m), and secondary elevated seamount highs, two of which (lie at 1600 and 2050 m water depths) have the morphology of a guyot, suggesting that they were formed above or close to sea-level. An unbroken sequence of spreading anomalies 34 through 32n.1 identified over the ANS reveal that the main plateau of the ANS was formed at 80-73 Ma, at around the same time as that of the underlying oceanic crust. The 40Ar/39Ar dates for two basalt samples dredged from the seamount highs are consistent, within error, at 67 Ma. These results, together with published results of late Cretaceous to early Cenozoic Indian Ocean plate reconstructions, indicate that the Conrad Rise hotspot emplaced both the main plateau of the ANS and Conrad Rise (including the Marion Dufresne, Ob and Lena seamounts) at 80-73 Ma, close to the India-Antarctica Ridge system. Subsequently, the seamount highs were formed by late-stage volcanism c. 6-13 Myr after the main constructional phase of the seamount plateau. Flexural analysis indicates that the main plateau and seamount highs of the ANS are consistent with Airy-type isostatic compensation, which suggest emplacement of the entire seamount in a near spreading-center setting. This is contrary to the flexural compensation of the 85°E Ridge further north, which is interpreted as being emplaced in an intraplate setting, i.e., 25-35 Myr later than the underlying oceanic crust. Therefore, we suggest that the ANS and the 85°E Ridge appear to be

  20. Growth of the Afanasy Nikitin seamount and its relationship with the 85°E Ridge, northeastern Indian Ocean

    NASA Astrophysics Data System (ADS)

    Krishna, K. S.

    2012-12-01

    The Afanasy Nikitin seamount (ANS) is a major structural feature (400 km-long and 150 km-wide) in the Central Indian Basin, situated at the southern end of the so-called 85°E Ridge. Combined analyses of new multibeam bathymetric, seismic reflection and geochronological data together with previously described magnetic data provide valuable insights into the growth of the ANS through time, and its relationship with the 85°E Ridge. The ANS comprises a main plateau, rising 1200 m above the surrounding ocean floor (4800 m), and secondary elevated seamount highs, two of which (lie at 1600 m and 2050 m water depths) have the morphology of a guyot, suggesting that they were formed above or close to sea-level. An unbroken sequence of spreading anomalies 34 through 31 identified over the ANS reveal that the main plateau of the ANS was formed at 80 - 73 Ma, at the same time as the underlying oceanic crust. The 40Ar/39Ar dates for two basalt samples dredged from the seamount highs are consistent, within error, at 67 Ma. These results, together with published results of late Cretaceous to early Cenozoic Indian Ocean plate reconstructions, indicate that the Conrad Rise hot spot emplaced both the main plateau of the ANS and Conrad Rise (including the Marion Dufresne, Ob and Lena seamounts) at 80-73 Ma, close to the India-Antarctica Ridge system. Subsequently, the seamount highs were formed by late-stage volcanism c. 6 - 13 Myr after the main constructional phase of the seamount plateau. Flexural analysis indicates that the main plateau and seamount highs of the ANS are consistent with Airy-type isostatic compensation, which suggest emplacement of the entire seamount in a near spreading-center setting. This is contrary to the flexural compensation of the 85°E Ridge further north, which is interpreted as being emplaced in an intraplate setting, i.e., 25-35 Myr later than the underlying oceanic crust. Therefore, we conclude that the Afanasy Nikitin seamount and the 85°E Ridge

  1. Freshening of the South Indian Ocean during the Argo period: observations, causes, and impact on regional sea level change

    NASA Astrophysics Data System (ADS)

    Llovel, William; Lee, Tong

    2015-04-01

    Steric sea level change has been identified as one of the major contributors to the regional sea level changes. This contribution varies in space and time. Temperature (thermosteric) contribution to sea level has been found to be generally more important than salinity (halosteric) effect. Based on temperature and salinity data from Argo floats during 2005-2013 and coincident sea level measurements from satellite altimetry, we found that the central-eastern part of the South Indian Ocean stood out in the entire world ocean as a region that had a more dominant halosteric contribution to sea level change. The conspicuously large halosteric contribution was associated with a freshening in the upper few hundred meters. Neither local atmospheric forcing nor halosteric signal transmitted from the Pacific can explain this freshening. An observed strengthening of the Indonesian throughflow since early 2007 and the enhanced precipitation in the Indonesian Seas inferred from various precipitation estimates compounded by strong tidal mixing are the likely causes of the freshening of the South Indian Ocean. The findings also have implications to the potential influence of regional water cycle and ocean currents in the maritime Continent region to sea level changes in the South Indian Ocean prior to the Argo era and sea level projection in the future in response to climate change. Sustained measurements of sea surface salinity from satellites will significantly enhance our capability to study the impact of regional water cycle in the Maritime Continent region to related changes in the marginal seas and the Indian Ocean.

  2. The relationship between Indian Ocean sea-surface temperature and East African rainfall.

    PubMed

    Black, Emily

    2005-01-15

    Knowledge of the processes that control East African rainfall is essential for the development of seasonal forecasting systems, which may mitigate the effects of flood and drought. This study uses observational data to unravel the relationship between the Indian Ocean Dipole (IOD), the El Nino Southern Oscillation (ENSO) and rainy autumns in East Africa. Analysis of sea-surface temperature data shows that strong East African rainfall is associated with warming in the Pacific and Western Indian Oceans and cooling in the Eastern Indian Ocean. The resemblance of this pattern to that which develops during IOD events implies a link between the IOD and strong East African rainfall. Further investigation suggests that the observed teleconnection between East African rainfall and ENSO is a manifestation of a link between ENSO and the IOD. PMID:15598619

  3. 75 FR 38935 - Fisheries of the Northeastern United States; Black Sea Bass Fishery; 2010 Black Sea Bass...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-07

    ... emergency rule to increase the 2010 black sea bass specifications on February 10, 2010 (75 FR 6586). The... (75 FR 6586), NMFS requested, and subsequently received, comments on the increased black sea bass TAL... December 22, 2009 (74 FR 67978), and became effective on January 1, 2010. The final rule implemented a...

  4. Mean Sea Level Derived from Altimetry and Wind-Driven Numerical Models in the Indian Ocean

    NASA Technical Reports Server (NTRS)

    Perigaud, C.; Delecluse, P.; Greiner, E.; Rogel, P.

    1995-01-01

    Wind-driven model skill in simulating sea level variations in the Indian Ocean depends on our knowledge of the mean ocean dynamic topography. This is demonstrated by running the nonlinear or linear version of a shallow-water model driven by observed winds over Geosat and TOPEX periods. Geosat variations are assimilated in the nonlinear shallow-water model with the objective of obtaining topography data.

  5. Relative sea-level change in northeastern Florida (USA) during the last ∼8.0 ka

    NASA Astrophysics Data System (ADS)

    Hawkes, Andrea D.; Kemp, Andrew C.; Donnelly, Jeffrey P.; Horton, Benjamin P.; Peltier, W. Richard; Cahill, Niamh; Hill, David F.; Ashe, Erica; Alexander, Clark R.

    2016-06-01

    An existing database of relative sea-level (RSL) reconstructions from the U.S. Atlantic coast lacked valid sea-level index points from Georgia and Florida. This region lies on the edge of the collapsing forebulge of the former Laurentide Ice Sheet making it an important location for understanding glacio-isostatic adjustment and the history of ice-sheet melt. To address the paucity of data, we reconstruct RSL in northeastern Florida (St. Marys) over the last ∼8.0 ka from samples of basal salt-marsh sediment that minimize the influence of compaction. The analogy between modern salt-marsh foraminifera and their fossil counterparts preserved in the sedimentary record was used to estimate paleomarsh surface elevation. Sample ages were determined by radiocarbon dating of identifiable and in-situ plant macrofossils. This approach yielded 25 new sea-level index points that constrain a ∼5.7 m rise in RSL during the last ∼8.0 ka. The record shows that no highstand in sea level occurred in this region over the period of the reconstruction. We compared the new reconstruction to Earth-ice models ICE 6G-C VM5a and ICE 6G-C VM6. There is good fit in the later part of the Holocene with VM5a and for a brief time in the earlier Holocene with VM6. However, there are discrepancies in model-reconstruction fit in the early to mid Holocene in northeastern Florida and elsewhere along the Atlantic coast at locations with early Holocene RSL reconstructions. The most pronounced feature of the new reconstruction is a slow down in the rate of RSL rise from approximately 5.0 to 3.0 ka. This trend may reflect a significant contribution from local-scale processes such as tidal-range change and/or change in base flow of the St. Marys River in response to paleoclimate changes. However, the spatial expression (local vs. regional) of this slow down is undetermined and corroborative records are needed to establish its geographical extent.

  6. Importance of vertical geochemical processes in controlling the oceanic profiles of dissolved rare earth elements in the northeastern Indian Ocean

    NASA Astrophysics Data System (ADS)

    Nozaki, Yoshiyuki; Alibo, Dia Sotto

    2003-01-01

    Vertical profiles of dissolved rare earth elements (REEs) were obtained in the Bay of Bengal and the Andaman Sea. The REE concentrations at various depths in the Bay of Bengal are the highest in the Indian Ocean. This is attributable ultimately to the large outflow of the Ganges-Brahmaputra and Irrawaddy rivers, but the dissolved REE flux to surface waters alone cannot explain the large and near-constant REE enrichment throughout the entire water column. The underlying fan sediments serve as not a source but a sink for dissolved REE(III)s. Absence of excess 228Ra in the deep waters suggests that lateral input of dissolved REEs from slope sediments is also small in these regions. Partial (<0.3%) dissolution of detrital particles, which are carried by the rivers and lateral surface currents and subsequently settle through the water column, appears to be a predominant source for the dissolved REEs. Vertical profiles showing an almost linear increase with depth are common features for the light and middle REEs everywhere, but their concentration levels are variable from basin to basin and from element to element. This suggests that their oceanic distributions respond quickly to the variation of particle flux and its REE composition through reversible exchange equilibrium with suspended and sinking particles much like the case for Th. The relative importance of the vertical geochemical processes of reversible scavenging over the horizontal basin-scale ocean circulation with passive regeneration like nutrients decreases systematically from the light to the heavy REEs. Using a model, the mean oceanic residence times of REEs in the Bay of Bengal are estimated to range from 37 years for Ce to 140-1510 years for the strictly trivalent REEs. In the deep water of the Andaman Sea, isolated from the Bay of Bengal by the Andaman-Nicobar Ridge (maximum sill depth of ˜1800 m), the REE concentrations are almost uniform presumably due to rapid vertical mixing. The REE

  7. Provenance change of sediment input in the northeastern foreland of Pamir related to collision of the Indian Plate with the Kohistan-Ladakh arc at around 47 Ma

    NASA Astrophysics Data System (ADS)

    Sun, Jimin; Xiao, Wenjiao; Windley, Brian F.; Ji, Weiqiang; Fu, Bihong; Wang, Jiangang; Jin, Chunsheng

    2016-02-01

    The Pamir plateau forms a prominent tectonic salient that marks the western end of the Himalayan orogen containing several terranes that were accreted to Eurasia from the Late Paleozoic to Cenozoic. A detailed knowledge of the tectonic evolution of the Pamir salient during the Cenozoic is important for our understanding of the intracontinental deformation in the western Himalaya. Although the tectonic evolution of the Pamir salient has long been studied, the timing of collision between the Indian Plate and the Kohistan-Ladakh arc is still a matter of debate. We present new U-Pb ages and Hf isotopes of detrital zircons, magnetic fabrics, and stable isotopes from the foreland basin on the northeastern margin of the Pamir that indicate a change in sediment provenance started at about 47 Ma. Sediments in the southwest Tarim Basin were partially derived from the uplifted and eroded Karakoram and Kohistan terranes created by the collision between the Indian Plate and the Kohistan-Ladakh arc at circa 47 Ma, as a result of northward thrusting and propagation of the Indian Plate under Eurasia.

  8. A sea surface salinity dipole mode in the tropical Indian Ocean

    NASA Astrophysics Data System (ADS)

    Zhang, Yuhong; Du, Yan; Qu, Tangdong

    2016-01-01

    Based on the 10 years sea surface salinity (SSS) data from Argo, we identified a salinity dipole mode in the tropical Indian Ocean, termed S-IOD: a pattern of interannual SSS variability with anomalously low-salinity in the central equatorial and high-salinity in the southeastern tropical Indian Ocean. The S-IOD matures in November-December, lagging the Indian Ocean dipole (IOD) mode derived from sea surface temperature (SST) by 2 months. For the period of observations, the S-IOD persists longer than the IOD, until the following September-October. Oscillations of the two S-IOD poles are governed by different processes. Ocean advection associated with equatorial current variability dominates the SSS anomalies of the northern pole, while surface freshwater flux variability plays a key role in the SSS anomalies of the southern pole, where anomalous precipitation is sustained by preformed sea surface temperature anomalies. The S-IOD concurs with the strong IOD, reflecting an ocean-atmosphere coupling through the SST-precipitation-SSS feedback.

  9. [New settlers comb jellies Mnemiopsis leidyi (A. Agassiz) and Beroe ovata Mayer 1912 and their influence on the pelagic ecosystem of the northeastern part of the Black Sea].

    PubMed

    Shiganova, T A; Musaeva, E I; Bulgakova, Iu V; Mirzoian, Z A; MartynIuk, M L

    2003-01-01

    We analyzed the condition of pelagic ecosystem of northeastern Black Sea influenced by expansion of a new settler Beroe ovata in 1999-2001. Expansion of B. ovata considerably decreased the population of another new settler Mnemiopsis leidyi that deformed the Black Sea ecosystem for over a decade. Reduction of M. leidyi population limited its influence on the ecosystem and, consequently, we observed reestablishment of the main components of the Black Sea pelagic ecosystem--zooplankton and fish, their spawn and larvae. The relationship between annual and seasonal variability of the population and biomass of the both new settlers M. leidyi and B. ovata are discussed. PMID:12712584

  10. 76 FR 23940 - Fisheries of the Northeastern United States; Atlantic Sea Scallop Fishery; Framework Adjustment 22

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-29

    ... measures implemented through Framework 21 (75 FR 36559; June 28, 2010), the Council proposed this trip... schedule that was implemented through Framework 16 to the FMP (69 FR 63460; November 2, 2004). The Council... (LAGC) fleets; open area days-at-sea (DAS) and Sea Scallop Access Area (access area) trip...

  11. 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...

  12. Seasonal and interannual changes in zooplankton community in the coastal zone of the North-Eastern Black Sea.

    NASA Astrophysics Data System (ADS)

    Nikishina, A. B.; Arashkevich, E. G.; Louppova, N. E.; Soloviev, K. A.

    2009-04-01

    The phenological response of zooplankton community is a result of simultaneous effect of several factors: feeding conditions, predation abundance, periods of reproduction of common species and hydrodynamic regime. The Black sea ecosystem is one of the best studied in the world, otherwise there is still some illegibility about ecosystem functioning and especially about environmental factors influence on zooplankton dynamics. For the last twenty years pelagic system of the Black Sea has changed dramatically. The invasion of ctenophore Mnemiopsis leidyi in the middle of eighties caused significant decrease in zooplankton biomass. It also altered plankton structure and shifted periods of mass reproduction of the abundant species and biomass maximums. For instance, before the invasion of Mnemiopsis the maximum of zooplankton biomass was observed in autumn (data by A. Pasternak, 1983), and after that the maximum moved to the spring (data by V.S. Khoroshilov, 1999). The incursion of ctenophore Beroe ovata feeding on Mnemiopsis in the nineties has led to the enhancement of zooplankton community. Although the detailed analysis of seasonal zooplankton dynamics wasn't performed in the recent years. The object of our research was to study seasonal and interannual changes in zooplankton community in the coastal area of the North-Eastern Black Sea. Analysis of interannual, seasonal and spatial changes in zooplankton distribution, abundance and species composition along with age structure of dominant populations were performed based on investigations during 2005-2008 years in the North-Eastern Black Sea. Plankton samples were obtained monthly since June 2005 till December 2008. Plankton was collected at three stations at depths 25m, 50m and 500-1000m along the transect from the Blue Bay to the open sea. Sampling of gelatinous animals was conducted in parallel to the zooplankton sampling. Simultaneously with plankton sampling CTD data were obtained. The feeding conditions were

  13. Philinidae, Laonidae and Philinorbidae (Gastropoda: Cephalaspidea: Philinoidea) from the northeastern Pacific Ocean and the Beaufort Sea (Arctic Ocean).

    PubMed

    Valdés, Ángel; Cadien, Donald B; Gosliner, Terrence M

    2016-01-01

    Based on morphological data a total of nine native species of Philinidae are recognized from the northeastern Pacific including the Bering Sea and the adjacent Arctic Ocean (Beaufort Sea). Four of them have been previously described: Philine ornatissima Yokoyama, 1927, Philine bakeri Dall, 1919, Philine polystrigma (Dall, 1908), and Philine hemphilli Dall, 1919. Five of them are new and described herein: Philine mcleani sp. nov., Philine baxteri sp. nov., Philine malaquiasi sp. nov., Philine wareni sp. nov., and Philine harrisae sp. nov. These species display a substantial degree of variation in internal and external morphological traits (i.e., presence/absence of gizzard plates, different radular structure and tooth morphology, various reproductive anatomical features) and it is likely that they belong to different clades (genera). However, in the absence of a comprehensive phylogeny for Philine, they are here provisionally regarded as Philine sensu lato. In addition to the nine native species, two introduced species: Philine orientalis A. Adams, 1854 and Philine auriformis Suter, 1909 are here illustrated and compared to the native species to facilitate identification. Finally, two species previously considered members of Philinidae are examined anatomically and confirmed as members of Laonidae, Laona californica (Willett, 1944) and Philinorbidae, Philinorbis albus (Mattox, 1958), based on morphological data. PMID:27515632

  14. Sea surface height anomaly and upper ocean temperature over the Indian Ocean during contrasting monsoons

    NASA Astrophysics Data System (ADS)

    Gera, Anitha; Mitra, A. K.; Mahapatra, D. K.; Momin, I. M.; Rajagopal, E. N.; Basu, Swati

    2016-09-01

    Recent research emphasizes the importance of the oceanic feedback to monsoon rainfall over the Asian landmass. In this study, we investigate the differences in the sea surface height anomaly (SSHA) and upper ocean temperature over the tropical Indian Ocean during multiple strong and weak monsoons. Analysis of satellite derived SSHA, sea surface temperature (SST) and ocean reanalysis data reveals that patterns of SSHA, SST, ocean temperature, upper ocean heat content (UOHC) and propagations of Kelvin and Rossby waves differ during strong and weak monsoon years. During strong monsoons positive SSH, SST and UOHC anomalies develop over large parts of north Indian Ocean whereas during weak monsoons much of the north Indian Ocean is covered with negative anomalies. These patterns can be used as a standard tool for evaluating the performance of coupled and ocean models in simulating & forecasting strong and weak monsoons. The rainfall over central India is found to be significantly correlated with SSHA over the regions (Arabian Sea and West central Indian Ocean and Bay of Bengal) where SSHA is positively large during strong monsoons. The SST-SSHA correlation is also very strong over the same area. The study reveals that much convection takes place over these regions during strong monsoons. In contrast during weak monsoons, convection takes place over eastern equatorial region. These changes in SST are largely influenced by oceanic Kelvin and Rossby waves. The Rossby waves initiated in spring at the eastern boundary propagate sub-surface heat content in the ocean influencing SST in summer. The SST anomalies modulate the Hadley circulation and the moisture transport thereby contributing to rainfall over central India. Therefore oceanic Kelvin and Rossby waves influence the rainfall over central India.

  15. Timing of the Last-Interglacial High Sea Level on the Seychelles Islands, Indian Ocean

    NASA Astrophysics Data System (ADS)

    Israelson, Carsten; Wohlfarth, Barbara

    1999-05-01

    Corals from the Seychelles Islands, Indian Ocean, occur mainly as small coralline algae-vermetid remnants found in cavities adhering to the rock surface, and they rarely attain more than 2 m2in area. Samples ofGoniastreaandPoritesfrom elevations between 1.7 and 6 m above present mean sea level were dated by TIMS238U-234U-230Th techniques. The ages from well-preserved corals lie between 131,000 and 122,000 yr B.P., in agreement with most other observations of the last-interglacial sea level. Field evidence and dating from high marine limestones from two sections at La Digue Island indicate a period of coral buildup until 131,000 yr B.P., followed by a drop in sea level between 131,000 and 122,000 yr B.P.

  16. The benthic ecosystem of the northeastern Chukchi Sea: An overview of its unique biogeochemical and biological characteristics

    NASA Astrophysics Data System (ADS)

    Dunton, Kenneth H.; Grebmeier, Jacqueline M.; Trefry, John H.

    2014-04-01

    In February 2008, Lease Sale 193 generated renewed interest for oil and gas exploration in the northeastern Chukchi Sea and prompted a series of studies designed to increase our scientific knowledge of this biologically rich area. We present in this special issue the results from major field expeditions during open-water periods in the summers of 2009 and 2010. Our work focused on the biological and chemical characteristics of the benthos with the goal of establishing a strong baseline for assessing future changes that may occur in response to (1) impacts from oil and gas activities, and (2) variations in hydrography, circulation or ice retreat associated with climatic change. We found concentrations of aliphatic hydrocarbons, polycyclic aromatic hydrocarbons (PAHs), and 17 trace metals in sediments at natural background levels throughout the study area except at two previous (1989) drilling sites; there was no evidence that showed bioaccumulation of these substances above natural concentrations. Inorganic-N was recycled within one day throughout the water column, with evidence of substantial remineralization of organic matter in the sediments. Active efflux of sediment NO3- supports water column primary production that, in turn, sustains a rich benthos dominated by crustaceans and echinoderms that also receive, based on isotopic evidence, a benthic carbon subsidy. Benthic food webs are complex, with high trophic redundancy based on the diversity of both infaunal and epifaunal populations. The highest trophic levels in the benthos were dominated by predatory gastropods. Comparisons of gray whale and walrus distributions from aerial sightings showed a large difference between the two study years relative to the more stable benthic prey base for these animals over that period. A nearly ice-free shelf by early summer 2009 compared to 2010 revealed that walrus distributions were more closely linked to sea ice rather than to benthic prey items, indicating that rapid

  17. 75 FR 59154 - Fisheries of the Northeastern United States; Black Sea Bass Fishery; 2010 Black Sea Bass...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-27

    ... 7, 2010 (75 FR 38935), as part of the extension to the emergency rule to increase the 2010 black sea... published in the Federal Register on July 7, 2010 (75 FR 38935). On page 38935 of that rule, the commercial... on February 10, 2010 (75 FR 6586). However, the extension to the emergency rule...

  18. 75 FR 6586 - Fisheries of the Northeastern United; Black Sea Bass Fishery; 2010 Black Sea Bass Specifications...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-10

    ... black sea bass specifications was published in the Federal Register on December 22, 2009 (74 FR 67978...; 62 FR 44421) and finds the Council(s request meets both the criteria and justifications for invoking... 516 d at 74 FR 67978, Decembe r 22, 2009 Emergenc 4,500,000 2,041 800,000 363 3,700,000 1,678...

  19. Seasonal and interannual variation in the planktonic communities of the northeastern Chukchi Sea during the summer and early fall

    NASA Astrophysics Data System (ADS)

    Questel, Jennifer M.; Clarke, Cheryl; Hopcroft, Russell R.

    2013-09-01

    We analyzed the seasonal and interannual variability of the planktonic communities in a densely sampled region of the northeastern Chukchi Sea as part of a multidisciplinary ecosystem study from 2008 to 2010. Observations of chlorophyll-a, inorganic macronutrients, and zooplankton (using both 150-μm and 505-μm mesh nets) were made within two 900-NM 2 grids (Klondike and Burger) at high spatial resolution three times each in 2008 and 2009, with a third grid (Statoil) sampled twice in 2010. Sea-ice conditions prior to sampling varied notably during the study: seasonal sea ice retreat was earlier and sea-surface temperatures (SSTs) were warmer in 2009 than in 2008, whereas SSTs for 2010 were intermediate between the 2008 and 2009 values. Eighty taxonomic categories of zooplankton, including 11 meroplanktonic categories, were recorded, with the greatest diversity found within the copepods (25 species), followed by the cnidarians (11 species). All species are typical for the region and most are seeded from the Bering Sea. A seasonal progression of the community structure was apparent over each survey area and was likely influenced by temperature. Cold oceanographic conditions in 2008 likely slowed growth and development of the zooplankton, such that holozooplankton abundance averaged 2389 and 106 individuals m-3 and biomass averaged 10.5 and 8.3 mg DW m-3 in the 150- and 505-μm nets, respectively. An early phytoplankton bloom in 2009 apparently supported a zooplankton community of greater abundance, but moderate biomass, averaging 6842 and 189 individuals m-3, and 16.3 and 7.0 mg DW m-3 in the 150- and 505-μm nets, respectively. Highest zooplankton abundance and biomass values among the three years occurred in 2010: 7396 and 198 individuals m-3 and 102.9 and 33.5 mg DW m-3 in the 150- and 505-μm nets, respectively. Holozooplankton biomass changes were driven by increases in large-bodied, lipid-rich copepods. The contribution of meroplankton was substantial in this

  20. The effect of zonal gradients of sea surface temperature on the Indian Ocean winter monsoon

    NASA Technical Reports Server (NTRS)

    Cohen, C.

    1981-01-01

    Several global climate simulations by the 7-layer, 8 x 10 GISS climate model were designed to test the contributions of various surface boundary conditions to the global climate. The model was run with the sun fixed at a perpetual January. In a comparison of run #5, in which realistic January surface boundary conditions were used, with run #4, which was the same except that a zonally symmetric climatological January sea surface temperature (SST) field was used, one of the results was that run #5 provided a better simulation of the Indian Ocean monsoon. A further comparison of the wind fields over the Indian Ocean that were generated by these two model runs is presented.

  1. Sea level and coral atolls: Late holocene emergence in the Indian Ocean

    SciTech Connect

    Woodroffe, C. ); McLean, R. ); Polach, H.; Wallensky, E. )

    1990-01-01

    The Cocos (keeling) Islands in the eastern Indian Ocean were visited by Charles Darwin, who described geomorphological evidence that he considered supported his subsidence theory of coral-reef development. However, several other accounts of the reef islands have questioned Darwin's interpretation, and have suggested that a conglomerate platform that underlies most of the reef islands may indicate recent emergence of the atoll. Radiocarbon ages on corals from this conglomerate platform, reported here, indicate that it formed in the late Holocene. Fossil in situ microatolls above present upper coral growth limits, the elevation of associated beachrock, and the morphological similarity of the conglomerate platform to the present reef-flat deposits indicate a late Holocene sea level above the present relative to the atoll. The atoll has undergone at least 0.5 m of emergence since about 3000 yr B.P. This represents the first radiometrically dated evidence of Holocene emergence from islands in the eastern or central Indian Ocean.

  2. 77 FR 73957 - Fisheries of the Northeastern United States; Atlantic Sea Scallop Fishery; Closure of the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-12

    ... Adjustment 22 to the Scallop FMP (Framework 22) (76 FR 43774; July 21, 2011), which used 2010 scallop... policy guidelines for the use of emergency rules (62 FR 44421; August 21, 1997) specify the following... United States; Atlantic Sea Scallop Fishery; Closure of the Elephant Trunk Area AGENCY: National...

  3. STS-48 ESC Earth observation of Antarctic sea ice and clouds over Indian Ocean

    NASA Technical Reports Server (NTRS)

    1991-01-01

    STS-48 Earth observation taken aboard Discovery, Orbiter Vehicle (OV) 103, is of Antarctic sea ice and clouds over the southern Indian Ocean. Considerable detail can be seen in the ice field. The distribution of the ice field as seen through the breaks in the clouds is complex, and according to NASA scientists studying the STS-48 imagery, it likely contains information about ocean currents. The image was captured using an electronic still camera (ESC), was stored on a removable hard disk or small optical disk, and was converted to a format suitable for downlink transmission. The ESC documentation was part of Development Test Objective (DTO) 648, Electronic Still Photography.

  4. Interactions of habitat complexity and environmental characteristics with macrobenthic community structure at multiple spatial scales in the northeastern Chukchi Sea

    NASA Astrophysics Data System (ADS)

    Blanchard, Arny L.; Feder, Howard M.

    2014-04-01

    Spatial trends in macrobenthic communities from the northeastern Chukchi Sea are evaluated to understand how ecological processes influencing macrofauna differ between small and large scales. Macrobenthos was sampled with a van Veen grab in a mesoscale study (distances ~10-200 km) in 1986 and in a midscale study (distances ~2-20 km) in 2008-2010. Common field and laboratory methods allowed for a direct comparison of the data sets. Environmental characteristics influencing spatial structures of macrobenthic communities varied with the scale of sampling. Midscale variations of macrofaunal community structure in the 2008-2010 study were associated with the local topographic variations resulting in an enhanced carbon deposition and a greater biological production; total density increased with the increasing water depth and organic carbon. Mesoscale environmental gradients in the 1986 study, reflecting physical dynamics, water mass movements, and oceanographic conditions, were associated with an inshore to offshore faunal gradient as density declined with greater water depth. Differences in environmental and biological community relationships between scales included shifts in the regression relationships between water depth and macrobenthic density with declining density at the mesoscale and the increasing density with greater depth at the midscale. Biomass declined more sharply with increased bottom-water temperature in the midscale study than in the mesoscale investigation. Multivariate analyses demonstrated similar shifts in the relationship between biotic summary measures and water depth. Increased benthic production is noted in other areas of the Chukchi Sea in association with topographic variations, and such variations may be predictive of increased benthic production. Ecologically significant changes in relationships of environmental and biological gradients between spatial scales indicate the need for small-scale sampling to detect long-term change in marine

  5. Phytoplankton dynamics driven by vertical nutrient fluxes during the spring inter-monsoon period in the northeastern South China Sea

    NASA Astrophysics Data System (ADS)

    Li, Q. P.; Dong, Y.; Wang, Y.

    2016-01-01

    A field survey from the coastal ocean zones to the offshore pelagic zones of the northeastern South China Sea (nSCS) was conducted during the inter-monsoon period of May 2014 when the region was characterized by prevailing low-nutrient conditions. Comprehensive field measurements were made for not only hydrographic and biogeochemical properties but also phytoplankton growth and microzooplankton grazing rates. We also performed estimations of the vertical turbulent diffusivity and diffusive nutrient fluxes using a Thorpe-scale method and the upwelling nutrient fluxes by Ekman pumping using satellite-derived wind stress curl. Our results indicated a positive correlation between the integrated phytoplankton chlorophyll a and vertical nutrient fluxes in the offshore region of the nSCS during the study period. We generally found an increasing role of turbulent diffusion but a decreasing role of curl-driven upwelling in vertical transport of nutrients from the coastal ocean zones to the offshore pelagic zones. Elevated nutrient fluxes near Dongsha Islands supported high new production leading to net growth of the phytoplankton community, whereas the low fluxes near the southwest of Taiwan had resulted in a negative net community growth leading to decline of a surface phytoplankton bloom. Overall, phytoplankton dynamics in the large part of the nSCS could be largely driven by vertical nutrient fluxes including turbulent diffusion and curl-driven upwelling during the spring inter-monsoon period.

  6. Epipelagic mesozooplankton succession and community structure over a marine ouffall area in the northeastern South China Sea.

    PubMed

    Tseng, Li Chun; Kumar, Ram; Dahms, Hans Uwe; Chen, Chun Te; Chen, Qing Chao; Hwang, Jiang Shiou

    2008-05-01

    This study analyses distribution and abundance patterns of mesozooplankton communities at 13 stations in the coastal waters over a marine outfall area in the northeastern South China Sea. Cruises were conducted in March, June and September 2002, and plankton samples were collected with a 333 microm North Pacific net. The Mesozooplankton was dominated by calanoid Copepods, Cladocera, Chaetognatha and Pteropoda. Stations located near the entrance of the harbor provided a relatively higher abundance of Noctilucales and Radiolarians. In total, 20 zooplankton groups were identified in which, Calanoida, Cladocera, Chaetognatha, Pteropoda, Poecilostomatoida and Appendicularia comprised 92.77% of the total zooplankton abundance. Copepoda dominated in all three cruises, comprising 65.32% of the total mesozooplankton abundance. Samples collected in June recorded higher mesozooplankton abundance than March and September samples. Onshore stations recorded higher BOD values, higher abundance of Noctilucales and Radiolarians and a relativelylower abundance of the overall mesozooplankton. Total mesozooplankton abundance did not correlate significantly with temperature, pH, or dissolved oxygen, but correlated negatively with BOD. PMID:18972677

  7. Interannual modulation of eddy kinetic energy in the northeastern South China Sea as revealed by an eddy-resolving OGCM

    NASA Astrophysics Data System (ADS)

    Sun, Zhongbin; Zhang, Zhiwei; Zhao, Wei; Tian, Jiwei

    2016-05-01

    Interannual modulation of eddy kinetic energy (EKE) in the northeastern South China Sea (NE-SCS) is investigated based on outputs of an eddy-resolving oceanic general circulation model between 1980 and 2014. The EKE displays distinct interannual modulations with periods between 1.5 and 7 years. The maximum peak-to-trough amplitude of the interannual modulation occurred during period 2004-2005, which was about 1.5-fold the time-mean EKE level. Further analysis suggested that interannual variability of EKE in the NE-SCS is primarily modulated by the Luzon Strait transport (LST). During high-EKE years, the LST increases corresponding to a strengthened Kuroshio intrusion. The strengthened Kuroshio intrusion enhances the baroclinic instability of current in the NE-SCS and thus leads to a strong EKE. The reverse is true during low-EKE years when LST is smaller. Influences of ENSO and Pacific mesoscale eddies on the interannual modulation of LST are also discussed in this study.

  8. Distribution of Holocene deep-sea benthonic foraminifera in the southwest Indian Ocean

    NASA Astrophysics Data System (ADS)

    Corliss, Bruce H.

    1983-02-01

    The distribution of deep-sea benthonic foraminifera in core top samples from the southwest Indian Ocean is examined. Principal component analysis reveals two major assemblages. One assemblages between 3600 and 4800-m water depth is dominated by Episominella umbonifera and is associated with cold ( θ = -0.3 to 0.8°C), low salinity (34.66 to 34.72 × 10 -3) Antarctic Bottom Water in the Crozet Basin, in fracture zones, and on the flanks of the Southwest Indian Ridge. A second assemblage, dominated by Planulina wuellerstorfi, Globocassidulina subglobasa, Astrononion echolsi and Pullenia bulloides, is between 1600 and 3800 m on the Crozet Plateau, Madagascar Ridge, Central Indian Ridge, and Southwest Indian Ridge and is associated with relatively warm ( θ = 0.8 to 2.6°C), high salinity (34.72 to 34.76 × 10 -3) North Atlantic Deep Water. The third principal component divides the P. wuellerstorfi assemblage into two subgroups. One is dominated by Epistominella exigua, P. bulloides, P. wuellerstorfi, and A. echolsi and a second is dominated by G. subglobosa. The distribution of the E. umbonifera assemblage and previous hydrographic studies suggest that AABW flows as a western boundary contour current in the Crozet Basin and penetrates fracture zones in the Southwest Indian Ridge between 55 and 57°E and near 66°E as it travels northward into the Madagascar and Mascarene basins. The faunal-water mass associations from the southeast Indian Ocean are compared; the most notable faunal difference is the absence of Uvigerina as a dominant taxon in the southwest Indian Ocean. A comparison of dissolved oxygen and Uvigerina data shows that oxygen is not a major influence upon the distribution of Uvigerina. A correlation analysis of the faunal data and water depth, potential temperature, in situ temperature, salinity, dissolved oxygen, and 1 - Ω, an index of calcium carbonate undersaturation, was carried out to determine the relationships between fauna and hydrography. The

  9. Environmental policy in the north-eastern sector of the Black sea coast

    NASA Astrophysics Data System (ADS)

    Kosyan, Ruben; Godin, Evgenii; Kosyan, Alisa

    2015-04-01

    Active economic development of the Black Sea East coastal zone has started in the beginning of 20-th century. Those days the pebble taken from beaches was used for construction of buildings, rail and motor roads. Active consumption of pebble from the beaches and river banks had caused a sharp increase of sea shores abrasion and washout rate, number of landslides had also increased. Contemporary Caucasian shores of Black Sea are being developed under increasing man-caused load. Favorable natural conditions, their variety and uniqueness determine the exceptional role of these shores as very important recreational zone of Russian South. Waste urbanized areas, agricultural territories and National Parks are located in immediate neighborhood with the sea. Important industrial facilities and federal and international communi- cations, including major seaports are located in the shore zone. At present time major gas and oil transportation facilities are commissioned and being constructed in the area. Due to the change of geopolitical situation the Russian shoreline had significantly reduced in comparison with Soviet period, especially in most developed regions. Large resort complexes in Georgia, Crimea and Baltic area were lost. Russia had also lost many major seaports that, under conditions of structural change of economy and export growth, had caused the necessity of building new industrial facilities in the Black Sea coastal zone, and, consequently, had stimulated active human invasion into natural coastal processes. At the time being, a major part (three hundred nine kilometers) of Black Sea coast within Russian sector is subject to abrasion and landslide processes. Abrasion process and beaches wash-out, landslides cause destruction of industrial and transport facilities, living and public buildings, resort complexes and valuable agricultural areas. In this light, the challenge of estimation of effective methods of shores protection against wave-induced erosion

  10. Deglacial temperature patterns in the Arabian Sea and mechanisms for Indian monsoon failure

    NASA Astrophysics Data System (ADS)

    Tierney, J. E.; Pausata, F. S. R.; deMenocal, P. B.

    2015-12-01

    Both paleoclimate data and climate model simulations demonstrate that the Indian monsoon system responds to remote coolings in the North Atlantic. The textbook examples are the stadial events associated with the last deglaciation — the Younger Dryas and Heinrich Stadial 1 — when the monsoon weakened dramatically and caused drying throughout the Indian Ocean rim. The mechanism by which the North Atlantic influences the monsoon system is not completely clear: locally cool SSTs, increases in continental albedo, and southward migration of the intertropical convergence zone have all been raised as possibilities. Here we synthesize biomarker and foraminiferal estimates of temperature to study the evolution of the Arabian Sea water column during the deglaciation and test hypotheses of monsoon failure during stadials. Alkenone and Mg/Ca data clearly indicate that the Arabian Sea cools during the YD and H1, although H1 cooling is partly obscured by the overall warming trend associated with orbital forcing and rising greenhouse gases. In contrast, TEX86 data record warmings during the YD and H1. The stark difference between the TEX86 response and the alkenone and foraminiferal data, as well as comparison with climate model simulations, indicates that TEX86 is most likely acting as a subsurface temperature proxy in the Arabian Sea over these timescales. Taken together, the paleoclimate data describe a pattern of surface cooling and subsurface warming in response to North Atlantic cooling. This oceanographic response is in excellent agreement with both timeslice and transient model simulations spanning the last deglaciation, and strongly supports the hypothesis that locally cool SSTs are a requisite for monsoon failure. Furthermore, subsurface warming causes a destratification of the Arabian Sea water column and provides a mechanism for previously observed reductions in productivity during stadial events.

  11. A ˜25 ka Indian Ocean monsoon variability record from the Andaman Sea

    NASA Astrophysics Data System (ADS)

    Rashid, H.; Flower, B. P.; Poore, R. Z.; Quinn, T. M.

    2007-10-01

    Recent paleoclimatic work on terrestrial and marine deposits from Asia and the Indian Ocean has indicated abrupt changes in the strength of the Asian monsoon during the last deglaciation. Comparison of marine paleoclimate records that track salinity changes from Asian rivers can help evaluate the coherence of the Indian Ocean monsoon (IOM) with the larger Asian monsoon. Here we present paired Mg/Ca and δ 18O data on the planktic foraminifer Globigerinoides ruber (white) from Andaman Sea core RC12-344 that provide records of sea-surface temperature (SST) and δ 18O of seawater (δ 18O sw) over the past 25,000 years (ka) before present (BP). Age control is based on nine accelerator mass spectrometry (AMS) dates on mixed planktic foraminifera. Mg/Ca-SST data indicate that SST was ˜3 °C cooler during the last glacial maximum (LGM) than the late Holocene. Andaman Sea δ 18O sw exhibited higher than present values during the Lateglacial interval ca 19-15 ka BP and briefly during the Younger Dryas ca 12 ka BP. Lower than present δ 18O sw values during the BØlling/AllerØd ca 14.5-12.6 ka BP and during the early Holocene ca 10.8-5.5 ka BP are interpreted to indicate lower salinity, reflect some combination of decreased evaporation-precipitation (E-P) over the Andaman Sea and increased Irrawaddy River outflow. Our results are consistent with the suggestion that IOM intensity was stronger than present during the BØlling/AllerØd and early Holocene, and weaker during the late glaciation, Younger Dryas, and the late Holocene. These findings support the hypothesis that rapid climate change during the last deglaciation and Holocene included substantial hydrologic changes in the IOM system that were coherent with the larger Asian monsoon.

  12. Changes in Cancer Incidence Patterns among a Northeastern American Indian Population: 1955-1969 versus 1990-2004

    ERIC Educational Resources Information Center

    Mahoney, Martin C.; Va, Puthiery; Stevens, Adrian; Kahn, Amy R.; Michalek, Arthur M.

    2009-01-01

    Purpose: This manuscript examines shifts in patterns of cancer incidence among the Seneca Nation of Indians (SNI) for the interval 1955-1969 compared to 1990-2004. Methods: A retrospective cohort design was used to examine cancer incidence among the SNI during 2 time intervals: 1955-1969 and 1990-2004. Person-years at risk were multiplied by…

  13. Assessment Of Sea Surface Salinity Obtain From SMOS And Aquarius Satellites Over Indian Ocean

    NASA Astrophysics Data System (ADS)

    Calla, O. P. N.; Dadhich, Harendra Kumar; Singhal, Shruti

    2013-12-01

    In this paper, assessment is done of Sea Surface Salinity (SSS) obtained from both SMOS and Aquarius satellites for couple of months over Indian Ocean (IO). The SSS values of the Southern Indian Ocean (SIO) are being investigated as the North Indian Ocean (NIO) is found much corrupted with the Radio Frequency Interference and even due to large variability of SSS in IO; the study area has been divided into different sub regions. The data of both the satellites at same location and of same processing level that is Level-2 have been procured and evaluated. The resolution factor is also being taken care for both onboard sensors. The resolution of SMOS L2 data products [1] is 15 X 15 Km and for Aquarius there are three different resolutions according to the BEAM's. BEAM 1 has a resolution of 76 X 94 Km, BEAM 2 has 84X120Km and BEAM3 has 96X156Km. The data have been averaged of SMOS [2] in the same way so as to match up with Aquarius resolution. By this paper we want to convince the readers that measuring SSS from space is a practical idea. SSS remote sensing now bears no more scientific perils than other remote sensing techniques did in their formative years. Advancing technology with proper resources has significantly reduced the errors.

  14. The genus Litophyton Forskål, 1775 (Octocorallia, Alcyonacea, Nephtheidae) in the Red Sea and the western Indian Ocean

    PubMed Central

    van Ofwegen, Leen P.

    2016-01-01

    Abstract The Litophyton species of the Red Sea and the western Indian Ocean are revised, which includes species previously belonging to the genus Nephthea, which is synonymized with Litophyton. A neotype for both Litophyton arboreum, the type species of Litophyton, and Nephthea chabrolii, the type species of Nephthea, are designated. The new species Litophyton curvum sp. n. is described and depicted, and a key to all Litophyton species is provided. Of the 26 species previously described from the western Indian Ocean and Red Sea, 13 species are considered valid and 13 have been synonymized or placed in other genera. PMID:27103869

  15. Mercury in the northeastern Chukchi Sea: Distribution patterns in seawater and sediments and biomagnification in the benthic food web

    NASA Astrophysics Data System (ADS)

    Fox, Austin L.; Hughes, Emily A.; Trocine, Robert P.; Trefry, John H.; Schonberg, Susan V.; McTigue, Nathan D.; Lasorsa, Brenda K.; Konar, Brenda; Cooper, Lee W.

    2014-04-01

    Mercury contamination in the atmosphere, snow and marine mammals of the Arctic has been a continuing environmental concern and the focus of many investigations. Much less is known about the distribution of Hg in seawater, sediments and organisms from lower trophic levels in the Arctic, especially the Chukchi Sea. The onset of sea-ice retreat, severe coastal erosion, enhanced primary productivity and offshore energy development in the northeastern Chukchi Sea (NECS) signal changes to a system for which we have limited data for potentially toxic chemicals. To help us better understand and explain any future changes, we present here a combined data set for Hg in seawater, sediments and the following organisms from the NECS: amphipods (Ampelisca macrocephala), clams (Astarte borealis), snow crabs (Chionoecetes opilio), arctic cod (Boreogadus saida) and whelks (Buccinum spp. and Neptunea heros). Concentrations of total dissolved Hg (THgd) averaged (±standard deviation) 2.8±1.4 pM in the NECS, ~2 times greater than values of 1.5±0.5 pM for the Bering Strait. Overall, consistently lower concentrations of THgd were found at depths with markedly higher concentrations of chlorophyll a. Concentrations of total Hg (THg) in sediments from the NECS averaged 31±10 ng g-1, correlated well with silt+clay, Al and TOC, and showed a long-term record consistent with the natural, background environment. Very localized occurrences of sediment with elevated THg concentrations were identified near two exploratory drilling sites where drilling mud and formation cuttings were discharged in 1989. Concentrations of sediment monomethylmercury (MMHg) averaged 0.15±0.07 ng g-1 and accounted for only 0.43±0.17% of the sediment THg. The lowest average value (± standard error) for THg in biota was found for A. borealis at 44±4 ng g-1 dry weight (d. wt.) with 33% of the THg present as MMHg. The highest average values for THg were identified for the whelks N. heros (195±29 ng g-1, d. wt) and

  16. Fungi in deep-sea sediments of the Central Indian Basin

    NASA Astrophysics Data System (ADS)

    Damare, Samir; Raghukumar, Chandralata; Raghukumar, S.

    2006-01-01

    Although a great amount of information is available on bacteria inhabiting deep-sea sediments, the occurrence of fungi in this environment has been poorly studied and documented. We report here the occurrence of fungi in deep-sea sediments from ˜5000 m depth in the Central Indian Basin (9-16°S and 73-76°E). A total of 181 cultures of fungi, most of which belong to terrestrial sporulating species, were isolated by a variety of isolation techniques. Species of Aspergillus and non-sporulating fungi were the most common. Several yeasts were also isolated. Maximum species diversity was observed in 0-2 cm sections of the sediment cores. Direct staining of the sediments with Calcofluor, a fluorescent optical brightener, revealed the presence of fungal hyphae in the sediments. Immunofluorescence using polyclonal antibodies raised against a deep-sea isolate of Aspergillus terreus (# A 4634) confirmed its presence in the form of hyphae in the sub-section from which it was isolated. A total of 25 representative species of fungi produced substantial biomass at 200 bar pressure at 30° as well as at 5 °C. Many fungi showed abnormal morphology at 200 bar/5 °C. A comparison of terrestrial isolates with several deep-sea isolates indicated that the former could grow at 200 bar pressure when growth was initiated with mycelial inocula. However, spores of a deep-sea isolate A. terreus (# A 4634), but not the terrestrial ones, showed germination at 200 bar pressure and 30 °C. Our results suggest that terrestrial species of fungi transported to the deep sea are initially stressed but may gradually adapt themselves for growth under these conditions.

  17. Simulation of Nonlinear Internal Wave Generation in the Northeastern South China Sea

    NASA Astrophysics Data System (ADS)

    Zhang, Z.; Fringer, O. B.

    2006-12-01

    Large-amplitude nonlinear internal waves (NLIW) in the South China Sea (SCS) are hypothesized to be generated by the interaction of barotropic ocean tides with irregular topography on the eastern end of the sea, but because of a lack of detailed in-situ measurements, the exact location and mechanism remain unclear. To improve our understanding of NLIW generation, a high-resolution numerical simulation is employed with a three-dimensional nonhydrostatic unstructured grid Navier-Stokes simulator (SUNTANS). Both the Luzon Strait and Dongsha Islands are contained in our simulation domain to investigate the entire life cycle of NLIW, including tide-topography interaction (generation and dissipation), tide conversion and propagation. By imposing currents associated with nine tidal components obtained with the OSU Tidal Inversion Software (OTIS) over a 10-day spring tidal period in June 2005 and initializing the 950 km by 550 km domain with a representative summer stratification, we analyze results of east-west (u component) velocity profiles and temperature contours along several transects that cross the Batan Islands in the Luzon Strait, the Dongsha atoll, and mooring sites of recent field observations. These are analyzed in order to identify locations of NLIW generation, to examine the propagation characteristics of NLIW, and to determine how the properties of NLIW change as they propagate from their generation site at the Luzon Strait to the Dongsha atoll. Time series of model results are compared with and verified by data obtained in a 2005 SCS field campaign.

  18. Model study of the Miocene Mediterranean Sea and Paratethys: closure of the Indian gateway

    NASA Astrophysics Data System (ADS)

    de la Vara Fernandez, Alba; Meijer, Paul Th.; Wortel, Rinus M. J.

    2013-04-01

    The proto-Mediterranean Sea and Paratethys were both connected to the Indian Ocean until the Middle Miocene, when the convergence of the Eurasian plate and African-Arabian plate caused the constriction and closure of the Indian gateway. This interrupted the water exchange with the Indian Ocean and gave birth to the present-day Mediterranean basin. Although there are lots of uncertainties concerning the timing of the closure and the consequences that this entailed, it is broadly accepted that it had had a large effect on water properties and ocean dynamics on the regional and global scales, and in that way may have also played a role in the evolution of climate. While, from a modeling perspective, considerable research has been devoted to the Late Miocene period on the Mediterranean region, rather less attention has been paid to the Early and Middle Miocene. The purpose of this work is to investigate the palaeocirculation of the Mediterranean Sea and Paratethys during the different stages of closure. For this purpose we use of a regional ocean model and a Burdigalian (about 20 Ma) palaeogeographic map from the Peri-Tethys Atlas. In the interest of gaining insight into the first-order effects of the gateway evolution on marine circulation, different experiments, ranging from a deep gateway to a completely closed one, have been carried out. In addition, different sets of values for the atmospheric forcing have been applied in order to understand the role of the temperature and net evaporation on the marine circulation and the strait dynamics. The series of experiments allows us to analyze different scenarios, helping us to understand the evolution of such a complex system, and sheds a new light on the interpretation of the sedimentary record. Consequently, the information derived from this work can be useful for other studies focused on strait dynamics and could be a valid starting point for subsequent research on this gateway.

  19. Features of hydrocarbon distribution in the coastal zone of the northeastern Black Sea

    NASA Astrophysics Data System (ADS)

    Nemirovskaya, I. A.; Onegina, V. D.; Konovalov, B. V.

    2015-09-01

    Data on the content and composition of aliphatic and polycyclic aromatic hydrocarbons in surface water and bottom sediments are reported as compared to the distribution of total organic carbon, suspended particulate matter, lipids, and chlorophyll for the Greater Sochi area and the Gelendzhik and Blue bays. It is established that an influx of oil products leads to the increase of hydrocarbon concentrations in the water and bottom sediments, thus providing the present-day hydrocarbon background. Active transformation of organic matter in the water succession and on the water-bottom interface results in the prevalence of natural components in alkanes in spite of the high hydrocarbon concentrations (119-262 μg/g). The river-seawater mixing zone serves as a geochemical barrier preventing the influx of most pollutants delivered by rivers into open sea.

  20. Depositional and erosional features of the inner shelf, northeastern Bering Sea.

    USGS Publications Warehouse

    Hunter, R.E.; Thor, D.R.; Swisher, M.L.

    1981-01-01

    Sonographs and bathymetric profiles from water depths less than 15m in the Nome-Solomon, Port Clarence, and Yukon Delta areas of the Alaskan Bering Sea coast show features generated by waves, currents, and drifting ice. The surficial sediments in the Nome-Solomon and Port Clarence areas range in grain size from sand to boulder gravel and have many surface features visible on sonographs, whereas the sediments off the Yukon Delta are fine sands and silts that have few such features. Materials in the Nome-Solomon and Port Clarence areas have been seggregated by grain size into ribbons and irregular, elongate, and lobate patches. Coarse sand and fine gravel patches and ribbons are characterized by symmetrical ripples generated by storm waves. Ice-gouged furrows occur in all the nearshore areas studied.-from Authors

  1. Aquarius sea surface salinity in the South Indian Ocean: Revealing annual-period planetary waves

    NASA Astrophysics Data System (ADS)

    Menezes, Viviane V.; Vianna, Marcio L.; Phillips, Helen E.

    2014-06-01

    A new milestone has been reached with the launch of two dedicated satellite missions to routinely measure the sea surface salinity (SSS) fields from space at global and regional scales. In the present work, a thorough analysis of the first 2 years of Aquarius SSS data in the South Indian Ocean is performed. This analysis is focused on three questions: How accurate is Aquarius SSS related to in situ data from the fresh Indonesian Throughflow and salty subtropical waters? Can Aquarius give a spatial context for the data measured by the RAMA mooring system? Are westward propagating annual-period signals described in recent model simulations reproduced by Aquarius-derived SSS? We find Aquarius observations to be highly correlated with those of Argo floats, with small disagreements occurring near oceanic fronts. Aquarius gives fresher SSS than in situ data in the tropical region due to rainfall effects, except in the eastern basin where the freshening seems to be related to sharp localized leakages of very fresh waters from the Indonesian seas that the Aquarius product is not able to properly resolve. Aquarius data are shown to reproduce quite well the annual cycle obtained from RAMA and Argo gridded data sets. The annual cycle in Aquarius is characterized by SSS propagating features with different characteristics west and east of the Ninety East Ridge. These features are strikingly different from sea surface height waves. Our results suggest that SSS annual propagation might be reflecting coupled ocean-atmosphere dynamics and surface-subsurface processes operating over the entire South Indian Ocean.

  2. Written records of historical tsunamis in the northeastern South China Sea - challenges associated with developing a new integrated database

    NASA Astrophysics Data System (ADS)

    Lau, A. Y. A.; Switzer, A. D.; Dominey-Howes, D.; Aitchison, J. C.; Zong, Y.

    2010-09-01

    Comprehensive analysis of 15 previously published regional databases incorporating more than 100 sources leads to a newly revised historical tsunami database for the northeastern (NE) region of the South China Sea (SCS) including Taiwan. The validity of each reported historical tsunami event listed in our database is assessed by comparing and contrasting the information and descriptions provided in the other databases. All earlier databases suffer from errors associated with inaccuracies in translation between different languages, calendars and location names. The new database contains 205 records of "events" reported to have occurred between AD 1076 and 2009. We identify and investigate 58 recorded tsunami events in the region. The validity of each event is based on the consistency and accuracy of the reports along with the relative number of individual records for that event. Of the 58 events, 23 are regarded as "valid" (confirmed) events, three are "probable" events and six are "possible". Eighteen events are considered "doubtful" and eight events "invalid". The most destructive tsunami of the 23 valid events occurred in 1867 and affected Keelung, northern Taiwan, killing at least 100 people. Inaccuracies in the historical record aside, this new database highlights the occurrence and geographical extent of several large tsunamis in the NE SCS region and allows an elementary statistical analysis of annual recurrence intervals. Based on historical records from 1951-2009 the probability of a tsunami (from any source) affecting the region in any given year is relatively high (33.4%). However, the likelihood of a tsunami that has a wave height >1 m, and/or causes fatalities and damage to infrastructure occurring in the region in any given year is low (1-2%). This work indicates the need for further research using coastal stratigraphy and inundation modeling to help validate some of the historical accounts of tsunamis as well as adequately evaluate the recurrence

  3. ADCP-based Deep-water Current Velocity Structure and Suspended Sediment Distribution in the Northeastern South China Sea

    NASA Astrophysics Data System (ADS)

    Zhao, Y.; Liu, Z.; Zhang, Y.; Wang, W.; Li, J.; Xu, J.

    2013-12-01

    A downward-looking ADCP (acoustic doppler current profiler) was deployed in the northeastern South China Sea, near the Dongsha Islands, for 20 months (Sept. 2011 to Apr. 2013). The ADCP measures current velocity in the depth range of 1700-2100 m (0-400 m above seafloor). The relative backscatter coefficients (Sv) calculated from echo intensities of the ADCP are employed to estimate distribution patterns of suspended particles in the deep-water column of the region. The subtidal currents (PL33 low-pass filtered) in the depth range of 1700-2100 m generally flow southwestwards, with average speeds of 2-4 cm/s. However, bursts of strong currents with a speed as high as 11 cm/s throughout the observed water column (1700-2100 m) occurred several times during the 20-months period. These strong current events were in general followed by reversals of current directions (from southwestward to northeastward) whose recurrence interval appears to be in accordance with the length of strong current events. Elevated current speeds were also found in part, either upper or lower, of the observed water column, but these 'partial' events were usually not followed by a current reversal. During Mar. to Aug. 2012, a southwestward tongue-shaped high-velocity layer, which was probably linked to invasion of the North Pacific Deep Water, was observed in the depth range of 1750-2050 m, i.e. 50-350 m above seafloor, with the largest current velocity observed at ~200 m above seafloor. The Sv values were highest near the seafloor and decreased gradually upwards, forming pulse-like high sediment concentration events. Statistically, the high sediment-concentration events were related neither to the elevated current speed events nor to the current reversals.

  4. Monsoon variability in the northeastern Arabian Sea on orbital- and millennial scale during the past 200,000 years

    NASA Astrophysics Data System (ADS)

    Lückge, Andreas; Groeneveld, Jeroen; Steinke, Stephan; Mohtadi, Mahyar; Westerhold, Thomas; Schulz, Hartmut

    2016-04-01

    The Dansgaard-Oeschger oscillations and Heinrich events described in the Greenland ice cores and in North Atlantic and Western Mediterranean sediments are also expressed in the climate of the tropics, for example, as documented in Arabian Sea sediments. However, little is known about these fluctuations beyond the reach of the Greenland ice cores. Here, we present high-resolution geochemical, sedimentological as well as micropaleontological data from two cores (SO130-283KL, 987m water depth and SO130-289KL, 571m) off the coast of Pakistan, extending the monsoon record on orbital and millennial scales to the past 200,000 years. The stable oxygen isotope record of the surface-dwelling planktonic foraminifer G. ruber shows a strong correspondence to Greenland ice core δ18O, whereas the deepwater δ18O signal of benthic foraminifera (U. peregrina and G. affinis) reflects patterns recorded in ice cores from Antarctica. Strong shifts in benthic δ18O during stadials/Heinrich events are interpreted to show frequent advances of oxygen-rich intermediate water masses into the Arabian Sea originating from the southern ocean. Alkenone-derived SSTs varied between 23 and 28° C. Highest temperatures were encountered during interglacial MIS 5. Rapid SST changes of 2° C magnitude on millennial scale are overlain by long-term SST fluctuations. Interstadials (of glacial phases) and the cold phases of interglacials are characterized by sediments enriched in organic carbon (up to 4 % TOC) whereas sediments with low TOC contents (< 1 % TOC) appear during stadials and Heinrich events. Shifts at climate transitions, such as onsets of interstadials, were coeval with changes in productivity-related and anoxia-indicating proxies. Interstadial inorganic elemental data consistently show that enhanced fluxes of terrestrial-derived sediments are paralleled by productivity maxima, and are characterized by an increased fluvial contribution from the Indus River. In contrast, stadials are

  5. Interannual Sea Level Variations in the Tropical Indian Ocean from Geosat and Shallow Water Simulations

    NASA Technical Reports Server (NTRS)

    Perigaud, Claire; Delecluse, Pascale

    1993-01-01

    Sea level variations of the Indian Ocean north of 20 deg S are analyzed from Geosat satellite altimeter data over April 1985-September 1989. These variations are compared and interpreted with numerical simulations derived from a reduced gravity model forced by FSU observed winds over the same period. After decomposition into complex empirical orthogonal functions, the low-frequency anomalies are described by the first two modes for observations as well as for simulations. The sums of the two modes contain 34% and 40% of the observed and simulated variances, respectively. Averaged over the basin, the observed and simulated sea level changes are correlated by 0.92 over 1985-1988. The strongest change happens during the El Ninio 1986-1987: between winter 1986 and summer 1987 the basin-averaged sea level rises by approx. 1 cm. These low-frequency variations can partly be explained by changes in the Sverdrup circulation. The southern tropical Indian Ocean between 1O deg and 20 deg S is the domain where those changes are strongest: the averaged sea level rises by approx. 4.5 cm between winter 1986 and winter 1987. There, the signal propagates southwestward across the basin at a speed similar to free Rossby waves. Sensitivity of observed anomalies is examined over 1987-1988, with different orbit ephemeris, tropospheric corrections, and error reduction processes. The uncertainty of the basin-averaged sea level estimates is mostly due to the way the orbit error is reduced and reaches approx. 1 cm. Nonetheless, spatial correlation is good between the various observations and better than between observations and simulations. Sensitivity of simulated anomalies to the wind uncertainty, examined with Former Soviet Union (FSU) and European Center for Medium-Range Weather Forecasting (ECMWF) forcings over 1985-1988, shows that the variance of the simulations driven by ECMWF is 52% smaller, as FSU winds are stronger than ECMWF. Results show that the wind strength also affects the

  6. Underwater passive acoustic localization of Pacific walruses in the northeastern Chukchi Sea.

    PubMed

    Rideout, Brendan P; Dosso, Stan E; Hannay, David E

    2013-09-01

    This paper develops and applies a linearized Bayesian localization algorithm based on acoustic arrival times of marine mammal vocalizations at spatially-separated receivers which provides three-dimensional (3D) location estimates with rigorous uncertainty analysis. To properly account for uncertainty in receiver parameters (3D hydrophone locations and synchronization times) and environmental parameters (water depth and sound-speed correction), these quantities are treated as unknowns constrained by prior estimates and prior uncertainties. Unknown scaling factors on both the prior and arrival-time uncertainties are estimated by minimizing Akaike's Bayesian information criterion (a maximum entropy condition). Maximum a posteriori estimates for sound source locations and times, receiver parameters, and environmental parameters are calculated simultaneously using measurements of arrival times for direct and interface-reflected acoustic paths. Posterior uncertainties for all unknowns incorporate both arrival time and prior uncertainties. Monte Carlo simulation results demonstrate that, for the cases considered here, linearization errors are small and the lack of an accurate sound-speed profile does not cause significant biases in the estimated locations. A sequence of Pacific walrus vocalizations, recorded in the Chukchi Sea northwest of Alaska, is localized using this technique, yielding a track estimate and uncertainties with an estimated speed comparable to normal walrus swim speeds. PMID:23968051

  7. NEAMWave12: The First Tsunami Exercise in the North-eastern Atlantic, the Mediterranean and Connected Seas

    NASA Astrophysics Data System (ADS)

    Necmioglu, Ocal; Matias Matias, Luis; Schindelé, François; Behrens, Jörn; Tinti, Stefano; Chouliaras, Gerasimos; Melis, Nicos; Carrilho, Fernando; Santoro, Francesca; Rudloff, Alexander; Crochet, Emilie; Gonzalez, Mauricio

    2013-04-01

    The first tsunami exercise of the Tsunami Early Warning and Mitigation System in the North-eastern Atlantic, the Mediterranean and connected seas (NEAMTWS) has been conducted on 27-28 November 2012 involving 19 of the 39 member countries of the Intergovernmental Coordination Group (ICG) for NEAMTWS. NEAMWave12 involved the simulation of the assessment of a tsunami, based on an earthquake-driven scenario followed by alert message dissemination by Candidate Tsunami Watch Provider (CTWP) (Phase A) and continued with the simulation of the National Tsunami Warning Center's/Tsunami Warning Focal Point's (NTWC/TWFP) and Civil Protection Authoritie's (CPA) actions (Phase B), as soon as the message produced in Phase A has been received. There were four earthquake triggered tsunami scenarios in NEAMWave12 in different parts of the NEAM Region, where each CTWP (CENALT-France, NOA-Greece, IPMA-Portugal and KOERI-Turkey) was responsible for a single scenario. The CENALT Scenario was based on a plausible worst-case scenario of magnitude 7.5 along the Western Mediterranean Algerian margin at a fault located close to 21-22 August 1856 Jijel earthquakes. The NOA scenario was based on an earthquake similar to the well-known Amorgos earthquake, which was followed by a tsunami that devastated the Aegean Sea on 9 July 1956. The IPMA scenario was based on the 1 November 1755 Lisbon event with the assumption that the event represents the worst-case tsunami scenario impacting the NE Atlantic region. Finally, the KOERI scenario was based on a Mw=8.4 worst-case interpretation of the 8 August 1303 Crete and Dodecanese Islands earthquake resulting in destructive inundation in the Eastern Mediterranean. Initial evaluation of the exercise indicates that all CTWPs successfully participated in the exercise, where existing operational and some future prototype systems were utilized. System end-users (NTWC/TWFP/CPA) benefited from the exercise considerably, demonstrating the first successful test

  8. Evidence of Northeastern Atlantic Ocean Acidification Recorded by Boron Isotopes on Deep-sea Coral Madrepora oculata

    NASA Astrophysics Data System (ADS)

    Gonzalez-Roubaud, C.; Douville, E.; Bordier, L.; Louvat, P.; Gaillardet, J.; Hall-Spencer, J. M.; Juillet-Leclerc, A.

    2011-12-01

    Ocean acidification is caused by the rising levels of CO2 in the atmosphere since the industrial era. Seawater pH has already decreased 0.1 units in surface waters and will continue to drop as atmospheric CO2 levels increase. Assessing the pH variability during the last decades is essential as survival of calcifying organisms strongly depends on seawater pH. Several studies have shown the potential of boron isotopic composition in tropical corals for reconstructing for sea-surface paleo-pH at low latitudes. For highest latitudes and deeper waters (50-4500 m), cold-water corals are interesting and unique as natural archives not only because they live between 4°C and 12°C under strong currents, recording the parameters of sub-surface or intermediate currents, but also because they build their aragonite skeleton without the photosynthesis process. In order to assess if the seawater acidification has already reached the North Atlantic Ocean at high latitudes, pH reconstruction has been performed on a deep-sea coral Madrepora oculata sample from Rost Reef (67°N, 9°E, 350 m of depth). Boron isotopes have been measured on the Neptune Multi-Collector Inductively Coupled Plasma Mass Spectrometer (MCICP-MS) with direct injection system (d-DIHEN). External reproducibility obtained here for seawater reference NASS-2 was 0.1%. The model age estimates its life-span to 40±3 years (2σ) and the Li/Mg ratio estimates a relative constant seawater temperature during the whole period of growth of the coral (7.0±0.5°C). A drop tendency is observed on boron isotopes, reflecting a potential decrease of seawater pH of approximately 0.06±0.02 pH units during the last 40 years, depending on the isotopic fractionation coefficient employed for calculations. Similarly, seawater acidification rate is 0.0012±0.00015 pH units per year. pH and temperature reconstructions revealed an influence of thermohaline circulation and surface winds on the skeleton geochemistry. Supplementary

  9. Retreived bacteria from Noctiluca miliaris (green) bloom of the northeastern Arabian Sea

    NASA Astrophysics Data System (ADS)

    Basu, Subhajit; Matondkar, S. G. Prabhu; Furtado, Irene

    2013-01-01

    In recent years, seasonal blooms of the dinoflagellate Noctiluca miliaris have appeared in the open-waters of the northern Arabian Sea (NAS). This study provides the first characterization of bacteria from a seasonal bloom of green Noctiluca of NAS (20°N-17°N and 64°E-70°E), during the spring-inter-monsoon cruise of Sagar Sampada 253, in March 2007. Bacterial growth as assessed by most-probable number (MPN) and plate counts, revealed `variable-physiotypes' over a wide range of salinities (0%-25% w/v NaCl), pH levels (5-8.5), and organic nutrient strengths, in comparison to non-bloom waters. MPN indices of bacteria in surface waters of bloom stations *DWK and *PRB, corresponded to (3.08-4.41)×103 cells/mL at 3.5% NaCl (w/v), and (2.82-9.49)×102 cells/mL at 25% (w/v) NaCl in tryptone-yeast extract broth (TYE). Plate counts were (1.12-4)×106 CFU/mL at 0% (w/v) NaCl, (1.28-3.9)×106 CFU/mL at 3.5% (w/v) NaCl, and (0.4-7)×104 CFU/mL at 25% NaCl (w/v) on TYE. One-tenth-strength Zobell's gave (0.6-3.74)×105 CFU/mL at pH 5 to (3.58-7.5)×105 CFU/mL at pH 8.5. These bacteria were identified to the genera Bacillus, Cellulomonas, Staphylococcus, Planococcus, Dietzia, Virgibacillus, Micrococcus, Sporosarcinae, Leucobacter, and Halomonas. The identity of three strains (GUFBSS253N2, GUFBSS253N30, and GUFBSS253N84) was confirmed through 16S rDNA sequence homology as Bacillus cohnii, Bacillus flexus, and Bacillus cereus. The ˜2-3-fold higher plate counts of culturable bacteria from the open-waters of the NAS indicate that these bacteria could critically determine the biogeochemical dynamics of the bloom and its milieu. The role of these bacteria in sustaining/terminating the bloom is under evaluation.

  10. Gas hydrates in shallow deposits of the Amsterdam mud volcano, Anaximander Mountains, Northeastern Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Pape, Thomas; Kasten, Sabine; Zabel, Matthias; Bahr, André; Abegg, Friedrich; Hohnberg, Hans-Jürgen; Bohrmann, Gerhard

    2010-06-01

    We investigated gas hydrate in situ inventories as well as the composition and principal transport mechanisms of fluids expelled at the Amsterdam mud volcano (AMV; 2,025 m water depth) in the Eastern Mediterranean Sea. Pressure coring (the only technique preventing hydrates from decomposition during recovery) was used for the quantification of light hydrocarbons in near-surface deposits. The cores (up to 2.5 m in length) were retrieved with an autoclave piston corer, and served for analyses of gas quantities and compositions, and pore-water chemistry. For comparison, gravity cores from sites at the summit and beyond the AMV were analyzed. A prevalence of thermogenic light hydrocarbons was inferred from average C1/C2+ ratios <35 and δ13C-CH4 values of -50.6‰. Gas venting from the seafloor indicated methane oversaturation, and volumetric gas-sediment ratios of up to 17.0 in pressure cores taken from the center demonstrated hydrate presence at the time of sampling. Relative enrichments in ethane, propane, and iso-butane in gas released from pressure cores, and from an intact hydrate piece compared to venting gas suggest incipient crystallization of hydrate structure II (sII). Nonetheless, the co-existence of sI hydrate can not be excluded from our dataset. Hydrates fill up to 16.7% of pore volume within the sediment interval between the base of the sulfate zone and the maximum sampling depth at the summit. The concave-down shapes of pore-water concentration profiles recorded in the center indicate the influence of upward-directed advection of low-salinity fluids/fluidized mud. Furthermore, the SO{4/2-} and Ba2+ pore-water profiles in the central part of the AMV demonstrate that sulfate reduction driven by the anaerobic oxidation of methane is complete at depths between 30 cm and 70 cm below seafloor. Our results indicate that methane oversaturation, high hydrostatic pressure, and elevated pore-water activity caused by low salinity promote fixing of considerable

  11. Crustal features of the northeastern South China Sea: insights from seismic and magnetic interpretations

    NASA Astrophysics Data System (ADS)

    Yeh, Yi-Ching; Hsu, Shu-Kun; Doo, Wen-Bin; Sibuet, Jean-Claude; Liu, Char-Shine; Lee, Chao-Shing

    2012-12-01

    We interpret seven two-dimensional deep-penetration and long-offset multi-channel seismic profiles in the northernmost South China Sea area, which were collected by R/V Marcus G. Langseth during the TAIwan GEodynamics Research (TAIGER) project in 2009. To constrain the crustal characteristics, magnetic inversion and forward magnetic modeling were also performed. The seismic results clearly show tilted faulting blocks in the upper crust and most of the fault plane connects downward to a quasi-horizontal detachment as its bottom in the south of the Luzon-Ryukyu transform plate boundary. North of the plate boundary, a small-scale failed rifted basin (minimum 5 km in crustal thickness) with negative magnetization probably indicates an extended continental origin. Significant lower crustal material (LCM) was imaged under a crustal fracture area which indicated a continent and ocean transition origin. The thickest LCM (up to 6.5 km) is located at magnetic isochron C15 that is probably caused by the magma supply composite of a Miocene syn-rift volcanic event and Pliocene Dongsha volcanic activity for submarine volcanoes and sills in the surrounding area. The LCM also caused Miocene crustal blocks to be uplifted reversely as 17 km crustal thickness especially in the area of magnetic isochron C15 and C16. In addition, the wide fault blocks and LCM co-existed on the magnetic striped area (i.e. C15-C17) in the south of the Luzon-Ryukyu transform plate boundary. Magnetic forward modeling suggests that the whole thick crustal thickness (>12 km thick) needs to be magnetized in striped way as oceanic crust. However, the result also shows that the misfit between observed and synthetic magnetic anomaly is about 40 nT, north of isochron C16. The interval velocity derived from pre-stack time migration suggests that the crust is composed of basaltic intrusive upper crust and lower crustal material. The crustal nature should refer to a transition between continent and ocean. Thus, the

  12. On the recent seismic activity in North-Eastern Aegean Sea including the M(w)5.8 earthquake on 8 January 2013.

    PubMed

    Sarlis, Nicholas V

    2013-01-01

    In the last week of November 2012, we announced that a strong electrotelluric disturbance, which we judged to be a Seismic Electric Signal (SES) activity, was recorded at station Assiros located in Northern Greece. This disturbance was actually followed by an Mw5.8 earthquake on 8 January 2013 in North-Eastern Aegean Sea. Here we show that, by analyzing this SES activity and employing the natural time analysis of subsequent seismicity, we estimated the epicentral location, magnitude and occurrence time which are reasonably compatible with those of the Mw5.8 event. PMID:24213207

  13. On the recent seismic activity in North-Eastern Aegean Sea including the Mw5.8 earthquake on 8 January 2013

    PubMed Central

    SARLIS, Nicholas V.

    2013-01-01

    In the last week of November 2012, we announced that a strong electrotelluric disturbance, which we judged to be a Seismic Electric Signal (SES) activity, was recorded at station Assiros located in Northern Greece. This disturbance was actually followed by an Mw5.8 earthquake on 8 January 2013 in North-Eastern Aegean Sea. Here we show that, by analyzing this SES activity and employing the natural time analysis of subsequent seismicity, we estimated the epicentral location, magnitude and occurrence time which are reasonably compatible with those of the Mw5.8 event. PMID:24213207

  14. A ~25 ka Indian Ocean monsoon variability record from the Andaman Sea

    USGS Publications Warehouse

    Rashid, H.; Flower, B.P.; Poore, R.Z.; Quinn, T.M.

    2007-01-01

    Recent paleoclimatic work on terrestrial and marine deposits from Asia and the Indian Ocean has indicated abrupt changes in the strength of the Asian monsoon during the last deglaciation. Comparison of marine paleoclimate records that track salinity changes from Asian rivers can help evaluate the coherence of the Indian Ocean monsoon (IOM) with the larger Asian monsoon. Here we present paired Mg/Ca and δ18O data on the planktic foraminifer Globigerinoides ruber (white) from Andaman Sea core RC12-344 that provide records of sea-surface temperature (SST) and δ18O of seawater (δ18Osw) over the past 25,000 years (ka) before present (BP). Age control is based on nine accelerator mass spectrometry (AMS) dates on mixed planktic foraminifera. Mg/Ca-SST data indicate that SST was ∼3 °C cooler during the last glacial maximum (LGM) than the late Holocene. Andaman Sea δ18Osw exhibited higher than present values during the Lateglacial interval ca 19–15 ka BP and briefly during the Younger Dryas ca 12 ka BP. Lower than present δ18Osw values during the BØlling/AllerØd ca 14.5–12.6 ka BP and during the early Holocene ca 10.8–5.5 ka BP are interpreted to indicate lower salinity, reflect some combination of decreased evaporation–precipitation (E–P) over the Andaman Sea and increased Irrawaddy River outflow. Our results are consistent with the suggestion that IOM intensity was stronger than present during the BØlling/AllerØd and early Holocene, and weaker during the late glaciation, Younger Dryas, and the late Holocene. These findings support the hypothesis that rapid climate change during the last deglaciation and Holocene included substantial hydrologic changes in the IOM system that were coherent with the larger Asian monsoon.

  15. Evolution and sub-surface characteristics of a sea-surface temperature filament and front in the northeastern Arabian Sea during November-December 2012

    NASA Astrophysics Data System (ADS)

    Vipin, P.; Sarkar, Kankan; Aparna, S. G.; Shankar, D.; Sarma, V. V. S. S.; Gracias, D. G.; Krishna, M. S.; Srikanth, G.; Mandal, R.; Rama Rao, E. P.; Srinivasa Rao, N.

    2015-10-01

    We used satellite-derived sea-surface-temperature (SST) data along with in-situ data collected along a meridional transect between 18.85 and 20.25°N along 69.2°E to describe the evolution of an SST filament and front during 25 November to 1 December in the northeastern Arabian Sea (NEAS). Both features were ~ 100 km long, lasted about a week, and were associated with weak temperature gradients (~ 0.07 °C km- 1). The in-situ data were collected first using a suite of surface sensors during a north-south mapping of this transect and showed the existence of a chlorophyll maximum within the filament. This surface data acquisition was followed by a high-resolution south-north CTD (conductivity-temperature-depth) sampling along the transect. In the two days that elapsed between the two in-situ measurements, the filament had shrunk in size and moved northward. In general, the current direction was northwestward and advected these mesoscale features. The CTD data also showed an SST front towards the northern end of the transect. In both these features, the chlorophyll concentration was higher than in the surrounding waters. The temperature and salinity data from the CTD suggest upward mixing or pumping of water from the base of the mixed layer, where a chlorophyll maximum was present, into the mixed layer that was about 60 m thick. A striking diurnal cycle was evident in the chlorophyll concentration, with higher values tending to occur closer to the surface during the night. The in-situ data from both surface sensors and CTD, and so also satellite-derived chlorophyll data, showed higher chlorophyll concentration, particularly at sub-surface levels, between the filament and the front, but there was no corresponding signature in the temperature and salinity data. Analysis of the SST fronts in the satellite data shows that fronts weaker than those associated with the filament and the front had crossed the transect in this region a day or two preceding the sampling of the

  16. Predicting East African spring droughts using Pacific and Indian Ocean sea surface temperature indices

    NASA Astrophysics Data System (ADS)

    Funk, C.; Hoell, A.; Shukla, S.; Bladé, I.; Liebmann, B.; Roberts, J. B.; Robertson, F. R.; Husak, G.

    2014-12-01

    In eastern East Africa (the southern Ethiopia, eastern Kenya and southern Somalia region), poor boreal spring (long wet season) rains in 1999, 2000, 2004, 2007, 2008, 2009, and 2011 contributed to severe food insecurity and high levels of malnutrition. Predicting rainfall deficits in this region on seasonal and decadal time frames can help decision makers implement disaster risk reduction measures while guiding climate-smart adaptation and agricultural development. Building on recent research that links more frequent East African droughts to a stronger Walker circulation, resulting from warming in the Indo-Pacific warm pool and an increased east-to-west sea surface temperature (SST) gradient in the western Pacific, we show that the two dominant modes of East African boreal spring rainfall variability are tied to SST fluctuations in the western central Pacific and central Indian Ocean, respectively. Variations in these two rainfall modes can thus be predicted using two SST indices - the western Pacific gradient (WPG) and central Indian Ocean index (CIO), with our statistical forecasts exhibiting reasonable cross-validated skill (rcv ≈ 0.6). In contrast, the current generation of coupled forecast models show no skill during the long rains. Our SST indices also appear to capture most of the major recent drought events such as 2000, 2009 and 2011. Predictions based on these simple indices can be used to support regional forecasting efforts and land surface data assimilations to help inform early warning and guide climate outlooks.

  17. Predicting East African spring droughts using Pacific and Indian Ocean sea surface temperature indices

    NASA Astrophysics Data System (ADS)

    Funk, C.; Hoell, A.; Shukla, S.; Bladé, I.; Liebmann, B.; Roberts, J. B.; Robertson, F. R.; Husak, G.

    2014-03-01

    In southern Ethiopia, Eastern Kenya, and southern Somalia, poor boreal spring rains in 1999, 2000, 2004, 2007, 2008, 2009, and 2011 contributed to severe food insecurity and high levels of malnutrition. Predicting rainfall deficits in this region on seasonal and decadal time frames can help decision makers implement disaster risk reduction measures while guiding climate-smart adaptation and agricultural development. Building on recent research that links more frequent droughts in that region to a stronger Walker Circulation, warming in the Indo-Pacific warm pool, and an increased western Pacific sea surface temperature (SST) gradient, we show that the two dominant modes of East African boreal spring rainfall variability are tied, respectively, to western-central Pacific and central Indian Ocean SST. Variations in these rainfall modes can be predicted using two previously defined SST indices - the West Pacific Gradient (WPG) and Central Indian Ocean index (CIO), with the WPG and CIO being used, respectively, to predict the first and second rainfall modes. These simple indices can be used in concert with more sophisticated coupled modeling systems and land surface data assimilations to help inform early warning and guide climate outlooks.

  18. Intraseasonal Variability of the Equatorial Indian Ocean Observed from Sea Surface Height, Wind, and Temperature Data

    NASA Technical Reports Server (NTRS)

    Fu, Lee-Lueng

    2007-01-01

    The forcing of the equatorial Indian Ocean by the highly periodic monsoon wind cycle creates many interesting intraseasonal variabilities. The frequency spectrum of the wind stress observations from the European Remote Sensing Satellite scatterometers reveals peaks at the seasonal cycle and its higher harmonics at 180, 120, 90, and 75 days. The observations of sea surface height (SSH) from the Jason and Ocean Topography Experiment (TOPEX)/Poseidon radar altimeters are analyzed to study the ocean's response. The focus of the study is on the intraseasonal periods shorter than the annual period. The semiannual SSH variability is characterized by a basin mode involving Rossby waves and Kelvin waves traveling back and forth in the equatorial Indian Ocean between 10(deg)S and 10(deg)N. However, the interference of these waves with each other masks the appearance of individual Kelvin and Rossby waves, leading to a nodal point (amphidrome) of phase propagation on the equator at the center of the basin. The characteristics of the mode correspond to a resonance of the basin according to theoretical models. The theory also calls for similar modes at 90 and 60 days.

  19. Fate of copper complexes in hydrothermally altered deep-sea sediments from the Central Indian Ocean Basin.

    PubMed

    Chakraborty, Parthasarathi; Sander, Sylvia G; Jayachandran, Saranya; Nath, B Nagender; Nagaraju, G; Chennuri, Kartheek; Vudamala, Krushna; Lathika, N; Mascarenhas-Pereira, Maria Brenda L

    2014-11-01

    The current study aims to understand the speciation and fate of Cu complexes in hydrothermally altered sediments from the Central Indian Ocean Basin and assess the probable impacts of deep-sea mining on speciation of Cu complexes and assess the Cu flux from this sediment to the water column in this area. This study suggests that most of the Cu was strongly associated with different binding sites in Fe-oxide phases of the hydrothermally altered sediments with stabilities higher than that of Cu-EDTA complexes. The speciation of Cu indicates that hydrothermally influenced deep-sea sediments from Central Indian Ocean Basin may not significantly contribute to the global Cu flux. However, increasing lability of Cu-sediment complexes with increasing depth of sediment may increase bioavailability and Cu flux to the global ocean during deep-sea mining. PMID:25108489

  20. Model study of the circulation of the Miocene Mediterranean Sea and Paratethys: closure of the Indian Gateway

    NASA Astrophysics Data System (ADS)

    de la Vara, A.; Meijer, P. Th.; Wortel, M. J. R.

    2013-08-01

    The early Mediterranean Sea and the Paratethys were both connected to the Indian Ocean until the Early/Middle Miocene, when the convergence of the Eurasian and African-Arabian plates caused the constriction and final closure of the Indian Gateway. Although little is certain concerning the timing of the closure and the consequences that it entailed, it is broadly accepted that it had a large effect on water properties and ocean dynamics on the regional and global scales and, in that way, may have also played a role in the evolution of climate. The purpose of this work is to investigate the palaeocirculation of the Mediterranean Sea and the Paratethys during different stages of closure and the impact of this event on the water exchange between the Mediterranean and the adjacent Indian and Atlantic oceans. To this extent we use a regional ocean model and an Early Miocene palaeogeographic map. In addition to varying the depth of the Indian Gateway, different sets of values for the atmospheric forcing have been applied in order to check the robustness of our results and to understand the role of the temperature and net evaporation on the marine circulation and the strait dynamics. The series of experiments performed shows that, with an Indian Gateway ranging from 1000 to 460 m deep, the Mediterranean accommodates anti-estuarine exchange to the Indian and Atlantic oceans. The shoaling of the Indian Gateway results in a progressive decrease in the water exchanged between the Indian Ocean and the Mediterranean basin, and increases the spatial extension of the Atlantic inflow. When the gateway is as shallow as 220 m, there is no effective water exchange between the Indian Ocean and the Mediterranean basin, suggesting that the gateway may have been closed in an oceanographical sense, even while a water passage was still in existence. On a basinal scale, closure results in a rearrangement of the circulation pattern which leads to changes in salinity and temperature in both

  1. 75 FR 7435 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-19

    ... United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic Deep-Sea Red Crab Specifications... Atlantic deep-sea red crab fishery, including a target total allowable catch (TAC) and a fleet-wide days-at-sea (DAS) allocation. The implementing regulations for the Atlantic Deep-Sea Red Crab...

  2. Importance and origin of halosteric contribution to sea level change in the southeast Indian Ocean during 2005-2013

    NASA Astrophysics Data System (ADS)

    Llovel, William; Lee, Tong

    2015-02-01

    Steric sea level change has been identified as one of the major contributors to the regional variability of sea level trends observed by satellite altimetry for the past two decades. This contribution varies in space and time. The temperature (thermosteric) contribution to sea level has generally been found to be more important than the salinity (halosteric) effect. Based on sea level measurements from satellite altimetry and temperature and salinity data from Argo floats during 2005-2013, we found that the southeast Indian Ocean experiences a large halosteric contribution to sea level change. The conspicuously large halosteric contribution is associated with a freshening in the upper 300 m. Neither local atmospheric forcing such as Ekman pumping and E - P nor halosteric signal transmitted from the western tropical Pacific can explain this freshening. An enhanced precipitation in the Maritime Continent region and the observed strengthening of the Indonesian throughflow are the likely causes.

  3. Regal phylogeography: Range-wide survey of the marine angelfish Pygoplites diacanthus reveals evolutionary partitions between the Red Sea, Indian Ocean, and Pacific Ocean.

    PubMed

    Coleman, Richard R; Eble, Jeffrey A; DiBattista, Joseph D; Rocha, Luiz A; Randall, John E; Berumen, Michael L; Bowen, Brian W

    2016-07-01

    The regal angelfish (Pygoplites diacanthus; family Pomacanthidae) occurs on reefs from the Red Sea to the central Pacific, with an Indian Ocean/Rea Sea color morph distinct from a Pacific Ocean morph. To assess population differentiation and evaluate the possibility of cryptic evolutionary partitions in this monotypic genus, we surveyed mtDNA cytochrome b and two nuclear introns (S7 and RAG2) in 547 individuals from 15 locations. Phylogeographic analyses revealed four mtDNA lineages (d=0.006-0.015) corresponding to the Pacific Ocean, the Red Sea, and two admixed lineages in the Indian Ocean, a pattern consistent with known biogeographic barriers. Christmas Island in the eastern Indian Ocean had both Indian and Pacific lineages. Both S7 and RAG2 showed strong population-level differentiation between the Red Sea, Indian Ocean, and Pacific Ocean (ΦST=0.066-0.512). The only consistent population sub-structure within these three regions was at the Society Islands (French Polynesia), where surrounding oceanographic conditions may reinforce isolation. Coalescence analyses indicate the Pacific (1.7Ma) as the oldest extant lineage followed by the Red Sea lineage (1.4Ma). Results from a median-joining network suggest radiations of two lineages from the Red Sea that currently occupy the Indian Ocean (0.7-0.9Ma). Persistence of a Red Sea lineage through Pleistocene glacial cycles suggests a long-term refuge in this region. The affiliation of Pacific and Red Sea populations, apparent in cytochrome b and S7 (but equivocal in RAG2) raises the hypothesis that the Indian Ocean was recolonized from the Red Sea, possibly more than once. Assessing the genetic architecture of this widespread monotypic genus reveals cryptic evolutionary diversity that merits subspecific recognition. We recommend P.d. diacanthus and P.d. flavescens for the Pacific and Indian Ocean/Red Sea forms. PMID:27068838

  4. The Footprint of the Inter-decadal Pacific Oscillation in Indian Ocean Sea Surface Temperatures

    NASA Astrophysics Data System (ADS)

    Dong, Lu; Zhou, Tianjun; Dai, Aiguo; Song, Fengfei; Wu, Bo; Chen, Xiaolong

    2016-02-01

    Superimposed on a pronounced warming trend, the Indian Ocean (IO) sea surface temperatures (SSTs) also show considerable decadal variations that can cause regional climate oscillations around the IO. However, the mechanisms of the IO decadal variability remain unclear. Here we perform numerical experiments using a state-of-the-art, fully coupled climate model in which the external forcings with or without the observed SSTs in the tropical eastern Pacific Ocean (TEP) are applied for 1871-2012. Both the observed timing and magnitude of the IO decadal variations are well reproduced in those experiments with the TEP SSTs prescribed to observations. Although the external forcings account for most of the warming trend, the decadal variability in IO SSTs is dominated by internal variability that is induced by the TEP SSTs, especially the Inter-decadal Pacific Oscillation (IPO). The IPO weakens (enhances) the warming of the external forcings by about 50% over the IO during IPO’s cold (warm) phase, which contributes about 10% to the recent global warming hiatus since 1999. The decadal variability in IO SSTs is modulated by the IPO-induced atmospheric adjustment through changing surface heat fluxes, sea surface height and thermocline depth.

  5. The Footprint of the Inter-decadal Pacific Oscillation in Indian Ocean Sea Surface Temperatures.

    PubMed

    Dong, Lu; Zhou, Tianjun; Dai, Aiguo; Song, Fengfei; Wu, Bo; Chen, Xiaolong

    2016-01-01

    Superimposed on a pronounced warming trend, the Indian Ocean (IO) sea surface temperatures (SSTs) also show considerable decadal variations that can cause regional climate oscillations around the IO. However, the mechanisms of the IO decadal variability remain unclear. Here we perform numerical experiments using a state-of-the-art, fully coupled climate model in which the external forcings with or without the observed SSTs in the tropical eastern Pacific Ocean (TEP) are applied for 1871-2012. Both the observed timing and magnitude of the IO decadal variations are well reproduced in those experiments with the TEP SSTs prescribed to observations. Although the external forcings account for most of the warming trend, the decadal variability in IO SSTs is dominated by internal variability that is induced by the TEP SSTs, especially the Inter-decadal Pacific Oscillation (IPO). The IPO weakens (enhances) the warming of the external forcings by about 50% over the IO during IPO's cold (warm) phase, which contributes about 10% to the recent global warming hiatus since 1999. The decadal variability in IO SSTs is modulated by the IPO-induced atmospheric adjustment through changing surface heat fluxes, sea surface height and thermocline depth. PMID:26884089

  6. The Footprint of the Inter-decadal Pacific Oscillation in Indian Ocean Sea Surface Temperatures

    PubMed Central

    Dong, Lu; Zhou, Tianjun; Dai, Aiguo; Song, Fengfei; Wu, Bo; Chen, Xiaolong

    2016-01-01

    Superimposed on a pronounced warming trend, the Indian Ocean (IO) sea surface temperatures (SSTs) also show considerable decadal variations that can cause regional climate oscillations around the IO. However, the mechanisms of the IO decadal variability remain unclear. Here we perform numerical experiments using a state-of-the-art, fully coupled climate model in which the external forcings with or without the observed SSTs in the tropical eastern Pacific Ocean (TEP) are applied for 1871–2012. Both the observed timing and magnitude of the IO decadal variations are well reproduced in those experiments with the TEP SSTs prescribed to observations. Although the external forcings account for most of the warming trend, the decadal variability in IO SSTs is dominated by internal variability that is induced by the TEP SSTs, especially the Inter-decadal Pacific Oscillation (IPO). The IPO weakens (enhances) the warming of the external forcings by about 50% over the IO during IPO’s cold (warm) phase, which contributes about 10% to the recent global warming hiatus since 1999. The decadal variability in IO SSTs is modulated by the IPO-induced atmospheric adjustment through changing surface heat fluxes, sea surface height and thermocline depth. PMID:26884089

  7. The footprint of the inter-decadal Pacific oscillation in Indian Ocean sea surface temperatures

    DOE PAGESBeta

    Dong, Lu; Zhou, Tianjun; Dai, Aiguo; Song, Fengfei; Wu, Bo; Chen, Xiaolong

    2016-02-17

    Superimposed on a pronounced warming trend, the Indian Ocean (IO) sea surface temperatures (SSTs) also show considerable decadal variations that can cause regional climate oscillations around the IO. However, the mechanisms of the IO decadal variability remain unclear. Here we perform numerical experiments using a state-of-the-art, fully coupled climate model in which the external forcings with or without the observed SSTs in the tropical eastern Pacific Ocean (TEP) are applied for 1871–2012. Both the observed timing and magnitude of the IO decadal variations are well reproduced in those experiments with the TEP SSTs prescribed to observations. Although the external forcingsmore » account for most of the warming trend, the decadal variability in IO SSTs is dominated by internal variability that is induced by the TEP SSTs, especially the Inter-decadal Pacific Oscillation (IPO). The IPO weakens (enhances) the warming of the external forcings by about 50% over the IO during IPO’s cold (warm) phase, which contributes about 10% to the recent global warming hiatus since 1999. As a result, the decadal variability in IO SSTs is modulated by the IPO-induced atmospheric adjustment through changing surface heat fluxes, sea surface height and thermocline depth.« less

  8. The contribution of inertial oscillations in water dynamics in terms of the 2013/03/24 storm situation in the northeastern part of the Black and Azov Seas

    NASA Astrophysics Data System (ADS)

    Diansky, Nikolay; Gusev, Anatoly; Vladimir, Fomin; Kabatchenko, Ilya; Evgeny, Borisov

    2015-04-01

    The results of sea dynamics numerical simulation for the northeastern part of the Black Sea and Azov (BAS) are manifested for period of strong storm occured on 22 - 28 March 2013. The INMOM (Institute Numerical Mathematics Ocean Model) was used, implemented for the whole BAS domain with a spatial resolution about 4 km. This INMOM version is the main component of the system for operational diagnosis and prognosis of hydrometeorological characteristics in the BAS implemented in the State Oceanography Institute (SOI). This system also includes Weather Research and Forecasting (WRF) model for computation of atmospheric forcing and Russian wind wave model (RWWM) for computation of the wind wave characteristics. During the storm, the extensive cyclone appeared with the center located northward to the Sea of Azov. Its southern periphery, covering almost the whole BS, formed airflow, which lead to the domination of the southeast wind in the eastern part of the BS with speed more than 20 m/s over the open sea. At the same time, the strong wind intensification occurred on the night of 2013/03/23. It lead to the excitement of inertial oscillations in the wind influence zone with sea velocities up to 100-120 cm/s. The simulations of the wind wave height, performed for this period using RWWM, revealed strong wind wave intensification with heights over 6 m. This was the main factor that led to the destruction of coast-protecting structures in the area Imeretinsky coast. At the same time, the sea level was not greater than 20 cm, which is nevertheless also led to the destruction of coast-protecting structures. The oscillation period of sea velocity in the active layer corresponds to the Coriolis frequency. The field of velocity inertial oscillation covered the whole open eastern part of the BS. Following the physical nature of inertial oscillations, a few hours after the storm beginning, the sea velocity field in the 0-30m layer stopped corresponding to the storm wind, and

  9. Foraminiferal record of anthropogenic environmental changes in the northeastern Adriatic Sea (Panzano Bay, Gulf of Trieste, Italy)

    NASA Astrophysics Data System (ADS)

    Vidovic, Jelena; Cosovic, Vlasta; Kern, Vieana; Gallmetzer, Ivo; Haselmair, Alexandra; Zuschin, Martin

    2016-04-01

    The northern Adriatic Sea is one of the world's largest modern epicontinental seas and a young marine ecosystem that has been subject to various natural and anthropogenic processes during the Holocene: marine transgression, regional climate fluctuations, urbanisation and pollution. The Gulf of Trieste, located in the northeastern part, presents the area of particular interest, as it is a shallow and sheltered embayment, prone to the accumulation of pollutants, populated for at least the last 2000 years and with recent anthropogenic pressure coming from several rivers, ports and industrial zones. The aim of this multidisciplinary study is to provide a high-resolution record of these processes using benthic foraminiferal assemblages, geochemical proxies (trace metals, nutrients and pollutants), sedimentological (sedimentation rates) and time-averaging data (from dated mollusc shells). One core of 1.5 m length was taken at the sampling station Panzano Bay, northernmost part of the Gulf of Trieste, at the water depth of 12.5 m. The sedimentation rate is estimated to be 2.5 mm/year, based on 210Pb sediment dating, while dating of the molluscs shells revealed the age at the bottom of the core to be approximately 500 years. The core was sliced into smaller subsamples, and four sediment fractions of each subsample (63, 125, 250 and 500 μm) were analysed for standard properties of the foraminiferal community (faunal composition, absolute and relative abundances of species, biodiversity indices), in order to make comparison with relevant physical and geochemical properties of the sediment. The results concerning changes in foraminiferal species composition, their abundance and biodiversity, supported by statistical analyses (cluster analysis, NMDS, PCA), allow identification of three major foraminiferal associations: 1) 80-150 cm - the oldest association is dominated by opportunistic genera ans species, characteristic for unstable environments: Valvulineria sp. (25

  10. Last Glacial to Holocene history of the Indian Monsoon recorded in Andaman Sea sediments

    NASA Astrophysics Data System (ADS)

    Hathorne, E. C.; Yirgaw, D. G.; Ali, S.; Giosan, L.; Collett, T. S.; Nath, B.; Frank, M.

    2013-12-01

    Over 3 billion people live in the area influenced by the Asian monsoon, the rains of which provide vital water resources while posing a risk to human life through flooding. Despite the importance to so many the monsoon is difficult to predict and model, making its future development in a changing global climate uncertain. To help improve models and predictions, histories of monsoon variability beyond the instrumental record are required. The past variability of the Indian Monsoon is mostly known from records of monsoon wind strength over the Arabian Sea. This study uses a unique long sediment core obtained by the drill ship JOIDES Resolution in the Andaman Sea to examine the past variability of Indian Monsoon precipitation on the Indian sub-continent and directly over the ocean. Here we present multi-proxy data examining variations during the last glacial and deglaciation. The radiogenic Sr, Nd, and Pb isotopic composition of the clay fraction (<2 microns) indicates that the Irrawaddy river has been the dominant source of fine detrital material to the site for the last 60 kyrs. The Nd and Pb isotope results show negligible variability indicating little change of the eroded source rocks supplying material and suggest a spatial stability of the monsoon in the Irrawaddy catchment. The clay minerology is dominated by smectite reflecting overall intense chemical weathering. Decreases of smectite/(illite + chlorite) are associated with the Heinrich events suggesting less intense weathering. An increase of the smectite/(illite + chlorite) and the radiogenic Sr isotope composition of the clays during the deglaciation indicates an increase in weathering intensity. The monsoon related influx of freshwater to the Bay of Bengal and Andaman Sea leads to a low salinity surface layer and a strong stratification of the upper 200 meters. Ocean atlas data (Antonov et al., 2010) indicate that this stratification is remarkably stable throughout the year while the salinity of the

  11. Effects of the interannual variability in chlorophyll concentrations on sea surface temperatures in the east tropical Indian Ocean

    NASA Astrophysics Data System (ADS)

    Ma, Jinfeng; Liu, Hailong; Lin, Pengfei; Zhan, Haigang

    2015-10-01

    The effects of interannual variability in chlorophyll concentrations on sea surface temperatures in the east tropical Indian Ocean (ETIO) during two positive Indian Ocean Dipole (IOD) events (in the boreal fall of 1997 and 2006) are investigated; this is done through two ocean model experiments, one with and one without the interannual variability of chlorophyll concentrations. A comparison of the two chlorophyll perturbation experiments reveals that, in contrast to the cooling effects at the seasonal time scale, increased chlorophyll concentrations during positive IOD events lead to an increase in the sea surface temperatures within the ETIO. Although upward velocity is enhanced (with a cooling effect), this does not counterbalance the increase in solar heating caused by the increased chlorophyll concentrations. This interannual variability of chlorophyll concentrations in the ETIO could reduce the amplitude of the IOD by about 6%.

  12. Annual sea level variations in the southern tropical Indian Ocean from Geosat and shallow-water simulations

    NASA Technical Reports Server (NTRS)

    Perigaud, Claire; Delecluse, Pascale

    1992-01-01

    Sea level variations in the Indian Ocean north of 20 deg S are analyzed from Geosat satellite altimeter data in 1987-1988. These observed variations are compared with numerical simulations from a reduced-gravity model forced by observed winds over the same period. The first complex empirical orthogonal function of observed and simulated variations is an annual signal. For this signal, observations and simulations are highly correlated in both time and space. Off-equatorial sea level variations propagate westward and poleward as Rossby waves. The strongest annual variations occur in the southeastern tropical Indian Ocean. The maximum amplitude (about 12 cm) is located at about 90 deg E, 12 deg S, although the wind stress curl is weak there and east of it. The signal propagates from the eastern boundary to the southwest across almost all the basin.

  13. A new genus and species of deep-sea glass sponge (Porifera, Hexactinellida, Aulocalycidae) from the Indian Ocean.

    PubMed

    Sautya, Sabyasachi; Tabachnick, Konstantin R; Ingole, Baban

    2011-01-01

    New hexactinellid sponges were collected from 2589 m depth on the Carlsberg Ridge in the Indian Ocean during deep-sea dredging. All fragments belong to a new genus and species, Indiellagen. n.ridgenensissp. n., a representative of the family Aulocalycidae described here. The peculiar features of this sponge, not described earlier for other Aulocalycidae, are: longitudinal strands present in several layers and epirhyses channelization. PMID:22140345

  14. A new genus and species of deep-sea glass sponge (Porifera, Hexactinellida, Aulocalycidae) from the Indian Ocean

    PubMed Central

    Sautya, Sabyasachi; Tabachnick, Konstantin R.; Ingole, Baban

    2011-01-01

    Abstract New hexactinellid sponges were collected from 2589 m depth on the Carlsberg Ridge in the Indian Ocean during deep-sea dredging. All fragments belong to a new genus and species, Indiella gen. n. ridgenensis sp. n., a representative of the family Aulocalycidae described here. The peculiar features of this sponge, not described earlier for other Aulocalycidae, are: longitudinal strands present in several layers and epirhyses channelization. PMID:22140345

  15. 76 FR 36511 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab; Amendment 3

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-22

    ... United States; Atlantic Deep-Sea Red Crab; Amendment 3 AGENCY: National Marine Fisheries Service (NMFS... Fishery Management Council (Council) has submitted Amendment 3 to the Atlantic Deep-Sea Red Crab...

  16. An assessment of Indian monsoon seasonal forecasts and mechanisms underlying monsoon interannual variability in the Met Office GloSea5-GC2 system

    NASA Astrophysics Data System (ADS)

    Johnson, Stephanie J.; Turner, Andrew; Woolnough, Steven; Martin, Gill; MacLachlan, Craig

    2016-06-01

    We assess Indian summer monsoon seasonal forecasts in GloSea5-GC2, the Met Office fully coupled subseasonal to seasonal ensemble forecasting system. Using several metrics, GloSea5-GC2 shows similar skill to other state-of-the-art seasonal forecast systems. The prediction skill of the large-scale South Asian monsoon circulation is higher than that of Indian monsoon rainfall. Using multiple linear regression analysis we evaluate relationships between Indian monsoon rainfall and five possible drivers of monsoon interannual variability. Over the time period studied (1992-2011), the El Niño-Southern Oscillation (ENSO) and the Indian Ocean dipole (IOD) are the most important of these drivers in both observations and GloSea5-GC2. Our analysis indicates that ENSO and its teleconnection with Indian rainfall are well represented in GloSea5-GC2. However, the relationship between the IOD and Indian rainfall anomalies is too weak in GloSea5-GC2, which may be limiting the prediction skill of the local monsoon circulation and Indian rainfall. We show that this weak relationship likely results from a coupled mean state bias that limits the impact of anomalous wind forcing on SST variability, resulting in erroneous IOD SST anomalies. Known difficulties in representing convective precipitation over India may also play a role. Since Indian rainfall responds weakly to the IOD, it responds more consistently to ENSO than in observations. Our assessment identifies specific coupled biases that are likely limiting GloSea5-GC2 Indian summer monsoon seasonal prediction skill, providing targets for model improvement.

  17. Chelidoperca stella, a new species of perchlet (Perciformes: Serranidae) from the Andaman Sea, eastern Indian Ocean.

    PubMed

    Matsunuma, Mizuki; Motomura, Hiroyuki

    2016-01-01

    A new species of serranid fish, Chelidoperca stella, is described on the basis of five specimens from the Andaman Sea in the eastern Indian Ocean. The species can be readily distinguished from all valid congeners by having fewer pored lateral-line scales (34 or 35 vs. 40-45 in the latter) and the pelvic fin white with several small yellow spots (vs. spots absent). The species is also characterized by having relatively high counts of small serrae on the posterior margins of the preopercle (33-43 serrae), interopercle (7-10) and subopercle (18-28), despite the small body size (51.7-61.8 mm SL). Although Chelidoperca stella resembles C. margaritifera in having 2.5 scale rows between lateral line and the sixth dorsal-fin spine base, a relatively wider interorbital region, and the interorbital scales not reaching a vertical through the orbit anterior margin, but differs by having the above-mentioned diagnostic characters plus a slightly shorter longest anal-fin soft ray [17.4-18.7 (mean 18.1) % SL vs. 22.6-26.4 (24.4) % SL in C. margaritifera]. PMID:27394461

  18. A review of recent evaluation of satellite estimates sea surface salinity in the tropical Indian Ocean

    NASA Astrophysics Data System (ADS)

    Momin, Imranali M.; Mitra, Ashis K.; Mahapatra, D. K.; Rajagopal, E. N.

    2016-05-01

    Aquarius is mission that aims to measure Sea surface salinity (SSS) from the space in order to provide the global salinity for climate studies. Accurate estimation of SSS is useful for the hydrological cycle, oceanographic processes, and climate. Recently the new version (V4) of Aquarius data releases with the improving the quality of the data and achieving the mission accuracy requirement globally on monthly scale. This paper highlight the results of recently release Aquarius V4, and version 3 (V3) data with Argo observations on monthly time scale from 2012-2014 periods. The spatial distribution of mean SSS shows that both products capture the SSS variation very well. The Aquarius V4 SSS showed minor improvement over the Aquarius V3 SSS with less root mean square error over the central & eastern equatorial Indian Ocean (EEIO) & part of Bay of Bengal (BOB). The frequency distribution is also improved in Aquarius V4 compare to Aquarius V3 average over the different regions. However, both the versions overestimates/underestimates the frequency of low/high salinity values.

  19. Heavy metals in fish from the Red Sea, Arabian Sea, and Indian Ocean: effect of origin, fish species and size and correlation among the metals.

    PubMed

    Obaidat, Mohammad M; Massadeh, Adnan M; Al-Athamneh, Ahmad M; Jaradat, Qasem M

    2015-04-01

    This study determined the levels of As, Cu, Pb, and Cd in fish from Red Sea, Arabian Sea, and Indian Ocean by graphite furnace atomic absorption spectrophotometry. Metal levels were compared with international standards. The levels among fish types and origin, the relationship among metals, and the correlation between the levels and fish size were statistically tested. Fish type and origin significantly affected the levels. None of the fish contained As, Cu, and Pb above the FAO and EU codes. However, Cd exceeded the Jordanian, FAO, and EC codes from the three origins. As and Cd positively correlated with each other in Arabian Sea fish. As and Pb correlated negatively, but Cu and Cd did not correlate with fish size. This study indicates that Cd is common in fish from the three origins regardless the fish size. This warrants continuous monitoring for heavy metals, especially Cd, in internationally traded fish. PMID:25822330

  20. 76 FR 53831 - Fisheries of the Northeastern United States; Summer Flounder, Scup, and Black Sea Bass Fisheries...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-30

    ... summer flounder, scup, and black sea bass specifications published on December 28, 2010 (75 FR 81498). An... United States; Summer Flounder, Scup, and Black Sea Bass Fisheries; 2011 Summer Flounder, Scup, and Black... flounder, scup, and black sea bass specifications, which established commercial summer flounder...

  1. 75 FR 27219 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-14

    ... United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic Deep-Sea Red Crab Specifications...), Commerce. ACTION: Final rule. SUMMARY: NMFS issues final specifications for the 2010 Atlantic deep- sea red... document is also accessible via the Internet at http://www.nefmc.org . NMFS prepared a Final...

  2. Coupling of millennial-scale changes in sea surface temperature and precipitation off northeastern Brazil with high-latitude climate shifts during the last glacial period

    NASA Astrophysics Data System (ADS)

    Jaeschke, Andrea; Rühlemann, Carsten; Arz, Helge; Heil, Gerrit; Lohmann, Gerrit

    2007-12-01

    High-resolution records of alkenone-derived sea surface temperatures and elemental Ti/Ca ratios from a sediment core retrieved off northeastern Brazil (4°S) reveal short-term climate variability throughout the past 63,000 a. Large pulses of terrigenous sediment discharge, caused by increased precipitation in the Brazilian hinterland, coincide with Heinrich events and the Younger Dryas period. Terrigenous input maxima related to Heinrich events H6-H2 are characterized by rapid cooling of surface water ranging between 0.5° and 2°C. This signature is consistent with a climate model experiment where a reduction of the Atlantic meridional overturning circulation (AMOC) and related North Atlantic cooling causes intensification of NE trade winds and a southward movement of the Intertropical Convergence Zone, resulting in enhanced precipitation off northeastern Brazil. During deglaciation the surface temperature evolution at the core site predominantly followed the Antarctic warming trend, including a cooling, prior to the Younger Dryas period. An abrupt temperature rise preceding the onset of the Bølling/Allerød transition agrees with model experiments suggesting a Southern Hemisphere origin for the abrupt resumption of the AMOC during deglaciation caused by Southern Ocean warming and associated with northward flow anomalies of the South Atlantic western boundary current.

  3. The East Asian Sea: A vanished Cenozoic ocean between the Pacific and Indian oceans revealed by subducted slab constraints

    NASA Astrophysics Data System (ADS)

    Wu, Jonny; Lu, Renqi; Suppe, John; Kanda, Ravi V. S.

    2014-05-01

    We have mapped an extensive 2500 km by 7500 km swath of sub-horizontal slabs at 600 to 1200 km depths that we call the 'East Asian Sea'. The northern margin of the East Asian Sea slabs begin at Taiwan and Japan, and extend south to SE Australia near New Zealand, underlying the Philippine Sea, the Caroline Sea, New Guinea, and northern to eastern Australia. When restored with other mapped slabs under Asia-Oceania, the mapped slabs reveal a vanished ocean that existed between the Pacific and Indian oceans in the Cenozoic. The subduction of the Asian Sea fills a crucial gap in plate tectonic reconstructions of East Asia by accounting for a significant proportion of fast Pacific and Indo-Australian convergence towards Eurasia since 43 Ma, during which time the Pacific moved ~3000 km WNW and Australia moved ~2500 km northward in a near-orthogonal direction relative to a mantle reference. In addition, the Australian plate expanded up to 2000 km at its northern and eastern margins. Slabs were primarily mapped from the MITP08 global P-wave mantle tomographic model (Li et al., 2008) and compared to other global P- and S-wave global tomography. Reconstructed slab lengths were assessed by quantitative flexural slip unfolding of mid-slab surfaces to a spherical Earth surface model. Seismic tomographic volumes were also calculated for selected serial cross-sections. We present a plate tectonic reconstruction with the slab constraints, with the implication that the East Asian Sea was progressively overrun and subducted beneath the Philippine Sea, the Caroline Sea and the expanding Melanesian arcs. Reconstructions to earlier periods indicate the East Asian Sea was originally Pacific or proto-Pacific mantle lithosphere, and was fragmented from the Pacific plate during the major ~45 Ma Eocene motion change. This implies that the East Asian Sea was initially the upper plate of the Mariana and Tonga-Kermadec Western Pacific subduction zones.

  4. Estimation of mean sea surfaces in the north Atlantic, the Pacific and the Indian Ocean using GEOS-3 altimeter data

    NASA Technical Reports Server (NTRS)

    Marsh, J. G.; Martin, T. V.; Mccarthy, J. J.; Chovitz, P. S.

    1979-01-01

    The mean surfaces of several regions of the world's oceans were estimated using GEOS-3 altimeter data. The northwest Atlantic, the northeast Pacific off the coast of California, the Indian Ocean, the southwest Pacific, and the Phillipine Sea are included. These surfaces have been oriented with respect to a common earth center-of-mass system by constraining the separate solutions to conform to precisely determined laser reference control orbits. The same reference orbits were used for all regions assuring continuity of the separate solutions. Radial accuracies of the control orbits were in the order of one meter. The altimeter measured sea surface height crossover differences were minimized by the adjustment of tilt and bias parameters for each pass with the exception of laser reference control passes. The tilt and bias adjustments removed long wavelength errors which were primarily due to orbit error. Ocean tides were evaluated. The resolution of the estimated sea surfaces varied from 0.25 degrees off the east coast of the United States to about 2 degrees in part of the Indian Ocean near Australia. The rms crossover discrepancy after adjustment varied from 30 cm to 70 cm depending upon geographic location. Comparisons of the altimeter derived mean sea surface in the North Atlantic with the 5 feet x 5 feet GEM-8 detailed gravimetric geoid indicated a relative consistency of better than a meter.

  5. Laboratory analysis of the habitat occupancy of the crab Rhithropanopeus harrisii (Gould) in an invaded ecosystem: The north-eastern Baltic Sea

    NASA Astrophysics Data System (ADS)

    Nurkse, Kristiina; Kotta, Jonne; Orav-Kotta, Helen; Pärnoja, Merli; Kuprijanov, Ivan

    2015-03-01

    The Harris mud crab (Rhithropanopeus harrisii) arrived to the Baltic Sea in 1936. It was not until the late 2000es when the species considerably expanded its distribution area towards the northern Baltic Sea and formed a viable and expanding population. This introduction represents an appearance of a completely new function, as such larger epibenthic predators were previously missing from north-eastern Baltic Sea. In order to assess potential impacts of the crab to the invaded ecosystem, knowledge of the crab habitat preferences is required. This study experimentally evaluated the habitat occupancy of the Harris mud crab. The crab stayed more in vegetated boulders compared to unvegetated boulders or sandy habitats. There was an interactive effect between the presence of prey and crab population density with prey availability increasing the crab's affinity towards less favored habitats when population densities were low. Increased aggression between crab individuals increased their affinity towards otherwise less occupied habitats. Less favored habitats were typically inhabited by smaller individuals and presence of prey increased occupancy of some habitats for larger crabs. The experiment demonstrated that the crab may inhabit a large variety of habitats with stronger affinity towards boulder fields covered with the brown macroalga Fucus vesiculosus. This implies stronger impact of crab in such habitats in the invaded ecosystem.

  6. Sea Level Rise, Rainfall and Coastal Flooding in Northeastern U.S. Cities Vivien Gornitz, Radley Horton, Philip Orton, Nickitas Georgas, Alan Blumberg, and Cynthia Rosenzweig

    NASA Astrophysics Data System (ADS)

    Gornitz, V.; Horton, R. M.; Orton, P. M.; Georgas, N.; Blumberg, A. F.; Rosenzweig, C.

    2012-12-01

    Populations and infrastructure along much of the northeastern coast of the United States will become increasingly vulnerable to the impacts of rising sea level and storm surges over the coming century. This vulnerability is amplified by regional land subsidence and likely also by shifts in ocean circulation. Building upon recent studies for the New York City Panel on Climate Change (NPCC), New York State ClimAid assessment, and the latest U.S. National Climate Assessment, we report new regional sea level rise projections based on the latest CMIP-5 global climate models (GCMs) and RCP emission scenarios, adjusted for revised glacial ice melt contributions, and other factors such as gravitational effects, land water storage, and changes in the Atlantic Meriodional Overturning Circulation (AMOC). Over the coming two years, GCM-derived sea level outputs for future decades will be utilized in risk assessments for coastal flooding in New York City, Boston, and Philadelphia, as part of the Consortium for Climate Risk in the Urban Northeast-RISA project. The Stevens Institute Estuarine and Coastal Ocean Model (sECOM) will be used to produce best estimates (including uncertainty ranges) of sea level rise impacts for a wide range of tropical and extra-tropical cyclones for the 2010s, 2050s, and 2080s. Major improvements over prior studies include (a) the use of a detailed, extensively validated ocean model, and (b) inclusion of rainfall and river flow influences on coastal flooding, which affect flood levels in enclosed tidal waterways (e.g., the Hudson and Delaware Rivers), and which are also likely important in coastal confluence zones of impermeable urbanized watersheds. In addition to the sea level rise results, we present initial model validation results for historical storms.

  7. Measurements of the stable carbon isotope composition of dissolved inorganic carbon in the Northeastern Atlantic and Nordic Seas during summer 2012

    NASA Astrophysics Data System (ADS)

    Humphreys, M. P.; Achterberg, E. P.; Griffiths, A. M.; McDonald, A.; Boyce, A. J.

    2015-01-01

    The stable carbon isotope composition of dissolved inorganic carbon (δ13CDIC) in seawater was measured in samples collected during two cruises in the Northeastern Atlantic and Nordic Seas from June to August 2012. One cruise was part of the UK Ocean Acidification research programme, and the other was a repeat hydrographic transect of the Extended Ellett Line. In combination with measurements made of various other variables on these and other cruises, these data can be used to constrain the anthropogenic component of DIC in the interior ocean, and also assist in determining the influence of biological carbon uptake on surface ocean carbonate chemistry. The measurements have been processed, quality-controlled and submitted to an in-preparation global compilation of seawater δ13CDIC data, and are available from the British Oceanographic Data Centre. The observed δ13CDIC values fall in a range from -0.58 to +2.37‰, relative to the Vienna Peedee Belemnite standard. From duplicate samples collected during both cruises, the precision for the 552 results is 0.07‰, which is similar to other published studies of this kind. Data doi:10.5285/09760a3a-c2b5-250b-e053-6c86abc037c0 (Northeastern Atlantic), doi:10.5285/09511dd0-51db-0e21-e053-6c86abc09b95 (Nordic Seas).

  8. Uptake of phytodetritus by benthic foraminifera under oxygen depletion at the Indian margin (Arabian Sea)

    NASA Astrophysics Data System (ADS)

    Enge, A. J.; Witte, U.; Kucera, M.; Heinz, P.

    2014-04-01

    Benthic foraminifera in sediments on the Indian margin of the Arabian Sea, where the oxygen minimum zone (OMZ) impinges on the continental slope, are exposed to particularly severe levels of oxygen depletion. Food supply for the benthic community is high but delivered in distinct pulses during upwelling and water mixing events associated with summer and winter monsoon periods. In order to investigate the response by benthic foraminifera to such pulsed food delivery under oxygen concentrations of less than 0.1 mL L-1 (4.5 μmol L-1), an in situ isotope labeling experiment (13C, 15N) was performed on the western continental slope of India at 540 m water depth (OMZ core region). The assemblage of living foraminifera (>125 μm) in the uppermost centimeter at this depth is characterized by an unexpectedly high population density of 3982 individuals 10 cm-2 and a strong dominance by few calcareous species. For the experiment, we concentrated on the nine most abundant taxa, which constitute 93% of the entire foraminiferal population at 0-1 cm sediment depth. Increased concentrations of 13C and 15N in the cytoplasm indicate that all investigated taxa took up labeled phytodetritus during the 4 day experimental phase. In total, these nine species had assimilated 113.8 mg C m-2 (17.5% of the total added carbon). Uptake of nitrogen by the three most abundant taxa (Bolivina aff. B. dilatata, Cassidulina sp., Bulimina gibba) was 2.7 mg N m-2 (2% of the total added nitrogen). The response to the offered phytodetritus varied largely among foraminiferal species with Uvigerina schwageri being by far the most important species in short-term processing, whereas the most abundant taxa Bolivina aff. B. dilatata and Cassidulina sp. showed comparably low uptake of the offered food. We suggest the observed species-specific differences are related to species biomass and specific feeding preferences. In summary, the experiment in the OMZ core region shows rapid processing of fresh

  9. Holocene tropical western Indian Ocean sea surface temperatures in covariation with climatic changes in the Indonesian region

    NASA Astrophysics Data System (ADS)

    Kuhnert, Henning; Kuhlmann, Holger; Mohtadi, Mahyar; Meggers, Helge; Baumann, Karl-Heinz; Pätzold, Jürgen

    2014-05-01

    The sea surface temperature (SST) of the tropical Indian Ocean is a major component of global climate teleconnections. While the Holocene SST history is documented for regions affected by the Indian and Arabian monsoons, data from the near-equatorial western Indian Ocean are sparse. Reconstructing past zonal and meridional SST gradients requires additional information on past temperatures from the western boundary current region. We present a unique record of Holocene SST and thermocline depth variations in the tropical western Indian Ocean as documented in foraminiferal Mg/Ca ratios and δ18O from a sediment core off northern Tanzania. For Mg/Ca and thermocline δ18O, most variance is concentrated in the centennial to bicentennial periodicity band. On the millennial time scale, an early to mid-Holocene (~7.8-5.6 ka) warm phase is followed by a temperature drop by up to 2°C, leading to a mid-Holocene cool interval (5.6-4.2 ka). The shift is accompanied by an initial reduction in the difference between surface and thermocline foraminiferal δ18O, consistent with the thickening of the mixed layer and suggestions of a strengthened Walker circulation. However, we cannot confirm the expected enhanced zonal SST gradient, as the cooling of similar magnitude had previously been found in SSTs from the upwelling region off Sumatra and in Flores air temperatures. The SST pattern probably reflects the tropical Indian Ocean expression of a large-scale climate anomaly rather than a positive Indian Ocean Dipole-like mean state.

  10. 75 FR 49420 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-13

    ... establish a target TAC greater than that recommended by the Council, the initial final rule (75 FR 27219... on June 22, 2010 (75 FR 35435), requesting public comment on the revised recommended catch level... (TAC) and corresponding fleet days-at-sea (DAS) allocation for the Atlantic deep- sea red crab...

  11. A model study of the seasonality of sea surface temperature and circulation in the Atlantic North-Eastern Tropical Upwelling System.

    NASA Astrophysics Data System (ADS)

    Faye, Saliou; Lazar, Alban; Sow, Bamol; Gaye, Amadou

    2015-09-01

    The climatological seasonal cycle of the sea surface temperature (SST) in the north-eastern tropical Atlantic (7-25°N, 26-12°W) is studied using a mixed layer heat budget in a regional ocean general circulation model. The region, which experiences one of the larger SST cycle in the tropics, forms the main part of the Guinea Gyre. It is characterized by a seasonally varying open ocean and coastal upwelling system, driven by the movements of the intertropical convergence zone (ITCZ). The model annual mean heat budget has two regimes schematically. South of roughly 12°N, advection of equatorial waters, mostly warm, and warming by vertical mixing, is balanced by net air-sea flux. In the rest of the domain, a cooling by vertical mixing, reinforced by advection at the coast, is balanced by the air-sea fluxes. Regarding the seasonal cycle, within a narrow continental band, in zonal mean, the SST early decrease (from September, depending on latitude, until December) is driven by upwelling dynamics off Senegal and Mauritania (15°-20°N), and instead by air-sea fluxes north and south of these latitudes. Paradoxically, the later peaks of upwelling intensity (from March to July, with increasing latitude) essentially damp the warming phase, driven by air-sea fluxes. The open ocean cycle to the west, is entirely driven by the seasonal net air-sea fluxes. The oceanic processes significantly oppose it, but for winter north of ~18°N. Vertical mixing in summer-autumn tends to cool (warm) the surface north (south) of the ITCZ, and advective cooling or warming by the geostrophic Guinea Gyre currents and the Ekman drift. This analysis supports previous findings on the importance of air-sea fluxes offshore. It mainly offers quantitative elements on the modulation of the SST seasonal cycle by the ocean circulation, and particularly by the upwelling dynamics. Keywords: SST, upwelling, circulation, heat budget, observations, modeling

  12. Phylogenetic relationships elucidate colonization patterns in the intertidal grazers Osilinus Philippi, 1847 and Phorcus Risso, 1826 (Gastropoda: Trochidae) in the northeastern Atlantic Ocean and Mediterranean Sea.

    PubMed

    Donald, Kirsten M; Preston, Joanne; Williams, Suzanne T; Reid, David G; Winter, David; Alvarez, Raquel; Buge, Barbara; Hawkins, Stephen J; Templado, Jose; Spencer, Hamish G

    2012-01-01

    Snails in the closely related trochid genera Phorcus Risso, 1826 and Osilinus Philippi, 1847 are ecologically important algal grazers in the intertidal zone of the northeastern Atlantic Ocean and Mediterranean Sea. Here we present the first complete molecular phylogeny for these genera, based on the nuclear 28S rRNA gene and the mitochondrial 16S rRNA and COI genes, and show that the current classification is erroneous. We recognize nine species in a single genus, Phorcus: estimated by BEAST analysis, this arose 30 (± 10) Ma; it consists of two subgenera, Phorcus and Osilinus, which we estimate diverged 14 (± 4.5) Ma. Osilinus kotschyi, from the Arabian and Red Seas, is not closely related and is tentatively referred to Priotrochus Fischer, 1879. Our phylogeny allows us to address biogeographical questions concerning the origins of the Mediterranean and Macaronesian species of this group. The former appear to have evolved from Atlantic ancestors that invaded the Mediterranean on several occasions after the Zanclean Flood, which ended the Messinian Salinity Crisis 5.3 Ma; whereas the latter arose from several colonizations of mainland Atlantic ancestors within the last 3 (± 1.5) Ma. PMID:21945534

  13. Evaluation of ecosystem status in the shelf-slope zone of the northeastern Black Sea based on the trophic index (TRIX)

    NASA Astrophysics Data System (ADS)

    Romanova, N. D.; Chasovnikov, V. K.; Arashkevich, E. G.; Mosharov, S. A.; Nikishina, A. B.; Kostyleva, A. V.; Louppova, N. E.

    2016-01-01

    The water conditions and trophic status in the shelf-slope zone and bays of the northeastern Black Sea were evaluated on the basis of monitoring data from 2007-2014. It has been shown that the concentrations of nutrients and chlorophyll "a" in the studied area are at the level of the pristine period (of the late 1970s). The concentration of mineral nitrogen in the surface water layer varied from 0.19 to 5.64 μM. The concentration of phosphates differed from analytical zero to 0.56 μM. The concentration of chlorophyll "a" in different seasons ranged from 0.24 to 0.89 μg/L. The trophic index characterizes the status of the marine shelf ecosystem near Gelendzhik city as "excellent" even in the bays. Significant year-to-year differences in the index were not detected. The range between the values of the trophic index in the bays and open sea was low (3.7 and 3.2, respectively).

  14. AMS-dated mollusks in beach ridges and berms document Holocene sea-level and coastal changes in northeastern Kuwait Bay

    NASA Astrophysics Data System (ADS)

    Reinink-Smith, Linda M.

    2015-09-01

    In northeastern Kuwait, ancient beach ridges and associated berms are separated from the present shoreline by a 4-6 km-wide sabkha. A diverse mollusk fauna in the beach ridges attests to a former open marine environment. A total of 21 AMS dates were obtained in this study. Thirteen mollusk samples from beach ridges yielded AMS dates ranging from ~ 6990 cal yr BP in the southeast to ~ 3370 cal yr BP in the northwest, suggesting a southeast to northwest age progression during the Holocene transgression. In contrast, four samples from berms throughout the study area yielded AMS dates of 5195-3350 cal yr BP showing no age progression; these berms consist largely of Conomurex persicus gastropods that aggregated by storms during a highstand at ~ 5000-3500 cal yr BP. The berms are presently at ~ + 6 m above sea level, 2-3 m above the beach ridges. Human settlements were common on the ridge crests before and after the highstand. Regression to present-day sea level commenced after the highstand, which is when the sabkha began forming. A landward, marine-built terrace, which yielded AMS dates > 43,500 14C yr BP, probably formed during Marine Oxygen Isotope Stage 5e and hence is not genetically related to the beach ridges.

  15. Quantification of the Early Small-Scale Fishery in the North-Eastern Baltic Sea in the Late 17th Century

    PubMed Central

    Verliin, Aare; Ojaveer, Henn; Kaju, Katre; Tammiksaar, Erki

    2013-01-01

    Historical perspectives on fisheries and related human behaviour provide valuable information on fishery resources and their exploitation, helping to more appropriately set management targets and determine relevant reference levels. In this study we analyse historical fisheries and fish trade at the north-eastern Baltic Sea coast in the late 17th century. Local consumption and export together amounted to the annual removal of about 200 tonnes of fish from the nearby sea and freshwater bodies. The fishery was very diverse and exploited altogether one cyclostome and 17 fish species with over 90% of the catch being consumed locally. The exported fish consisted almost entirely of high-valued species with Stockholm (Sweden) being the most important export destination. Due to rich political history and natural features of the region, we suggest that the documented evidence of this small-scale fishery should be considered as the first quantitative summary of exploitation of aquatic living resources in the region and can provide a background for future analyses. PMID:23861914

  16. Basin-scale estimates of pelagic and coral reef calcification in the Red Sea and Western Indian Ocean.

    PubMed

    Steiner, Zvi; Erez, Jonathan; Shemesh, Aldo; Yam, Ruth; Katz, Amitai; Lazar, Boaz

    2014-11-18

    Basin-scale calcification rates are highly important in assessments of the global oceanic carbon cycle. Traditionally, such estimates were based on rates of sedimentation measured with sediment traps or in deep sea cores. Here we estimated CaCO3 precipitation rates in the surface water of the Red Sea from total alkalinity depletion along their axial flow using the water flux in the straits of Bab el Mandeb. The relative contribution of coral reefs and open sea plankton were calculated by fitting a Rayleigh distillation model to the increase in the strontium to calcium ratio. We estimate the net amount of CaCO3 precipitated in the Red Sea to be 7.3 ± 0.4·10(10) kg·y(-1) of which 80 ± 5% is by pelagic calcareous plankton and 20 ± 5% is by the flourishing coastal coral reefs. This estimate for pelagic calcification rate is up to 40% higher than published sedimentary CaCO3 accumulation rates for the region. The calcification rate of the Gulf of Aden was estimated by the Rayleigh model to be ∼1/2 of the Red Sea, and in the northwestern Indian Ocean, it was smaller than our detection limit. The results of this study suggest that variations of major ions on a basin scale may potentially help in assessing long-term effects of ocean acidification on carbonate deposition by marine organisms. PMID:25368148

  17. Basin-scale estimates of pelagic and coral reef calcification in the Red Sea and Western Indian Ocean

    PubMed Central

    Steiner, Zvi; Erez, Jonathan; Shemesh, Aldo; Yam, Ruth; Katz, Amitai; Lazar, Boaz

    2014-01-01

    Basin-scale calcification rates are highly important in assessments of the global oceanic carbon cycle. Traditionally, such estimates were based on rates of sedimentation measured with sediment traps or in deep sea cores. Here we estimated CaCO3 precipitation rates in the surface water of the Red Sea from total alkalinity depletion along their axial flow using the water flux in the straits of Bab el Mandeb. The relative contribution of coral reefs and open sea plankton were calculated by fitting a Rayleigh distillation model to the increase in the strontium to calcium ratio. We estimate the net amount of CaCO3 precipitated in the Red Sea to be 7.3 ± 0.4·1010 kg·y−1 of which 80 ± 5% is by pelagic calcareous plankton and 20 ± 5% is by the flourishing coastal coral reefs. This estimate for pelagic calcification rate is up to 40% higher than published sedimentary CaCO3 accumulation rates for the region. The calcification rate of the Gulf of Aden was estimated by the Rayleigh model to be ∼1/2 of the Red Sea, and in the northwestern Indian Ocean, it was smaller than our detection limit. The results of this study suggest that variations of major ions on a basin scale may potentially help in assessing long-term effects of ocean acidification on carbonate deposition by marine organisms. PMID:25368148

  18. Shoreline changes in a rising sea level context: The example of Grande Glorieuse, Scattered Islands, Western Indian Ocean

    NASA Astrophysics Data System (ADS)

    Testut, Laurent; Duvat, Virginie; Ballu, Valérie; Fernandes, Rui M. S.; Pouget, Frédéric; Salmon, Camille; Dyment, Jérome

    2016-04-01

    This paper provides baseline data on absolute and relative sea level variations and shoreline changes in the Scattered Islands region of the Indian Ocean, based on aerial image analysis, satellite altimetry and field observations and in situ measurements from the 2009 and 2011 TAAF scientific expeditions. The analysis shows the importance of regular observations and monitoring of these islands to better understand reef island responses to climate stressors. We show that Grande Glorieuse Island has increased in area by 7.5 ha between 1989 and 2003, predominantly as a result of shoreline accretion: accretion occurred over 47% of shoreline length, whereas 26% was stable and 28% was eroded. Topographic transects and field observations show that the accretion is due to sediment transfer from the reef outer slopes to the reef flat and then to the beach. This accretion occurred in a context of sea level rise: sea level has risen by about 6 cm in the last twenty years and the island height is probably stable or very slowly subsiding. This island expansion during a period of rising sea level demonstrates that sea level rise is not the primary factor controlling the shoreline changes. This paper highlights the key role of non-climate factors in changes in island area, especially sediment availability and transport. We also evidence rotation of the island, underscoring the highly dynamic nature of reef islands.

  19. Uptake of phytodetritus by benthic foraminifera under oxygen depletion at the Indian Margin (Arabian Sea)

    NASA Astrophysics Data System (ADS)

    Enge, A. J.; Witte, U.; Kucera, M.; Heinz, P.

    2013-09-01

    Benthic foraminifera in sediments on the Indian margin of the Arabian Sea where the oxygen minimum zone (OMZ) impinges on the continental slope are exposed to particularly severe levels of oxygen depletion. Food supply for the benthic community is high but delivered in distinct pulses during upwelling and water mixing events associated with summer and winter monsoon periods. In order to investigate the response by benthic foraminifera to such pulsed food delivery under oxygen concentrations of less than 0.1 mL L-1 (4.5 μmol L-1), an in situ isotope labeling experiment (13C, 15N) was performed at the western continental slope of India at 540 m water depth (OMZ core region). The assemblage of living foraminifera (>125 μm) in the uppermost centimeter at this depth is characterized by an unexpectedly high population density of 3982 ind. 10 cm-2 and a strong dominance by few calcareous species. For the experiment, we concentrated on the nine most abundant taxa, which constitute 93% of the entire foraminifera population at 0-1 cm sediment depth. Increased concentrations of 13C and 15N in the cytoplasm indicate that all investigated taxa took up the labeled phytodetritus during the 4 day experimental phase. In total, these nine species had assimilated 113.8 mg C m-2 (17.5% of the total added carbon). The uptake of nitrogen by the three most abundant taxa (Bolivina aff. B. dilatata, Cassidulina sp., Bulimina gibba) was 2.7 mg N m-2 (2% of the total added nitrogen) and showed the successful application of 15N as tracer in foraminiferal studies. The short-term response to the offered phytodetritus varied largely among foraminiferal species with Uvigerina schwageri being by far the most important species in short-term processing whereas the most abundant taxa Bolivina aff. B. dilatata and Cassidulina sp. showed comparably low uptake of the offered food. We suggest that the observed species-specific differences are related to individual biomass of species and to specific

  20. Volcanological and petrological evolution of Barren Island (Andaman Sea, Indian Ocean)

    NASA Astrophysics Data System (ADS)

    Chandrasekharam, Dornadula; Santo, Alba P.; Capaccioni, Bruno; Vaselli, Orlando; Alam, Mohammad Ayaz; Manetti, Piero; Tassi, Franco

    2009-08-01

    The Island of Barren (Andaman Sea, Indian Ocean) consists of a horseshoe-shaped caldera opened to the west that was formed by either a giant, lateral landslide of the original volcanic cone or a vertical collapse of a surficial magma chamber due to a paroxysmal eruption. The reconstruction of the pre-and post-calderic activity indicates that the subaerial volcanic history of Barren Island was characterized by effusive activities accompanied by subordinate explosive (scoria fall) eruptions. The collapse of the central portion of the edifice terminated this mainly effusive phase. The inner flanks and the rim of the depression are covered by a 20 m thick sequence of breccias and tuffs. Beds are structurally massive with steep fronts, likely due to secondary mass flowage. The lack of caldera-forming eruption together with the absence of chemically evolved magmas could suggest a lateral landslide as the most probable process responsible for the caldera formation. The active polygenic tuff cone, presently occupying the inner portion of the caldera, consists of at least five coalescent summit craters and four eccentric spatter cones at the base. These features are attributed to the historic activities that are dominated by the emplacement of lava flows and pyroclastic deposits (e.g. 1803, 1991, 1995 and, possibly, 2000 eruptions). Lava flows moved westward from lateral spatter cones and occasionally reached the sea. A few months after the 2004 tsunami and Sumatra earthquake, Barren Island volcano violently resumed its eruptive activity that lasted for almost two years. The volcanic products ejected from May 2005 eruption have covered the historic lava flows and pyroclastic deposits. Petrologically, the lava flows show a narrow compositional variation, from low-K basalts to basaltic andesites. Pre-caldera magmas display a general less evolved composition and a certain variability of the Sr isotopic ratios (0.70385-0.70400); post-caldera magmas are compositionally more

  1. Measurements of the stable carbon isotope composition of dissolved inorganic carbon in the northeastern Atlantic and Nordic Seas during summer 2012

    NASA Astrophysics Data System (ADS)

    Humphreys, M. P.; Achterberg, E. P.; Griffiths, A. M.; McDonald, A.; Boyce, A. J.

    2015-06-01

    The stable carbon isotope composition of dissolved inorganic carbon (δ13CDIC) in seawater was measured in a batch process for 552 samples collected during two cruises in the northeastern Atlantic and Nordic Seas from June to August 2012. One cruise was part of the UK Ocean Acidification research programme, and the other was a repeat hydrographic transect of the Extended Ellett Line. In combination with measurements made of other variables on these and other cruises, these data can be used to constrain the anthropogenic component of dissolved inorganic carbon (DIC) in the interior ocean, and to help to determine the influence of biological carbon uptake on surface ocean carbonate chemistry. The measurements have been processed, quality-controlled and submitted to an in-preparation global compilation of seawater δ13CDIC data, and are available from the British Oceanographic Data Centre. The observed δ13CDIC values fall in a range from -0.58 to +2.37 ‰, relative to the Vienna Pee Dee Belemnite standard. The mean of the absolute differences between samples collected in duplicate in the same container type during both cruises and measured consecutively is 0.10 ‰, which corresponds to a 1σ uncertainty of 0.09 ‰, and which is within the range reported by other published studies of this kind. A crossover analysis was performed with nearby historical δ13CDIC data, indicating that any systematic offsets between our measurements and previously published results are negligible. Data doi:10.5285/09760a3a-c2b5-250b-e053-6c86abc037c0 (northeastern Atlantic), doi:10.5285/09511dd0-51db-0e21-e053-6c86abc09b95 (Nordic Seas).

  2. Evaluating coastal landscape response to sea-level rise in the northeastern United States: approach and methods

    USGS Publications Warehouse

    Lentz, Erika E.; Stippa, Sawyer R.; Thieler, E. Robert; Plant, Nathaniel G.; Gesch, Dean B.; Horton, Radley M.

    2015-01-01

    The U.S. Geological Survey is examining effects of future sea-level rise on the coastal landscape from Maine to Virginia by producing spatially explicit, probabilistic predictions using sea-level projections, vertical land movement rates (due to isostacy), elevation data, and land-cover data. Sea-level-rise scenarios used as model inputs are generated by using multiple sources of information, including Coupled Model Intercomparison Project Phase 5 models following representative concentration pathways 4.5 and 8.5 in the Intergovernmental Panel on Climate Change Fifth Assessment Report. A Bayesian network is used to develop a predictive coastal response model that integrates the sea-level, elevation, and land-cover data with assigned probabilities that account for interactions with coastal geomorphology as well as the corresponding ecological and societal systems it supports. The effects of sea-level rise are presented as (1) level of landscape submergence and (2) coastal response type characterized as either static (that is, inundation) or dynamic (that is, landform or landscape change). Results are produced at a spatial scale of 30 meters for four decades (the 2020s, 2030s, 2050s, and 2080s). The probabilistic predictions can be applied to landscape management decisions based on sea-level-rise effects as well as on assessments of the prediction uncertainty and need for improved data or fundamental understanding. This report describes the methods used to produce predictions, including information on input datasets; the modeling approach; model outputs; data-quality-control procedures; and information on how to access the data and metadata online.

  3. The Owen Ridge uplift in the Arabian Sea: Implications for the sedimentary record of Indian monsoon in Late Miocene

    NASA Astrophysics Data System (ADS)

    Rodriguez, Mathieu; Chamot-Rooke, Nicolas; Huchon, Philippe; Fournier, Marc; Delescluse, Matthias

    2014-05-01

    The pelagic cover of the Owen Ridge in the Arabian Sea recorded the evolution of the Indian monsoon since the Middle Miocene. The uplift of the Owen Ridge resulted from tectonic processes along the previously unidentified Miocene India-Arabia plate boundary. Based on seismic reflection data tied with deep-sea drilling to track the Miocene India-Arabia plate boundary, we propose a new timing for the uplift of the Owen Ridge and highlight its impact on the record of climate changes in pelagic sediments. The new dataset reveals a fracture zone east of the Owen Ridge corresponding to the fossil plate boundary, and documents that the main uplift of the Owen Ridge occurred close to ˜8.5 Ma, and is coeval with a major uplift of the east Oman margin. Late Miocene deformation at the India-Arabia plate boundary is also coeval with the onset of intra-plate deformation in the Central Indian Ocean, suggesting a kinematic change of India and surrounding plates in the Late Miocene. The uplift of the Owen Ridge above the lysocline at ˜8.5 Ma accounts for a better preservation of Globigerina bulloides in the pelagic cover, previously misinterpreted as the result of a monsoon intensification event.

  4. Sedimentary record on the Indian Summer Monsoon since the Last Glacial Maximum: Evidence from the southeastern Andaman Sea

    NASA Astrophysics Data System (ADS)

    Shi, Xuefa; Liu, Shengfa; Cao, Peng; Khokiattiwong, Somkiat; Kornkanitnan, Narumol

    2016-04-01

    The Indian Summer Monsoon (ISM) generated by across-equatorial pressure gradient between the Asian continent and the southern Indian Ocean is a major component of the Asian monsoon system and establishes interactions among the ocean, land and atmosphere. Provenance and paleoclimate changes in the Andaman Sea during the last 26 ka were reconstructed from high-resolution records of grain-size, major elements and Sr-Nd isotopes in core ADM-9. The values of ɛNd(0) and 87Sr/86Sr were in good agreement with those of Irrawaddy River sediments, indicating a common source of origin. Two sensitive grain-size intervals (3.4-7.5 and 16.8-21.2 μm) were identified; the former was controlled primarily by sea-level change, whereas the latter was related to Irrawaddy River discharge and South-west Current transport driven by the ISM. Proxies of chemical weathering (K/Al) and terrigenous input (Ti/Ca) coupled with sensitive grain-size interval (16.8-21.2 μm population) revealed that the ISM was weak during ~15-26 ka BP and then strengthened gradually to a maximum during ~7-9 ka BP; subsequently, the ISM exhibited a generally declining trend to ~2 ka BP. The variation of the ISM recorded in this work is consistent with ISM variations observed in an open area in the northern Indian Ocean and in adjacent continents, implying the evolution of the Asia summer monsoon since 26 ka.

  5. 76 FR 39369 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fishery; Amendment 3

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-06

    ...NMFS proposes regulations to implement Amendment 3 to the Atlantic Deep-Sea Red Crab Fishery Management Plan (Red Crab FMP). The New England Fishery Management Council (Council) developed Amendment 3 to bring the Red Crab FMP into compliance with the annual catch limit (ACL) and accountability measure (AM) requirements of the Magnuson- Stevens Fishery Conservation and Management Act......

  6. 75 FR 35435 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab Fisheries; 2010 Atlantic...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-22

    ... crab emergency action implemented by NMFS (74 FR 9770, March 6, 2009), i.e., a target TAC of 3.56..., 2010 final rule implementing the FY 2010 red crab specifications (75 FR 27219), that rule set the... catch (TAC) and a fleet-wide days-at-sea (DAS) allocation. However, the implementing regulations for...

  7. 76 FR 60379 - Fisheries of the Northeastern United States; Atlantic Deep-Sea Red Crab; Amendment 3

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-29

    ... measures in Amendment 3 published in the Federal Register on July 6, 2011 (76 FR 39369), with public... Amendment 3 was published in the Federal Register on June 22, 2011 (76 FR 36511), with public comments... United States; Atlantic Deep-Sea Red Crab; Amendment 3 AGENCY: National Marine Fisheries Service...

  8. Centennial-scale teleconnection between North Atlantic sea surface temperatures and the Indian summer monsoon during the Holocene

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaojian; Jin, Liya; Jia, Wanna

    2016-05-01

    Proxy records have shown that abrupt changes in the Indian summer monsoon (ISM) are closely linked to cold events in the North Atlantic at centennial timescales during the Holocene. However, mechanisms for these co-occurring phenomena are not fully understood. This study uses simulation results from a coupled atmosphere-ocean-sea-ice general circulation model forced by astronomical variations to investigate how summer (June, July, August and September) North Atlantic sea surface temperatures (SSTs) may have influenced the ISM at centennial timescales during the Holocene (9.5-0 ka BP). Our analyses identified an intimate relationship between the North Atlantic tripole SST (NATS) mode and the ISM. The NATS mode can affect the ISM in several ways. First, air-sea interactions over the tropical Atlantic can induce negative tropospheric temperature (TT) anomalies over the Indian Ocean, resulting in a strengthened meridional TT gradient favorable to a prolonged monsoonal rainy season. Second, a positive NATS mode tends to induce closed zonal vertical circulation over the tropical Atlantic, North Africa and the tropical Indian Ocean, creating anomalous convergence over India, and hence an enhanced ISM. Third, westerly surface wind anomalies, related to the NATS mode and coursing over the Arabian Sea, can increase moisture delivery to the monsoon region, causing enhanced rainfall in India. This mechanism resembles a decadal-scale mechanism that operates in the present-day climate. We also compared the Atlantic multidecadal oscillation (AMO), an alternative North Atlantic SST mode, with the NATS mode to determine their relationships to the ISM. A Holocene transient simulation indicates that the AMO's trend has diverged from that of the ISM since 5.5 ka BP, due to inverse SST trends over the tropical and extratropical North Atlantic. This latter trend leads to a much weaker relationship between the AMO and the ISM, relative to that observed between the NATS mode and the ISM

  9. Decadal- to biennial scale variability of planktic foraminifera in the northeastern Arabian Sea during the last two millennia: evidence for winter monsoon forcing mechanisms

    NASA Astrophysics Data System (ADS)

    Munz, Philipp; Lückge, Andreas; Siccha, Michael; Kucera, Michal; Schulz, Hartmut

    2015-04-01

    The Asian monsoon system is controlling the hydrologic cycle, and thus the agricultural and economic prosperity of the worlds most densely populated region. Strong and moisture-laden winds from the southwest induce upwelling and significant productivity in the western Arabian Sea during boreal summer. During boreal winter, weaker dry and cold surface winds from the northeast nourish ocean productivity mainly in the northeastern Arabian Sea. Instrumental records spanning the last century are too short to understand how the monsoon system reacts to external forcing mechanisms and to accurately determine its natural variability. Compared to the summer monsoon component, the dynamics of the winter monsoon are virtually unknown, due to the lack of adequate archives that are affected only by winter conditions. Here we present a decadal- to biennial-scale resolution record of past winter monsoon variability over the last two millennia, based on census counts of planktic foraminifera from two laminated sediment cores collected offshore Pakistan. One shorter box core (SO90-39KG) spans the last 250 years with an average ~2-year resolution, whereas the longer piston core (SO130-275KL) spans the last 2,100 years with a 10-year resolution. We use Globigerina falconensis as a faunal indicator for winter conditions, a species that is most abundant during winter in the NE Arabian Sea (Peeters and Brummer, 2002; Schulz et al., 2002). Our results show that during the past 2,100 years G. falconensis varied with significant periodicities centered on ˜ 60, ˜ 53, ˜ 40, ˜ 34 and ˜ 29 years per cycle. Some of these periods closely match cycles that are known from proxy records of solar irradiance, suggesting a solar forcing on winter monsoon variability. During the past 250 years G. falconensis varied in correlation with the (11-year) Schwabe and the (22-year) Hale solar cycles. Furthermore, a significant ˜ 7 year cyclicity could indicate a teleconnection to the El Niño Southern

  10. 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.

  11. Assimilation of the seabird and ship drift data in the north-eastern sea of Japan into an operational ocean nowcast/forecast system

    NASA Astrophysics Data System (ADS)

    Miyazawa, Yasumasa; Guo, Xinyu; Varlamov, Sergey M.; Miyama, Toru; Yoda, Ken; Sato, Katsufumi; Kano, Toshiyuki; Sato, Keiji

    2015-12-01

    At the present time, ocean current is being operationally monitored mainly by combined use of numerical ocean nowcast/forecast models and satellite remote sensing data. Improvement in the accuracy of the ocean current nowcast/forecast requires additional measurements with higher spatial and temporal resolution as expected from the current observation network. Here we show feasibility of assimilating high-resolution seabird and ship drift data into an operational ocean forecast system. Data assimilation of geostrophic current contained in the observed drift leads to refinement in the gyre mode events of the Tsugaru warm current in the north-eastern sea of Japan represented by the model. Fitting the observed drift to the model depends on ability of the drift representing geostrophic current compared to that representing directly wind driven components. A preferable horizontal scale of 50 km indicated for the seabird drift data assimilation implies their capability of capturing eddies with smaller horizontal scale than the minimum scale of 100 km resolved by the satellite altimetry. The present study actually demonstrates that transdisciplinary approaches combining bio-/ship- logging and numerical modeling could be effective for enhancement in monitoring the ocean current.

  12. Short-term hydrophysical and biological variability over the northeastern Black Sea continental slope as inferred from multiparametric tethered profiler surveys

    NASA Astrophysics Data System (ADS)

    Ostrovskii, Alexander; Zatsepin, Andrey

    2011-06-01

    This presentation introduces a new ocean autonomous profiler for multiparametric surveys at fixed geographical locations. The profiler moves down and up along a mooring line, which is taut vertically between a subsurface flotation and an anchor. This observational platform carries such modern oceanographic equipment as the Nortek Aquadopp-3D current meter and the Teledyne RDI Citadel CTD-ES probe. The profiler was successfully tested in the northeastern Black Sea during 2007-2009. By using the profiler, new data on the layered organization of the marine environment in the waters over the upper part of the continental slope were obtained. The temporal variability of the fine-scale structure of the acoustic backscatter at 2 MHz was interpreted along with biooptical and chemical data. The patchy patterns of the acoustic backscatter were associated with physical and biological processes such as the advection, propagation of submesoscale eddy, thermocline displacement, and diel migration of zooplankton. Further applications of the multidisciplinary moored profiler technology are discussed.

  13. Assimilation of the seabird and ship drift data in the north-eastern sea of Japan into an operational ocean nowcast/forecast system.

    PubMed

    Miyazawa, Yasumasa; Guo, Xinyu; Varlamov, Sergey M; Miyama, Toru; Yoda, Ken; Sato, Katsufumi; Kano, Toshiyuki; Sato, Keiji

    2015-01-01

    At the present time, ocean current is being operationally monitored mainly by combined use of numerical ocean nowcast/forecast models and satellite remote sensing data. Improvement in the accuracy of the ocean current nowcast/forecast requires additional measurements with higher spatial and temporal resolution as expected from the current observation network. Here we show feasibility of assimilating high-resolution seabird and ship drift data into an operational ocean forecast system. Data assimilation of geostrophic current contained in the observed drift leads to refinement in the gyre mode events of the Tsugaru warm current in the north-eastern sea of Japan represented by the model. Fitting the observed drift to the model depends on ability of the drift representing geostrophic current compared to that representing directly wind driven components. A preferable horizontal scale of 50 km indicated for the seabird drift data assimilation implies their capability of capturing eddies with smaller horizontal scale than the minimum scale of 100 km resolved by the satellite altimetry. The present study actually demonstrates that transdisciplinary approaches combining bio-/ship- logging and numerical modeling could be effective for enhancement in monitoring the ocean current. PMID:26633309

  14. Assimilation of the seabird and ship drift data in the north-eastern sea of Japan into an operational ocean nowcast/forecast system

    PubMed Central

    Miyazawa, Yasumasa; Guo, Xinyu; Varlamov, Sergey M.; Miyama, Toru; Yoda, Ken; Sato, Katsufumi; Kano, Toshiyuki; Sato, Keiji

    2015-01-01

    At the present time, ocean current is being operationally monitored mainly by combined use of numerical ocean nowcast/forecast models and satellite remote sensing data. Improvement in the accuracy of the ocean current nowcast/forecast requires additional measurements with higher spatial and temporal resolution as expected from the current observation network. Here we show feasibility of assimilating high-resolution seabird and ship drift data into an operational ocean forecast system. Data assimilation of geostrophic current contained in the observed drift leads to refinement in the gyre mode events of the Tsugaru warm current in the north-eastern sea of Japan represented by the model. Fitting the observed drift to the model depends on ability of the drift representing geostrophic current compared to that representing directly wind driven components. A preferable horizontal scale of 50 km indicated for the seabird drift data assimilation implies their capability of capturing eddies with smaller horizontal scale than the minimum scale of 100 km resolved by the satellite altimetry. The present study actually demonstrates that transdisciplinary approaches combining bio-/ship- logging and numerical modeling could be effective for enhancement in monitoring the ocean current. PMID:26633309

  15. Occurrence, distribution and expression of gas seeps and gas hydrates on the northeastern continental slope of Sakhalin Island, Sea of Okhotsk

    NASA Astrophysics Data System (ADS)

    Jin, Y.; Hong, J.; Baranov, B.; Shoji, H.; Obzhirov, A.

    2012-12-01

    The northeastern Sakhalin continental slope (NESS), Okhotsk Sea is characterized by an abundant occurrence of gas hydrate and gas seeps. Under the frameworks of Korea-Russia-Japan international projects (CHAOS and SSGH), we have carried out multidisciplinary surveys to investigate gas hydrate accumulation and active gas seepage phenomena on the NESS since 2003. During the surveys, about moe than nine hundred gas seeps were detected in a 2,650 km2 area of the NESS. Active gas seeps on the NESS were evident from features in the water column, on the seafloor, and in the subsurface by geophysical methods: well-defined hydroacoustic anomalies (gas flares), side-scan sonar seafloor structures with high backscatter intensity (seepage structures), bathymetric structures (pockmarks and mounds), and gas- and gas-hydrate-related seismic features (bottom-simulating reflectors, gas chimneys, high-amplitude reflectors, and acoustic blanking). They are also evident from ground-truths; high methane concentrations in seawater, near-bottom gas hydrates and antigenic carbonates. These features are generally related; a gas flare emits at a topographic mound with high backscatter intensity, below which a gas chimney is present. We interpret that gas chimneys producing enhanced reflection on high-resolution seismic profiles are active pathways for upward gas migration to the seafloor.

  16. Hydrocarbons in waters and bottom sediments of coastal areas in the northeastern part of the Black Sea

    NASA Astrophysics Data System (ADS)

    Nemirovskaya, I. A.; Lisitzin, A. P.

    2015-09-01

    Data on the content and composition of aliphatic and polycyclic aromatic hydrocarbons in the surface layer of water and bottom sediments are presented. The data were compared to the distribution of the total organic carbon, particulate matter, lipids, and chlorophyll in the Gelendzhik and Golubaya bays, as well as in the Greater Sochi area. The intense transformation processes of organic compounds within the water mass and water-bottom interface have resulted in the prevalence of natural components in the alkane composition of the bottom sediments in the areas of the Black Sea considered. The riverine and marine water mixing zone acts as a geochemical barrier preventing the supply of the bulk of river-transferred pollutants to the open sea areas.

  17. Effect of Pacific warm and cold events on the sea ice behavior in the Indian sector of the Southern Ocean

    NASA Astrophysics Data System (ADS)

    Deb, Pranab; Dash, Mihir Kumar; Pandey, Prem Chand

    2014-02-01

    The teleconnections between sea ice area (SIA) in the Indian Ocean Sector (IOS) of the Southern Ocean (20-90°E) and the El Niño Southern Oscillation (ENSO) for the period 1982-2009 are studied. The ENSO years are divided into La Niña, El Niño and El Niño Modoki years. The sea surface temperature anomalies averaged over the Niño 3.4 (SST3.4A) region (120-170°W, 5°N-5°S) are used as proxy for ENSO. A significantly stronger negative correlation between SST3.4A and SIA anomalies is found at a positive lag of 6-12 months in 50-80°E region than elsewhere in the IOS. Variations in sea level pressure anomalies over the Antarctic continent and the subpolar regions play an important role in shaping the surface wind. Variation in the surface wind along with the changes in sea surface temperature (SST), sea ice drift and surface air temperature (SAT) shape the sea ice cover over the region. Composites show that the winters following La Niña years are associated with more SIA compared to that of ENSO-neutral years. This is attributed to the increase in sea level pressure gradient between the Antarctic land mass and the subpolar region, which enhances the southerly wind and results in a reduction in SAT. Also, anomalous northward advection of sea ice increases the SIC over the outer margin of the sea ice cover. The in-phase relation among SAT, SST and sea ice advection results in an increase in SIA. Also, a weaker Regional Ferrel Cell (RFC) during this period results in the reduction of poleward heat transport and contributes to the increase in SIA. During the winters following El Niño years, interaction among anomalous easterlies, wind-induced sea ice motion, SAT anomalies and heat transport by the RFC increases (decreases) the SIA in the western (eastern) part of the high correlation region. During El Niño Modoki years, an increase in SST and presence of warmer surface air over the high correlation region reduce SIA during summer as well as the winter following it

  18. Report on two deep-water caridean shrimp species (Crustacea: Decapoda: Caridea: Alvinocarididae, Acanthephyridae) from the northeastern South China Sea.

    PubMed

    Li, Xinzheng

    2015-01-01

    Two deep-water species of caridean shrimps collected during recent dives by the Chinese manned submersible "Jiaolong" represents new records for the South China Sea: Alvinocaris longirostris Kikuchi & Ohta, 1995 (Alvinocarididae) and Acanthephyra faxoni Calman, 1939 (Acanthephyridae). Specimens of these two species were collected from Jiaolong Cold Seep I, off Guangdong Province, China (depth 1138 m). Alvinocaris longirostris is known to be associated with chemosynthetic community, whereas Acanthephyra faxoni is a bathypelagic inhabitant, of which the occurrence in seep site is merely opportunistic. An identification key to species of Alvinocaris is provided.  PMID:25661601

  19. Coastal sea level response to the tropical cyclonic forcing in the northern Indian Ocean

    NASA Astrophysics Data System (ADS)

    Mehra, P.; Soumya, M.; Vethamony, P.; Vijaykumar, K.; Balakrishnan Nair, T. M.; Agarvadekar, Y.; Jyoti, K.; Sudheesh, K.; Luis, R.; Lobo, S.; Harmalkar, B.

    2015-02-01

    The study examines the observed storm-generated sea level variation due to deep depression (event 1: E1) in the Arabian Sea from 26 November to 1 December 2011 and a cyclonic storm "THANE" (event 2: E2) over the Bay of Bengal during 25-31 December 2011. The sea level and surface meteorological measurements collected during these extreme events exhibit strong synoptic disturbances leading to storm surges of up to 43 cm on the west coast and 29 cm on the east coast of India due to E1 and E2. E1 generated sea level oscillations at the measuring stations on the west coast (Ratnagiri, Verem and Karwar) and east coast (Mandapam and Tuticorin) of India with significant energy bands centred at periods of 92, 43 and 23 min. The storm surge is a well-defined peak with a half-amplitude width of 20, 28 and 26 h at Ratnagiri, Verem and Karwar, respectively. However, on the east coast, the sea level oscillations during Thane were similar to those during calm period except for more energy in bands centred at periods of ~ 100, 42 and 24 min at Gopalpur, Gangavaram and Kakinada, respectively. The residual sea levels from tide gauge stations in Arabian Sea have been identified as Kelvin-type surges propagating northwards at a speed of ~ 6.5 m s-1 with a surge peak of almost constant amplitude. Multi-linear regression analysis shows that the local surface meteorological data (daily mean wind and atmospheric pressure) is able to account for ~ 57 and ~ 69% of daily mean sea level variability along the east and west coasts of India. The remaining part of the variability observed in the sea level may be attributed to local coastal currents and remote forcing.

  20. The diversity of PAH-degrading bacteria in a deep-sea water column above the Southwest Indian Ridge.

    PubMed

    Yuan, Jun; Lai, Qiliang; Sun, Fengqin; Zheng, Tianling; Shao, Zongze

    2015-01-01

    The bacteria involved in organic pollutant degradation in pelagic deep-sea environments are largely unknown. In this report, the diversity of polycyclic aromatic hydrocarbon (PAH)-degrading bacteria was analyzed in deep-sea water on the Southwest Indian Ridge (SWIR). After enrichment with a PAH mixture (phenanthrene, anthracene, fluoranthene, and pyrene), nine bacterial consortia were obtained from depths of 3946-4746 m. While the consortia degraded all four PAHs when supplied in a mixture, when PAHs were tested individually, only phenanthrene supported growth. Thus, degradation of the PAH mixture reflected a cometabolism of anthracene, fluoranthene, and pyrene with phenanthrene. Further, both culture-dependent and independent methods revealed many new bacteria involved in PAH degradation. Specifically, the alpha and gamma subclasses of Proteobacteria were confirmed as the major groups within the communities. Additionally, Actinobacteria, the CFB group and Firmicutes were detected. Denaturing Gradient Gel Electrophoresis (DGGE) analysis showed that bacteria closely affiliated with Alcanivorax, Novosphingobium, and Rhodovulum occurred most frequently in different PAH-degrading consortia. By using general heterotrophic media, 51 bacteria were isolated from the consortia and of these 34 grew with the PAH mixture as a sole carbon source. Of these, isolates most closely related to Alterierythrobacter, Citricella, Erythrobacter, Idiomarina, Lutibacterium, Maricaulis, Marinobacter, Martelella, Pseudidiomarina, Rhodobacter, Roseovarius, Salipiger, Sphingopyxis, and Stappia were found to be PAH degraders. To the best of our knowledge, this is the first time these bacteria have been identified in this context. In summary, this report revealed significant diversity among the PAH-degrading bacteria in the deep-sea water column. These bacteria may play a role in PAH removal in deep-sea environments. PMID:26379634

  1. The diversity of PAH-degrading bacteria in a deep-sea water column above the Southwest Indian Ridge

    PubMed Central

    Yuan, Jun; Lai, Qiliang; Sun, Fengqin; Zheng, Tianling; Shao, Zongze

    2015-01-01

    The bacteria involved in organic pollutant degradation in pelagic deep-sea environments are largely unknown. In this report, the diversity of polycyclic aromatic hydrocarbon (PAH)-degrading bacteria was analyzed in deep-sea water on the Southwest Indian Ridge (SWIR). After enrichment with a PAH mixture (phenanthrene, anthracene, fluoranthene, and pyrene), nine bacterial consortia were obtained from depths of 3946–4746 m. While the consortia degraded all four PAHs when supplied in a mixture, when PAHs were tested individually, only phenanthrene supported growth. Thus, degradation of the PAH mixture reflected a cometabolism of anthracene, fluoranthene, and pyrene with phenanthrene. Further, both culture-dependent and independent methods revealed many new bacteria involved in PAH degradation. Specifically, the alpha and gamma subclasses of Proteobacteria were confirmed as the major groups within the communities. Additionally, Actinobacteria, the CFB group and Firmicutes were detected. Denaturing Gradient Gel Electrophoresis (DGGE) analysis showed that bacteria closely affiliated with Alcanivorax, Novosphingobium, and Rhodovulum occurred most frequently in different PAH-degrading consortia. By using general heterotrophic media, 51 bacteria were isolated from the consortia and of these 34 grew with the PAH mixture as a sole carbon source. Of these, isolates most closely related to Alterierythrobacter, Citricella, Erythrobacter, Idiomarina, Lutibacterium, Maricaulis, Marinobacter, Martelella, Pseudidiomarina, Rhodobacter, Roseovarius, Salipiger, Sphingopyxis, and Stappia were found to be PAH degraders. To the best of our knowledge, this is the first time these bacteria have been identified in this context. In summary, this report revealed significant diversity among the PAH-degrading bacteria in the deep-sea water column. These bacteria may play a role in PAH removal in deep-sea environments. PMID:26379634

  2. The effects of natural iron fertilisation on deep-sea ecology: the Crozet Plateau, Southern Indian Ocean.

    PubMed

    Wolff, George A; Billett, David S M; Bett, Brian J; Holtvoeth, Jens; FitzGeorge-Balfour, Tania; Fisher, Elizabeth H; Cross, Ian; Shannon, Roger; Salter, Ian; Boorman, Ben; King, Nicola J; Jamieson, Alan; Chaillan, Frédéric

    2011-01-01

    The addition of iron to high-nutrient low-chlorophyll (HNLC) oceanic waters stimulates phytoplankton, leading to greater primary production. Large-scale artificial ocean iron fertilization (OIF) has been proposed as a means of mitigating anthropogenic atmospheric CO(2), but its impacts on ocean ecosystems below the photic zone are unknown. Natural OIF, through the addition of iron leached from volcanic islands, has been shown to enhance primary productivity and carbon export and so can be used to study the effects of OIF on life in the ocean. We compared two closely-located deep-sea sites (∼400 km apart and both at ∼4200 m water depth) to the East (naturally iron fertilized; +Fe) and South (HNLC) of the Crozet Islands in the southern Indian Ocean. Our results suggest that long-term geo-engineering of surface oceanic waters via artificial OIF would lead to significant changes in deep-sea ecosystems. We found that the +Fe area had greater supplies of organic matter inputs to the seafloor, including polyunsaturated fatty acid and carotenoid nutrients. The +Fe site also had greater densities and biomasses of large deep-sea animals with lower levels of evenness in community structuring. The species composition was also very different, with the +Fe site showing similarities to eutrophic sites in other ocean basins. Moreover, major differences occurred in the taxa at the +Fe and HNLC sites revealing the crucial role that surface oceanic conditions play in changing and structuring deep-sea benthic communities. PMID:21695118

  3. The Effects of Natural Iron Fertilisation on Deep-Sea Ecology: The Crozet Plateau, Southern Indian Ocean

    PubMed Central

    Wolff, George A.; Billett, David S. M.; Bett, Brian J.; Holtvoeth, Jens; FitzGeorge-Balfour, Tania; Fisher, Elizabeth H.; Cross, Ian; Shannon, Roger; Salter, Ian; Boorman, Ben; King, Nicola J.; Jamieson, Alan; Chaillan, Frédéric

    2011-01-01

    The addition of iron to high-nutrient low-chlorophyll (HNLC) oceanic waters stimulates phytoplankton, leading to greater primary production. Large-scale artificial ocean iron fertilization (OIF) has been proposed as a means of mitigating anthropogenic atmospheric CO2, but its impacts on ocean ecosystems below the photic zone are unknown. Natural OIF, through the addition of iron leached from volcanic islands, has been shown to enhance primary productivity and carbon export and so can be used to study the effects of OIF on life in the ocean. We compared two closely-located deep-sea sites (∼400 km apart and both at ∼4200 m water depth) to the East (naturally iron fertilized; +Fe) and South (HNLC) of the Crozet Islands in the southern Indian Ocean. Our results suggest that long-term geo-engineering of surface oceanic waters via artificial OIF would lead to significant changes in deep-sea ecosystems. We found that the +Fe area had greater supplies of organic matter inputs to the seafloor, including polyunsaturated fatty acid and carotenoid nutrients. The +Fe site also had greater densities and biomasses of large deep-sea animals with lower levels of evenness in community structuring. The species composition was also very different, with the +Fe site showing similarities to eutrophic sites in other ocean basins. Moreover, major differences occurred in the taxa at the +Fe and HNLC sites revealing the crucial role that surface oceanic conditions play in changing and structuring deep-sea benthic communities. PMID:21695118

  4. 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.

  5. Stratigraphic response of a carbonate platform to relative sea level changes: Broken Ridge, southeast Indian Ocean

    SciTech Connect

    Driscoll, N.W.; Weissel, J.K.; Karner, G.D.; Mountain, G.S. )

    1991-04-01

    In contrast to terrigenous margins, the stratigraphic response of carbonate platforms to relative sea level changes is influenced by carbonate productivity, dissolution, and diagenesis. Using seismic reflection and Ocean Drilling Program (ODP) drilling data from Broken Ridge, the authors assess the importance of these processes in controlling the stratigraphic response of a carbonate platform to relative sea level changes. Prior to middle Eocene rifting, Broken Ridge and Kerguelen-Heard Plateau constituted a large carbonate platform. ODP drilling data from the Kerguelen-Heard Plateau and Broken Ridge reveal that the carbonate platform had two major episodes of tectonic uplift. The early Maastrichtian uplift was confined to the southern section of the Kerguelen-Heard Plateau and gently tilted the platform toward the north. The middle Eocene rift-induced uplift affected both Broken Ridge and the northern section of the Kerguelen-Heard Plateau. Watergun seismic reflection and drilling data indicate the following stratigraphic response of the platform to relative sea level changes. (1) prograding clinoforms consisting of carbonate sediments were deposited during a long-term relative sea level rise. (2) Onlapping sequences consisting of carbonate detritus were deposited in the basin during the middle Eocene relative sea level fall. The authors propose that the stratigraphic response of Broken Ridge to the middle Eocene relative sea level fall is consistent with stratigraphic predictions based on terrigenous margins. Stratigraphic models based on terrigenous margins do not account for the increase in sediment supply along carbonate margins during a relative sea level rise, and thus require minor modification in order to predict the development of the prograding clinoforms.

  6. Organochlorine contaminants in tissues of common bottlenose dolphins Tursiops truncatus from the northeastern part of the Adriatic Sea.

    PubMed

    Romanić, S Herceg; Holcer, D; Lazar, B; Klinčić, D; Mackelworth, P; Fortuna, C M

    2014-09-01

    Levels of 24 organochlorine compounds, including toxic mono-ortho PCB congeners, were determined in the organs and tissues (blubber, kidney, lung, muscle, liver, heart) of 13 common bottlenose dolphins (Tursiops truncatus) stranded between 2000 and 2005 in the northern part of the Croatian territorial waters of the Adriatic Sea. Polychlorinated biphenyls (PCBs) were found at higher concentrations in comparison with organochlorine pesticides (OCPs) in all of the analyzed tissues. Sums of six indicator congeners (Σ6PCB) constituted around 50% of the total PCB amount, while PCB-153 and PCB-138 were found to have the highest concentrations. Among the seven investigated OCPs, p,p'-DDE was found at the highest concentrations. In blubber, mean values of 22,048 and 11,310ngg(-1) wet weight were determined for ΣPCB and ΣDDT, respectively. Much lower concentrations were found in muscle samples, followed by similar concentrations in kidneys, liver and heart, while the lowest levels of organochlorine contaminants were found in lungs. The results indicate that p,p'-DDT is still being introduced in the Mediterranean region. PCB concentrations are among the highest found in this region and toxicological assessments indicate that the health of this specie is at high risk. PMID:25151654

  7. 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

  8. 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.

  9. Antibiotics in South Indian coastal sea and farmed prawns (Penaeus monodon).

    PubMed

    Palaniyappan, Venkatesh; Nagalingam, Arun Kumar; Ranganathan, Hari Prasad; Kandhikuppam, Krishnamoorthy Bharathi; Kothandam, Hari Prasath; Vasu, Soumya

    2013-01-01

    Sulphonamides and chloramphenicol antibiotics were analysed by using liquid chromatography-tandem mass spectrometry (LC-MS/MS) in sea and farmed prawn (Penaeus monodon) samples obtained from the coastal region of southern India during 2011-2012. Average recoveries were 77-99% and precision was between 1% and 8%. The results revealed that in sea prawn samples neither of the two antibiotics was detected, but in farmed samples from coastal Andhra Pradesh some sulphonamides were detected in a concentration range greater than the maximum residual limit as set by Council Directive 2377/90 EC. PMID:24779904

  10. Disintegration of a marine-based ice stream - evidence from the Norwegian Channel, north-eastern North Sea

    NASA Astrophysics Data System (ADS)

    Morén, Björn M.; Petter Sejrup, Hans; Hjelstuen, Berit O.; Haflidason, Haflidi; Schäuble, Cathrina; Borge, Marianne

    2014-05-01

    The Norwegian Channel Ice Stream repeatedly drained large part of the Fennoscandian Ice Sheet through Mid and Late Pleistocene glacial stages. During parts of Marine Isotope Stages 2 and 3, glacial ice from Fennoscandia and the British Isles coalesced in the central North Sea and the Norwegian Channel Ice Stream reached the shelf edge on multiple occasions. Through the last decades a large amount of acoustic and sediment core data have been collected from the Norwegian Channel, providing a good background for studies focussing on stability- and development-controlling parameters for marine-based ice streams, the retreat rate of the Norwegian Channel Ice Stream, and the behaviour of the Fennoscandian Ice Sheet. Further, this improved understanding can be used to develop more accurate numerical climate models and models which can be used to model ice-sheet behaviour of the past as well as the future. This study presents new acoustic records and data from sediment cores which contribute to a better understanding of the retreat pattern and the retreat rate of the last ice stream that occupied the Norwegian Channel. From bathymetric and TOPAS seismic data, mega-scale glacial lineations, grounding-zone wedges, and end moraines have been mapped, thereby allowing us to reconstruct the pro- and subglacial conditions at the time of the creation of these landforms. It is concluded that the whole Norwegian Channel was deglaciated in just over 1 000 years and that for most of this time the ice margin was located at positions reflected by depositional grounding-zone wedges. Further work will explore the influence of channel shape and feeding of ice from western Norwegian fjords on this retreat pattern through numerical modelling.

  11. Mechanisms of Summertime Subtropical Southern Indian Ocean Sea Surface Temperature Variability: The Importance of Atmospheric Water Vapor Transport

    NASA Astrophysics Data System (ADS)

    Chiodi, A. M.; Harrison, D. E.

    2006-12-01

    It is well known that some warm season subtropical Indian Ocean sea surface temperature (SST) variability correlates with rainfall over certain regions of Africa that depend on rainfall for their economic well being. This SST variability is known to have a distinctive basin-scale pattern that is also observed in latent heat flux variability. Recent studies have determined that this SST variability is at least partially driven by latent heat flux, but the processes that create this latent heat flux variability have not been fully described. Previously, it has been hypothesized that wind speed variations drive this latent heat flux variability. Here, the mechanism that drives this heat flux/SST variability is determined from analyses of operational air-sea fluxes, ocean mixed layer modeling and simple atmospheric boundary layer physics. Results confirm that this SST variability is predominantly driven by latent heat flux variability, but show that this latent heat flux variability is mainly driven by near surface humidity anomalies, rather than wind speed anomalies. Results also show that these humidity anomalies are fundamentally driven by the advection of the climatological humidity field by near surface meridional wind anomalies. It is shown that the pertinent wind anomalies occur when the subtropical atmospheric anticyclone is preferentially located to one side of the basin. Although the timescale of air-sea interaction is not an intrinsic part of the mechanism described here, it is notable that the details of this process is often obscured in seasonal or longer term averages. For instance, the magnitudes of the monthly latent heat anomalies described here are up to an order of magnitude larger than the multi-seasonal anomalies that have previously been reported to be associated with these phenomena. The mechanism described here implies that Atmospheric Model Intercomparison Project (AMIP) style models, such as those that may be used for rainfall prediction, will

  12. Structural Evolution of the India-Arabia Plate Boundary from Miocene to Present-Day (NW Indian Ocean) and Comparison with the Dead Sea Fault (Eastern Mediterranean Sea).

    NASA Astrophysics Data System (ADS)

    Rodriguez, M.; Huchon, P.; Chamot Rooke, N.; Fournier, M.; Delescluse, M.; Ben Avraham, Z.; Ten Brink, U. S.

    2014-12-01

    Arabia is bounded by the Dead Sea Transform (DST) to the west and by the Owen Fracture Zone (OFZ) to the east. These present-day major strike-slip fault systems activated during the Plio-Pleistocene, which contrasts with the age of inception of strike-slip motion, assumed to begin around 13-18 Ma for the DST and around 20 Ma at the edge of the Owen-Murray Ridge (OMR) for the India-Arabia plate boundary. This discrepancy between the age of the active strike-slip systems and the age of inception of strike-slip motion raises the question of the kinematic driver for the transition between successive generations of strike-slip faults. Using a recent mutibeam and seismic dataset crossing the OFZ and the OMR, we provide a new geodynamic framework for the Miocene to present-day structural evolution of the India-Arabia plate boundary, and highlight some similarities with the structural evolution of the DST. We first document a Late Miocene episode of uplift of the OMR uplift along the Miocene India-Arabia plate boundary. The onset of this uplift is coeval with a plate reorganization event marked by the onset of intra-plate deformation in the Central Indian Ocean. The OFZ emplaced around 3 Ma, with major pull-apart basins opening (20°N Basin, Dalrymple Trough) dated at 2.4 Ma by far-field correlation with ODP Sites. The opening of pull-apart basins is coeval with the last structural reorganization of the Makran accretionnary wedge, marked by the regional M-unconformity, and with a major intensification of the Indian monsoon. A Late Miocene episode of folding is also recognized at the Lebanon ranges prior to the onset of the present-day DST, which occurred in the Late Pliocene-Early Pleistocene. The similarities between the geological history of the India-Arabia plate boundary and the DST in the Late Miocene and the Late Pliocene-Early Pleistocene suggest that both plate boundaries recorded the same kinematic changes. Late Miocene (i.e. Tortonian) deformation is widely

  13. Insights into deep-sea sediment fungal communities from the East Indian Ocean using targeted environmental sequencing combined with traditional cultivation.

    PubMed

    Zhang, Xiao-yong; Tang, Gui-ling; Xu, Xin-ya; Nong, Xu-hua; Qi, Shu-hua

    2014-01-01

    The fungal diversity in deep-sea environments has recently gained an increasing amount attention. Our knowledge and understanding of the true fungal diversity and the role it plays in deep-sea environments, however, is still limited. We investigated the fungal community structure in five sediments from a depth of ∼ 4000 m in the East India Ocean using a combination of targeted environmental sequencing and traditional cultivation. This approach resulted in the recovery of a total of 45 fungal operational taxonomic units (OTUs) and 20 culturable fungal phylotypes. This finding indicates that there is a great amount of fungal diversity in the deep-sea sediments collected in the East Indian Ocean. Three fungal OTUs and one culturable phylotype demonstrated high divergence (89%-97%) from the existing sequences in the GenBank. Moreover, 44.4% fungal OTUs and 30% culturable fungal phylotypes are new reports for deep-sea sediments. These results suggest that the deep-sea sediments from the East India Ocean can serve as habitats for new fungal communities compared with other deep-sea environments. In addition, different fungal community could be detected when using targeted environmental sequencing compared with traditional cultivation in this study, which suggests that a combination of targeted environmental sequencing or traditional cultivation alone. This study is the first to report new insights into the fungal communities in deep-sea sediments environmental sequencing and traditional cultivation will generate a more diverse fungal community in deep-sea environments than using either from the East Indian Ocean, which increases our knowledge and understanding of the fungal diversity in deep-sea environments. PMID:25272044

  14. Insights into Deep-Sea Sediment Fungal Communities from the East Indian Ocean Using Targeted Environmental Sequencing Combined with Traditional Cultivation

    PubMed Central

    Zhang, Xiao-yong; Tang, Gui-ling; Xu, Xin-ya; Nong, Xu-hua; Qi, Shu-Hua

    2014-01-01

    The fungal diversity in deep-sea environments has recently gained an increasing amount attention. Our knowledge and understanding of the true fungal diversity and the role it plays in deep-sea environments, however, is still limited. We investigated the fungal community structure in five sediments from a depth of ∼4000 m in the East India Ocean using a combination of targeted environmental sequencing and traditional cultivation. This approach resulted in the recovery of a total of 45 fungal operational taxonomic units (OTUs) and 20 culturable fungal phylotypes. This finding indicates that there is a great amount of fungal diversity in the deep-sea sediments collected in the East Indian Ocean. Three fungal OTUs and one culturable phylotype demonstrated high divergence (89%–97%) from the existing sequences in the GenBank. Moreover, 44.4% fungal OTUs and 30% culturable fungal phylotypes are new reports for deep-sea sediments. These results suggest that the deep-sea sediments from the East India Ocean can serve as habitats for new fungal communities compared with other deep-sea environments. In addition, different fungal community could be detected when using targeted environmental sequencing compared with traditional cultivation in this study, which suggests that a combination of targeted environmental sequencing and traditional cultivation will generate a more diverse fungal community in deep-sea environments than using either targeted environmental sequencing or traditional cultivation alone. This study is the first to report new insights into the fungal communities in deep-sea sediments from the East Indian Ocean, which increases our knowledge and understanding of the fungal diversity in deep-sea environments. PMID:25272044

  15. Recent summer precipitation trends in the Greater Horn of Africa and the emerging role of Indian Ocean sea surface temperature

    NASA Astrophysics Data System (ADS)

    Williams, A. Park; Funk, Chris; Michaelsen, Joel; Rauscher, Sara A.; Robertson, Iain; Wils, Tommy H. G.; Koprowski, Marcin; Eshetu, Zewdu; Loader, Neil J.

    2012-11-01

    We utilize a variety of climate datasets to examine impacts of two mechanisms on precipitation in the Greater Horn of Africa (GHA) during northern-hemisphere summer. First, surface-pressure gradients draw moist air toward the GHA from the tropical Atlantic Ocean and Congo Basin. Variability of the strength of these gradients strongly influences GHA precipitation totals and accounts for important phenomena such as the 1960s-1980s rainfall decline and devastating 1984 drought. Following the 1980s, precipitation variability became increasingly influenced by the southern tropical Indian Ocean (STIO) region. Within this region, increases in sea-surface temperature, evaporation, and precipitation are linked with increased exports of dry mid-tropospheric air from the STIO region toward the GHA. Convergence of dry air above the GHA reduces local convection and precipitation. It also produces a clockwise circulation response near the ground that reduces moisture transports from the Congo Basin. Because precipitation originating in the Congo Basin has a unique isotopic signature, records of moisture transports from the Congo Basin may be preserved in the isotopic composition of annual tree rings in the Ethiopian Highlands. A negative trend in tree-ring oxygen-18 during the past half century suggests a decline in the proportion of precipitation originating from the Congo Basin. This trend may not be part of a natural cycle that will soon rebound because climate models characterize Indian Ocean warming as a principal signature of greenhouse-gas induced climate change. We therefore expect surface warming in the STIO region to continue to negatively impact GHA precipitation during northern-hemisphere summer.

  16. Predicting East African spring droughts using Pacific and Indian Ocean sea surface temperature indices

    USGS Publications Warehouse

    Funk, Christopher C.; Hoell, Andrew; Shukla, Shraddhanand; Blade, Ileana; Liebmann, Brant; Roberts, Jason B.; Robertson, Franklin R.

    2014-01-01

    In southern Ethiopia, Eastern Kenya, and southern Somalia poor boreal spring rains in 1999, 2000, 2004, 2007, 2008, 2009 and 2011 contributed to severe food insecurity and high levels of malnutrition. Predicting rainfall deficits in this region on seasonal and decadal time frames can help decision makers support disaster risk reduction while guiding climate-smart adaptation and agricultural development. Building on recent research that links more frequent droughts to a stronger Walker Circulation, warming in the Indo-Pacific warm pool, and an increased western Pacific sea surface temperature (SST) gradient, we explore the dominant modes of East African rainfall variability, links between these modes and sea surface temperatures, and a simple index-based monitoring-prediction system suitable for drought early warning.

  17. Structure of the lithosphere of the northeastern part of the Indian Ocean according to results of two-dimensional structural-density modeling

    NASA Astrophysics Data System (ADS)

    Bulychev, A. A.; Gilod, D. A.; Dubinin, E. P.

    2016-05-01

    From a gravitational field analysis, the lithosphere was regionalized and a structural schematic map of the eastern part of the Indian Ocean was compiled. The area adjacent to the western margin of Australia was studied. The region is characterized by a complex lithospheric structure. It includes heterogeneous blocks of varying age, framed by structures with different morphological and geophysical expression and varying genesis. To clarify the peculiarities of tectonic structures of various genetic types, structural-density modeling was performed. This made it possible to establish certain gravimetric indicators characteristic of structures of various genesis.

  18. Can large scale surface circulation changes modulate the sea surface warming pattern in the Tropical Indian Ocean?

    NASA Astrophysics Data System (ADS)

    Rahul, S.; Gnanaseelan, C.

    2016-06-01

    The increased rate of Tropical Indian Ocean (TIO) surface warming has gained a lot of attention in the recent years mainly due to its regional climatic impacts. The processes associated with this increased surface warming is highly complex and none of the mechanisms in the past studies could comprehend the important features associated with this warming such as the negative trends in surface net heat fluxes and the decreasing temperature trends at thermocline level. In this work we studied a previously unexplored aspect, the changes in large scale surface circulation pattern modulating the surface warming pattern over TIO. We use ocean reanalysis datasets and a suit of Ocean General Circulation Model (OGCM) experiments to address this problem. Both reanalysis and OGCM reveal strengthening large scale surface circulation pattern in the recent years. The most striking feature is the intensification of cyclonic gyre circulation around the thermocline ridge in the southwestern TIO. The surface circulation change in TIO is mainly associated with the surface wind changes and the geostrophic response to sea surface height decrease in the western/southwestern TIO. The surface wind trends closely correspond to SST warming pattern. The strengthening mean westerlies over the equatorial region are conducive to convergence in the central and divergence in the western equatorial Indian Ocean (IO) resulting central warming and western cooling. The resulting east west SST gradient further enhances the equatorial westerlies. This positive feedback mechanism supports strengthening of the observed SST trends in the equatorial Indian Ocean. The cooling induced by the enhanced upwelling in the west is compensated to a large extent by warming due to reduction in mixed layer depth, thereby keeping the surface temperature trends in the west to weak positive values. The OGCM experiments showed that the wind induced circulation changes redistribute the excess heat received in the western

  19. Physical and chemical properties of water and sediments, Grand Portage and Wauswaugoning Bays, Lake Superior, Grand Portage Indian Reservation, northeastern Minnesota, 1993-96

    USGS Publications Warehouse

    Ruhl, J.F.

    1997-01-01

    This report is a compilation of data on the physical and chemical properties of water and sediments in Grand Portage and Wauswaugoning Bays of Lake Superior along the shoreline of the Grand Portage Indian Reservation. The data were collected during 1993-96 by the U.S. Geological Survey in cooperation with the Grand Portage Indian Reservation. The data include: (1) temperature, pH, and specific conductance measurements and dissolved oxygen concentrations; (2) Secchi disk transparency, alkalinity, and turbidity measurements; (3) fecal Coliform and fecal Streptococcal bacteria colony counts (per 100 milliliters of sample water); (4) major and minor ion, nutrient, and trace-metal concentrations; (5) dissolved and suspended residue concentrations; (6) pesticide, phenol, and asbestos concentrations; (7) suspended sediment trace-metal concentrations; and (8) bottom sediment trace-metal concentrations. Water samples were collected from nine sites; suspended and bottom sediment samples were collected from five sites. The data in this report can be used to evaluate present water-quality conditions and as a reference to monitor potential long-term changes in these conditions.

  20. A cold pool formation in the Lakshadweep Sea during Indian summer monsoon

    NASA Astrophysics Data System (ADS)

    Zacharia, Johnson; Rajan, Chungath Kuttan; Jayaram, Chiranjivi

    2012-06-01

    In Lakshadweep Sea, the distribution of observed sea surface temperature (SST) during summer monsoon season (June-September) shows the presence of a distinct cold pool (SST < 27°C). Available satellite measurements and assimilated datasets are utilized to investigate the characteristics and mechanisms that govern the genesis and evolution of this cold pool. It is located in the grid 8° N-10° N/74° E-76° E, with a diameter of about 200 km, centered approximately at 9° N/75° E off the southwest coast of India. This cold pool, which we call as the Lakshadweep cold pool (LCP), forms invariably during the fifth pentad of June as a small cooling within the cold surface waters advected northward along the southwest coast of India from the Arabian Sea Mini Cold Pool. With the progress of the season, LCP intensifies, spread radially outwards and shows a westward spread during late July. Maximum intensity and radial spread are attained during July. By the end of August, LCP extends northward along the coast up to 13° N, and by September, it gets completely dissipated. Within the LCP, the thermocline exhibits pronounced shoaling compared to the adjacent regions. The intensity, duration, and spread of LCP showed annual variations in each summer monsoon during 1998-2005 and owes its origin to upwelling produced by uplift of poleward undercurrent induced by an elevated bathymetry in the presence of a seamount. The mechanism for the intensification is thought to be due to the combined action of Ekman pumping due to positive wind stress curl, eddy-induced upwelling due to the Lakshadweep low, and the intensification of the poleward undercurrent during the season. West- and northward spreads of LCP are attributed to the westward movement of Lakshadweep Low and the northerly spreading and intensification of positive wind stress curl, respectively. The mechanisms that govern this phenomenon are thoroughly examined.

  1. Processing effects on the composition of sea buckthorn juice from Hippophae rhamnoides L. Cv. Indian Summer.

    PubMed

    Beveridge, T; Harrison, J E; Drover, J

    2002-01-01

    Sea buckthorn juice is one product that can be derived from the sea buckthorn berry, a new alternative crop for the Canadian western provinces. Fresh pressed juice separates into three phases when allowed to stand overnight in the refrigerator: an upper cream phase, juice in the middle portion, and a sediment at the bottom. Enzymatic hydrolysis with commercial, broad spectrum carbohydrate hydrolyzing enzyme preparations reduced the juice viscosity, assisted juice separation, and provided an opalescent juice. Soluble solids averaged 10.2 degrees Brix, pH averaged 3.13, ascorbic acid averaged 174.2 mg/100 mL, and titratable acidity averaged 1.97% as malic acid all determined on centrifuged (10 000 rpm, 15 min) juice. Soluble sugars included glucose, fructose, and an unidentified component that was not sucrose or other common soluble monomeric or dimeric sugar. Quinic acid was quantitatively most important, while malic was next, and oxalic, citric, and tartaric acids were minor components. Washing berries by dipping reduced soluble solids (degrees Brix) in juice suggesting uptake of wash water. PMID:11754553

  2. Fulvimarina manganoxydans sp. nov., isolated from a deep-sea hydrothermal plume in the south-west Indian Ocean.

    PubMed

    Ren, Fei; Zhang, Limin; Song, Lei; Xu, Shiyao; Xi, Lijun; Huang, Li; Huang, Ying; Dai, Xin

    2014-08-01

    An aerobic, Mn(II)-oxidizing, Gram-negative bacterium, strain 8047(T), was isolated from a deep-sea hydrothermal vent plume in the south-west Indian Ocean. The strain was rod-shaped and motile with a terminal flagellum, and formed yellowish colonies. It produced catalase and oxidase, hydrolysed gelatin and reduced nitrate. 16S rRNA gene sequence analysis showed that strain 8047(T) belonged to the order Rhizobiales of the class Alphaproteobacteria, and was phylogenetically most closely related to the genus Fulvimarina, sharing 94.4% sequence identity with the type strain of the type species. The taxonomic affiliation of strain 8047(T) was supported by phylogenetic analysis of four additional housekeeping genes, gyrB, recA, rpoC and rpoB. The predominant respiratory lipoquinone of strain 8047(T) was Q-10, the major fatty acid was C(18 : 1)ω7c and the DNA G+C content was 61.7 mol%. On the basis of the phenotypic and genotypic characteristics determined in this study, strain 8047(T) represents a novel species within the genus Fulvimarina, for which the name Fulvimarina manganoxydans sp. nov. is proposed. The type strain is strain 8047(T) ( = CGMCC1.10972(T) = JCM 18890(T)). PMID:24854008

  3. The Relation between Indian Monsoon Rainfall, the Southern Oscillation, and Hemispheric Air and Sea Temperature: 1884-1984.

    NASA Astrophysics Data System (ADS)

    Elliott, W. P.; Angell, J. K.

    1987-08-01

    Correlations between the June-September Indian monsoon rainfall and Santiago minus Darwin pressure, Tahiti minus Darwin pressure, and Wright's Southern Oscillation index, as well as the individual station pressure deviations themselves, show that the monsoon rainfall anticipates the Southern Oscillation Indices and the individual pressure deviations with the exception of the pressure at Santiago. Monsoon rainfall is also negatively correlated with sea surface temperatures in the eastern equatorial Pacific one to two seasons later. The correlations suggest that above average monsoon rainfall is associated with below average Southern Hemisphere temperatures two to three seasons later, whereas above average Northern Hemisphere winter temperatures-particularly continental temperatures-anticipate above average rainfall. The correlations with hemispheric temperatures are significant only since about 1947, however. A strong negative correlation (0.64) between the seasonal change in Darwin's pressure deviation from December-February to March-May prior to the monsoon, and monsoon rainfall is found in the period 1947-84, but only weakly in the period before 1947.

  4. Sedimentary pigments and nature of organic matter within the oxygen minimum zone (OMZ) of the Eastern Arabian Sea (Indian margin)

    NASA Astrophysics Data System (ADS)

    Rasiq, K. T.; Kurian, S.; Karapurkar, S. G.; Naqvi, S. W. A.

    2016-07-01

    Sedimentary pigments, carbon and nitrogen content and their stable isotopes were studied in three short cores collected from the oxygen minimum zone (OMZ) of the Eastern Arabian Sea (EAS). Nine pigments including chlorophyll a and their degradation products were quantified using High Performance Liquid Chromatography (HPLC). Astaxanthin followed by canthaxanthin and zeaxanthin were the major carotenoids detected in these cores. The total pigment concentration was high in the core collected from 500 m water depth (6.5 μgg-1) followed by 800 m (1.7 μgg-1) and 1100 m (1.1 μgg-1) depths respectively. The organic carbon did not have considerable control on sedimentary pigments preservation. Pigment degradation was comparatively high in the core collected from the 800 m site which depended not only the bottom dissolved oxygen levels, but also on the faunal activity. As reported earlier, the bottom water dissolved oxygen and presence of fauna have good control on the organic carbon accumulation and preservation at Indian margin OMZ sediments. The C/N ratios and δ13C values for all the cores conclude the marine origin of organic matter and δ15N profiles revealed signature of upwelling associated denitrification within the water column.

  5. Signatures of Indian Ocean Dipole and El Niño-Southern Oscillation events in sea level variations in the Bay of Bengal

    NASA Astrophysics Data System (ADS)

    Aparna, S. G.; McCreary, J. P.; Shankar, D.; Vinayachandran, P. N.

    2012-10-01

    We investigate the impact of the Indian Ocean Dipole (IOD) and El Niño and the Southern Oscillation (ENSO) on sea level variations in the North Indian Ocean during 1957-2008. Using tide-gauge and altimeter data, we show that IOD and ENSO leave characteristic signatures in the sea level anomalies (SLAs) in the Bay of Bengal. During a positive IOD event, negative SLAs are observed during April-December, with the SLAs decreasing continuously to a peak during September-November. During El Niño, negative SLAs are observed twice (April-December and November-July), with a relaxation between the two peaks. SLA signatures during negative IOD and La Niña events are much weaker. We use a linear, continuously stratified model of the Indian Ocean to simulate their sea level patterns of IOD and ENSO events. We then separate solutions into parts that correspond to specific processes: coastal alongshore winds, remote forcing from the equator via reflected Rossby waves, and direct forcing by interior winds within the bay. During pure IOD events, the SLAs are forced both from the equator and by direct wind forcing. During ENSO events, they are primarily equatorially forced, with only a minor contribution from direct wind forcing. Using a lead/lag covariance analysis between the Niño-3.4 SST index and Indian Ocean wind stress, we derive a composite wind field for a typical El Niño event: the resulting solution has two negative SLA peaks. The IOD and ENSO signatures are not evident off the west coast of India.

  6. Helicopter electromagnetic and magnetic survey maps and data, East Poplar Oil Field area, August 2004, Fort Peck Indian Reservation, northeastern Montana

    USGS Publications Warehouse

    Smith, Bruce D.; Thamke, Joanna N.; Cain, Michael J.; Tyrrell, Christa; Hill, Patricia L.

    2006-01-01

    This report is a data release for a helicopter electromagnetic and magnetic survey that was conducted during August 2004 in a 275-square-kilometer area that includes the East Poplar oil field on the Fort Peck Indian Reservation. The electromagnetic equipment consisted of six different coil-pair orientations that measured resistivity at separate frequencies from about 400 hertz to about 140,000 hertz. The electromagnetic resistivity data were converted to six electrical conductivity grids, each representing different approximate depths of investigation. The range of subsurface investigation is comparable to the depth of shallow aquifers. Areas of high conductivity in shallow aquifers in the East Poplar oil field area are being delineated by the U.S. Geological Survey, in cooperation with the Fort Peck Assiniboine and Sioux Tribes, in order to map areas of saline-water plumes. Ground electromagnetic methods were first used during the early 1990s to delineate more than 31 square kilometers of high conductivity saline-water plumes in a portion of the East Poplar oil field area. In the 10 years since the first delineation, the quality of water from some wells completed in the shallow aquifers in the East Poplar oil field changed markedly. The extent of saline-water plumes in 2004 likely differs from that delineated in the early 1990s. The geophysical and hydrologic information from U.S. Geological Survey studies is being used by resource managers to develop ground-water resource plans for the area.

  7. Qualitative and quantitative saponin contents in five sea cucumbers from the Indian ocean.

    PubMed

    Van Dyck, Séverine; Gerbaux, Pascal; Flammang, Patrick

    2010-01-01

    To avoid predation, holothuroids produce feeding-deterrent molecules in their body wall and viscera, the so-called saponins. Five tropical sea cucumber species of the family Holothuriidae were investigated in order to study their saponin content in two different organs, the body wall and the Cuvierian tubules. Mass spectrometry techniques (MALDI- and ESI-MS) were used to detect and analyze saponins. The smallest number of saponins was observed in Holothuria atra, which contained a total of four congeners, followed by Holothuria leucospilota, Pearsonothuria graeffei and Actinopyga echinites with six, eight and ten congeners, respectively. Bohadschia subrubra revealed the highest saponin diversity (19 congeners). Saponin mixtures also varied between the two body compartments within a given animal. A semi-quantitative approach completed these results and showed that a high diversity of saponins is not particularly correlated to a high saponin concentration. Although the complexity of the saponin mixtures described makes the elucidation of their respective biological roles difficult, the comparisons between species and between body compartments give some clues about how these molecules may act as predator repellents. PMID:20161976

  8. Inter-decadal changes in the East Asian summer monsoon and associations with sea surface temperature anomaly in the South Indian Ocean

    NASA Astrophysics Data System (ADS)

    Zhang, Haiyan; Wen, Zhiping; Wu, Renguang; Chen, Zesheng; Guo, Yuanyuan

    2016-04-01

    Previous studies have revealed inter-decadal changes in the East Asian summer monsoon (EASM) that occurred around the late 1970s and early 1990s, respectively. The present study compares characteristics of these two changes and analyzes plausible influences of the South Indian Ocean (SIO) sea surface temperature (SST) change. The two changes share pronounced common features, characterized by an equivalent barotropic circulation anomaly over northern East Asia and a meridional vertical overturning circulation over the tropical region. Meanwhile, they display some distinct characteristics, especially over the tropics. The circumfluent anomalies are more robust for the first change than for the second one. Related amplitude asymmetry is partly attributed to a weakening trend in the EASM. Moreover, SST change in the SIO, featuring a decadal warming since the 1980s and a cooling after 1993, may contribute to both of these inter-decadal changes. Cold SST anomaly induces anomalous mid-tropospheric descent over the western SIO and ascent extending from the eastern SIO to western Australia and over the equatorial Indian Ocean. The accompanying upper-tropospheric divergent flows from western Australia and equatorial Indian Ocean to the Philippines lead to anomalous descent and an anomalous lower-tropospheric anticyclone over the South China Sea-Philippines. Warm SST anomaly induces opposite changes in above regions. The possible influence of SST anomaly in the SIO is further confirmed by numerical experiments.

  9. Diversity, Biogeography, and Biodegradation Potential of Actinobacteria in the Deep-Sea Sediments along the Southwest Indian Ridge

    PubMed Central

    Chen, Ping; Zhang, Limin; Guo, Xiaoxuan; Dai, Xin; Liu, Li; Xi, Lijun; Wang, Jian; Song, Lei; Wang, Yuezhu; Zhu, Yaxin; Huang, Li; Huang, Ying

    2016-01-01

    The phylum Actinobacteria has been reported to be common or even abundant in deep marine sediments, however, knowledge about the diversity, distribution, and function of actinobacteria is limited. In this study, actinobacterial diversity in the deep sea along the Southwest Indian Ridge (SWIR) was investigated using both 16S rRNA gene pyrosequencing and culture-based methods. The samples were collected at depths of 1662–4000 m below water surface. Actinobacterial sequences represented 1.2–9.1% of all microbial 16S rRNA gene amplicon sequences in each sample. A total of 5 actinobacterial classes, 17 orders, 28 families, and 52 genera were detected by pyrosequencing, dominated by the classes Acidimicrobiia and Actinobacteria. Differences in actinobacterial community compositions were found among the samples. The community structure showed significant correlations to geochemical factors, notably pH, calcium, total organic carbon, total phosphorus, and total nitrogen, rather than to spatial distance at the scale of the investigation. In addition, 176 strains of the Actinobacteria class, belonging to 9 known orders, 18 families, and 29 genera, were isolated. Among these cultivated taxa, 8 orders, 13 families, and 15 genera were also recovered by pyrosequencing. At a 97% 16S rRNA gene sequence similarity, the pyrosequencing data encompassed 77.3% of the isolates but the isolates represented only 10.3% of the actinobacterial reads. Phylogenetic analysis of all the representative actinobacterial sequences and isolates indicated that at least four new orders within the phylum Actinobacteria were detected by pyrosequencing. More than half of the isolates spanning 23 genera and all samples demonstrated activity in the degradation of refractory organics, including polycyclic aromatic hydrocarbons and polysaccharides, suggesting their potential ecological functions and biotechnological applications for carbon recycling. PMID:27621725

  10. Diversity, Biogeography, and Biodegradation Potential of Actinobacteria in the Deep-Sea Sediments along the Southwest Indian Ridge.

    PubMed

    Chen, Ping; Zhang, Limin; Guo, Xiaoxuan; Dai, Xin; Liu, Li; Xi, Lijun; Wang, Jian; Song, Lei; Wang, Yuezhu; Zhu, Yaxin; Huang, Li; Huang, Ying

    2016-01-01

    The phylum Actinobacteria has been reported to be common or even abundant in deep marine sediments, however, knowledge about the diversity, distribution, and function of actinobacteria is limited. In this study, actinobacterial diversity in the deep sea along the Southwest Indian Ridge (SWIR) was investigated using both 16S rRNA gene pyrosequencing and culture-based methods. The samples were collected at depths of 1662-4000 m below water surface. Actinobacterial sequences represented 1.2-9.1% of all microbial 16S rRNA gene amplicon sequences in each sample. A total of 5 actinobacterial classes, 17 orders, 28 families, and 52 genera were detected by pyrosequencing, dominated by the classes Acidimicrobiia and Actinobacteria. Differences in actinobacterial community compositions were found among the samples. The community structure showed significant correlations to geochemical factors, notably pH, calcium, total organic carbon, total phosphorus, and total nitrogen, rather than to spatial distance at the scale of the investigation. In addition, 176 strains of the Actinobacteria class, belonging to 9 known orders, 18 families, and 29 genera, were isolated. Among these cultivated taxa, 8 orders, 13 families, and 15 genera were also recovered by pyrosequencing. At a 97% 16S rRNA gene sequence similarity, the pyrosequencing data encompassed 77.3% of the isolates but the isolates represented only 10.3% of the actinobacterial reads. Phylogenetic analysis of all the representative actinobacterial sequences and isolates indicated that at least four new orders within the phylum Actinobacteria were detected by pyrosequencing. More than half of the isolates spanning 23 genera and all samples demonstrated activity in the degradation of refractory organics, including polycyclic aromatic hydrocarbons and polysaccharides, suggesting their potential ecological functions and biotechnological applications for carbon recycling. PMID:27621725

  11. Living (Rose-Bengal-stained) benthic foraminiferal faunas along a strong bottom-water oxygen gradient on the Indian margin (Arabian Sea)

    NASA Astrophysics Data System (ADS)

    Caulle, C.; Mojtahid, M.; Gooday, A. J.; Jorissen, F. J.; Kitazato, H.

    2015-08-01

    Rose-Bengal-stained foraminiferal assemblages (> 150 μm) were analysed along a five-station bathymetric transect across the core and the lower part of the oxygen minimum zone (OMZ) on the Indian margin of the Arabian Sea. Sediment cores were collected using the manned submersible Shinkai 6500 during the RV Yokosuka cruise YK08-11 in the post-monsoon season (October 2008) at water depths ranging from 535 to 2000 m, along a gradient from almost anoxic to well-oxygenated (0.3 to 108 μM) bottom waters. Stained benthic foraminifera were investigated from two different size fractions (150-300 μm and > 300 μm). Stained foraminiferal densities were very high in the core of the OMZ (at 535 and 649 m) and decreased at deeper sites. The faunas (> 150 μm) were dominated (40-80 %) by non-calcareous taxa at all stations. These were mainly species of Reophax and Lagenammina but also included delicate monothalamous taxa (organic-walled "allogromiids", agglutinated saccamminids, psammosphaerids and tubular forms). These new data from the Indian margin are compared to previous studies from the Murray Ridge, the Pakistan margin and the Oman margin. The fact that similar species were found at sites with comparable bottom-water oxygen concentrations but with very different surface water productivity suggests that, within the strongly developed Arabian Sea OMZ, bottom-water oxygen concentration, and not the organic flux to the sea floor, is the main factor controlling the species composition of the foraminiferal communities. Several foraminiferal species (e.g. Praeglobobulimina sp. 1, Ammodiscus sp. 1, Bolivina aff. dilatata) were confined to the core of the OMZ. These species are presently known only from the Arabian Sea. Because of their association with extremely low oxygen concentrations, these species may be good markers for very low oxygen concentrations, and could be used to reconstruct past OMZ variability in the Arabian Sea.

  12. Living (Rose Bengal stained) benthic foraminiferal faunas along a strong bottom-water oxygen gradient on the Indian margin (Arabian Sea)

    NASA Astrophysics Data System (ADS)

    Caulle, C.; Mojtahid, M.; Gooday, A. J.; Jorissen, F. J.; Kitazato, H.

    2015-02-01

    Rose Bengal stained foraminiferal assemblages were analysed along a five-station bathymetric transect across the core and the lower part of the oxygen minimum zone (OMZ) on the Indian margin of the Arabian Sea. Sediment cores were collected using the manned submersible Shinkai 6500 during RV Yokosuka cruise YK08-11 in the post-monsoon season (October 2008) at water depths ranging from 535 to 2000 m, along a gradient from almost anoxic to well-oxygenated (0.3 to 108 μM) bottom waters. Stained foraminiferal densities were very high in the OMZ core (535 m) and decreased with depth. The faunas were dominated (40-80%) by non-calcareous taxa at all stations. These were mainly species of Reophax and Lagenammina but also included delicate monothalamous taxa (organic-walled "allogromiids", agglutinated saccamminids, psammosphaerids and tubular forms). These new data from the Indian margin are compared to previous studies from the Murray Ridge, the Pakistan margin and the Oman margin. The fact that similar species were found at sites with comparable bottom-water oxygen concentrations but with very different surface water productivity suggests that, within the strongly developed Arabian Sea OMZ, bottom-water oxygen concentration, and not the organic flux to the sea floor, is the main factor controlling the species composition of the foraminiferal communities. Several foraminiferal species (e.g. Praeglobobulimina sp. 1, Ammodiscus sp. 1, Bolivina aff. dilatata) were confined to the core of the OMZ and are presently known only from the Arabian Sea. Because of their association with extremely low-oxygen concentration, these species may prove to be good indicators of past OMZ variability in the Arabian Sea.

  13. The zonal movement of the Indian-East Asian summer monsoon interface in relation to the land-sea thermal contrast anomaly over East Asia

    NASA Astrophysics Data System (ADS)

    Tao, Yun; Cao, Jie; Lan, Guangdong; Su, Qin

    2016-05-01

    Based on atmospheric circulation reanalysis, global gridded precipitation, and outgoing longwave radiation datasets, this study reveals the physical process through which the land-sea thermal contrast over East Asia interrelates with the variability of the interface between the Indian summer monsoon and East Asian summer monsoon (IIE). The results indicate that the release of latent heating exerted by the low-frequency variability of anomalous land-sea thermal contrast is one of the most important physical processes correlating with the zonal movement of the IIE, in which the release of latent heating over eastern East Asia makes the greatest contribution. When a lower apparent moisture sink occurs over the South China Sea but a higher one over southern China, an anomalously positive land-sea thermal contrast is formed. An anomalous convergent zone in relation to the positive land-sea thermal contrast, located in the eastern part of the IIE, will favor the IIE to move more eastward than normal, and vice versa. An anomalous divergent zone located in the eastern part of the IIE will benefit the IIE to shift more westward than normal. Experiments using a linear baroclinic model confirm the physical processes revealed by the observational analysis.

  14. Atmospheric correction of SeaWiFS ocean color imagery in the presence of absorbing aerosols off the Indian coast using a neuro-variational method

    NASA Astrophysics Data System (ADS)

    Brajard, J.; Moulin, C.; Thiria, S.

    2008-10-01

    This paper presents a comparison of the atmospheric correction accuracy between the standard sea-viewing wide field-of-view sensor (SeaWiFS) algorithm and the NeuroVaria algorithm for the ocean off the Indian coast in March 1999. NeuroVaria is a general method developed to retrieve aerosol optical properties and water-leaving reflectances for all types of aerosols, including absorbing ones. It has been applied to SeaWiFS images of March 1999, during an episode of transport of absorbing aerosols coming from pollutant sources in India. Water-leaving reflectances and aerosol optical thickness estimated by the two methods were extracted along a transect across the aerosol plume for three days. The comparison showed that NeuroVaria allows the retrieval of oceanic properties in the presence of absorbing aerosols with a better spatial and temporal stability than the standard SeaWiFS algorithm. NeuroVaria was then applied to the available SeaWiFS images over a two-week period. NeuroVaria algorithm retrieves ocean products for a larger number of pixels than the standard one and eliminates most of the discontinuities and artifacts associated with the standard algorithm in presence of absorbing aerosols.

  15. High-resolution estimates of Nubia-Somalia plate motion since 20 Ma from reconstructions of the Southwest Indian Ridge, Red Sea, and Gulf of Aden

    NASA Astrophysics Data System (ADS)

    DeMets, C.; Merkuryev, S. A.

    2015-12-01

    We estimate Nubia-Somalia rotations at ~1-Myr intervals for the past 20 Myr from newly available, high-resolution reconstructions of the Southwest Indian Ridge and reconstructions of the Red Sea and Gulf of Aden. The former rotations are based on many more data, extend farther back in time, and have more temporal resolution than has previously been the case. Nubia-Somalia plate motion has remained remarkably steady since 5.2 Ma. For example, at the northern end of the East Africa rift, our Nubia-Somalia plate motion estimates at six different times between 0.78 Ma and 5.2 Ma agree to within 3% with the rift-normal component of motion that is extrapolated from the recently estimated Saria et al. (2014) GPS angular velocity. Over the past 10.6 Myr, the Nubia-Somalia rotations predict 42±4 km of rift-normal extension across the northern segment of the Main Ethiopian Rift. This agrees with approximate minimum and maximum estimates of 40 km and 53 km for post-10.6-Myr extension from seismological surveys of this narrow part of the plate boundary and is also close to 55-km and 48±3 km estimates from published and our own reconstructions of the Nubia-Arabia and Somalia-Arabia seafloorspreading histories for the Red Sea and Gulf of Aden. Our new rotations exclude at high confidence level two previously published estimates of Nubia-Somalia motion based on inversions of Chron 5n.2 along the Southwest Indian Ridge, which predict rift-normal extensions of 13±14 km and 129±16 km across the Main Ethiopian Rift since 11 Ma. Constraints on Nubia-Somalia motion before ~15 Ma are weaker due to sparse coverage of pre-15-Myr magnetic reversals along the Nubia-Antarctic plate boundary, but appear to require motion before 15 Ma. Nubia-Somalia rotations that we estimate from a probabilistic analysis of geometric and age constraints from the Red Sea and Gulf of Aden are consistent with those determined from Southwest Indian Ridge data, particularly for the past 11 Myr. Nubia

  16. Platyrhina psomadakisi sp. nov., a new species of fanray (Batoidea: Platyrhinidae) from the Andaman Sea, the first record of this family in the Indian Ocean.

    PubMed

    White, William T; Last, Peter R

    2016-01-01

    A new species of fanray (Platyrhina) is described based on four specimens collected in 2015 from the Andaman Sea, off Myanmar. These represent the first records of the family Platyrhinidae from the Indian Ocean with the three other members of the genus being restricted to the North-West Pacific. The new species differs from its congeners in having a series of faint dark bands on the body and tail, more pectoral-fin radials, and much more widely separated dorsal fins. PMID:27395241

  17. 76 FR 11494 - List of Recipients of Indian Health Scholarships Under the Indian Health Scholarship Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-02

    ... Health Sciences Center, Cherokee Nation, Oklahoma Battese, Anthony Steven, Northeastern State University... Oklahoma Beck, Dustin Ryan, Oklahoma State University, Cherokee Nation, Oklahoma Begay, Lisa, Arizona... Band of Chippewa Indians of North Dakota Bighorse, Amanda Nicole, Oklahoma State University,...

  18. Geology of northeastern Montana

    USGS Publications Warehouse

    Collier, Arthur J.

    1919-01-01

    A large region in northeastern Montana has never been thoroughly explored by geologists, owing to the fact that it is a part of the Great Plains and the belief that it is too monotonous and uninteresting to tempt anyone to turn aside from the pronounced geologic features a little farther west, for which Montana is noted. This region includes parts of Sheridan, Valley, Phillips, and Blaine counties. Its investigation was begun by Smith in 1908, when he made a geologic survey of the Fort Peck Indian Reservation. Beekly explored a strip of land along the Montana-North Dakota line from Missouri River to the international boundary, and Bauer examined the townships in which Plentywood and Scobey are situated. Their results are here included with those of the writer, who during the field seasons of 1915 and 1916 was engaged in an investigation of the lignite resources of the remainder of this region, which extends from a line within 12 miles of the Montana-North Dakota boundary westward about 200 miles.

  19. The middle Holocene climatic records from Arabia: Reassessing lacustrine environments, shift of ITCZ in Arabian Sea, and impacts of the southwest Indian and African monsoons

    NASA Astrophysics Data System (ADS)

    Enzel, Yehouda; Kushnir, Yochanan; Quade, Jay

    2015-06-01

    A dramatic increase in regional summer rainfall amount has been proposed for the Arabian Peninsula during the middle Holocene (ca. 9-5 ka BP) based on lacustrine sediments, inferred lake levels, speleothems, and pollen. This rainfall increase is considered primarily the result of an intensified Indian summer monsoon as part of the insolation-driven, northward shift of the boreal summer position of the Inter-Tropical Convergence Zone (ITCZ) to over the deserts of North Africa, Arabia, and northwest India. We examine the basis for the proposed drastic climate change in Arabia and the shifts in the summer monsoon rains, by reviewing paleohydrologic lacustrine records from Arabia. We evaluate and reinterpret individual lake-basin status regarding their lacustrine-like deposits, physiography, shorelines, fauna and flora, and conclude that these basins were not occupied by lakes, but by shallow marsh environments. Rainfall increase required to support such restricted wetlands is much smaller than needed to form and maintain highly evaporating lakes and we suggest that rainfall changes occurred primarily at the elevated edges of southwestern, southern, and southeastern Arabian Peninsula. These relatively small changes in rainfall amounts and local are also supported by pollen and speleothems from the region. The changes do not require a northward shift of the Northern Hemisphere summer ITCZ and intensification of the Indian monsoon rainfall. We propose that (a) latitudinal and slight inland expansion of the North African summer monsoon rains across the Red Sea, and (b) uplifted moist air of this monsoon to southwestern Arabia highlands, rather than rains associated with intensification of Indian summer monsoon, as proposed before, increased rains in that region; these African monsoon rains produced the modest paleo-wetlands in downstream hyperarid basins. Furthermore, we postulate that as in present-day, the ITCZ in the Indian Ocean remained at or near the equator all

  20. Basin-wide modification of dynamical and biogeochemical processes by the positive phase of the Indian Ocean dipole during the SeaWiFS era

    NASA Astrophysics Data System (ADS)

    Wiggert, Jerry D.; Vialard, Jérôme; Behrenfeld, Michael J.

    Characterizing how the Indian Ocean dipole (IOD) modifies typical basin-wide dynamical variability has been vigorously pursued over the past decade. Along with this dynamic response, a clear biological impact has been revealed in the ocean color data acquired by remote sensing platforms such as Sea-viewing Wide Field-of-View Sensor (SeaWiFS). The signature feature illustrating IOD alteration of typical spatiotemporal chlorophyll variability is the phytoplankton bloom that first appears in September along the eastern boundary of the IO in tropical waters that are normally highly oligotrophic. Positive chlorophyll anomalies (CLa) are also apparent in the southeastern Bay of Bengal, while negative anomalies are observed over much of the Arabian Sea. Moreover, in situ measurements obtained by the R/V Suroit as part of the Cirene cruise during the 2006/2007 IOD reveal anomalous subsurface biochemical distributions in the southern tropical IO that are not reflected in SeaWiFS data. Despite the clear basin-wide influence of IOD events on biological variability, the accompanying influence on biogeochemical cycling that must occur has received little attention. Here, the dynamical signatures apparent in remote sensing fields for the two positive-phase IODs of the SeaWiFS era are used to illuminate how these events are similar or distinct. A corresponding comparison of IOD-engendered surface CLa is performed, with the dynamical fields providing the framework for interpreting the mechanisms underlying the biological response. Then, results from a newly developed net primary production algorithm are presented that provide the first characterization of how biogeochemical fluxes throughout the IO are altered by IOD occurrence

  1. Millennial/centennial-scale thermocline ventilation changes in the Indian Ocean as reflected by aragonite preservation and geochemical variations in Arabian Sea sediments

    NASA Astrophysics Data System (ADS)

    Böning, Philipp; Bard, Edouard

    2009-11-01

    The formation and temporal variability of the oxygen minimum zone (OMZ) of the Arabian Sea is a subject of intense research. We contribute to the discussion by studying modern seawater profiles of the Indian Ocean (salinity, O 2, pH, aragonite saturation, nitrate deficit, nutrients), which show that Subantarctic Mode and Antarctic Intermediate Waters (SAMW-AAIW) have a strong influence on the OMZ characteristics of the Arabian Sea. To obtain a better grasp of the range of possible OMZ variations, we studied a 50-kyr record in the NE Arabian Sea (core MD042876) from a site at 828 m water depth within the thermocline. In this core, aragonite is preserved during North Atlantic Heinrich events (HEs) and Dansgaard-Oeschger (DO) stadials, while it is absent during DO interstadials and most of the Holocene. Considering the excellent correlation between aragonite content and Sr/Ca ratio, as well as the presence of fine-grained aragonitic needles and the isotopic composition (δ 13C) of carbonates in the fine fraction, we infer that essentially all aragonite originates as fine Sr-rich debris from shallow water. A comparison with other records from the NE Arabian Sea (Sr/Ca, δ 15N) indicates that aragonite variability in the cores is rather controlled by OMZ intensity variations as forcing mechanism while changes in aragonite supply seem to play a minor role. The strong correlation of aragonite content with changes in millennial-scale ventilation of the Indian Ocean, as well as a comparison with modern oceanographic conditions, supports the theory that OMZ intensity variations are controlled by changes in the formation of SAMW-AAIW, and are not only due to monsoonal changes. Thus, during HEs and DO stadials, the thermocline Arabian Sea experienced a strengthened influx of O 2-rich SAMW-AAIW. On the other hand, OMZ conditions during DO interstadials and the Holocene seem best explained by analogy with the present-day situation: low supply of O 2 combined with elevated O 2

  2. Can Indian Ocean SST anomalies influence South American rainfall?

    NASA Astrophysics Data System (ADS)

    Taschetto, Andréa S.; Ambrizzi, Tércio

    2012-04-01

    In this study we examine the impact of Indian Ocean sea surface temperature (SST) variability on South American circulation using observations and a suite of numerical experiments forced by a combination of Indian and Pacific SST anomalies. Previous studies have shown that the Indian Ocean Dipole (IOD) mode can affect climate over remote regions across the globe, including over South America. Here we show that such a link exists not only with the IOD, but also with the Indian Ocean basin-wide warming (IOBW). The IOBW, a response to El Niño events, tends to reinforce the South American anomalous circulation in March-to-May associated with the warm events in the Pacific. This leads to increased rainfall in the La Plata basin and decreased rainfall over the northern regions of the continent. In addition, the IOBW is suggested to be an important factor for modulating the persistence of dry conditions over northeastern South America during austral autumn. The link between the IOBW and South American climate occurs via alterations of the Walker circulation pattern and through a mid-latitude wave-train teleconnection.

  3. Radiocarbon Ages from Two Submerged Strandline Features in the Western Gulf of Maine and a Sea-Level Curve for the Northeastern Massachusetts Coastal Region

    USGS Publications Warehouse

    Oldale, R.N.; Colman, Steven M.; Jones, Glenn A.

    1993-01-01

    New radiocarbon dates provide ages for two submerged strandline features on the Massachusetts inner shelf. These ages provide limited control on a relative sea-level (RSL) curve for the late Wisconsinan and Holocene. The curve indicates a late Wisconsinan high stand of RSL of +33 m about 14,000 yr ago and a very short-lived relative low stand of about -43 m at about 12,000 yr ago followed by a rise to present sea level. Rapid changes of RSL around 12,000 yr ago may be related to changes in global glacial meltwater discharge and eustatic sea-level change shown by dated corals off Barbados. Variations in the magnitude and timing of RSL change from south to north along the coast of the western Gulf of Maine are due to greater crustal depression and later deglaciation to the north.

  4. High-resolution estimates of Nubia-Somalia plate motion since 20 Ma from reconstructions of the Southwest Indian Ridge, Red Sea, and Gulf of Aden

    NASA Astrophysics Data System (ADS)

    DeMets, C.; Merkouriev, S.

    2016-07-01

    Large gaps and inconsistencies remain in published estimates of Nubia-Somalia plate motion based on reconstructions of seafloor spreading data around Africa. Herein, we use newly available reconstructions of the Southwest Indian Ridge at ˜1-Myr intervals since 20 Ma to estimate Nubia-Somalia plate motion farther back in time than previously achieved and with an unprecedented degree of temporal resolution. At the northern end of the East African rift, our new estimates of Nubia-Somalia motion for six times from 0.78 Ma to 5.2 Ma differ by only 2% from the rift-normal component of motion that is extrapolated from a recently estimated GPS angular velocity. The rate of rift-normal extension thus appears to have remained steady since at least 5.2 Ma. Our new rotations indicate that the two plates have moved relative to each other since at least 16 Ma and possibly longer. Motion has either been steady since at least 16 Ma or accelerated modestly between 6 and 5.2 Ma. Our Nubia-Somalia rotations predict 42.5±3.8 km of rift-normal extension since 10.6 Ma across the well-studied, northern segment of the Main Ethiopian Rift, consistent with 40-50 km estimates for extension since 10.6 Myr based on seismological surveys of this narrow part of the plate boundary. Nubia-Somalia rotations are also derived by combining newly estimated Somalia-Arabia rotations that reconstruct the post-20-Ma opening of the Gulf of Aden with Nubia-Arabia rotations estimated via a probabilistic analysis of plausible opening scenarios for the Red Sea. These rotations predict Nubia-Somalia motion since 5.2 Myr that is consistent with that determined from Southwest Indian Ridge data and also predict 40±3 km of rift-normal extension since 10.6 Ma across the Main Ethiopian Rift, consistent with our 42.5±3.8 km Southwest Indian Ridge estimate. Our new rotations exclude at high confidence level previous estimates of 12±13 km and 123±14 km for rift-normal extensions across the Main Ethiopian Rift since

  5. Nutrient enrichment and precipitation changes do not enhance resiliency of salt marshes to sea level rise in the Northeastern U.S.

    EPA Science Inventory

    In the U.S. Northeast, salt marshes are exceptionally vulnerable to the effects of accelerated sea level rise as compensatory mechanisms relying on positive feedbacks between inundation and sediment deposition are insufficient to counter inundation increases in low turbidity tida...

  6. High Connectivity of Animal Populations in Deep-Sea Hydrothermal Vent Fields in the Central Indian Ridge Relevant to Its Geological Setting

    PubMed Central

    Beedessee, Girish; Watanabe, Hiromi; Ogura, Tomomi; Nemoto, Suguru; Yahagi, Takuya; Nakagawa, Satoshi; Nakamura, Kentaro; Takai, Ken; Koonjul, Meera; Marie, Daniel E. P.

    2013-01-01

    Dispersal ability plays a key role in the maintenance of species in spatially and temporally discrete niches of deep-sea hydrothermal vent environments. On the basis of population genetic analyses in the eastern Pacific vent fields, dispersal of animals in the mid-oceanic ridge systems generally appears to be constrained by geographical barriers such as trenches, transform faults, and microplates. Four hydrothermal vent fields (the Kairei and Edmond fields near the Rodriguez Triple Junction, and the Dodo and Solitaire fields in the Central Indian Ridge) have been discovered in the mid-oceanic ridge system of the Indian Ocean. In the present study, we monitored the dispersal of four representative animals, Austinograea rodriguezensis, Rimicaris kairei, Alviniconcha and the scaly-foot gastropods, among these vent fields by using indirect methods, i.e., phylogenetic and population genetic analyses. For all four investigated species, we estimated potentially high connectivity, i.e., no genetic difference among the populations present in vent fields located several thousands of kilometers apart; however, the direction of migration appeared to differ among the species, probably because of different dispersal strategies. Comparison of the intermediate-spreading Central Indian Ridge with the fast-spreading East Pacific Rise and slow-spreading Mid-Atlantic Ridge revealed the presence of relatively high connectivity in the intermediate- and slow-spreading ridge systems. We propose that geological background, such as spreading rate which determines distance among vent fields, is related to the larval dispersal and population establishment of vent-endemic animal species, and may play an important role in controlling connectivity among populations within a biogeographical province. PMID:24358117

  7. High connectivity of animal populations in deep-sea hydrothermal vent fields in the Central Indian Ridge relevant to its geological setting.

    PubMed

    Beedessee, Girish; Watanabe, Hiromi; Ogura, Tomomi; Nemoto, Suguru; Yahagi, Takuya; Nakagawa, Satoshi; Nakamura, Kentaro; Takai, Ken; Koonjul, Meera; Marie, Daniel E P

    2013-01-01

    Dispersal ability plays a key role in the maintenance of species in spatially and temporally discrete niches of deep-sea hydrothermal vent environments. On the basis of population genetic analyses in the eastern Pacific vent fields, dispersal of animals in the mid-oceanic ridge systems generally appears to be constrained by geographical barriers such as trenches, transform faults, and microplates. Four hydrothermal vent fields (the Kairei and Edmond fields near the Rodriguez Triple Junction, and the Dodo and Solitaire fields in the Central Indian Ridge) have been discovered in the mid-oceanic ridge system of the Indian Ocean. In the present study, we monitored the dispersal of four representative animals, Austinograea rodriguezensis, Rimicaris kairei, Alviniconcha and the scaly-foot gastropods, among these vent fields by using indirect methods, i.e., phylogenetic and population genetic analyses. For all four investigated species, we estimated potentially high connectivity, i.e., no genetic difference among the populations present in vent fields located several thousands of kilometers apart; however, the direction of migration appeared to differ among the species, probably because of different dispersal strategies. Comparison of the intermediate-spreading Central Indian Ridge with the fast-spreading East Pacific Rise and slow-spreading Mid-Atlantic Ridge revealed the presence of relatively high connectivity in the intermediate- and slow-spreading ridge systems. We propose that geological background, such as spreading rate which determines distance among vent fields, is related to the larval dispersal and population establishment of vent-endemic animal species, and may play an important role in controlling connectivity among populations within a biogeographical province. PMID:24358117

  8. Checklist of Recent thecideoid brachiopods from the Indian Ocean and Red Sea, with a description of a new species of Thecidellina from Europa Island and a re-description of T. blochmanni Dall from Christmas Island.

    PubMed

    Logan, Alan; Hoffmann, Jana; Lüter, Carsten

    2015-01-01

    Compilation of a checklist of Recent thecideoid brachiopods from the Indian Ocean and Red Sea indicates that members of this superfamily are represented by a small number of species. The subfamily Lacazellinae is represented by Ospreyella maldiviana from the Maldive Islands but the presence of Lacazella cannot yet be confirmed in the Indian Ocean as the holotype of Lacazella mauritiana from Mauritius is lost. The subfamily Thecidellininae is represented by Thecidellina blochmanni from Christmas Island in the eastern Indian Ocean and the Red Sea while a new species T. europa is here described from Europa Island in the Mozambique Channel. The subfamily Minutellinae is represented by Minutella minuta from Samper Bank and Walters Bank in the south-western Indian Ocean and in the Red Sea. Since the holotype of Thecidellina blochmanni from Flying Fish Cove, Christmas Island is also lost, this species is re-described and illustrated mainly from topotypes in the Museum für Naturkunde, Berlin, from which a suggested neotype has been selected. PMID:26623894

  9. Monsoon-ocean coupled modes in the South China Sea and their linkage with the eastern Indian Ocean-western Pacific warm pool

    NASA Astrophysics Data System (ADS)

    Huang, Fei; Yang, Yuxing; Huang, Jian

    2008-02-01

    Monsoon-ocean coupled modes in the South China Sea (SCS) were investigated by a combined singular value decomposition (CSVD) analysis based on sea surface temperature (SST) and sea surface wind stress (SWS) fields from SODA (Simple Ocean Data Assimilation) data spanning the period of 1950 1999. The coupled fields achieved the maximum correlation when the SST lagged SWS by one month, indicating that the SCS coupled system mainly reflected the response of the SST to monsoon forcing. Three significant coupled modes were found in the SCS, accounting for more than 80% of the cumulative squared covariance fraction. The first three SST spatial patterns from CSVD were: (I) the monopole pattern along the isobaths in the SCS central basin; (II) the north-south dipole pattern; and (III) the west-east seesaw pattern. The expansion coefficient of the SST leading mode showed interdecadal and interannual variability and correlation with the Indo-Pacific warm pool (IPWP), suggesting that the SCS belongs to part of the IPWP at interannual and interdecadal time scales. The second mode had a lower correlation coefficient with the warm pool index because its main period was at intra-annual time scales instead of the interannual and interdecadal scales with the warm pools. The third mode had similar periods to those of the leading mode, but lagged the eastern Indian Ocean warm pool (EIWP) and western Pacific warm pool (WPWP) by five months and one year respectively, implying that the SCS response to the warm pool variation occurred from the western Pacific to the eastern Indian Ocean, which might have been related to the variation of Indonesian throughflow. All three modes in the SCS had more significant correlations with the EIWP, which means the SCS SST varied much more coherently with the EIWP than the WPWP, suggesting that the SCS belongs mostly to part of the EIWP. The expansion coefficients of the SCS SST modes all had negative correlations with the Niño3 index, which they lag

  10. Joint influence of the Indo-Pacific Warm Pool and Northern Arabian Sea Temperatures on the Indian Summer Monsoon in a Global Climate Model Simulation

    NASA Astrophysics Data System (ADS)

    Befort, Daniel J.; Leckebusch, Gregor C.; Cubasch, Ulrich

    2016-04-01

    Proxy-based studies confirmed that the Indian Summer Monsoon (ISM) shows large variations during the Holocene. These changes might be explained by changes in orbital conditions and solar insolation but are also thought to be associated to changes in oceanic conditions, e.g. over the Indo-Pacific-Warm-Pool region. However, due to the nature of these (proxy-based) analyses no conclusion about atmospheric circulation changes during dry and wet epochs are possible. Here, a fully-coupled global climate simulation (AOGCM) covering the past 6000 years is analysed regarding ISM variability. Several dry and wet epochs are found, the most striking around 2ka BP (dry) and 1.7ka BP (wet). As only orbital parameters change during integration, we expect these "shorter-term" changes to be associated with changes in oceanic conditions. During 1.7ka BP the sea surface temperatures (SST) over the Northern Arabian Sea (NARAB) are significantly warmer compared to 2ka BP, whereas cooler conditions are found over the western Pacific Ocean. Additionally, significant differences are found over large parts of the North Atlantic. To explain in how far these different ocean basins are responsible for anomalous conditions during 1.7ka BP, several sensitivity experiments with changed SST/SIC conditions are carried out. It is found that neither the SST's in the Pacific nor in the Indian Ocean are able to reproduce the anomalous rainfall and atmospheric circulation patterns during 1.7ka on its own. Instead, anomalous dry conditions during 2ka BP and wet conditions during 1.7ka BP are associated with a shift of the Indo-Pacific-Warm-Pool (IPWP) and simultaneous anomalous sea-surface temperatures over the NARAB region. Eventually, it is tested in how far this hypothesis holds true for other dry and wet events in the AOGCM data during the whole 6000 years. In general, a shift of the IPWP without anomalous SST conditions over the NARAB region (and vice versa) is not sufficient to cause long

  11. The Study of Geotechnical Properties of Sediment in C-C Zone in the Northeastern Pacific for Deep-sea Mining

    NASA Astrophysics Data System (ADS)

    Chi, S.; Kim, K.; Lee, H.; Ju, S.; Yoo, C.

    2007-12-01

    Recently the market price of valuable metals are rapidly increased due to the high demand and limited resources. Therefore, manganese (Mn)-nodules (Polymetallic nodules) in the Clarion-Clipperton fracture zone have stimulated economic interest. Nickel, copper, cobalt and manganese are the economically most interesting metals of Mn-nodules. In order to mine Mn-nodules from sea floor, understanding the geotechnical properties of surface sediment are very important for two major reasons. First, geotechnical data are required to design and build the stable and environmentally acceptable mining vehicles. Second, deep-sea mining activity could significantly effect on the surface layer of deep sea floor. For example, surface sediments will be redistributed through the resuspension and redeposition. Reliable sedimentological and soil mechanical baseline data of the undisturbed benthic environment are essential to assess and evaluate these environmental impacts by mining activity using physical and numerical modeling. The 225 times deployments of the multiple corer guaranteed undisturbed sediment samples in which geotechnical parameters were measured including sediment grain size, density, water content, shear strength. The sea floor sediments in this study area are generally characterized into three different types as follow. The seabed of the middle part (8-12° N) of this study area is mainly covered with biogenic siliceous sediment compared with pelagic red clays in the northern part (16-17° N). However, the southern part (5-6° N) is dominant with calcareous sediments because its water depth is shallower than the carbonate compensation depth (CCD). This result suggests that middle area, covered with siliceous sediment, is more feasible for commercial mining than northern area, covered with pelagic red clay, with the consideration of the nodule miner maneuverability and the environmental impact. Especially, middle part with the highest nodule abundance and valuable

  12. Iridium in sediments containing large abundances of Australasian microtektites from DSDP hole 758B in the Eastern Indian Ocean and from DSDP hole 769A in the Sulu Sea

    NASA Technical Reports Server (NTRS)

    Schmidt, Gerhard; Zhou, Lei; Wasson, John T.

    1993-01-01

    Excess Ir found in sediments at the Cretaceous/Tertiary (K/T) boundary and in other (e.g., Pliocene) sediments from deep sea drilling cores is widely interpreted as evidence of major impact events. The Australasian tektites originated in an impact event approximately 0.77 Ma ago; microtektites have been found in deep-sea sediment cores from throughout the Indian Ocean, the Philippine Sea, and western Pacific Ocean, but Ir has not been previously reported in these horizons. The deep-sea record of tektites is of particular interest, because in contrast to most continental occurrences, the stratigraphy preserves the original depositional position. Recently several cores having exceptionally high contents of Australasian microtektites have been investigated, Glass and Wu found shocked quartz associated with the microtektites. We used neutron activation to determine concentrations of Ir and other elements in two cores bearing microtektites, one from Deep Sea Drilling Project (DSDP) hole 758B in the Eastern Indian Ocean and one from DSDP hole 769A in the Sulu Sea (near Mindanao, Philippines). The sedimentation age for the microtektite layers in core 758B lies between 0.73 - 0.78 Ma and agrees well with the mean laser-fusion Ar-40/Ar-39 age of Australasian tektites of 0.77 +/- 0.02 Ma by Izett et al. We are able to resolve a small positive Ir enhancement in 758B. Core 769A shows too much scatter to allow resolution of an Ir peak.

  13. Bacterial community shift is induced by dynamic environmental parameters in a changing coastal ecosystem (northern Adriatic, northeastern Mediterranean Sea)--a 2-year time-series study.

    PubMed

    Tinta, T; Vojvoda, J; Mozetič, P; Talaber, I; Vodopivec, M; Malfatti, F; Turk, V

    2015-10-01

    The potential link between the microbial dynamics and the environmental parameters was investigated in a semi-enclosed and highly dynamic coastal system (Gulf of Trieste, northern Adriatic Sea, NE Mediterranean Sea). Our comprehensive 2-year time-series study showed that despite the shallowness of this area, there was a significant difference between the surface and the bottom bacterial community structure. The bottom bacterial community was more diverse than the surface one and influenced by sediment re-suspension. The surface seawater temperature had a profound effect on bacterial productivity, while the bacterial community structure was more affected by freshwater-borne nutrients and phytoplankton blooms. Phytoplankton blooms caused an increase of Gammaproteobacteria (Alteromonadaceae, SAR86 and Vibrionaceae) and shift in dominance from SAR11 to Rhodobacteraceae taxon at the surface. Our results propose the importance of the water mass movements as drivers of freshwater-borne nutrients and of allochthonous microbial taxa. This study emphasizes the prediction power based on association networks analyses that are fed with long-term measurements of microbial and environmental parameters. These interaction maps offer valuable insights into the response of marine ecosystem to climate- and anthropogenic-driven stressors. PMID:24903068

  14. Demography of a deep-sea lantern shark (Etmopterus spinax) caught in trawl fisheries of the northeastern Atlantic: Application of Leslie matrices with incorporated uncertainties

    NASA Astrophysics Data System (ADS)

    Coelho, Rui; Alpizar-Jara, Russell; Erzini, Karim

    2015-05-01

    The deep-sea lantern shark Etmopterus spinax occurs in the northeast Atlantic on or near the bottoms of the outer continental shelves and slopes, and is regularly captured as bycatch in deep-water commercial fisheries. Given the lack of knowledge on the impacts of fisheries on this species, a demographic analysis using age-based Leslie matrices was carried out. Given the uncertainties in the mortality estimates and in the available life history parameters, several different scenarios, some incorporating stochasticity in the life history parameters (using Monte Carlo simulation), were analyzed. If only natural mortality were considered, even after introducing uncertainties in all parameters, the estimated population growth rate (λ) suggested an increasing population. However, if fishing mortality from trawl fisheries is considered, the estimates of λ either indicated increasing or declining populations. In these latter cases, the uncertainties in the species reproductive cycle seemed to be particularly relevant, as a 2-year reproductive cycle indicated a stable population, while a longer (3-year cycle) indicated a declining population. The estimated matrix elasticities were in general higher for the survivorship parameters of the younger age classes and tended to decrease for the older ages. This highlights the susceptibility of this deep-sea squaloid to increasing fishing mortality, emphasizing that even though this is a small-sized species, it shows population dynamics patterns more typical of the larger-sized and in general more vulnerable species.

  15. Mantle heterogeneity in northeastern Africa: evidence from Nd isotopic compositions and hygromagmaphile element geochemistry of basaltic rocks from the Gulf of Tadjoura and southern Red Sea regions

    NASA Astrophysics Data System (ADS)

    Barrat, J.-A.; Jahn, B. M.; Joron, J.-L.; Auvray, B.; Hamdi, H.

    1990-12-01

    Basaltic rocks from the Gulf of Tadjoura and southern Red Sea regions have been analysed for their Nd isotopic compositions and major and trace element concentrations. The wide variation in isotopic and geochemical compositions of the basaltic rocks is best explained by the mixing phenomenon involving a variety of mantle source components. To test the mixing hypothesis, a combined use of Nd isotopes and hygromagmaphile elemental ratios is proven very powerful. Three reservoirs have been identified as minimum components in their petrogenesis: (1) DMM (depleted MORB mantle), a mantle source depleted in light rare earth elements (LREE), which is the principal component of the N-MORB type basalts of this region; (2) REC (Ramad enriched component), equivalent to the hot-spot type of source detected in the south of Red Sea; (3) TEC (Tadjoura enriched component), a rather unique component located in the region of Tadjoura Gulf; it is characterised by a relative depletion in Rb, K, Th and U in a primitive mantle- or chondrite-normalised incompatible element pattern; this component could have been produced by mantle metasomatism of an originally depleted mantle. Mixing in various proportions of the above components is considered to be the principal mechanism for the formation of basalts with such diverse isotopic and trace element compositions.

  16. Milankovitch forcing and role of Indonesian Gateway on middle Miocene climate and carbon cycle: New perspective from the South China Sea, equatorial West Pacific and East Indian Ocean

    NASA Astrophysics Data System (ADS)

    Holbourn, A.; Kuhnt, W.; Schulz, M.

    2003-04-01

    The enigmatic long-term positive carbon isotope excursion ("Monterey excursion") in the middle Miocene exhibits an apparent 400 ky cyclicity (long eccentricity cycle of the Milankovitch frequency band). Similar isotope excursion are known from the mid-Cretaceous and may be a characteristic feature of a greenhouse world with extreme warm climate, high sealevel, and a dominantly zonal circulation pattern in the world ocean. This period of extreme warmth (the mid-Miocene climate optimum) ended between 14.2 and 13.8 Ma, when a significant increase in deep-water oxygen isotopic values occurred that was related to the growth of the East Antarctic ice sheet. Plate tectonic movements between Australia and SE Asia, ultimately leading to the closure of the deep water gateway connecting the Indian and Pacific Oceans, started prior to this paleoceanographic change. We used benthic deep water oxygen and carbon isotope curves in combination with new age models at critical locations along the northern margin of the Indonesian Gateway (South China Sea, ODP Site 1146), at the western end of the gateway (NW Australian margin, ODP Site 761) and at the eastern end of the gateway (Ontong Java Plateau, ODP Site 806) to investigate the frequency and amplitude of deep water isotope fluctuations during the middle Miocene. High resolution sediment color reflectance data, benthic carbon isotopes and foraminiferal assemblages are used as proxies of deep-water ventilation and carbon flux. Our results indicate Milankovitch forcing on virtually all proxies and a change from eccentricity to precession driven cyclicity at approximately 15 Ma. Our data reveal increased carbon flux and a restricted deep water exchange between the Pacific Ocean and Indian Ocean through the Indonesian Gateway during the middle Miocene climate optimum. After 13.6 Ma, the decrease in d13C was strongest at Site 806, indicating a marked change in the deep-water circulation of the equatorial West Pacific and a switch to a

  17. Understanding the life of a sandy beach polychaete of functional importance - Scolelepis squamata (Polychaeta: Spionidae) on Belgian sandy beaches (northeastern Atlantic, North Sea)

    NASA Astrophysics Data System (ADS)

    Speybroeck, Jeroen; Alsteens, Lotte; Vincx, Magda; Degraer, Steven

    2007-08-01

    The cosmopolitan sandy beach polychaete Scolelepis squamata constitutes an important food resource for juvenile flatfish and wading birds in the northeastern Atlantic, thus playing an important role in sandy beach ecosystem functioning. However, its population dynamics and life history in this part of the world have gone widely uninvestigated. Eight beach transects on Belgian sandy beaches were sampled monthly from October 2003 until October 2004, in order to investigate seasonal trends in the species' abundance, biomass, secondary production, and patterns in reproduction and zonation. Average density, modal density and modal biomass (ash-free dry weight) (mean average density = 169 ± 9 SE ind/m 2; mean modal density = 505 ± 38 SE ind/m 2; mean modal biomass = 0.25 ± 0.02 SE g/m 2) did not exhibit major seasonal changes, whereas average biomass (0.081 ± 0.005 SE g/m 2) and individuals and biomass per strip transect (IST = 16286 ± 1330 SE ind/m; BMST = 7.8 + 0.7 SE g/m) did, peaking in May 2004. Production was calculated at 1.9 g/(m 2*year) (size-frequency method, SFM) and 0.88 g/(m 2*year) (mass specific growth rate method, MSGR) and mean annual biomass was 0.797 g/m 2; resulting in a P/B ratio of 2.40/year (SFM) and 1.11/year (MSGR), which is intermediate to moderately low compared to other polychaete species. Gravid individuals were found from February until August and a single recruitment period was observed from July until September. An average sex ratio of 1.41 ± 0.08 SE was calculated, with a female predominance. Highest densities (>200 ind/m 2) were mostly found above 3 m above MLLWS and at a median grain size from 190 to 320 μm. Average modal or peak density along each transect was situated from 3.95 m up to 4.40 m above MLLWS, in contrast to some other studies where the species was restricted to mid-tidal levels. Significant differences in elevation of peak density were found between non-gravid (411 ± 4 SE cm) and gravid (402 ± 5 SE cm) animals

  18. The cumbiasins, structurally novel diterpenes possessing intricate carbocyclic skeletons from the West Indian sea whip Pseudopterogorgia elisabethae (Bayer).

    PubMed

    Rodríguez, A D; Ramírez, C; Shi, Y P

    2000-10-01

    From the hexane extract of the West Indian gorgonian Pseudopterogorgia elisabethae, two diterpenes, cumbiasins A (1) and B (2), having a novel tetracyclic carbon skeleton named cumbiane, have been isolated. In addition, we have isolated cumbiasin C (3), a ring cleavage product of cumbiasin B that possesses an unusual carbocyclic framework named seco-cumbiane. The structures and relative configurations of metabolites 1-3 were elucidated by interpretation of overall spectral data, which included 2D NMR correlation methods, IR, UV, and accurate mass measurements (HREI-MS and HRFAB-MS). The carbocyclic skeletons of the cumbiasins are unprecedented and represent new classes of C20 rearranged diterpenes. Cumbiasins A and B display mild in vitro anti-tuberculosis activity. PMID:11052119

  19. Planktic foraminiferal assemblages from laminated sediments of the northeastern Arabian Sea: a high-resolution study over the last two millennia

    NASA Astrophysics Data System (ADS)

    Munz, Philipp; Lückge, Andreas; Siccha, Michael; Kucera, Michal; Schulz, Hartmut

    2014-05-01

    Modern planktic foraminiferal assemblages in the Arabian Sea are largely controlled by seasonal shifts of surface water properties. Boreal summer (June-September) heating of the Asian landmass and Tibetan Plateau leads to northward migration of the ITCZ and develops an intense atmospheric pressure gradient. Strong monsoonal winds from the southwest lead to coastal- and open ocean upwelling, especially in the western Arabian Sea along the coast of Somalia and Oman. Opposite directed dry and cold winds lead to deep convective mixing during boreal winter (January-March) and breakup of the thermal stratification. Deepening of the mixed-layer thus enables nutrient transport into the photic zone with enhanced primary production. Here we study planktic foraminiferal assemblages from the dominantly winter monsoon controlled Pakistan Margin off Karachi. We sampled annually laminated sediments from box core SO90-39KG and ca. 2-m-long piston core SO130-275KL from the same station. High sedimentation rates and varve-like lamination provides a particular record with very precise age control. Box core 39KG offers a record of the last 100 years with 2-year-resolution and 275KL provides a ca. 10-year-resolution during the last 2100 years. We calculated foraminiferal flux rates after photometric identification and subtraction of light-colored event layers, consisting solely of terrigeneous matter to enable comparison with flux rates from sediment trap stations. We identified a total of 28 planktic foraminiferal (PF) species/morphotypes in the fraction >150μm. During the relatively short period of the past two millennia, several species showed comparatively large fluctuations on decadal time scales, not seen in bioturbated records. Globigerina bulloides, a species generally associated with high primary production rates, fluctuates between ca. 10% and 45%. Highest relative share was observed during periods 1593-1413, 1023-923, 483-393, 63- -7 years AD. Average PF accumulation rates

  20. Depositional architecture and evolution of the Late Miocene slope channel-fan-system in the northeastern shelf-margin of South China Sea

    NASA Astrophysics Data System (ADS)

    Jiang, Jing; Lin, Changsong; Zhang, Zhongtao; Tian, Hongxun; Tao, Ze; Liu, Hanyao

    2016-04-01

    The Upper Miocene in the Pearl River Mouth Basin of northwestern shelf-margin of South China Sea Basin contains a series of slope channel - fan systems. Their depositional architecture and evolution are documented in this investigation based on an integrated analysis of cores, logs, and seismic data. Four depositional-palaeogeomorphological elements have been identified in the slope channel-fan systems as follows: broad, shallow and unconfined or partly confined outer-shelf to shelf-break channels; deeply incised and confined unidirectionally migrating slope channels; broad or U-shaped, unconfined erosional-depositional channels; frontal splays-lobes and nonchannelized sheets. The slope channels are mostly oriented NW-SE, which migrated unidirectionally northeastwards and intensively eroded almost the whole shelf-slope zone. The channel infillings are mainly mudstones, interbedded with siltstones. They might be formed by gravity flow erosion as bypassing channels. They were filled with limited gravity flow sediments at the base and mostly filled with lateral accretionary packages of bottom current deposits. At the end of the channels, a series of small-scale slope fans developed and coalesced into fan aprons along the base of the slope. The unconfined erosional-depositional channels at the upper parts of the fan-apron-systems display compound infill patterns, and commonly have concave erosional bases and convex tops. The frontal splays-lobes representing middle to distal deposits of fan-apron-systems have flat-mounded or gull-wing geometries, and the internal architectures include bidirectional downlap, progradation, and chaotic infillings. The distal nonchannelized turbidite sheets are characterized by thin-bedded, parallel to sub-parallel sheet-like geometries. Three major unconformities or obvious erosional surfaces in the channel-fan systems of the Upper Miocene are recognized, and indicate the falling of sea-level. The depositional architecture of sequences

  1. Understanding the Role of Cloud and Convective Processes in Simulating the Weaker Tropical Cyclones over Indian Seas

    NASA Astrophysics Data System (ADS)

    Kanase, Radhika D.; Mukhopadhyay, P.; Salvekar, P. S.

    2015-06-01

    This study addresses the problem of incorporating moist processes (resolving the grid scale and parameterizing the subgrid scale) at resolutions of 9 and 3 km with double- and triple-nested domains, respectively, in predicting the track and intensity of four cases of weaker tropical cyclones over the North Indian Ocean. The sensitivity experiments are carried out with three convective parameterization schemes, and the results are evaluated based on the track and intensity of cyclones. The Betts-Miller-Janjic scheme shows the most reasonable representation of track and intensity and therefore is used for all sensitivity experiments related to microphysical schemes in two and three domains. Three sets of microphysics sensitivity experiments are carried out: The first set includes experiments with parameterized moist convection (referred to as the 9-km experiment) in two domains (27 and 9 km). The second and third sets of simulation experiments are carried out at 9 km in two domains (27 and 9 km; referred to as the 9-km-noCP) and at 3 km in three domains (27 km, 9 km and 3 km; referred to as the 3-km experiment), respectively, by resolving the grid-scale convection explicitly with the four bulk microphysical schemes. The explicit moist convection treatment at 9- and 3-km resolution produces a better cyclone simulation than the parameterized convection at 9-km resolution. The latent heat released in the generation of hydrometeors such as snow and graupel in the mid-tropospheric levels appears to influence the heating within the inner core of the cyclone. The comparable and more realistic representation of mid-tropospheric heating is possibly one of the main reasons behind the improvement at 9-km-noCP and 3 km. The stronger vertical advection of moist static energy gives well-organized mesoscale convection within the cyclone environment at 9-km-noCP and 3-km resolution. This study therefore demonstrates the importance of microphysical processes in the simulation of

  2. Relative contributions of the Tibetan Plateau thermal forcing and the Indian Ocean Sea surface temperature basin mode to the interannual variability of the East Asian summer monsoon

    NASA Astrophysics Data System (ADS)

    Hu, Jun; Duan, Anmin

    2015-11-01

    Investigating the relationships among different factors impacting the East Asian summer monsoon (EASM) is urgent for improving its predictability. In the present study, two factors, the Tibetan Plateau (TP) atmospheric thermal forcing and the Indian Ocean sea surface temperature basin mode (IOBM), are selected to compare their relative contributions to the interannual variability of the EASM. Both statistical methods and numerical experiments are used to separate and compare their respective influences under realistic circumstances. The results indicate that the IOBM mainly drives an anticyclonic anomaly over the northwestern Pacific in the lower troposphere, which is consistent with the dominant mode of the EASM circulation system. Meanwhile, influences from the TP thermal forcing are primarily on the anticyclonic anomaly over the TP in the upper troposphere, together with the enhanced southwesterly over southern China and a northerly anomaly over northern China in the lower troposphere. Moreover, the TP thermal forcing seems to play a more important role than the IOBM in affecting the main rainfall belt of the EASM, which extends from the middle and lower reaches of the Yangtze River to Japan. Such a rainfall pattern anomaly is directly related to the anomalous northerly over northern China and the resultant stronger moisture convergence over the main rainfall belt region when a strong TP thermal forcing occurs. In addition, the IOBM can increase the precipitation over the southeastern TP during its positive phase and hence enhance the in situ atmospheric heat source to a certain degree.

  3. Comparison of hyperspectral measurements of the attenuation and scattering coefficients spectra with modeling results in the north-eastern Baltic Sea

    NASA Astrophysics Data System (ADS)

    Sipelgas, Liis; Raudsepp, Urmas

    2015-11-01

    The spectral variations in the attenuation and scattering coefficients measured with a hyperspectral ac-spectra (Wetlabs) instrument were analyzed from a dataset collected in the vicinity of commercial harbors on the Estonian coast of the Gulf of Finland, Baltic Sea. In total, the measured TSM concentration varied from 0.4 to 30 mg L-1 and the concentration of Chl a varied from values below the detection limit (0.05) to 23 mg m-3. The reliability of the power law describing the particle attenuation cp (λ) and scattering bp(λ) coefficients was evaluated by means of a determination coefficient (R2). The power law described the particle attenuation spectra with high accuracy (R2 > 0.67), giving the dataset an average cp (λ) slope of 1.3. In the case of particle scattering coefficients, the power law did not represent the whole dataset. Depending on a particular spectrum, the R2 varied from 0 to 1.0 and the slope varied from 1.15 to -0.56. Decomposition of bp(λ) into dominant modes using principal component analyses resulted in the first principal mode accounting for the power law dependence of bp(λ), i.e. the "mineral-type" spectrum, and the second and third mode representing the characteristic bp(λ) of dominant algal particles, i.e. the "algae-type" spectrum. From our dataset we estimated that if Chl a concentration is above 10 mg m-3 or below 5 mg m-3 then most likely the "algae-type" or the "mineral-type" spectrum is dominant, respectively. There was strong linear relationship (R2 > 0.92) between TSM concentration and cp(555) and bp(555),irrespective of the dominant shape of the particle scattering spectra. The estimated TSM-specific attenuation and scattering coefficients at 555 nm were 0.8 m2 g-1 and 0.68 m2 g-1, respectively. Corresponding values for water samples with a dominant "mineral-type" spectrum were 0.85 m2 g-1 and 0.73 m2 g-1, respectively and for water samples with a dominant "algae-type" spectrum were 0.64 m2 g-1 and 0.52 m2 g-1, respectively.

  4. Northeastern Exterior, Northwestern Exterior, & Southwestern Exterior Elevations, Northeastern Interior, ...

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

    Northeastern Exterior, Northwestern Exterior, & Southwestern Exterior Elevations, Northeastern Interior, Southeastern Interior, & Southwestern Interior Elevations, Floor Plan, and Eastern Corner Detail - Manatoc Reservation, Vale Edge Adirondack, 1075 Truxell Road, Peninsula, Summit County, OH

  5. Early Triassic geologic history of northeastern Nevada

    SciTech Connect

    Paull, R.K.; Paull, R.A.

    1986-08-01

    Conodont biostratigraphic and lithostratigraphic studies of Lower Triassic rocks in northeastern Elko County, Nevada, and adjacent parts of Idaho and Utah provide new information about regional geologic history. A sequential summary of Early Triassic events in this area follows: (1) rapid transgression of the Griesbachian sea to limiting barriers on the south (Oquirrh-Uinta axis) and west (Humboldt highland.). (2) Although the initial Triassic transgression may have persisted farther south and west than present-day evidence indicates, a period of progradation during the Dienerian limited marine sedimentation to northeastern-most Nevada and adjacent states. (3) In Smithian time, a widespread transgression spilled south and west over the earliest Triassic basin margin. (4) The southward flood is characterized by locally spectacular basal conglomerates followed by shallow marine deposits of the Thaynes Formation. (5) The transgression to the west was facilitated by tectonic removal of the restrictive barrier during the Smithian. This resulted in a slope-basin environment that accumulated a thick sequence of shale and calcareous siltstone with interbeds of turbidite conglomerates, olistostromes, and exotic blocks derived from Permian formations in northern Nevada or adjacent Idaho. (6) During a regional progradation in early Spathian time, marine conditions persisted in northeastern Nevada. (7) A final depositional episode is documented by the progressive westward spread of carbonate rocks of the Thaynes Formation. (8) Withdrawal of Triassic seas from northeast Nevada occurred post-latest Early Triassic, since a carbonate sequence of more than 300 m overlies the youngest dated interval.

  6. Organic-geochemical proxies of sea surface temperature in surface sediments of the tropical eastern Indian Ocean

    NASA Astrophysics Data System (ADS)

    Chen, Wenwen; Mohtadi, Mahyar; Schefuß, Enno; Mollenhauer, Gesine

    2014-06-01

    In this study we reconstruct sea surface temperatures (SSTs) using two lipid-based biomarker proxies (alkenone unsaturation index U37K‧ and TEX86 index based on glycerol dibiphytanyl glycerol tetraethers) in 36 surface sediment samples from the Indonesian continental margin off west Sumatra and south of Java and the Lesser Sunda Islands. Comparison of measured temperatures (World Ocean Atlas 09) to reconstructed temperatures suggests that SST estimates based on U37K‧ reflect the SE monsoon SST in the upwelling area south of Java and the Lesser Sunda Islands. Estimates based on TEX86 using the calibration for temperatures >20 °C (TEX86H) are up to 2 °C lower than U37K‧-based SSTs. This offset is possibly related to either one or a combination of two factors: (i) the depth habitats of the source organisms and (ii) different seasonal production and/or seasonality of export associated with phytoplankton blooming triggered by primary productivity. In the non-upwelling area off west Sumatra, the alkenone-based SSTs are cooler than measured temperatures during the entire year, likely reflecting the limitations of the U37K‧ proxy beyond 28 °C, while reconstructed temperatures based on TEX86H are consistent with mean annual SST.

  7. Volcanology and eruptive styles of Barren Island: an active mafic stratovolcano in the Andaman Sea, NE Indian Ocean

    NASA Astrophysics Data System (ADS)

    Sheth, Hetu C.; Ray, Jyotiranjan S.; Bhutani, Rajneesh; Kumar, Alok; Smitha, R. S.

    2009-11-01

    Barren Island (India) is a relatively little studied, little known active volcano in the Andaman Sea, and the northernmost active volcano of the great Indonesian arc. The volcano is built of prehistoric (possibly late Pleistocene) lava flows (dominantly basalt and basaltic andesite, with minor andesite) intercalated with volcaniclastic deposits (tuff breccias, and ash beds deposited by pyroclastic falls and surges), which are exposed along a roughly circular caldera wall. There are indications of a complete phreatomagmatic tephra ring around the exposed base of the volcano. A polygenetic cinder cone has existed at the centre of the caldera and produced basalt-basaltic andesite aa and blocky aa lava flows, as well as tephra, during historic eruptions (1787-1832) and three recent eruptions (1991, 1994-95, 2005-06). The recent aa flows include a toothpaste aa flow, with tilted and overturned crustal slabs carried atop an aa core, as well as locally developed tumuli-like elliptical uplifts having corrugated crusts. Based on various evidence we infer that it belongs to either the 1991 or the 1994-95 eruptions. The volcano has recently (2008) begun yet another eruption, so far only of tephra. We make significantly different interpretations of several features of the volcano than previous workers. This study of the volcanology and eruptive styles of the Barren Island volcano lays the ground for detailed geochemical-isotopic and petrogenetic work, and provides clues to what the volcano can be expected to do in the future.

  8. NEAMTWS-ECTE1: The First Enlarged Communication Test Exercise of the Tsunami Early Warning and Mitigation System in the North-eastern Atlantic, the Mediterranean and connected seas

    NASA Astrophysics Data System (ADS)

    Necmioglu, O.; Rudloff, A.; Matias, L. M.; Schindele, F.; Comoglu, M.; Meral Ozel, N.

    2012-04-01

    During the seventh session of the Intergovernmental Coordination Group for the Tsunami Early Warning and Mitigation System in the North-eastern Atlantic, the Mediterranean and connected seas (ICG/NEAMTWS) held in Paris, France, from 23 to 25 November 2010, a task team on Communication Test and Tsunami Exercises (TT-CT&TE) was established. The task team was responsible for the preparation and conduct of the First Enlarged Communication Test Exercise (NEAMTWS-ECTE1) and the organization of its assessment. The aim of the test exercise was to refine procedures for testing the communication of tsunami alert messages between National Tsunami Warning Centres and all Tsunami Warning Focal Points (TWFPs), including speed and availability within NEAM region. Earlier small size tests, conducted during the previous intersessional period, highlighted the importance of having other communication method like Global Telecommunication System (GTS), and therefore the utilization of GTS during the NEAMTWS-ECTE1 was another aim of the exercise. NEAMTWS-ECTE1 was conducted on 10 August 2011 with the participation of 139 end-users belonging to 42 agencies in 31 countries. A methodical and detailed analysis of the ECTE1 has been provided to ICG/NEAMTWS as a report, where 27 new recommendations were provided in order to improve all aspects of a Communication Test Exercise (CTE), ranging from the manual to the interaction with the media, but especially focusing on the technical and procedural improvements. Some technical problems during the NEAMTWS-ECTE1 have helped to clearly identify certain operational and procedural issues on which NEAMTWS should conclude some guidelines. A Small Scale Communication Test (SSCT-1) focusing on the problem areas of NEAMTWS-ECTE1 was conducted on 26 October 2011 as a follow-up exercise to consolidate the lessons learnt from NEAMTWS-ECTE1. Both NEAMTWS-ECTE-1 and SSCT-1 clearly indicates that message dissemination using fax is the least effective

  9. Simulation of the Indian Summer Monsoon Using Comprehensive Atmosphere-land Interactions, in the Absence of Two-way Air-sea Interactions

    NASA Technical Reports Server (NTRS)

    Lim, Young-Kwon; Shin, D. W.; Cocke, Steven; Kang, Sung-Dae; Kim, Hae-Dong

    2011-01-01

    Community Land Model version 2 (CLM2) as a comprehensive land surface model and a simple land surface model (SLM) were coupled to an atmospheric climate model to investigate the role of land surface processes in the development and the persistence of the South Asian summer monsoon. Two-way air-sea interactions were not considered in order to identify the reproducibility of the monsoon evolution by the comprehensive land model, which includes more realistic vertical soil moisture structures, vegetation and 2-way atmosphere-land interactions at hourly intervals. In the monsoon development phase (May and June). comprehensive land-surface treatment improves the representation of atmospheric circulations and the resulting convergence/divergence through the improvements in differential heating patterns and surface energy fluxes. Coupling with CLM2 also improves the timing and spatial distribution of rainfall maxima, reducing the seasonal rainfall overestimation by approx.60 % (1.8 mm/d for SLM, 0.7 mm/dI for CLM2). As for the interannual variation of the simulated rainfall, correlation coefficients of the Indian seasonal rainfall with observation increased from 0.21 (SLM) to 0.45 (CLM2). However, in the mature monsoon phase (July to September), coupling with the CLM2 does not exhibit a clear improvement. In contrast to the development phase, latent heat flux is underestimated and sensible heat flux and surface temperature over India are markedly overestimated. In addition, the moisture fluxes do not correlate well with lower-level atmospheric convergence, yielding correlation coefficients and root mean square errors worse than those produced by coupling with the SLM. A more realistic representation of the surface temperature and energy fluxes is needed to achieve an improved simulation for the mature monsoon period.

  10. New lucinid bivalves from shallow and deeper water of the Indian and West Pacific Oceans (Mollusca, Bivalvia, Lucinidae).

    PubMed

    Taylor, John D; Glover, Emily A

    2013-01-01

    Four new species and a new genus of lucinid bivalves are described from shallow and deeper waters in the Indian and West Pacific Oceans. The new genus Scabrilucina (subfamily Lucininae) includes the little-known Scabrilucina victorialis (Melvill, 1899) from the Arabian Sea and Scabrilucina vitrea (Deshayes, 1844) from the Andaman Sea as well as a new species Scabrilucina melvilli from the Torres Strait off northeastern Australia. Ferrocina brunei new species (Lucininae) was recovered from 60 m near oil drilling activities off Borneo; its anatomy confirmed the presence of symbiotic bacteria. Two unusual deeper water species of Leucosphaerinae are described, both species included in on-going molecular analyses; Gonimyrtea ferruginea from 400-650 m in the southwest Pacific and Myrtina reflexa from 200-825 m off Zanzibar and Madagascar. PMID:24039537

  11. New lucinid bivalves from shallow and deeper water of the Indian and West Pacific Oceans (Mollusca, Bivalvia, Lucinidae)

    PubMed Central

    Taylor, John D.; Glover, Emily A.

    2013-01-01

    Abstract Four new species and a new genus of lucinid bivalves are described from shallow and deeper waters in the Indian and West Pacific Oceans. The new genus Scabrilucina (subfamily Lucininae) includes the little-known Scabrilucina victorialis (Melvill, 1899) from the Arabian Sea and Scabrilucina vitrea (Deshayes, 1844) from the Andaman Sea as well as a new species Scabrilucina melvilli from the Torres Strait off northeastern Australia. Ferrocina brunei new species (Lucininae) was recovered from 60 m near oil drilling activities off Borneo; its anatomy confirmed the presence of symbiotic bacteria. Two unusual deeper water species of Leucosphaerinae are described, both species included in on-going molecular analyses; Gonimyrtea ferruginea from 400–650 m in the southwest Pacific and Myrtina reflexa from 200–825 m off Zanzibar and Madagascar. PMID:24039537

  12. Indian Government and Indian Education.

    ERIC Educational Resources Information Center

    Starblanket, Noel V.

    1981-01-01

    Accountability for Indian education must be shared among the chiefs and their councils, the Indian leaders at all levels, parents and students. This may be accomplished by Indian control of Indian education. Available from: Department of Educational Foundations, 5-109 Education North, University of Alberta, Edmonton, AB, Canada, T6G 2G5. (ERB)

  13. 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

  14. Wisconsin Indians.

    ERIC Educational Resources Information Center

    Lurie, Nancy Oestreich

    Wisconsin encompasses an astonishingly representative illustration of the total historical development of federal Indian policy and Indian reactions to it. Wisconsin's Indian population (at least 25,000 people) is the third largest east of the Mississippi River and offers great diversity (3 major linguistic stocks, 6 broad tribal affiliations, and…

  15. Variability of the Arabian Sea upwelling and intensity of the oxygen minimum zone over the late Pleistocene and Holocene

    NASA Astrophysics Data System (ADS)

    Gaye, Birgit; Böll, Anna; Rixen, Tim; Emeis, Kay-Christian; Ramaswamy, Venkitasubramani

    2016-04-01

    The northern Arabian Sea is one of the main oceanic regions with a permanent low oxygen layer at intermediate water depth that results in water column denitrification. While glacial/interglacial variations in the Arabian Sea oxygen minimum zone (OMZ) are relatively well studied, little is known about the spatial and temporal extent of mid-water oxygen throughout the Holocene. We compared alkenone derived sea surface temperatures of the last 25 kyrs from a core in the northern Arabian Sea with a core from the monsoonal upwelling area off Oman. The difference between the two temperature reconstructions indicates that monsoonal upwelling occurred during warm interstadials and during the entire Holocene. δ15N curves show that denitrification also matched with monsoonal upwelling. Comparison of δ15N records from different locations in the Arabian Sea reveal a Holocene shift in the location of the core OMZ from the northwestern (early Holocene) to the northeastern Arabian Sea (late Holocene). This shift was caused by (i) spatial differences in oxygen demand, caused by changes in SW- and NE-monsoon intensities and associated productivity changes, as well as (ii) changes in mid-water ventilation facilitated by sea level rise and inflow of Persian Gulf and Red Sea Water leading and changes of ventilation by Indian Ocean Central Water .

  16. A prominent pattern of year-to-year variability in Indian Summer Monsoon Rainfall.

    PubMed

    Mishra, Vimal; Smoliak, Brian V; Lettenmaier, Dennis P; Wallace, John M

    2012-05-01

    The dominant patterns of Indian Summer Monsoon Rainfall (ISMR) and their relationships with the sea surface temperature and 850-hPa wind fields are examined using gridded datasets from 1900 on. The two leading empirical orthogonal functions (EOFs) of ISMR over India are used as basis functions for elucidating these relationships. EOF1 is highly correlated with all India rainfall and El Niño-Southern Oscillation indices. EOF2 involves rainfall anomalies of opposing polarity over the Gangetic Plain and peninsular India. The spatial pattern of the trends in ISMR from 1950 on shows drying over the Gangetic Plain projects onto EOF2, with an expansion coefficient that exhibits a pronounced trend during this period. EOF2 is coupled with the dominant pattern of sea surface temperature variability over the Indian Ocean sector, which involves in-phase fluctuations over the Arabian Sea, the Bay of Bengal, and the South China Sea, and it is correlated with the previous winter's El Niño-Southern Oscillation indices. The circulation anomalies observed in association with fluctuations in the time-varying indices of EOF1 and EOF2 both involve distortions of the low-level monsoon flow. EOF1 in its positive polarity represents a southward deflection of moist, westerly monsoon flow from the Arabian Sea across India, resulting in a smaller flux of moisture to the Himalayas. EOF2 in its positive polarity represents a weakening of the monsoon trough over northeastern India and the westerly monsoon flow across southern India, reminiscent of the circulation anomalies observed during break periods within the monsoon season. PMID:22529372

  17. A palaeomagnetic reconnaissance of northeastern Baluchistan, Pakistan

    NASA Astrophysics Data System (ADS)

    Klootwijk, Chris T.; Nazirullah, Russel; de Jong, Kees A.; Ahmed, Habib

    1981-01-01

    A total of 560 samples from three areas in northeastern Baluchistan (the southern Sulaiman Range, the central Loralai Range, and the northern Kirthar Range) were analyzed using thermal demagnetization techniques. Thirteen formations of late Palaeozoic to early Tertiary age were studied palaeomagnetically. Inclinations of the obtained results show a general affinity with the Indian apparent polar wander path. Deviating declinations from the Loralai Range indicate a clockwise rotation over 50° with respect to the Indian shield. Secondary magnetization components probably of late Palaeocene to early Eocene age were consistently present in the samples from the Kirthar Range and the Sulaiman Range but were not observed in samples from the Loralai Range. Acquisition of these components is attributed to crustal upwarping during the Palaeocene, which is tentatively related to initial collision of continental Indo-Pakistan with an island arc off south central Asia. The Baluchistan data support recent palaeomagnetic results from the Indus-Tsangpo suture zone in Ladakh (NW Himalaya), which indicate that such an initial collision took place at very low northern palaeolatitudes.

  18. An Indian-controlled mental health program.

    PubMed

    Ostendorf, D; Hammerschlag, C A

    1977-09-01

    The control of health care programs for American Indians is shifting slowly from the federal government to the tribes. In 1971 the Apaches began operating a community mental health center on a reservation in northeastern Arizona. The tribal council appointed a 14-member board to administer the center; a majority of the members were Apaches. The board then hired an executive director who was not an Indian. There were 15 professional and paraprofessional staff members; 12 were Apaches or other Indians. In January 1976 the tribal council fired the director and disbanded the board of directors, although the clinic continued operation. The authors discuss sociocultural factors that influenced the center's development and give several reasons for the center's problems, including the general expectation that agencies run by Indians will not be successful. PMID:892727

  19. Indian Reservations

    ERIC Educational Resources Information Center

    Weewish Tree, 1974

    1974-01-01

    Answers to questions asked by junior high school students about American Indian reservations are given. The areas covered include nearly every facet of reservation life from the first Federal issuance of particles of land to the American Indians to present conditions on the reservations. (AH)

  20. Indian Legends.

    ERIC Educational Resources Information Center

    Gurnoe, Katherine J.; Skjervold, Christian, Ed.

    Presenting American Indian legends, this material provides insight into the cultural background of the Dakota, Ojibwa, and Winnebago people. Written in a straightforward manner, each of the eight legends is associated with an Indian group. The legends included here are titled as follows: Minnesota is Minabozho's Land (Ojibwa); How We Got the…

  1. MISR Images Northeastern Botswana

    NASA Technical Reports Server (NTRS)

    2000-01-01

    MISR images of the Ntwetwe and Sua Pans in northeastern Botswana, acquired on August 18, 2000 (Terra orbit 3553). The left image is a color view from the vertical-viewing (nadir) camera. On the right is a composite of red band imagery in which the 45-degree aft camera data are displayed in blue, 45-degree forward as green, and vertical as red. This combination causes wet areas to appear blue because of the glint-like reflection from water and damp surfaces. Clouds are visible in the upper left corner and right center of each image. The clouds look peculiar in the multi-angle view because geometric parallax resulting from their elevation above the surface causes a misregistration of the individual images making up the composite. This stereoscopic effect provides a way of distinguishing clouds from bright surfaces.

    The images are approximately 250 kilometers across. Ntwetwe and Sua pans are closed interior basins that catch rainwater and surface runoff during the wet season. Seasonal lakes form that may reach several meters in depth. During the dry season the collected waters rapidly evaporate leaving behind dissolved salts that coat the surface and turn it bright ('sua' means salt). The mining town of Sowa is located where the Sua Spit (a finger of grassland extending into the pan) attaches to the shore. Sowa represents headquarters for a JPL contingent carrying out MISR field experiments using the evaporite surface and the grasslands as targets and for Botswana scientists studying migration of groundwaters beneath the pans and surrounding areas. These efforts support the Southern Africa Regional Science Initiative (SAFARI-2000), which is now underway.

    MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology.

    For more information: http://www-misr.jpl.nasa.gov

  2. Re-description of two species of the cardinalfish genus Archamia (Teleostei: Apogonidae) from the Red Sea and Western Indian Ocean.

    PubMed

    Gon, Ofer; Gouws, Gavin; Mwale, Monica; Mwaluma, James

    2013-01-01

    The cardinalfishes Archamia bilineata and A. pallida were originally described from a small number of specimens collected in the Gulf of Aqaba, Red Sea and Oman, respectively. Both species are re-described using specimens collected recently in Yemen and Kenya, including the first known adult of A. pallida. These new collections increased the geographical range of both species considerably. Differences between the two populations now known for each of the species are discussed. PMID:24614490

  3. Varying responses to Indian monsoons during the past 220 kyr recorded in deep-sea sediments in inner and outer regions of the Gulf of Aden

    NASA Astrophysics Data System (ADS)

    Isaji, Yuta; Kawahata, Hodaka; Ohkouchi, Naohiko; Ogawa, Nanako O.; Murayama, Masafumi; Inoue, Kazuki; Tamaki, Kensaku

    2015-11-01

    Although the climate in the Arabian Sea is controlled primarily by the southwest monsoon, the southwest monsoon has little influence in the Gulf of Aden. To examine the different responses to monsoons between the Gulf of Aden and areas outside the gulf, a comprehensive data set of bulk organic and inorganic geochemistry, sea surface temperature, and δ15N of pheopigments was obtained from deep-sea sediment cores recovered from inner and outer regions of the gulf. The results indicated that during the past 220 kyr, the influence of the southwest monsoon was stronger in the outer region of the gulf than in the inner region, which implies that the southwest monsoon trajectory has not changed substantially during that time period. Furthermore, influxes of O2-depleted water from the Southern Ocean and the lateral advection of upwelled seawater also had limited influence in the inner region. In contrast, concentrations of lithogenic materials transported by the southwest monsoon were similar in the two regions. δ15N of pheopigments indicated that during the last glacial maximum, the southwest monsoon was weaker and the northeast monsoon was stronger than at present. A stronger southwest monsoon during interglacials enhanced primary productivity and may have caused anoxic conditions to develop in the Arabian Sea, as indicated by redox proxies in the outer region. Anoxic conditions also formed during MIS 3, but no increase in the primary productivity is indicated; therefore, another mechanism, such as an influx of O2-depleted water from the Southern Ocean, may have been the cause.

  4. Indian Summer

    SciTech Connect

    Galindo, E.

    1997-08-01

    This paper focuses on preserving and strengthening two resources culturally and socially important to the Shoshone-Bannock Indian Tribe on the Fort Hall Reservation in Idaho; their young people and the Pacific-Northwest Salmon. After learning that salmon were not returning in significant numbers to ancestral fishing waters at headwater spawning sites, tribal youth wanted to know why. As a result, the Indian Summer project was conceived to give Shoshone-Bannock High School students the opportunity to develop hands-on, workable solutions to improve future Indian fishing and help make the river healthy again. The project goals were to increase the number of fry introduced into the streams, teach the Shoshone-Bannock students how to use scientific methodologies, and get students, parents, community members, and Indian and non-Indian mentors excited about learning. The students chose an egg incubation experiment to help increase self-sustaining, natural production of steelhead trout, and formulated and carried out a three step plan to increase the hatch-rate of steelhead trout in Idaho waters. With the help of local companies, governmental agencies, scientists, and mentors students have been able to meet their project goals, and at the same time, have learned how to use scientific methods to solve real life problems, how to return what they have used to the water and land, and how to have fun and enjoy life while learning.

  5. Novel terpenoids from the West Indian sea whip Pseudopterogorgia elisabethae (Bayer). Elisapterosins A and B: rearranged diterpenes possessing an unprecedented cagelike framework.

    PubMed

    Rodríguez, A D; Ramírez, C; Rodríguez, I I; Barnes, C L

    2000-03-10

    Four diterpenes and a nor-diterpenoid, all of which possess unusual carbocyclic skeletons, were isolated from the hexane solubles of the West Indian gorgonian Pseudopterogorgia elisabethae. The structures and relative configurations of novel metabolites elisabethin D (2), elisabethin D acetate (3), 3-epi-elisabanolide (5), elisapterosin A (6), and elisapterosin B (7) were elucidated by interpretation of overall spectral data, which included 2D NMR correlation methods, IR, UV, and accurate mass measurements (HREI-MS and HRFAB-MS), chemical reactions, and X-ray diffraction analyses. The tetracyclic carbon skeleton of the elisapterosins is undescribed and constitutes a new class of C(20) rearranged diterpenes. Elisapterosin B displays strong in vitro anti-tuberculosis activity. PMID:10814100

  6. 76 FR 29670 - Fisheries of the Northeastern United States; Summer Flounder Fishery; Quota Transfer

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-23

    ... (76 FR 23206). The difference is 590 lb (268 kg) less of summer flounder to be transferred; therefore..., Scup, and Black Sea Bass Fishery Management Plan, which was published on December 17, 1993 (58 FR 65936... Atmospheric Administration 50 CFR Part 648 RIN 0648-XA403 Fisheries of the Northeastern United States;...

  7. 76 FR 23206 - Fisheries of the Northeastern United States; Summer Flounder Fishery; Quota Transfer

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-26

    ... Sea Bass Fishery Management Plan, which was published on December 17, 1993 (58 FR 65936), provided a... included in the quota transfer effective April 4, 2011 (76 FR 19277). This correction accounts for 2,805 lb... Northeastern United States; Summer Flounder Fishery; Quota Transfer AGENCY: National Marine Fisheries...

  8. 76 FR 17032 - Fisheries of the Northeastern United States; Summer Flounder Fishery; Quota Transfer

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-28

    ... Sea Bass Fishery Management Plan, which was published on December 17, 1993 (58 FR 65936), provided a... Northeastern United States; Summer Flounder Fishery; Quota Transfer AGENCY: National Marine Fisheries Service... and 2011 commercial summer flounder quotas to the Commonwealth of Virginia. Vessels were authorized...

  9. 77 FR 14481 - Fisheries of the Northeastern United States; Summer Flounder Fishery; Quota Transfer

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-12

    ... Flounder, Scup, and Black Sea Bass Fishery Management Plan, which was published on December 17, 1993 (58 FR... Northeastern United States; Summer Flounder Fishery; Quota Transfer AGENCY: National Marine Fisheries Service... commercial summer flounder quota to the Commonwealth of Virginia. By this action, NMFS adjusts the quotas...

  10. 78 FR 25003 - Fisheries of the Northeastern United States; Summer Flounder Fishery; Quota Transfer

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-29

    ..., Scup, and Black Sea Bass Fishery Management Plan, which was published on December 17, 1993 (58 FR 65936... Northeastern United States; Summer Flounder Fishery; Quota Transfer AGENCY: National Marine Fisheries Service... commercial summer flounder quota to the Commonwealth of Virginia and to the State of Rhode Island; and...

  11. 78 FR 66857 - Fisheries of the Northeastern United States; Summer Flounder Fishery; Quota Transfer

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-07

    ..., Scup, and Black Sea Bass Fishery Management Plan, which was published on December 17, 1993 (58 FR 65936... Northeastern United States; Summer Flounder Fishery; Quota Transfer AGENCY: National Marine Fisheries Service... summer flounder quota to the State of Connecticut. NMFS is adjusting the quotas and announcing...

  12. 77 FR 73556 - Fisheries of the Northeastern United States; Summer Flounder Fishery; Quota Transfer

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-11

    ..., Scup, and Black Sea Bass Fishery Management Plan, which was published on December 17, 1993 (58 FR 65936... Northeastern United States; Summer Flounder Fishery; Quota Transfer AGENCY: National Marine Fisheries Service... summer flounder quota to the State of Connecticut. NMFS is adjusting the quotas and announcing...

  13. 77 FR 69567 - Fisheries of the Northeastern United States; Summer Flounder Fishery; Quota Transfer

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-20

    ..., Scup, and Black Sea Bass Fishery Management Plan, which was published on December 17, 1993 (58 FR 65936... Northeastern United States; Summer Flounder Fishery; Quota Transfer AGENCY: National Marine Fisheries Service... commercial summer flounder quota to the State of Rhode Island. NMFS is adjusting the quotas and...

  14. 75 FR 76925 - Fisheries of the Northeastern United States; Summer Flounder Fishery; Quota Transfer

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-10

    ... Flounder, Scup, and Black Sea Bass Fishery Management Plan, which was published on December 17, 1993 (58 FR... Northeastern United States; Summer Flounder Fishery; Quota Transfer AGENCY: National Marine Fisheries Service... summer flounder quota to the Commonwealth of Virginia. By this action, NMFS adjusts the quotas...

  15. 78 FR 76765 - Fisheries of the Northeastern United States; Summer Flounder Fishery; Quota Transfer

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-19

    ..., Scup, and Black Sea Bass Fishery Management Plan, which was published on December 17, 1993 (58 FR 65936... Northeastern United States; Summer Flounder Fishery; Quota Transfer AGENCY: National Marine Fisheries Service... commercial summer flounder quota to the State of Connecticut. NMFS is adjusting the quotas and announcing...

  16. 78 FR 9849 - Fisheries of the Northeastern United States; Summer Flounder Fishery; Quota Transfer

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-12

    ... Sea Bass Fishery Management Plan, which was published on December 17, 1993 (58 FR 65936), provided a... Northeastern United States; Summer Flounder Fishery; Quota Transfer AGENCY: National Marine Fisheries Service... of its 2012 commercial summer flounder quota to the Commonwealth of Virginia. NMFS is adjusting...

  17. 77 FR 25103 - Fisheries of the Northeastern United States; Summer Flounder Fishery; Quota Transfer

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-27

    ..., Scup, and Black Sea Bass Fishery Management Plan, which was published on December 17, 1993 (58 FR 65936... Northeastern United States; Summer Flounder Fishery; Quota Transfer AGENCY: National Marine Fisheries Service... commercial summer flounder quota to the Commonwealth of Virginia. NMFS is adjusting the quotas and...

  18. Joint spatiotemporal variability of global sea surface temperatures and global Palmer drought severity index values

    USGS Publications Warehouse

    Apipattanavis, S.; McCabe, G.J.; Rajagopalan, B.; Gangopadhyay, S.

    2009-01-01

    Dominant modes of individual and joint variability in global sea surface temperatures (SST) and global Palmer drought severity index (PDSI) values for the twentieth century are identified through a multivariate frequency domain singular value decomposition. This analysis indicates that a secular trend and variability related to the El Niño–Southern Oscillation (ENSO) are the dominant modes of variance shared among the global datasets. For the SST data the secular trend corresponds to a positive trend in Indian Ocean and South Atlantic SSTs, and a negative trend in North Pacific and North Atlantic SSTs. The ENSO reconstruction shows a strong signal in the tropical Pacific, North Pacific, and Indian Ocean regions. For the PDSI data, the secular trend reconstruction shows high amplitudes over central Africa including the Sahel, whereas the regions with strong ENSO amplitudes in PDSI are the southwestern and northwestern United States, South Africa, northeastern Brazil, central Africa, the Indian subcontinent, and Australia. An additional significant frequency, multidecadal variability, is identified for the Northern Hemisphere. This multidecadal frequency appears to be related to the Atlantic multidecadal oscillation (AMO). The multidecadal frequency is statistically significant in the Northern Hemisphere SST data, but is statistically nonsignificant in the PDSI data.

  19. Northeastern Summer Electricity Market Alert

    EIA Publications

    2013-01-01

    The National Weather Service declared an excessive-heat warning for much of the Mid-Atlantic and northeastern United States, including major electric markets covering Philadelphia, Boston, Washington, D.C., and New York City. This report highlights the wholesale electricity market activity occurring in response to the higher-than-normal electricity demand caused by the heat wave.

  20. 1.2 million years of aeolian activity in northwestern Western Australian recorded in a deep-sea core in the eastern Indian Ocean

    NASA Astrophysics Data System (ADS)

    Temmesfeld, Felix; Stuut, Jan-Berend; Bassinot, Franck; Heslop, David; De Deckker, Patrick

    2015-04-01

    There is no continuous record of aridity from the Australian continent and we are presenting here, for the first time, a record of aeolian activity for northwestern Western Australia. Our data are based on a 32m long deep-sea core taken offshore North West Cape, the northwestern tip of Western Australia. Our data rely on 2 adjacent studies: (a) a complete XRF scan of the core which provide elemental ratios which are translated into an aeolian component as well as a fluvial discharge-to-sea component. The first one relates to periods of aridity inland Australia, whereas the second one is interpreted as river discharge during periods of monsoonal activity; (b) a close examination of grain size analyses and observations of wind-blown quartz grains found in close to 600 samples taken from the core. Our results clearly show a cyclic record of alternating dry and wet periods spanning the last 1.2 million years. Our findings also indicate that monsoonal activity as well as desertification were already in place in northern Australia so long ago, and this has clear implications for the evolution of the arid zone biota, associated fire activities and geomorphological features in northern Australia.

  1. Indian Orphanages.

    ERIC Educational Resources Information Center

    Holt, Marilyn Irvin

    With their traditional tribal and kinship ties, Native Americans had lived for centuries without the concept of an unwanted child. But besieged by reservation life and boarding school acculturation, many tribes, with the encouragement of whites, came to accept the need for orphanages. This book tells the story of Indian orphanages within the…

  2. Sea surface temperatures in the central southern Indian Ocean over the period 1790 to 2007 inferred from two monthly resolved Sr/Ca and oxygen isotope records

    NASA Astrophysics Data System (ADS)

    Zinke, J.; Wassenburg, J.; Hardman, E.

    2009-04-01

    We obtained two monthly resolved Sr/Ca records from Rodrigues island (Mauritius) located in the trade wind belt of the central southern Indian Ocean. The longest core was obtained at a nearshore fringing reef and covers the period 1790-2005. This coral records surface air temperatures from the local weather station available from 1950 to the present. The most remarkable signal is a slight cooling after the 1950's. The second core was obtained from the open ocean and records a long-term warming trend between 1947 to 2007. The warming accelerated after the late 1970's in agreement with instrumental data. The oxygen isotope record is affected by salinity variations and shows a strong freshening trend after the late 1970's. The freshening trend is probably related to advection of low salinity waters with the South Equatorial Current and/or increased cyclonicity. We will discuss our results in light of interannual and decadal variability and present long-term seawater monitoring data.

  3. Satellite-Based Surface Heat Budgets and Sea Surface Temperature Tendency in the Tropical Eastern Indian and Western Pacific Oceans for the 1997/98 El Nino and 1998/99 La Nina

    NASA Technical Reports Server (NTRS)

    Chou, Shu-Hsien; Chou, Ming-Dah; Chan, Pui-King; Lin, Po-Hsiung

    2002-01-01

    The 1997/98 is a strong El Nino warm event, while the 1998/99 is a moderate La Nina cold event. We have investigated surface heat budgets and sea surface temperature (SST) tendency for these two events in the tropical western Pacific and eastern Indian Oceans using satellite-retrieved surface radiative and turbulent fluxes. The radiative fluxes are taken from the Goddard Satellite-retrieved Surface Radiation Budget (GSSRB), derived from radiance measurements of the Japanese Geostationary Meteorological Satellite 5. The GSSRB covers the domain 40 deg S - 4 deg N, 90 deg E-17 deg W and a period from October 1997 to December 2000. The spatial resolution is 0.5 deg x 0.5 deg lat-long and the temporal resolution is 1 day. The turbulent fluxes are taken from Version 2 of the Goddard Satellite-based Surface Turbulent Fluxes (GSSTF-2). The GSSTF-2 has a spatial resolution of 1 deg x 1 deg lat-long over global Oceans and a temporal resolution of 1 day covering the period July 1987-December 2000. Daily turbulent fluxes are derived from the S S M (Special Sensor Microwave/Imager) surface wind and surface air humidity, and the SST and 2-m air temperature of the NCEP/NCAR reanalysis, using a stability-dependent bulk flux algorithm. The changes of surface heat budgets, SST and tendency, cloudiness, wind speed, and zonal wind stress of the 1997/98 El Nino relative to the1998/99 La Nina for the northern winter and spring seasons are analyzed. The relative changes of surface heat budgets and SST tendency of the two events are quite different between the tropical eastern Indian and western Pacific Oceans. For the tropical western Pacific, reduced solar heating (more clouds) is generally associated with decreased evaporative cooling (weaker winds), and vise versa. The changes in evaporative cooling over-compensate that of solar heating and dominate the spatial variability of the changes in net surface heating. Both solar heating and evaporative cooling offset each other to reduce

  4. Two flavors of the Indian Ocean Dipole

    NASA Astrophysics Data System (ADS)

    Endo, Satoru; Tozuka, Tomoki

    2015-07-01

    The Indian Ocean Dipole (IOD) is known as a climate mode in the tropical Indian Ocean accompanied by negative (positive) sea surface temperature (SST) anomalies over the eastern (western) pole during its positive phase. However, the western pole of the IOD is not always covered totally by positive SST anomalies. For this reason, the IOD is further classified into two types in this study based on SST anomalies in the western pole. The first type (hereafter "canonical IOD") is associated with negative (positive) SST anomalies in the eastern (central to western) tropical Indian Ocean. The second type (hereafter "IOD Modoki"), on the other hand, is associated with negative SST anomalies in the eastern and western tropical Indian Ocean and positive SST anomalies in the central tropical Indian Ocean. Based on composite analyses, it is found that easterly wind anomalies cover the whole equatorial Indian Ocean in the canonical IOD, and as a result, positive rainfall anomalies are observed over East Africa. Also, due to the basin-wide easterly wind anomalies, the canonical IOD is accompanied by strong sea surface height (SSH) anomalies. In contrast, zonal wind anomalies converge in the central tropical Indian Ocean in the IOD Modoki, and no significant precipitation anomalies are found over East Africa. Also, only weak SSH anomalies are seen, because equatorial downwelling anomalies induced by westerly wind anomalies in the west are counteracted by equatorial upwelling anomalies caused by easterly wind anomalies in the east.

  5. Two flavors of the Indian Ocean Dipole

    NASA Astrophysics Data System (ADS)

    Endo, Satoru; Tozuka, Tomoki

    2016-06-01

    The Indian Ocean Dipole (IOD) is known as a climate mode in the tropical Indian Ocean accompanied by negative (positive) sea surface temperature (SST) anomalies over the eastern (western) pole during its positive phase. However, the western pole of the IOD is not always covered totally by positive SST anomalies. For this reason, the IOD is further classified into two types in this study based on SST anomalies in the western pole. The first type (hereafter "canonical IOD") is associated with negative (positive) SST anomalies in the eastern (central to western) tropical Indian Ocean. The second type (hereafter "IOD Modoki"), on the other hand, is associated with negative SST anomalies in the eastern and western tropical Indian Ocean and positive SST anomalies in the central tropical Indian Ocean. Based on composite analyses, it is found that easterly wind anomalies cover the whole equatorial Indian Ocean in the canonical IOD, and as a result, positive rainfall anomalies are observed over East Africa. Also, due to the basin-wide easterly wind anomalies, the canonical IOD is accompanied by strong sea surface height (SSH) anomalies. In contrast, zonal wind anomalies converge in the central tropical Indian Ocean in the IOD Modoki, and no significant precipitation anomalies are found over East Africa. Also, only weak SSH anomalies are seen, because equatorial downwelling anomalies induced by westerly wind anomalies in the west are counteracted by equatorial upwelling anomalies caused by easterly wind anomalies in the east.

  6. Wyoming Indians, Unit II.

    ERIC Educational Resources Information Center

    Robinson, Terry

    This unit on Wyoming Indians provides concepts, activities, Indian stories, and resources for elementary school students. Indian values and contributions are summarized. Concepts include the incorrectness of the term "Indian," the Indians' democratic society and sophisticated culture, historical events, and conflicts with whites over the land.…

  7. Urban Indian Project.

    ERIC Educational Resources Information Center

    Greymountain, Gus; And Others

    The second of a 2 phase study, this project provided information for the non-Indian population about problems and needs of urban American Indians. Phase I (1971) discussed urban Indian experiences and trends; compared differences and highlighted issues of Indian urbanization. Phase II focused entirely on the urban Indian community. The thrust was…

  8. The main issues affecting coasts of the Indian and western Pacific Oceans: a meta-analysis from Seas at the Millennium.

    PubMed

    Sheppard, C

    2001-12-01

    A review of the world oceans in three volumes by 365 scientists, provides scope for several 'meta-analyses' of the main problems affecting over 100 areas in the year 2000. This article summarises the main issues affecting a sub-set of the reviewed areas, covering Asian, African and Arabian countries dealt with in Volume 2, which included over 50 articles. From all issues raised, assessment is made of the nature of the major ones, including evaluation of reasons why so many of them remain important issues after so much attention to them. These include long standing problems, several problems more newly flagged as becoming particularly important, the issue of global warming and no less than three related issues connected with fishing and over exploitation. One or two issues such as industrial pollution and sewage, previously considered of almost universal concern, almost traditional pollution issues even, continue to feature strongly for some countries, but while these were almost always referred to in Seas chapters, by and large these categories appear not to be the most pressing of issues today, except in localized areas (albeit areas where huge numbers of people live). Perhaps other issues have simply taken over. They are excluded from this article. PMID:11827106

  9. Clay Mineralogical Records in Sediments along the Shelf Break of the Eastern Andaman Sea

    NASA Astrophysics Data System (ADS)

    Bunsomboonsakul, S.; Liu, Z.; Sompongchaiyakul, P.; Snidvongs, A.; Krastel, S.

    2012-12-01

    The Andaman Sea as part of the northeastern Indian Ocean is located between the Irrawaddy delta coast of Myanmar in the north and Sumatra and the Malacca Strait in the south. Distribution of sediments in the Andaman Sea is strongly influenced by two prevailing monsoon seasons: northeast (November-April) and southwest (May-October) monsoons. However, the sedimentation process is little known. In this study, clay mineralogy has been inquired to indicate sediment transportation and provenance of the Andaman Sea sediments. Two sediment cores from offshore and surface sediments from two nearshore locations in the Andaman Sea were studied. The cores of 1.58 m (MASS-III-07) and 1.50 m (MASS-III-10) long were collected from a flat-top plateau protruded along the Andaman Sea shelf break off the west coast of Thailand (604 m and 632 m water depth, respectively). The plateau has been found during the MASS project in 2007. The surface sediments were collected from off Thailand coast to represent the middle part source and off Myanmar coast to represent the northern part source, respectively. Semiquantitative analyses of clay minerals were performed using X-ray diffraction (XRD) to document clay mineralogical composition and distribution, and to reconstruct the chronological oceanic processes. The preliminary results reveal that the cores contain high smectite (65-79%) and kaolinite (9-18%), and low illite and chlorite contents (<10%). Although clay mineral contents of the two cores shows similar average compositions, the vertical profiles of distribution are displayed reversely particularly for smectite, kaolinite and illite. The results from core sediments suggest that the sediment transport in this area was strongly controlled by the plateau in addition to the current direction. In comparison of clay mineral compositions of the two cores with the surface sediments, it is implied that the potential terrigenous sediment input to the Andaman Sea was likewise from Myanmar than

  10. Student Opinion Surveys at Northeastern University.

    ERIC Educational Resources Information Center

    Bajdek, Anthony J.; Kim, Sungwoo

    1999-01-01

    Presents the 15-year story of the student affairs research operation at Northeastern University, covering the initial buildup, the demise due to institutional downsizing, and the resurrection. (Author)

  11. New High-Resolution δ13C and δ18O Records for the Late Paleocene (59-56 Ma) from Deep Sea Drilling Project Leg 22, Site 215, Central Indian Ocean Basin

    NASA Astrophysics Data System (ADS)

    Theodorou, M. C.; Pekar, S. F.; Ramirez, J.

    2012-12-01

    High-resolution benthic foraminiferal stable isotope records were developed from upper Paleocene strata from Deep Sea Drilling Project Leg 22 Site 215 to investigate paleoceanographic changes during the lead up to the Paleocene Eocene Thermal Maximum (PETM). Site 215 was drilled at a depth of 5,309 meters (paleodepth of ~3,300 meters) and is located in the Central Indian Basin, west of Ninetyeast Ridge (8°07.30'S, 86°47.50'E). Late Paleocene strata are composed of nannofossil ooze recovered at relatively shallow depths (between 82 and 149 mbsf). This resulted in excellent preservation of the foraminiferal tests. Stable isotope records were developed using benthic foraminiferal species Cibicidoides dayi, C. hyphalus, and Oridorsalis umbonatus, with the δ18O data corrected for vital effects for each genus. Age resolution between samples range from 5 to 10 kyr. As seen in other isotopic records, a long-term decrease in both δ13C and δ18O occurs between 58 to 56 Ma, leading up to the PETM. A number of δ13C excursions of up to 1 ‰ occur between 56.0 and 56.5 Ma, of which two coincide with δ18O excursions of up to 0.6‰ or about 2.5°C. These δ13C excursions occur at approximately 20 kyr intervals, which we interpret could be related to the precessional cycle. Comparing to the other high-resolution isotopic record from Site 1209, δ13C isotopes are heavier at Site 215 than at Site 1209 between 58 and 56.5 Ma, becoming lighter between 56.5 and 56 Ma. This suggests a change in the source of deep-waters during this time interval. We speculate that deep-water production switched from a Southern Ocean to possibly a northern hemisphere source.

  12. Deglacial Indian monsoon failure and North Atlantic stadials linked by Indian Ocean surface cooling

    NASA Astrophysics Data System (ADS)

    Tierney, Jessica E.; Pausata, Francesco S. R.; Demenocal, Peter

    2016-01-01

    The Indian monsoon, the largest monsoon system on Earth, responds to remote climatic forcings, including temperature changes in the North Atlantic. The monsoon was weak during two cool periods that punctuated the last deglaciation--Heinrich Stadial 1 and the Younger Dryas. It has been suggested that sea surface cooling in the Indian Ocean was the critical link between these North Atlantic stadials and monsoon failure; however, based on existing proxy records it is unclear whether surface temperatures in the Indian Ocean and Arabian Sea dropped during these intervals. Here we compile new and existing temperature proxy data from the Arabian Sea, and find that surface temperatures cooled whereas subsurface temperatures warmed during both Heinrich Stadial 1 and the Younger Dryas. Our analysis of model simulations shows that surface cooling weakens the monsoon winds and leads to destratification of the water column and substantial subsurface warming. We thus conclude that sea surface temperatures in the Indian Ocean are indeed the link between North Atlantic climate and the strength of the Indian monsoon.

  13. An Indian Ocean precursor for Indian summer monsoon rainfall variability

    NASA Astrophysics Data System (ADS)

    Sreejith, O. P.; Panickal, S.; Pai, S.; Rajeevan, M.

    2015-11-01

    The Indian summer monsoon rainfall (ISMR) depicts large interannual variability strongly linked with El Niño-Southern Oscillation (ENSO). However, many of the El Niño years were not accompanied by deficient ISMR. The results from the study reveal the significant role of coupled air-sea interaction over the tropical Indian Ocean (IO) in modifying the ENSO-ISMR association. The IO warm water volume (WWV), a measure of heat content variations in the equatorial IO has strong influence on ISMR. A deepening (shoaling) of thermocline in the eastern equatorial IO (EEIO) during late boreal spring (April-May) accompanied by increase (decrease) in WWV anomalies weaken (enhance) the ISMR by enhancing (suppressing) the convection over EEIO resulting in the below (above) normal ISMR. Thus, the changes in the WWV anomalies in the EEIO along with ENSO conditions during boreal spring can be considered as a precursor for the performance of subsequent ISMR.

  14. Moccasins into Slippers: Woodlands Indian Hats, Bags, and Shoes in Tradition and Transformation.

    ERIC Educational Resources Information Center

    Phillips, Ruth B.

    1990-01-01

    In the mid-nineteenth century, an abrupt transformation occurred in textiles and other art forms of northeastern Woodlands Indians. Trade, tourism, and survival needs sparked changes in materials used and garment types produced, as well as substitution of a new vocabulary of floral imagery for "pagan" iconographic traditions. (SV)

  15. Pasture plants of the Northeastern United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Temperate humid grazing lands are an important component of the landscape of the northeastern Unites States, as well as of the economy of this region, yet unlike their European counterparts, little is known about their basic ecology. During an eight-year survey of 44 farms across the northeastern Un...

  16. Pasture Plants of the Northeastern United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This factsheet contains summary information about the most common plant species encountered in northeastern pastures. Some information, such as plant size and flowering time, comes from standard reference works. Information on frequency and abundance in northeastern pastures is derived from an eight...

  17. American Indian Sports Heritage.

    ERIC Educational Resources Information Center

    Oxendine, Joseph B.

    This book chronicles the story of sports among American Indians. Part 1 examines the nature and role of games in traditional Indian life, with five chapters on: Indian concepts of sport; ball games; foot racing; other sports; children's play; and games of chance. Part 2 looks at the emergence of Indians in modern sport, with five chapters on:…

  18. Indian Ledger Art.

    ERIC Educational Resources Information Center

    Chilcoat, George W.

    1990-01-01

    Offers an innovative way to teach mid-nineteenth century North American Indian history by having students create their own Indian Ledger art. Purposes of the project are: to understand the role played by American Indians, to reveal American Indian stereotypes, and to identify relationships between cultures and environments. Background and…

  19. Indians of the Dakotas.

    ERIC Educational Resources Information Center

    Bureau of Indian Affairs (Dept. of Interior), Washington, DC.

    A brief history of Indian tribes in the States of North and South Dakota is presented. Discussion centers around individual Indian tribes, such as Chippewas and Sioux, which are representative of early and modern Indian life in these States. A section devoted to Indians in these states today offers an indication of the present condition of the…

  20. KNOW YOUR NEVADA INDIANS.

    ERIC Educational Resources Information Center

    POEHLMAN, CHARLES H.; AND OTHERS

    THIS PUBLICATION PRESENTS THE RESULTS OF A STUDY OF THE SOCIOCULTURAL BACKGROUNDS OF THE PAIUTE, WASHOE, AND SHOSHONE INDIANS OF NEVADA. INCLUDED ARE AN OUTLINE OF GENERAL PROBLEMS PERTAINING TO INDIAN EDUCATION, SOME DISTINCT CULTURAL DIFFERENCES BETWEEN THE DOMINANT NON-INDIAN SOCIETY AND THE INDIAN SOCIETY, AND THE PREHISTORIC ASPECTS OF THE…

  1. American Indian Education Handbook.

    ERIC Educational Resources Information Center

    O'Malley, Edward, Ed.

    Written for teachers instructing both Indian and non-Indian students, the handbook provides information on American Indians in California. The handbook is presented in six chapters. Chapter 1 is devoted to terminoloy (e.g., American Indian, Native American, tribe, band, rancheria, and chief). Chapter 2 details historic and cultural changes related…

  2. Indian Education Curriculum Guidelines.

    ERIC Educational Resources Information Center

    Wise, Lu Celia, Ed.

    Designed in Oklahoma as a teaching aid for teachers in Indian education, this booklet is organized according to the subject areas of the curriculum. It provides a ready resource on Indian culture and should thus be of value to teachers who work with both Indian and non-Indian students. Guidelines for curriculum development in multicultural…

  3. Coast of the East Siberian Sea, Russia

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Sea ice is pulling away from the coastline of northeastern Siberia in the east Siberia Sea. This true-color Moderate Resolution Imaging Spectroradiometer (MODIS) image from May 26, 2002, also the thinning of ice in bays and coves, and the blue reflection of the water from beneath causes the ice to appear bright blue. Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  4. Modern Indian Psychology. Revised Edition.

    ERIC Educational Resources Information Center

    Bryde, John F.

    Written on the basis of senior Indian verbal relatings collected over a 23-year span, this revised edition on modern Indian psychology incorporates suggestions from Indian students and their teachers, Indian and non-Indian social studies experts, and other Indian people. The book contains 6 major divisions: (1) "Culture and Indian Values" relates…

  5. Tropical forcing of the recent rapid Arctic warming in northeastern Canada and Greenland.

    PubMed

    Ding, Qinghua; Wallace, John M; Battisti, David S; Steig, Eric J; Gallant, Ailie J E; Kim, Hyung-Jin; Geng, Lei

    2014-05-01

    Rapid Arctic warming and sea-ice reduction in the Arctic Ocean are widely attributed to anthropogenic climate change. The Arctic warming exceeds the global average warming because of feedbacks that include sea-ice reduction and other dynamical and radiative feedbacks. We find that the most prominent annual mean surface and tropospheric warming in the Arctic since 1979 has occurred in northeastern Canada and Greenland. In this region, much of the year-to-year temperature variability is associated with the leading mode of large-scale circulation variability in the North Atlantic, namely, the North Atlantic Oscillation. Here we show that the recent warming in this region is strongly associated with a negative trend in the North Atlantic Oscillation, which is a response to anomalous Rossby wave-train activity originating in the tropical Pacific. Atmospheric model experiments forced by prescribed tropical sea surface temperatures simulate the observed circulation changes and associated tropospheric and surface warming over northeastern Canada and Greenland. Experiments from the Coupled Model Intercomparison Project Phase 5 (ref. 16) models with prescribed anthropogenic forcing show no similar circulation changes related to the North Atlantic Oscillation or associated tropospheric warming. This suggests that a substantial portion of recent warming in the northeastern Canada and Greenland sector of the Arctic arises from unforced natural variability. PMID:24805345

  6. Superficial mineral resources of the Indian Ocean

    NASA Astrophysics Data System (ADS)

    Siddiquie, H. N.; Gujar, A. R.; Hashimi, N. H.; Valsangkar, A. B.

    The sea floor of the Indian Ocean and the continental margins bordering the ocean are covered by a wide variety of terrigenous, biogenous and anthigenic mineral deposits The humid tropical climate of some of the land areas bordering the Indian Ocean accelerates weathering of the source rocks. This coupled with the large river runoff and wave and current conditions favour the formation of a variety of placer deposits. The beach and offshore placer deposits of the Indian Ocean may be some of the largest in the world. The biogenous deposits in the Indian Ocean comprise the corals on shallow banks and on the continental shelves and the oozes in the deep sea. A study of these deposits is needed to acquire a better understanding of their formation, turnover, regeneration rates and sustainable yields. The anthigenic deposits in the Indian Ocean comprise the phosphorites and the polymetallic nodules. Occurrences of phosphorite deposits have been found both along continental margins (South Africa and Western India) and around seamounts (Eastern and Western Indian Ocean). The continental margins of South Africa, East Africa, Southern Arabia, Western India and the Andamans are marked by strong upwelling and provide non-depositional environments which are conducive to the formation of phosphorite. The polymetallic nodules in the Indian Ocean cover an area of 10-15. 10 6 km 2 and the resources are estimated to be about 1.5 .10 11 tonnes. A study of over 900 chemical analyses from 350 stations shows that the deposits in most of the basins are submarginal; in the Central Indian Ocean they are paramarginal (Ni + Cu + Co > 2.4% and concentrations > 5 kg.m -2). Most of the exploration for minerals even on the continental margins of the Indian Ocean has been carried out by the developed countries from outside the region and little work has been carried out by the countries bordering the Indian Ocean. The development of capabilities within the region for exploration of the mineral

  7. 226Ra in the western Indian Ocean

    NASA Astrophysics Data System (ADS)

    Chung, Y.

    1987-09-01

    226Ra profiles have been measured in the western Indian Ocean as part of the 1977-1978 Indian Ocean GEOSECS program. These profiles show a general increase in deep and bottom water Ra concentration from the Circumpolar region to the Arabian Sea. A deep Ra maximum which originates in the Arabian Sea and in the Somali basin at about 3000 m depth spreads southward into the Mascarene basin and remains discernible in the Madagascar and Crozet basins. In the western Indian Ocean, the cold Antarctic Bottom Water spreads northward under the possibly southward-flowing deep water, forming a clear benthic front along the Crozet basin across the Southwest Indian Ridge into the Madagascar and Mascarene basins. The Antarctic Bottom Water continues to spread farther north to the Somali basin through the Amirante Passage at 10°S as a western boundary current. The benthic front and other characteristic features in the western Indian Ocean are quite similar to those observed in the western Pacific where the benthic front as a distinctive feature was first described by Craig et al. [15]. Across the Mid-Indian Ridge toward the Ceylon abyssal plain near the triple junction, Ra profiles display a layered structure, reflecting the topographic effect of the mid-ocean ridge system on the mixing and circulation of the deep and bottom waters. Both Ra and Si show a deep maximum north of the Madagascar basin. Linear relationships between these two elements are observed in the deep and bottom water with slopes increasing northward. This suggests a preferential input of Ra over Si from the bottom sediments of the Arabian Sea and also from the flank sediments of the Somali basin.

  8. Roadside memorials in northeastern Thailand.

    PubMed

    Cohen, Erik

    In Thailand spirit houses are often established at places of fatal accidents, but these are generally anonymous. Personalized roadside memorials for accident victims are rare. This article analyses three roadside memorials, located on main roads in northeastern Thailand, in a comparative framework. Like in the contemporary West, such memorials commemorate a suddenly and violently killed person, but manifest a dynamics very different from that of Western roadside memorials: rather than private and temporary, these are permanent shrines, in which the spirit of the deceased is worshipped and supplicated by members of the public. The spirits and their shrines tend to become incorporated into the popular Thai magico-religious complex. While the literature offers a binary distinction between formal public monuments and informal, private and temporary (roadside) memorials, it is suggested that the informal, but public and permanent memorial shrines in Thailand exemplify a third type of edifices to commemorate the deceased in road accidents. PMID:23785985

  9. Improvising on an Indian Flute.

    ERIC Educational Resources Information Center

    Giles, Martha Mead

    1984-01-01

    The Indian flute can be used by teachers to supplement classroom study of Indian culture. Indians used it as a personal instrument. Describes how an Indian flute can be made, and suggests improvising bird calls and melodies on it. (CS)

  10. "Indian Education in the Bureau of Indian Affairs."

    ERIC Educational Resources Information Center

    Hawkins, James E.

    The role of the Bureau of Indian Affairs (BIA) in American Indian education is discussed in this speech. At the present time, this role is limited to federally recognized Indians living on reservations or Indian trust land; for other Indian students, the BIA's role is that of an advocate, helping Indian people get what they want and need in regard…

  11. The Indian Languages

    ERIC Educational Resources Information Center

    Strong, Augusta

    1969-01-01

    Appraisal of Boas'"Introduction to Handbook of American Indian Languages (1911), and Powell's "Indian Linguistic Famlies of America North of Mexico (1891), as reissued by University of Nebraska, Lincoln. (AF)

  12. 78 FR 16685 - Indian Health Professions Preparatory, Indian Health Professions Pre-graduate, and Indian Health...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-18

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HEALTH AND HUMAN SERVICES Indian Health Service Indian Health Professions Preparatory, Indian Health Professions Pre-graduate, and Indian Health Professions Scholarship Programs Announcement Type: Initial. ]...

  13. 75 FR 1384 - Indian Health Professions Preparatory, Indian Health Professions Pregraduate and Indian Health...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-11

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HEALTH AND HUMAN SERVICES Indian Health Service Indian Health Professions Preparatory, Indian Health Professions Pregraduate and Indian Health Professions Scholarship Programs Announcement Type: Initial. CFDA Numbers:...

  14. Indian Education Project: An Abridgment.

    ERIC Educational Resources Information Center

    Stevenson, Sharon

    Synthesizing two priority proposals identified by the Indian Education Project of Michigan, this report outlines a proposal for establishing an Indian Education Center (staffed by American Indians and advised by a University Advisory Committee made up of Indian parents and the Indian community) to meet the needs of Indian students and…

  15. Isotopic characteristics of Indian precipitation

    NASA Astrophysics Data System (ADS)

    Kumar, Bhishm; Rai, S. P.; Kumar, U. Saravana; Verma, S. K.; Garg, Pankaj; Kumar, S. V. Vijaya; Jaiswal, Rahul; Purendra, B. K.; Kumar, S. R.; Pande, N. G.

    2010-12-01

    Hydrogen (2H/1H) and oxygen (18O/16O) isotopic ratios were measured in precipitation (900 samples) collected from several locations in India during the period 2003-2006 (12 locations in 2003 and 18 locations in 2004-2006). The amount of rainfall along with air temperature and humidity were also measured. The meteoric water line developed for India using isotopic data of precipitation samples, namely, δ2H = 7.93(±0.06) × δ18O + 9.94(±0.51) (n = 272, r2 = 0.98), differs slightly from the global meteoric water line. Regional meteoric water lines were developed for several Indian regions (i.e., northern and southern regions of India, western Himalayas) and found to be different from each other (southern Indian meteoric water line, slope is 7.82, intercept or D excess is 10.23; northern Indian meteoric water line, slope is 8.15, intercept is 9.55) which is attributed to differences in their geographic and meteorological conditions and their associated atmospheric processes (i.e., ambient temperature, humidity, organ, and source of vapor masses). The local meteoric water lines developed for a number of locations show wide variations in the slope and intercept. These variations are due to different vapor sources such as the northeast (NE) monsoon that originates in the Bay of Bengal; the southwest monsoon (SW) that originates in the Arabian Sea; a mixture of NE and SW monsoons; retreat of NE and SW monsoons and western disturbances that originate in the Mediterranean Sea. The altitude effect in the isotopic composition of precipitation estimated for western Himalayan region also varies from month to month.

  16. Anatomy of Indian heatwaves.

    PubMed

    Ratnam, J V; Behera, Swadhin K; Ratna, Satyaban B; Rajeevan, M; Yamagata, Toshio

    2016-01-01

    India suffers from major heatwaves during March-June. The rising trend of number of intense heatwaves in recent decades has been vaguely attributed to global warming. Since the heat waves have a serious effect on human mortality, root causes of these heatwaves need to be clarified. Based on the observed patterns and statistical analyses of the maximum temperature variability, we identified two types of heatwaves. The first-type of heatwave over the north-central India is found to be associated with blocking over the North Atlantic. The blocking over North Atlantic results in a cyclonic anomaly west of North Africa at upper levels. The stretching of vorticity generates a Rossby wave source of anomalous Rossby waves near the entrance of the African Jet. The resulting quasi-stationary Rossby wave-train along the Jet has a positive phase over Indian subcontinent causing anomalous sinking motion and thereby heatwave conditions over India. On the other hand, the second-type of heatwave over the coastal eastern India is found to be due to the anomalous Matsuno-Gill response to the anomalous cooling in the Pacific. The Matsuno-Gill response is such that it generates northwesterly anomalies over the landmass reducing the land-sea breeze, resulting in heatwaves. PMID:27079921

  17. Anatomy of Indian heatwaves

    NASA Astrophysics Data System (ADS)

    Ratnam, J. V.; Behera, Swadhin K.; Ratna, Satyaban B.; Rajeevan, M.; Yamagata, Toshio

    2016-04-01

    India suffers from major heatwaves during March-June. The rising trend of number of intense heatwaves in recent decades has been vaguely attributed to global warming. Since the heat waves have a serious effect on human mortality, root causes of these heatwaves need to be clarified. Based on the observed patterns and statistical analyses of the maximum temperature variability, we identified two types of heatwaves. The first-type of heatwave over the north-central India is found to be associated with blocking over the North Atlantic. The blocking over North Atlantic results in a cyclonic anomaly west of North Africa at upper levels. The stretching of vorticity generates a Rossby wave source of anomalous Rossby waves near the entrance of the African Jet. The resulting quasi-stationary Rossby wave-train along the Jet has a positive phase over Indian subcontinent causing anomalous sinking motion and thereby heatwave conditions over India. On the other hand, the second-type of heatwave over the coastal eastern India is found to be due to the anomalous Matsuno-Gill response to the anomalous cooling in the Pacific. The Matsuno-Gill response is such that it generates northwesterly anomalies over the landmass reducing the land-sea breeze, resulting in heatwaves.

  18. Anatomy of Indian heatwaves

    PubMed Central

    Ratnam, J. V.; Behera, Swadhin K.; Ratna, Satyaban B.; Rajeevan, M.; Yamagata, Toshio

    2016-01-01

    India suffers from major heatwaves during March-June. The rising trend of number of intense heatwaves in recent decades has been vaguely attributed to global warming. Since the heat waves have a serious effect on human mortality, root causes of these heatwaves need to be clarified. Based on the observed patterns and statistical analyses of the maximum temperature variability, we identified two types of heatwaves. The first-type of heatwave over the north-central India is found to be associated with blocking over the North Atlantic. The blocking over North Atlantic results in a cyclonic anomaly west of North Africa at upper levels. The stretching of vorticity generates a Rossby wave source of anomalous Rossby waves near the entrance of the African Jet. The resulting quasi-stationary Rossby wave-train along the Jet has a positive phase over Indian subcontinent causing anomalous sinking motion and thereby heatwave conditions over India. On the other hand, the second-type of heatwave over the coastal eastern India is found to be due to the anomalous Matsuno-Gill response to the anomalous cooling in the Pacific. The Matsuno-Gill response is such that it generates northwesterly anomalies over the landmass reducing the land-sea breeze, resulting in heatwaves. PMID:27079921

  19. Indians of North Carolina.

    ERIC Educational Resources Information Center

    Bureau of Indian Affairs (Dept. of Interior), Washington, DC.

    A brief historical review of the Cherokee Indians from the mid-sixteenth century to modern day depicts an industrious tribe adversely affected by the settlement movement only to make exceptional economic advancements with the aid of the Bureau of Indian Affairs. Civic pride and self-leadership among the Cherokee Indians in North Carolina has…

  20. Canada's Indians. Revised Edition.

    ERIC Educational Resources Information Center

    Wilson, James

    Over a half million people in Canada today are identifiably of Native ancestry, legally categorized as Inuit (Eskimos), status Indians, or nonstatus Indians. Status Indians comprise 573 bands with total membership of about 300,000 people, most of whom live on 2,242 reserves. They are the direct responsibility of the federal government and have…

  1. National Indian Education Study

    ERIC Educational Resources Information Center

    Harvey, Karen Kay

    2006-01-01

    This report includes information from the National Indian Education Study of American Indian/Alaska Native students in grades 4 and 8 on the 2005 National Assessment of Education Progress (NAEP) in reading and mathematics. The national sample includes both public and private schools (i.e. Bureau of Indian Affairs, Department of Defense Education…

  2. Indian Law Enforcement History.

    ERIC Educational Resources Information Center

    Etheridge, David

    Written as a tribute to American Indian law enforcement officers and the Indian Criminal Justice System, this monographh details the history of the legislative, judicial, financial, and cultural problems associated with the development of Indian law enforcement. Citing numerous court cases, pieces of legislation, and individual and organizational…

  3. Urban American Indian Aging.

    ERIC Educational Resources Information Center

    Kramer, Josea

    This document begins by dispelling several misperceptions about American Indians that are especially pernicious to older American Indians living in cities, and then goes on to discuss what is known about urban American Indian elders and the implications for planning and service delivery for Area Agencies on Aging and contractor agencies. It notes…

  4. Minnesota Indian Resources Directory.

    ERIC Educational Resources Information Center

    Mayer, Catherine M., Comp.; And Others

    The second edition of the directory of organizations operating in the Indian communities throughout the State of Minnesota is an attempt to compile all current information on resources available to the Minnesota Indian. The introductory section discusses the problems faced by the Indian American in urban sectors with reference to their life styles…

  5. 77 FR 21568 - Indian Health Professions Preparatory, Indian Health Professions Pregraduate and Indian Health...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-10

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HEALTH AND HUMAN SERVICES Indian Health Service Indian Health Professions Preparatory, Indian Health Professions Pregraduate and Indian Health Professions Scholarship Programs Overview Information: Indian Health Professions Preparatory, Indian Health...

  6. A Little Boy Eats Too Much. Indian Culture Series.

    ERIC Educational Resources Information Center

    Holthaus, Mary L.

    Part of the Indian Culture Series of the Montana Council for Indian Education, the book is a simple story of a young Alaskan boy who makes oil lamps and his grandmother who sews with a needle. The little boy goes to hunt by the sea because they are hungry. He catches and eats a tomcod, two seals, and a whale, then returns to the igloo having eaten…

  7. Vulnerability of Northeastern U.S. Salt Marshes to Climatic and Anthropogenic Stressors

    NASA Astrophysics Data System (ADS)

    Watson, E. B.; Oczkowski, A. J.; Hanson, A.; Davey, E. W.; Crosby, S. C.; Johnson, R. L.

    2014-12-01

    In the Northeastern U.S., salt marsh area is in decline. Habitat change analysis has revealed fragmentation, displacement of high marsh by low marsh species, and ecological drowning, while development of adjacent uplands limits upslope migration. Using inundation experiments, field surveys, and LiDAR datasets, we developed an elevation-productivity relationship for Spartina alterniflora specific to the U.S. Northeast states of New York, Connecticut, Rhode Island, southern Massachusetts and located current salt marsh orthometric heights on this curve. We determined that 89% of salt marshes in these Northeastern states are located at elevations where growth is limited by inundation, suggesting links between current salt marsh loss patterns and sea level rise. By manipulating water column nutrients, precipitation, and elevation, we further found that altered precipitation receipt was associated with significant reductions in biomass, and that nutrient enrichment adversely impacts organic matter accumulation and peat formation. These results provide evidence that Northeastern U.S. marshes are vulnerable to the effects of accelerated sea level rise, and that neither precipitation changes, nor cultural eutrophication, will contribute positively to long-term salt marsh survival.

  8. An oceanic teleconnection between the equatorial and southern Indian Ocean

    NASA Astrophysics Data System (ADS)

    Schouten, M. W.; de Ruijter, W. P. M.; van Leeuwen, P. J.; Dijkstra, H. A.

    2002-08-01

    Sequences of Kelvin and Rossby waves are found to rapidly carry sea surface height anomalies across the Indian Ocean, and have an impact on Indian to Atlantic interocean exchange. Satellite altimeter data reveal an oceanic teleconnection between equatorial winds and variability of the interocean exchange. Four times per year, we observe an equatorial Kelvin wave to hit Indonesia, forced by monsoon variability. The signal then propagates southward along the Indonesian coast and triggers Rossby waves that propagate westward across the subtropical Indian Ocean. On reaching the Madagascar and Mozambique Channel regions, large rings form at the same four per year frequency. These drift towards the Agulhas retroflection where they control the shedding of Agulhas rings. Disturbances of this pin-ball-like propagating signal can be traced from Indian Ocean Dipole/El Niño events in 1994 and 1997/1998, to decreases of Indian-Atlantic ocean exchange by Agulhas rings over two years later.

  9. Impact of water mass mixing and dust deposition on Nd concentration and εNd of the Arabian Sea water column

    NASA Astrophysics Data System (ADS)

    Goswami, Vineet; Singh, Sunil K.; Bhushan, Ravi

    2014-11-01

    The concentration and isotopic composition (εNd) of dissolved Nd have been measured in the sub-oxic/denitrifying water column of the eastern Arabian Sea to explore the impact of water mass mixing and release from particles. Dissolved Nd in the north-eastern Arabian Sea is more radiogenic (εNd: -7 to -10) compared to its south-eastern part (εNd: -11 to -15) suggesting contribution of Nd from the Bay of Bengal (BoB). The vertical profile of Nd typically show higher values in surface waters (15.8-27.8 pmol/kg), followed by minima (12-18 pmol/kg) in the subsurface waters (200-300 m) and a gradual increase with depth thereafter. The Nd concentration does not seem to show any changes in the sub-oxic layers suggesting no impact of the sub-oxic/denitrifying conditions in this oceanic region on the biogeochemistry of Nd. The enrichment of Nd in surface waters can be explained either by supply from high Nd low salinity waters from the BoB to the Arabian Sea via the East India Coastal Current (EICC) or, alternatively the Nd surface excess can be result of release from aeolian dust depositing over the sea surface. Inverse modeling computations suggest that in addition to Nd contributed from water mass mixing, some additional excess Nd (Ndxs) is required to balance the Nd inventory in the water column. There is significant Ndxs in the surface waters of the north-eastern Arabian Sea with εNd ∼ -6, similar to that of dust depositing over the Arabian Sea. The fractional solubility of Nd released from the aeolian dust was estimated to be varying from ∼3% to 17% (for excess Nd inventory per unit area (Ndxs∗) of 20 μg m-2 with τNd ranging from 1 to 3 years). This study highlights the significance of aeolian dust deposition in controlling the abundance and distribution of Nd in the Arabian Sea, the western arm of the northern Indian Ocean, lying in the proximity to the arid landmass and characterized by high lithogenic aeolian dust deposition.

  10. Gene flow and population subdivision in a pantropical plant with sea-drifted seeds Hibiscus tiliaceus and its allied species: evidence from microsatellite analyses.

    PubMed

    Takayama, Koji; Tateishi, Yoichi; Murata, Jin; Kajita, Tadashi

    2008-06-01

    The genetic differentiation and structure of Hibiscus tiliaceus, a pantropical plant with sea-drifted seeds, and four allied species were studied using six microsatellite markers. A low level of genetic differentiation was observed among H. tiliaceus populations in the Pacific and Indian Ocean regions, similar to the results of a previous chloroplast DNA (cpDNA) study. Frequent gene flow by long-distance seed dispersal is responsible for species integration of H. tiliaceus in the wide distribution range. On the other hand, highly differentiated populations of H. tiliaceus were detected in West Africa, as well as of Hibiscus pernambucensis in southern Brazil. In the former populations, the African continent may be a geographical barrier that prevents gene flow by sea-drifted seeds. In the latter populations, although there are no known land barriers, the bifurcating South Equatorial Current at the north-eastern horn of Brazil can be a potential barrier to gene flow and may promote the genetic differentiation of these populations. Our results also suggest clear species segregation between H. tiliaceus and H. pernambucensis, which confirms the introgression scenario between these two species that was suggested by a previous cpDNA study. Our results also provide good evidence for recent transatlantic long-distance seed dispersal by sea current. Despite the distinct geographical structure observed in the cpDNA haplotypes, a low level of genetic differentiation was found between Pacific and Atlantic populations of H. pernambucensis, which could be caused by transisthmian gene flow. PMID:18482261

  11. Variability of the southwest Indian Ocean.

    PubMed

    de Ruijter, Wilhelmus P M; Ridderinkhof, Herman; Schouten, Mathijs W

    2005-01-15

    The variability in the southwest Indian Ocean is connected to the basin-scale and global-scale ocean circulation. Two bands of enhanced variability stretch across the Southern Indian Ocean east of Madagascar around 12 degrees S and 25 degrees S, respectively. They mark the preferred routes along which anomalies, generated by varying forcing over the central basin, near the eastern boundary or in the equatorial region, propagate westward as baroclinic Rossby waves. Sea-surface height anomalies pass along the northern tip of Madagascar and are observed by satellite altimetry to propagate into the central Mozambique Channel. There, eddies are subsequently formed that propagate southward into the Agulhas retroflection region. The anomalies along the southern band trigger the formation of large dipolar vortex pairs in the separation region of the East Madagascar Current at the southern tip of the island. South of Africa these eddies and dipoles trigger the shedding of Agulhas Rings that feed the Atlantic meridional overturning circulation with warm, salty, Indian Ocean water. Interannual variability of the forcing over the Indian Ocean, such as that associated with the Indian Ocean Dipole/El Nino climate modes, propagates along these pathways and leads to associated modulations of the eddy transports into the South Atlantic. PMID:15598623

  12. First Data on Lake Level Changes in Northeastern Siberia during the Postglacial Time

    SciTech Connect

    Shilo, N A; Anderson, P M; Brown, T A; Lozhkin, A V; Pakhomov, A Y; Solomatkina, T B

    2005-05-18

    Moraines of the Tyellakh Group [1] (QIII{sub 2-4}) preserved in river valleys of the northeastern Kolyma River basin indicate development of cirque-valley glaciers originating in the Kilgan Mountains located at the northeastern periphery of the Kolyma Ridge that separates drainage basins of the Sea of Okhotsk and Kolyma River. Moraines host lakes with a length of up to 1-5 km and a relatively small width depending on the valley bottom dimension. The study of lacustrine sediments, their bed-by-bed palynological analysis, and radiocarbon dating provided the first information on lake levels during the final glacial stage of the Late Pleistocene, as well as the Pleistocene-Holocene boundary and Holocene, for the upper reaches of the Kolyma River.

  13. Correlation of the Jurassic through Oligocene Stratigraphic Units of Trinidad and Northeastern Venezuela

    SciTech Connect

    Algar, S.; Erikson, J.P.

    1995-04-01

    The Jurassic through Oligocene stratigraphies of Trinidad and the Serrenia del Interior of eastern Venezuela exhibit many similarities because of their proximity on the passive continental margins of northeastern South America. A slightly later subsidence in eastern Venezuela, and the generally deeper-water sedimentation in Trinidad, is interpreted to be the result of a serration of the original rift margin, producing an eastern Venezuela promontory and Trinidadian re-entrant. We interpret these serrations to be the result of oblique (NW-SE) spreading of North and South America during Middle and late Jurassic time. The stratigraphies of northeastern Venezuela and Trinidad contrast in the Hauterivan-Albian interval, with dynamic shallow shelf environments prevailing in the Serrenia del Interior and deeper marine submarine-fan deposition in Trinidad. Both areas develop middle to Upper Cretaceous source rocks during a time of eustatic sea level high and widespread oceanic anoxia. 15 refs., 4 fig.

  14. Late Ordovician-Early Silurian chitinozoans from north-eastern and western Illinois, USA

    USGS Publications Warehouse

    Butcher, A.; Mikulic, Donald G.; Kluessendorf, Joanne

    2010-01-01

    Samples of uppermost Ordovician and Silurian strata from two cores from north-eastern and western Illinois were processed for chitinozoans. Due to apparent sea-floor oxidation or palaeoenvironmental constraints, very few samples yielded specimens, but those that did allow tentative correlation with established biostratigraphical zonations for the Chitinozoa. Samples from the Wilhelmi Formation of core DH76-21 in north-eastern Illinois yielded Spinachitina fragilis, a typically earliest Silurian taxon. A sample from the Maquoketa Group strata of core Principia #4, western Illinois, yielded a monospecific assemblage of Conochitina elegans, which is suggestive of a late Ordovician age. Higher in this core, a sample from the upper strata of the Bowling Green Dolomite yielded an assemblage indicating a late Rhuddanian to Aeronian age, including Angochitina hansonica, previously only described from strata in Nevada, and one new species, Fungochitina illinoisensis. ?? 2009 Elsevier B.V. All rights reserved.

  15. Indianization of psychiatry utilizing Indian mental concepts.

    PubMed

    Avasthi, Ajit; Kate, Natasha; Grover, Sandeep

    2013-01-01

    Most of the psychiatry practice in India is guided by the western concepts of mental health and illness, which have largely ignored the role of religion, family, eastern philosophy, and medicine in understanding and managing the psychiatric disorders. India comprises of diverse cultures, languages, ethnicities, and religious affiliations. However, besides these diversities, there are certain commonalities, which include Hinduism as a religion which is spread across the country, the traditional family system, ancient Indian system of medicine and emphasis on use of traditional methods like Yoga and Meditation for controlling mind. This article discusses as to how mind and mental health are understood from the point of view of Hinduism, Indian traditions and Indian systems of medicine. Further, the article focuses on as to how these Indian concepts can be incorporated in the practice of contemporary psychiatry. PMID:23858244

  16. Indianization of psychiatry utilizing Indian mental concepts

    PubMed Central

    Avasthi, Ajit; Kate, Natasha; Grover, Sandeep

    2013-01-01

    Most of the psychiatry practice in India is guided by the western concepts of mental health and illness, which have largely ignored the role of religion, family, eastern philosophy, and medicine in understanding and managing the psychiatric disorders. India comprises of diverse cultures, languages, ethnicities, and religious affiliations. However, besides these diversities, there are certain commonalities, which include Hinduism as a religion which is spread across the country, the traditional family system, ancient Indian system of medicine and emphasis on use of traditional methods like Yoga and Meditation for controlling mind. This article discusses as to how mind and mental health are understood from the point of view of Hinduism, Indian traditions and Indian systems of medicine. Further, the article focuses on as to how these Indian concepts can be incorporated in the practice of contemporary psychiatry. PMID:23858244

  17. The Indian Child Welfare Act.

    ERIC Educational Resources Information Center

    Steward, Katy Jo

    The Indian Child Welfare Act of 1978 (I.C.W.A.) is federal legislation which preempts state law whenever Indian children may be removed from their families. The I.C.W.A. permits Indian tribal courts to decide the future of Indian children, establishes minimum federal standards for removal of Indian children from their families, requires that…

  18. 75 FR 38834 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-06

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of... INFORMATION CONTACT: Paula L. Hart, Director, Office of Indian Gaming, Office of the Deputy Assistant...: Under Section 11 of the Indian Gaming Regulatory Act of 1988 (IGRA), Public Law 100-497, 25 U.S.C....

  19. 76 FR 42722 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-19

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of... FURTHER INFORMATION CONTACT: Paula L. Hart, Director, Office of Indian Gaming, Office of the Assistant... of the Indian Gaming Regulatory Act of 1988 (IGRA), Public Law 100-497, 25 U.S.C. 2710, the...

  20. 76 FR 165 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-03

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of... the Menominee Indian Tribe of Wisconsin (``Tribe'') and the State of Wisconsin Gaming Compact of 1992... CONTACT: Paula L. Hart, Director, Office of Indian Gaming, Office of the Deputy Assistant...

  1. A new species of Afropinnotheres Manning, 1993 (Crustacea, Brachyura, Pinnotheridae) from southwestern India, the first record of the genus from the Indian Ocean, with a review of the Pinnotheridae of India and adjacent seas.

    PubMed

    Ng, Peter K L; Kumar, Appukuttannair Biju

    2015-01-01

    A new species of pinnotherid crab of the genus Afropinnotheres Manning, 1993, is described from the brown mussel, Perna perna (Linnaeus, 1758), in southwestern India. This is the first record of the genus from the western Indian Ocean, the other four species been recorded from the eastern Atlantic. The new species can be distinguished from all congeners in  possessing a more rounded male carapace, form of the chela, relatively longer ambulatory legs which have no natatory setae, presence of dense pubescence on the male ambulatory legs, and the shape of the male and female telsons. The Indian Pinnotheridae is also reviewed and the taxonomy of the species reappraised. The taxonomy of Pinnaxodes Heller, 1865, and Holothuriophilus Nauck, 1880, is also discussed, in the context of their similarity to Afropinnotheres. PMID:25947734

  2. Crustal structure of northeastern California

    NASA Astrophysics Data System (ADS)

    Zucca, John J.; Fuis, Gary S.; Milkereit, Bernd; Mooney, Walter D.; Catchings, Rufus D.

    1986-06-01

    In 1981, the U.S. Geological Survey conducted a seismic refraction survey of northeastern California designed to characterize the structure in four geologic provinces: the Klamath Mountains, Cascade Range, Modoc Plateau, and Basin and Range provinces. The survey consisted of north-south lines in the Klamath Mountains and Modoc Plateau provinces, northwest-southeast lines centered on Mount Shasta and Medicine Lake volcano, and an east-west line linking all the profiles. All lines except the east-west line ranged in length from 125 to 140 km, contained three shot points, and were recorded by 100 instruments. The east-west line was 260 km long, contained six shot points, and was recorded by 200 instruments. The Klamath and Modoc lines yielded the simplest models. The Klamath model is finely layered from the surface to at least 14-km depth, consisting of a series of high-velocity layers (6.1-6.7 km/s), ranging in thickness from 1 to 4 km, with alternating positive and negative velocity gradients. A layer with an unreversed velocity of 7.0 km/s extends from 14 km downward to an unknown depth. The Modoc model, in contrast, is thickly layered and has lower velocity at all depths down to 25 km. The uppermost layer, 4.5 km thick, consists of low-velocity material (2-4.5 km/s). Velocity beneath this layer is much higher (6.2 km/s) and increases slowly with depth. A small velocity step (to 6.4 km/s) is seen at 11 km, and a larger step (to 7.0 km/s) is seen at 25 km depth. Moho is probably 38-45 km deep under the Modoc Plateau, but its depth is unknown under the Klamath Mountains. Models for the Shasta and Medicine Lake lines show special features including low velocity (less than 3.5 km/s) in the edifice of Mount Shasta but high velocity (5.6 km/s) at shallow depth (1-2 km) under the summit of Medicine Lake volcano. The model for the east-west line consists of a western part similar to the Klamath model, an eastern part similar to the Modoc model, and laterally changing

  3. Pleistocene Indian Monsoon Rainfall Variability

    NASA Astrophysics Data System (ADS)

    Yirgaw, D. G.; Hathorne, E. C.; Giosan, L.; Collett, T. S.; Sijingeo, A. V.; Nath, B. N.; Frank, M.

    2014-12-01

    The past variability of the Indian Monsoon is mostly known from records of wind strength over the Arabian Sea. Here we investigate proxies for fresh water input and runoff in a region of strong monsoon precipitation that is a major moisture source for the east Asian Monsoon. A sediment core obtained by the IODP vessel JOIDES Resolution and a gravity core from the Alcock Seamount complex in the Andaman Sea are used to examine the past monsoon variability on the Indian sub-continent and directly over the ocean. The current dataset covers the last glacial and deglacial but will eventually provide a Pleistocene record. We utilise the ecological habitats of G. sacculifer and N. dutertrei to investigate the freshwater-induced stratification with paired Mg/Ca and δ18O analyses to estimate seawater δ18O (δ18Osw). During the last 60 kyrs, Ba/Ca ratios and δ18Osw values generally agree well between the two cores and suggest the weakest surface runoff and monsoon during the LGM and strongest monsoon during the Holocene. The difference in δ18O between the species, interpreted as a proxy for upper ocean stratification, implies stratification developed around 37 ka and remained relatively constant during the LGM, deglacial and Holocene. To investigate monsoon variability for intervals in the past, single shell Mg/Ca and δ18O analyses have been conducted. Mg/Ca ratios from individual shells of N. dutertrei suggest relatively small changes in temperature. However, individual N. dutertrei δ18O differ greatly between the mid-Holocene and samples from the LGM and a nearby core top. The mid-Holocene individuals have a greater range and large skew towards negative values indicating greater fresh water influence.

  4. CHARCOAL-PRODUCING INDUSTRIES IN NORTHEASTERN BRAZIL

    EPA Science Inventory

    Charcoal workers in northeastern Brazil: Occupational risks and effects of exposure to wood smoke
    ABSTRACT
    Brazil has the largest production of charcoal in the world, which is used mostly in the iron and steel industries. In most of the production sites, the process is ba...

  5. Superintendent Communication Patterns in Northeastern Indiana

    ERIC Educational Resources Information Center

    Clendening, David Earl

    2009-01-01

    The purpose of the qualitative study was to examine the communication patterns of superintendents in Northeastern Indiana. The demand for accountability, transparency, and student achievement calls for today's superintendent to increase communication strategies and support the needs of the varied stakeholders. Today's public school leaders are…

  6. Chemical Dependency Regional Needs Assessment: Northeastern Minnesota.

    ERIC Educational Resources Information Center

    Stone, Marylee

    The Minnesota Model of Chemical Dependency Treatment, which evolved from a combination of the grassroots Alcoholics Anonymous movement and the State Mental Health Services in the 1960s has made Minnesota an international leader in chemical dependency treatment efforts. Northeastern Minnesota has shared this reputation with the state. In spite of…

  7. The American Indian: A Natural Philosopher

    ERIC Educational Resources Information Center

    Bunge, Robert P.

    1978-01-01

    Describes American Indian philosophy, Indian attitudes on man's place in the cosmos, Indian socio-political practice, Indian moral values and community philosophy, and the differences between "white" and Indian culture. (RK)

  8. Protecting American Indian Children.

    ERIC Educational Resources Information Center

    Fischler, Ronald S.; And Others

    1980-01-01

    The passage of the Indian Child Welfare Act has caused concern and misunderstanding among social workers. The Act is seen as a victory for tribal sovereignty but must be viewed within the context of American Indian culture and child rearing practices. (Author/JAC)

  9. Contemporary American Indian Studies

    ERIC Educational Resources Information Center

    Larson, Sidner

    2009-01-01

    In his keynote address to the Fifth Annual American Indian Studies Consortium in 2005 David Wilkins began by commenting on earlier attempts to formally organize such a gathering in ways that might help establish and accredit Indian studies programs. He said he had the sense that the thrust of earlier meetings "was really an opportunity for Native…

  10. The Tarascan Indian House.

    ERIC Educational Resources Information Center

    Quinn, Joyce

    1989-01-01

    This lesson plan introduces K-grade three students to Mexican Indian architecture. Students will become familiar with the cultural context of the Indian treasure house; discuss the use of wood as the sole building material; compare the treasure house with present day structures; and create miniature treasure houses using wood materials. (GEA)

  11. America's Indian Statues.

    ERIC Educational Resources Information Center

    Gridley, Marion E., Comp.

    A comprehensive compilation of facts and photographs of statues honoring or memorializing the American Indians is presented in this paperback. The vignettes accompanying the photographs are the result of extensive research. Examples of the American Indian statues include "The Signal of Peace,""The Protest,"" The Medicine Man,""Appeal to the Great…

  12. The (East) Indian Woman.

    ERIC Educational Resources Information Center

    Naidoo, Josephine

    The focus of this paper is on the social, cultural, and psychological problems women of East Indian origin share with other immigrant women in Canada. Also examined are problems that are unique to the East Indian woman and the ways in which she deals with the challenges, conflicting cultural values, and expectations that confront her. The…

  13. Pima Indian Legends.

    ERIC Educational Resources Information Center

    Shaw, Anna Moore

    The stated purpose of this book is to preserve in writing some of the Pima Indian legends that had been verbally passed from generation to generation in the past. This collection of 23 legends, which were originally used to instruct the young people of the tribe, presents in story form various aspects of American Indian life--including…

  14. The Omaha Indians

    ERIC Educational Resources Information Center

    Springer, W. F.

    1976-01-01

    Briefly recounting the history of the Omaha American Indians, this article makes a plea for relocation of the Bureau of Indian Affairs local Agency in Macy near the Omaha reservation, suggesting that the Returned Students movement is a response to this need for the Agency's relocation. (JC)

  15. Indians of Arizona.

    ERIC Educational Resources Information Center

    Bureau of Indian Affairs (Dept. of Interior), Washington, DC.

    Briefly describing each tribe within Arizona's four major American Indian groups, this handbook presents information relative to the cultural background and socioeconomic development of the following tribes: (1) Athapascan Tribes (Navajos and Apaches); (2) Pueblo Indians (Hopis); (3) Desert Rancheria Tribes (Pimas, Yumas, Papagos, Maricopas,…

  16. Indian Inuit Pottery '73

    ERIC Educational Resources Information Center

    Tawow, 1974

    1974-01-01

    A unique exhibit of Canadian Native Ceramics which began touring various art galleries in September 1973 is described both verbally and photographically. The Indian Inuit Pottery '73 display, part of the 1973 International Ceramics Exhibition, includes 110 samples of craftsmanship from Indian and Inuit artists across Canada. (KM)

  17. Indians in Careers.

    ERIC Educational Resources Information Center

    Hollow, Kitty, Ed.; Heuving, Jeanne, Ed.

    Every student in high school is faced with the question of what to do after graduation. American Indian students, whether on or off reservations, need ideas as to what is available to them. This compilation of interviews with 10 individuals who are maintaining their "Indian identity" and making contributions in the working world provides role…

  18. Coastal Change Along the Shore of Northeastern South Carolina: The South Carolina Coastal Erosion Study

    USGS Publications Warehouse

    Barnhardt, W. A., (Edited By)

    2009-01-01

    The U.S. Geological Survey, in cooperation with the South Carolina Sea Grant Consortium, conducted a 7-year, multi-disciplinary study of coastal erosion in northeastern South Carolina. The main objective was to understand the geologic and oceanographic processes that control sediment movement along the region's shoreline and thereby improve projections of coastal change. The study used high-resolution remote sensing and sampling techniques to define the geologic framework and assess historic shoreline change. Based on these findings, oceanographic-process studies and numerical modeling were carried out to determine the rates and directions of sediment transport along South Carolina's Grand Strand.

  19. Role of the Indian and Pacific oceans in the Indian summer monsoon variability

    NASA Astrophysics Data System (ADS)

    Achuthavarier, Deepthi

    The role of the Indian and Pacific sea surface temperature (SST) variability in the intraseasonal and interannual variability of the Indian summer monsoon rainfall is examined by performing a set of regionally coupled experiments with the Climate Forecast System (CFS), the latest and operational coupled general circulation model (CGCM) developed at the National Centers for Environmental Prediction (NCEP). The intraseasonal and interannual variability are studied by isolating oscillatory and persistent signals, respectively, from the unfiltered daily rainfall anomalies using multi-channel singular spectrum analysis (MSSA). This technique identifies nonlinear oscillations, its variance and period without preconditioning the data with a filter and also helps to separate the intraseasonal and low frequency climate signals from the daily variability. It is found that, although the model has large amount of daily variance in rainfall, the combined variance of coherently propagating intraseasonal oscillations is only about 7% while the corresponding number in the observations is 11%. The model has three intraseasonal oscillations with periods around 106, 57 and 30 days. The 106-day mode has a characteristic large-scale pattern extending from the Arabian Sea to the West Pacific with northward and eastward propagations. These features are similar to the northeastward propagating 45-day mode found in the observations except for the longer period. The 57-day mode is more dominant in the region, 60°E-100°E and is strictly northward-propagating. The 30-day mode appears to be equivalent to the northwestward propagating oscillation in the observations. The dominant low frequency persistent signal in the region is due to the El Nino-Southern Oscillation (ENSO). The ENSO-related rainfall anomalies, however fail to penetrate into the Extended Indian Monsoon Rainfall (EIMR) region, and therefore, the ENSO-monsoon relationship in the model is weak. Regionally coupled simulations of

  20. Investigation of plateau basin crustal structures and thickening mechanisms in the northeastern margin of the Tibetan plateau

    NASA Astrophysics Data System (ADS)

    Jia, Shixu; Xu, Zhaofan; Liu, Zhi; Zhang, Jianshi; Liu, Baofeng; Lin, Jiyan; Guo, Wenbin

    2012-12-01

    This paper uses deep seismic sounding (DSS) data to contrast and analyze the crustal structures of three plateau basins (Songpan-Garze, Qaidam, Longzhong) in the northeastern margin of the Qinghai-Xizang (Tibetan) plateau, as well as two stable cratonic basins (Ordos, Sichuan) in its peripheral areas. Plateau basin crustal structures, lithological variations and crustal thickening mechanisms were investigated. The results show that, compared to the peripheral stable cratonic basins, the crystalline crusts of plateau basins in the northeastern margin are up to 10-15 km thicker, and the relative medium velocity difference is about 5% less. The medium velocity change in crustal layers of plateau basin indicates that the upper crust undergoes brittle deformation, whereas the lower crust deforms plastically with low velocity. The middle crust shows a brittle-to-plastic transition zone in this region. Thickening in the lower crust (about 5-10 km), and rheological characteristics that show low-medium velocity (relatively reduced by 7%), suggest that crustal thickening mainly takes place in lower crust in the northeastern margin of the Tibetan plateau. The crust along the northeastern margin shows evidence of wholesale block movement, and crustal shortening and thickening seem to be the main deformation features of this region. The GPS data show that the block motion modes and crustal thickening in the Tibetan plateau is closely related to the peripheral tectonic stress field and motion direction of the Indian plate. The Mani-Yushu-Xianshuihe fold belt along the boundary between the Qiangtang block and the Bayan Har block divides the different plateau thickening tectonic environments into the middle-western plateau, the northeastern margin and the southeastern plateau.

  1. North Atlantic forcing of tropical Indian Ocean climate.

    PubMed

    Mohtadi, Mahyar; Prange, Matthias; Oppo, Delia W; De Pol-Holz, Ricardo; Merkel, Ute; Zhang, Xiao; Steinke, Stephan; Lückge, Andreas

    2014-05-01

    The response of the tropical climate in the Indian Ocean realm to abrupt climate change events in the North Atlantic Ocean is contentious. Repositioning of the intertropical convergence zone is thought to have been responsible for changes in tropical hydroclimate during North Atlantic cold spells, but the dearth of high-resolution records outside the monsoon realm in the Indian Ocean precludes a full understanding of this remote relationship and its underlying mechanisms. Here we show that slowdowns of the Atlantic meridional overturning circulation during Heinrich stadials and the Younger Dryas stadial affected the tropical Indian Ocean hydroclimate through changes to the Hadley circulation including a southward shift in the rising branch (the intertropical convergence zone) and an overall weakening over the southern Indian Ocean. Our results are based on new, high-resolution sea surface temperature and seawater oxygen isotope records of well-dated sedimentary archives from the tropical eastern Indian Ocean for the past 45,000 years, combined with climate model simulations of Atlantic circulation slowdown under Marine Isotope Stages 2 and 3 boundary conditions. Similar conditions in the east and west of the basin rule out a zonal dipole structure as the dominant forcing of the tropical Indian Ocean hydroclimate of millennial-scale events. Results from our simulations and proxy data suggest dry conditions in the northern Indian Ocean realm and wet and warm conditions in the southern realm during North Atlantic cold spells. PMID:24784218

  2. Information About Indians of Iowa.

    ERIC Educational Resources Information Center

    Toothman, Maryann; Jensen, Denise

    An intermediate or junior high level unit on Indians indigenous to Iowa focuses on history, culture, and cultural conflict between the Indians and white Americans. Many of the materials can be adapted for use in other states or for a more general unit on American Indians. Twenty lessons cover the location of Iowa; prehistoric Iowa; Indian society…

  3. 75 FR 68823 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-09

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Approved Tribal-State Class III Gaming Amendment. SUMMARY: This notice publishes approval of the Amendments to the Class III Gaming Compact (Amendment) between the State of Oregon and the Siletz Indians...

  4. 78 FR 11221 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-15

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Approved Tribal-State Class III Gaming Compact. SUMMARY: This notice publishes an extension of the gaming..., 2013. FOR FURTHER INFORMATION CONTACT: Paula L. Hart, Director, Office of Indian Gaming, Office of...

  5. 78 FR 15738 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-12

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Approved Tribal--State Class III Gaming Compact. SUMMARY: This notice publishes an extension of the gaming..., 2013. FOR FURTHER INFORMATION CONTACT: Paula L. Hart, Director, Office of Indian Gaming, Office of...

  6. 77 FR 76513 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-28

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Approved Amended Tribal-State Class III Gaming Compact taking effect. SUMMARY: This notice publishes the... CONTACT: Paula L. Hart, Director, Office of Indian Gaming, Office of the Deputy Assistant...

  7. 77 FR 43110 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-23

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Approved Tribal--State Class III Gaming Compact. SUMMARY: This notice publishes an extension of Gaming... FURTHER INFORMATION CONTACT: Paula L. Hart, Director, Office of Indian Gaming, Office of the...

  8. 75 FR 38833 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-06

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Approved Tribal-State Class III Gaming Compact. SUMMARY: This notice publishes the Approved Compact between... FURTHER INFORMATION CONTACT: Paula Hart, Director, Office of Indian Gaming, Office of the Deputy...

  9. 75 FR 8108 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-23

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Approved Tribal-State Class III Gaming Compact. SUMMARY: This notice publishes approval of the Tribal-State Compact between the Pyramid Lake Paiute Indian Tribe and the State of Nevada Governing Class III...

  10. 75 FR 55823 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-14

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of approved Tribal-State Class III Gaming Compact. SUMMARY: This notice publishes an extension of Gaming.... FOR FURTHER INFORMATION CONTACT: Paula L. Hart, Director, Office of Indian Gaming, Office of...

  11. 75 FR 61511 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-05

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Approved Tribal-State Class III Gaming Compact. SUMMARY: This notice publishes an extension of Gaming..., 2010. FOR FURTHER INFORMATION CONTACT: Paula L. Hart, Director, Office of Indian Gaming, Office of...

  12. 76 FR 8375 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-14

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Approved Tribal-State Class III Gaming Compact. SUMMARY: This notice publishes an extension of the Gaming..., 2011. FOR FURTHER INFORMATION CONTACT: Paula L. Hart, Director, Office of Indian Gaming, Office of...

  13. 76 FR 52968 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-24

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Approved Tribal--State Class III Gaming Compact. SUMMARY: This notice publishes an extension of Gaming... FURTHER INFORMATION CONTACT: Paula L. Hart, Director, Office of Indian Gaming, Office of the...

  14. 75 FR 68618 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-08

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of... the Red Cliff Band of Lake Superior Chippewas (``Tribe'') and the State of Wisconsin Gaming Compact of... CONTACT: Paula L. Hart, Director, Office of Indian Gaming, Office of the Deputy Assistant...

  15. 77 FR 45371 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-31

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Approved Tribal--State Class III Gaming Compact. SUMMARY: This notice publishes an extension of Gaming... FURTHER INFORMATION CONTACT: Paula L. Hart, Director, Office of Indian Gaming, Office of the...

  16. 77 FR 59641 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-28

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Approved Tribal-State Class III Gaming Compact. SUMMARY: This notice publishes an extension of Gaming.... FOR FURTHER INFORMATION CONTACT: Paula L. Hart, Director, Office of Indian Gaming, Office of...

  17. 76 FR 65208 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-20

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Approved Tribal--State Class III Gaming Compact. SUMMARY: This notice publishes an Approval of the Gaming..., Office of Indian Gaming, Office of the Deputy Assistant Secretary--Policy and Economic...

  18. 76 FR 33341 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-08

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Approved Tribal--State Class III Gaming Compact. SUMMARY: This notice publishes an extension of Gaming... FURTHER INFORMATION CONTACT: Paula L. Hart, Director, Office of Indian Gaming, Office of the...

  19. 78 FR 44146 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-23

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Tribal-State Class III Gaming Compact taking effect. SUMMARY: This notice publishes the Class III Amended and Restated Tribal-State Gaming Compact between the Shingle Springs Band of Miwok Indians and...

  20. 78 FR 26801 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-08

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Approved Tribal-State Class III Gaming Compact. SUMMARY: This notice publishes the approval of an amendment to the Class III Tribal-State Gaming Compact between the Menominee Indian Tribe of Wisconsin and...

  1. 76 FR 56466 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-13

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Approved Tribal--State Class III Gaming Compact. SUMMARY: This notice publishes an approval of the gaming...: September 13, 2011. FOR FURTHER INFORMATION CONTACT: Paula L. Hart, Director, Office of Indian...

  2. New Indian Tribalism. Working Paper.

    ERIC Educational Resources Information Center

    Beckmann, Kathleen

    The purposes of this paper are to identify the problems Washington State Indians face and to provide considerations that might assist in promoting the welfare and well-being of American Indians. It is stated that the major barrier to the Indian's success in American society is the attitude of the Anglo towards the Indian. Thus, the programs and…

  3. Federal Financing of Indian Education.

    ERIC Educational Resources Information Center

    Loon, Eric Van

    Since over 200 million Federal dollars are disbursed annually for American Indian education under Bureau of Indian Affairs (BIA), Elementary Secondary Education Act Title I, Indian Education Act Title IV, and Johnson O'Malley programs, it is difficult to understand the dismal state of Indian education. However, factors contributing to abuse of…

  4. Response of tropical clouds to the interannual variation of sea surface temperature

    SciTech Connect

    Fu, Rong; Liu, W.T.

    1996-03-01

    Connections between large-scale interannual variations of clouds, deep convection, atmospheric winds, vertical thermodynamic structure, and sea surface temperatures (SST) over global tropical oceans are examined. SST warming associated with El Nino significantly impacted the global tropical cloud field. Extensive variations of the total cloud field, dominated by changes of high and middle clouds, occurred in the northeastern Indian, western and central Pacific, and western Atlantic Oceans. Total cloud variation, dominated by low cloud variation, was relatively weak in the eastern Pacific and the Atlantic due to cancellation between high and low cloud changes. Destabilization of the lapse rate between 900 and 750 mb was more important in enhancing convective instability than was the change of local SST in the equatorial central Pacific during the 1987 El Nino. In the subtropical Pacific, the change of lapse rate between 900 and 750 mb associated with anomalous subsidence and the decrease of boundary-layer buoyancy due to a decrease of temperature and moisture were important in enhancing convective stability. Consequently, convection and high and middle clouds decreased in these areas. The change of low clouds in the equatoral and southeastern Atlantic correlated to local SST and SST changes in the equatorial eastern Pacific, and the increase of low clouds was consistent with the sharper inversion during the 1987 El Nino. The coherence between clouds and SST tendency shows that SST tendency leads cloud variation in the equatorial Pacific. Thus, the change of clouds does not dominate the sign of SST tendency even though the cloud change was maximum during the 1987 El Nino. In some areas of the Indian, subtropical Pacific, and North Atlantic Oceans, cloud change leads SST tendency. Cloud change might affect SST tendency in these regions. 60 refs., 12 figs., 1 tab.

  5. Indian concepts on sexuality

    PubMed Central

    Chakraborty, Kaustav; Thakurata, Rajarshi Guha

    2013-01-01

    India is a vast country depicting wide social, cultural and sexual variations. Indian concept of sexuality has evolved over time and has been immensely influenced by various rulers and religions. Indian sexuality is manifested in our attire, behavior, recreation, literature, sculptures, scriptures, religion and sports. It has influenced the way we perceive our health, disease and device remedies for the same. In modern era, with rapid globalization the unique Indian sexuality is getting diffused. The time has come to rediscover ourselves in terms of sexuality to attain individual freedom and to reinvest our energy to social issues related to sexuality. PMID:23858263

  6. 25 CFR 502.12 - Indian lands.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 2 2010-04-01 2010-04-01 false Indian lands. 502.12 Section 502.12 Indians NATIONAL INDIAN GAMING COMMISSION, DEPARTMENT OF THE INTERIOR GENERAL PROVISIONS DEFINITIONS OF THIS CHAPTER § 502.12 Indian lands. Indian lands means: (a) Land within the limits of an Indian reservation; or (b)...

  7. Glacial Refugium of Pinus pumila (Pall.) Regel in Northeastern Siberia

    SciTech Connect

    Shilo, N A; Lozhkin, A V; Anderson, P M; Brown, T A; Pakhomov, A Y; Solomatkina, T B

    2007-02-10

    One of the most glowing representatives of the Kolyma flora [1], ''Pinus pumila'' (Pall.) Regel (Japanese stone pine), is a typical shrub in larch forests of the northern Okhotsk region, basins of the Kolyma and Indigirka rivers, and high-shrub tundra of the Chukchi Peninsula. It also forms a pine belt in mountains above the forest boundary, which gives way to the grass-underbrush mountain tundra and bald mountains. In the southern Chukchi Peninsula, ''Pinus pumila'' along with ''Duschekia fruticosa'' (Rupr.) Pouzar and ''Betula middendorffii'' Trautv. et C. A. Mey form trailing forests transitional between tundra and taiga [2]. Pinus pumila pollen, usually predominating in subfossil spore-and-pollen spectra of northeastern Siberia, is found as single grains or a subordinate component (up 2-3%, rarely 10%) in spectra of lacustrine deposits formed during the last glacial stage (isotope stage 2) in the Preboreal and Boreal times of the Holocene. Sometimes, its content increases to 15-22% in spectra of lacustrine deposits synchronous to the last glacial stage near the northern coast of the Sea of Okhotsk [3], evidently indicating the proximity of Japanese stone pine thickets.

  8. 76 FR 8743 - Indian Health Professions Preparatory, Indian Health Professions Pre-Graduate and Indian Health...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-15

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HEALTH AND HUMAN SERVICES Indian Health Service Indian Health Professions Preparatory, Indian Health Professions Pre-Graduate and Indian Health Professions Scholarship Programs Announcement Type: Initial. ] CFDA Numbers: 93.971, 93.123, and 93.972. DATES:...

  9. 78 FR 78976 - Indian Health Professions Preparatory, Indian Health Professions Pre-graduate and Indian Health...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-27

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HEALTH AND HUMAN SERVICES Indian Health Service Indian Health Professions Preparatory, Indian Health Professions Pre-graduate and Indian Health Professions Scholarship Programs Announcement Type: Initial. CFDA Numbers: 93.971, 93.123, AND 93.972 Key...

  10. Tectonic evaluation of the Nubian shield of Northeastern Sudan using thematic mapper imagery

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Bechtel is nearing completion of a one-year program that uses digitally enhanced LANDSAT Thematic Mapper (TM) data to compile the first comprehensive regional tectonic map of the Proterozoic Nubian Shield exposed in the northern Red Sea Hills of northeastern Sudan. The status of significant objectives of this study are given. Pertinent published and unpublished geologic literature and maps of the northern Red Sea Hills to establish the geologic framework of the region were reviewed. Thematic mapper imagery for optimal base-map enhancements was processed. Photo mosaics of enhanced images to serve as base maps for compilation of geologic information were completed. Interpretation of TM imagery to define and delineate structural and lithogologic provinces was completed. Geologic information (petrologic, and radiometric data) was compiled from the literature review onto base-map overlays. Evaluation of the tectonic evolution of the Nubian Shield based on the image interpretation and the compiled tectonic maps is continuing.

  11. Indian craniometric variability and affinities.

    PubMed

    Raghavan, Pathmanathan; Bulbeck, David; Pathmanathan, Gayathiri; Rathee, Suresh Kanta

    2013-01-01

    Recently published craniometric and genetic studies indicate a predominantly indigenous ancestry of Indian populations. We address this issue with a fuller coverage of Indian craniometrics than any done before. We analyse metrical variability within Indian series, Indians' sexual dimorphism, differences between northern and southern Indians, index-based differences of Indian males from other series, and Indians' multivariate affinities. The relationship between a variable's magnitude and its variability is log-linear. This relationship is strengthened by excluding cranial fractions and series with a sample size less than 30. Male crania are typically larger than female crania, but there are also shape differences. Northern Indians differ from southern Indians in various features including narrower orbits and less pronounced medial protrusion of the orbits. Indians resemble Veddas in having small crania and similar cranial shape. Indians' wider geographic affinities lie with "Caucasoid" populations to the northwest, particularly affecting northern Indians. The latter finding is confirmed from shape-based Mahalanobis-D distances calculated for the best sampled male and female series. Demonstration of a distinctive South Asian craniometric profile and the intermediate status of northern Indians between southern Indians and populations northwest of India confirm the predominantly indigenous ancestry of northern and especially southern Indians. PMID:24455409

  12. Indian Craniometric Variability and Affinities

    PubMed Central

    Raghavan, Pathmanathan; Bulbeck, David; Pathmanathan, Gayathiri; Rathee, Suresh Kanta

    2013-01-01

    Recently published craniometric and genetic studies indicate a predominantly indigenous ancestry of Indian populations. We address this issue with a fuller coverage of Indian craniometrics than any done before. We analyse metrical variability within Indian series, Indians' sexual dimorphism, differences between northern and southern Indians, index-based differences of Indian males from other series, and Indians' multivariate affinities. The relationship between a variable's magnitude and its variability is log-linear. This relationship is strengthened by excluding cranial fractions and series with a sample size less than 30. Male crania are typically larger than female crania, but there are also shape differences. Northern Indians differ from southern Indians in various features including narrower orbits and less pronounced medial protrusion of the orbits. Indians resemble Veddas in having small crania and similar cranial shape. Indians' wider geographic affinities lie with “Caucasoid” populations to the northwest, particularly affecting northern Indians. The latter finding is confirmed from shape-based Mahalanobis-D distances calculated for the best sampled male and female series. Demonstration of a distinctive South Asian craniometric profile and the intermediate status of northern Indians between southern Indians and populations northwest of India confirm the predominantly indigenous ancestry of northern and especially southern Indians. PMID:24455409

  13. Indian Alcoholism and Education.

    ERIC Educational Resources Information Center

    Mitchell, Wayne; Patch, Kenneth

    1981-01-01

    Educational programs about alcohol should be presented in the formal school setting for Indian youth and in the communities for the general population. The primary outcome of these programs would be the development of self-management skills. (Author)

  14. ARIZONA INDIAN RESERVATIONS

    EPA Science Inventory

    Polygon coverage of all Indian Reservations in Arizona. Reservation boundaries are compiled from multiple sources and are derived from several different source scales. Information such as reservation type, primary tribe name and location source are included with the coverage. A...

  15. REGION 9 INDIAN RESERVATIONS

    EPA Science Inventory

    Polygon coverage of all Indian Reservations in US EPA Region 9 (California, Arizona and Nevada). Reservation boundaries are compiled from multiple sources and are derived from several different source scales. Information such as reservation type, primary tribe name and location...

  16. NEVADA INDIAN RESERVATIONS

    EPA Science Inventory

    Polygon coverage of all Indian Reservations in Nevada. Reservation boundaries are compiled from multiple sources and are derived from several different source scales. Information such as reservation type, primary tribe name and location source are included with the coverage. As...

  17. Indian Summer for Wayfarers

    ERIC Educational Resources Information Center

    Kaltenbronn, Kyra

    1977-01-01

    A recreational program involving hiking and camping emphasizes teaching young participants through archeology and adventure experiences about American Indians, their technology, and their means of survival in the wilderness. (JD)

  18. Tourism and Indian Exploitation

    ERIC Educational Resources Information Center

    French, Lawrence

    1977-01-01

    A cursory review of Federal support to the Eastern Cherokees shows that the Cherokee Historical Association and not the Cherokee Indians are the recipients and beneficiaries of many Federal grants. (JC)

  19. Seismic anisotropy of western Mexico and northeastern Tibet

    NASA Astrophysics Data System (ADS)

    Leon-Soto, Gerardo

    considered. Shear wave splitting measurements using teleseismic SKS and SKKS phases recorded by the ASCENT (A Seismic Collaborative Experiment in Northeastern Tibet) and INDEPTH-IV (International Deep Profiling of Tibet and the Himalaya, Phase IV) experiments reveal significant anisotropy in north-eastern Tibet with a large delay time of up 2.2 sec, indicating that anisotropy exists in both the lithospheric and asthenospheric mantle. The coherence between fast polarization directions of split core phases and the left-lateral slip on eastern-striking, southeastern-striking and southern-striking faults in eastern Tibet as well as the surface velocity calculated from GPS data support the idea that left-lateral shear strain is the predominant cause of the orientation of the upper mantle petrofabrics. The left-lateral motion can be best understood as a manifestation of north-striking right-lateral simple shear exerted by the eastern edge of the underthrusting Indian plate as it penetrates into Eurasia, as well as the bending of the Eastern Himalayan Syntaxis (EHS) by the foundering Burma-Andaman-Sumatra slab. Two plausible competing models are proposed for the flow of asthenosphere. In the first, the deforming lithosphere gliding over the passive asthenosphere induces flow of the asthenosphere. In the second, the asthenosphere beneath northeastern Tibet is flowing eastward in an asthenosphere channel that lies between the Ordos plateau and Sichuan basin, and around the EHS as it is being compressed between the advancing Indian continental lithosphere and the thick Tarim and Qaidam lithospheres to the north. Delay times from stations in the EHS have a maximum of 1.3 sec suggesting that although most anisotropy is residing in the lithosphere, some may be associated with flow of the asthenosphere. The retreating Burma slab induces flow that is toroidal and located exclusively around the northern edge of the slab. The curved fast directions of split shear waves for stations in the

  20. Ishi: A Yahi Indian.

    ERIC Educational Resources Information Center

    2003

    The Yahi Indians were part of a larger tribal group called the Yana. The Yahi way of life, along with the lives of many other California Indian groups, changed when European and U.S. settlers came to California. In 1872 Ishi and his family were the last of the Yahi living in the Deer Creek (California) area. By 1911 Ishi was the last surviving…

  1. Contextual view showing northeastern eucalyptus windbreak and portion of citrus ...

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

    Contextual view showing northeastern eucalyptus windbreak and portion of citrus orchard. Camera facing 118" east-southeast. - Goerlitz House, 9893 Highland Avenue, Rancho Cucamonga, San Bernardino County, CA

  2. Arctic Vortex changes alter the sources and isotopic values of precipitation in northeastern US.

    PubMed

    Puntsag, Tamir; Mitchell, Myron J; Campbell, John L; Klein, Eric S; Likens, Gene E; Welker, Jeffrey M

    2016-01-01

    Altered atmospheric circulation, reductions in Arctic sea ice, ocean warming, and changes in evaporation and transpiration are driving changes in the global hydrologic cycle. Precipitation isotopic (δ(18)O and δ(2)H) measurements can help provide a mechanistic understanding of hydrologic change at global and regional scales. To study the changing water cycle in the northeastern US, we examined the longest (1968-2010) record of precipitation isotope values, collected at the Hubbard Brook Experimental Forest in New Hampshire, US (43(°)56'N, 71(°)45'W). We found a significant reduction in δ(18)O and δ(2)H values over the 43-year record, coupled with a significant increase in d-excess values. This gradual reduction in δ(18)O and δ(2)H values unexpectedly occurred during a period of regional warming. We provide evidence that these changes are governed by the interactions among the Atlantic Multidecadal Oscillation, loss of Arctic sea ice, the fluctuating jet stream, and regular incursions of polar air into the northeastern US. PMID:26971874

  3. Taxonomic guide and historical review of starfishes in northeastern Brazil (Echinodermata, Asteroidea)

    PubMed Central

    Gondim, Anne Isabelley; Christoffersen, Martin Lindsey; Pereira Dias, Thelma Lúcia

    2014-01-01

    Abstract Presently more than 1900 species of sea stars are recognized, of which 77 are recorded for the coast of Brazil. Although the first starfish record in Brazil was published 363 years ago, our knowledge of this fauna remains unsatisfactory from a systematic and ecological point of view, particularly in the north and northeastern regions of the country. This study provides the first annotated list of sea stars from northeastern Brazil. Material described herein is housed at the collections of the Federal University of Paraíba, Federal University of Sergipe, and the Federal University of Bahia, Museum of Zoology of the University of São Paulo and Museu Nacional do Rio de Janeiro. Twenty-one species were identified, belonging to 12 genera, 10 families, and 5 orders. Descriptions of species are provided. Three new occurrences were recorded for northeast Brazil: Astropecten alligator, Luidia ludwigi scotti, and Mithrodia clavigera. Highest diversities of Asteroidea were encountered for the states of Bahia (n = 14 spp), Paraíba (n = 12 spp) and Pernambuco (n = 9 spp). No species were recorded for the states of Maranhão and Sergipe. Sandy substrates and depths below 10 m were the least sampled areas over the continental shelf. Herein we provide a first panorama on the fauna of Asteroidea occurring in the northeast region of Brazil, hopefully to function as a basic reference for biodiversity studies in this poorly studied area. PMID:25408612

  4. Arctic Vortex changes alter the sources and isotopic values of precipitation in northeastern US

    NASA Astrophysics Data System (ADS)

    Puntsag, Tamir; Mitchell, Myron J.; Campbell, John L.; Klein, Eric S.; Likens, Gene E.; Welker, Jeffrey M.

    2016-03-01

    Altered atmospheric circulation, reductions in Arctic sea ice, ocean warming, and changes in evaporation and transpiration are driving changes in the global hydrologic cycle. Precipitation isotopic (δ18O and δ2H) measurements can help provide a mechanistic understanding of hydrologic change at global and regional scales. To study the changing water cycle in the northeastern US, we examined the longest (1968–2010) record of precipitation isotope values, collected at the Hubbard Brook Experimental Forest in New Hampshire, US (43o56‧N, 71o45‧W). We found a significant reduction in δ18O and δ2H values over the 43-year record, coupled with a significant increase in d-excess values. This gradual reduction in δ18O and δ2H values unexpectedly occurred during a period of regional warming. We provide evidence that these changes are governed by the interactions among the Atlantic Multidecadal Oscillation, loss of Arctic sea ice, the fluctuating jet stream, and regular incursions of polar air into the northeastern US.

  5. Arctic Vortex changes alter the sources and isotopic values of precipitation in northeastern US

    PubMed Central

    Puntsag, Tamir; Mitchell, Myron J.; Campbell, John L.; Klein, Eric S.; Likens, Gene E.; Welker, Jeffrey M.

    2016-01-01

    Altered atmospheric circulation, reductions in Arctic sea ice, ocean warming, and changes in evaporation and transpiration are driving changes in the global hydrologic cycle. Precipitation isotopic (δ18O and δ2H) measurements can help provide a mechanistic understanding of hydrologic change at global and regional scales. To study the changing water cycle in the northeastern US, we examined the longest (1968–2010) record of precipitation isotope values, collected at the Hubbard Brook Experimental Forest in New Hampshire, US (43o56′N, 71o45′W). We found a significant reduction in δ18O and δ2H values over the 43-year record, coupled with a significant increase in d-excess values. This gradual reduction in δ18O and δ2H values unexpectedly occurred during a period of regional warming. We provide evidence that these changes are governed by the interactions among the Atlantic Multidecadal Oscillation, loss of Arctic sea ice, the fluctuating jet stream, and regular incursions of polar air into the northeastern US. PMID:26971874

  6. Aeolian Sediments on the northeastern Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Stauch, G.; Lehmkuhl, F.

    2013-12-01

    The timing and spatial distribution of aeolian sediments on the northeastern Tibetan Plateau have gained increasing interest during the last decades. The formation of the aeolian deposits is often related to cold and dry climate conditions. However, further important parameters are the local geomorphological setting and sediment availability in the source areas of the sediments. Aeolian sediments including loess, sandy loess and sands are widespread in the catchment of the Donggi Cona on the northeastern Tibetan Plateau at around 4000 m asl. Detailed geomorphological mapping of the deposits and geochemical analyses of the sediments revealed varying sources throughout the Holocene. The timing of the sediment deposition is based on 43 OSL (optical stimulated luminescence) ages. Several phases of enhanced aeolian deposition took place during the Holocene. The accumulation of aeolian sands lasted from 10.5 until 7 ka. The main source area of these sands was a large alluvial fan. Parallel to the formation of the dunes loess was deposited on the adjacent slopes from 10.5 until 7.5 ka. These sediments most probably originate in the nearby Qaidam Basin. In contrast to the general linkage of aeolian sediments to dryer climate conditions formation of these aeolian deposits is related to wetter conditions due to a strengthening of the Asian Summer Monsoons. The wetter climate enhanced the trapping and continuous fixation of the aeolian sediments by vegetation. With the further strengthening of the Monsoon fluvial processes eroded the aeolian deposits at least until 6 ka. From about 3 ka to the present a reactivation of aeolian sands and the formation of new dunes took place. This reactivation is related to drier conditions on the north-eastern Tibetan Plateau. Additionally, an increased human influence might have enhanced the aeolian activity. Similar phases of enhanced aeolian activity have been documented in more than 170 available OSL ages from loess and aeolian sands in

  7. Mesoscale variability of water masses in the Arabian Sea as revealed by ARGO floats

    NASA Astrophysics Data System (ADS)

    Carton, X.; L'Hegaret, P.; Baraille, R.

    2012-03-01

    By analysing ARGO float data over the last four years, a few aspects of the mesoscale variability of water masses in the Arabian Sea are described. The Red Sea Outflow Water (RSOW) is concentrated in the Southwestern Gulf of Aden, in particular when a cyclonic gyre predominates in this region. Salinities of 36.5 and temperatures of 16 °C are found in this area at depths between 600 and 1000 m. RSOW is more dilute in the eastern part of the Gulf, where intense and relatively barotropic gyres mix it with Indian ocean Central Water. RSOW is also detected along the northeastern coast of Socotra, and fragments of RSOW are found between one and three degrees of latitude north of this island. In the whole Gulf of Aden, the correlation between the deep motions of the floats and the sea-level anomaly measured by altimetry is strong, at regional scale. The finer scale details of the float trajectories are not sampled by altimetry and are often related to the anomalous water masses that the floats encounter. The Persian Gulf Water (PGW) is found in the float profiles near Ras ash Sharbatat (near 57° E, 18° N), again with 36.5 in salinity and about 18-19 °C in temperature. These observations were achieved in winter when the southwestward monsoon currents can advect PGW along the South Arabian coast. Fragments of PGW were also observed in the Arabian Sea between 18 and 20° N and 63 and 65° E in summer, showing that this water mass can escape the Gulf of Oman southeastward, during that season. Kinetic energy distributions of floats with respect to distance or angle share common features between the two regions (Gulf of Aden and Arabian Sea), in particular peaks at 30, 50 and 150 km scales and along the axis of monsoon currents. Hydrological measurements by floats are also influenced by the seasonal variations of PGW and RSOW in these regions.

  8. Holocene climatic variations documented by multiple biomarker proxies from Lake Gahai on the Northeastern Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    He, Y.; Liu, Z.; Zheng, Z.; Zhao, C.; Sun, Y.

    2012-12-01

    The Northeastern Tibetan Plateau is a high elevation region sensitive to large-scale climate change, thus allows us better understanding the Holocene climate interactions between the mid-latitude westerly and subtropical Asia monsoon circulations. This region is now and in the late Holocene out of the influence of Asian monsoon systems and inconsistency hydrological variations from monsoon controlled region is suggested. However, the boundary and the interactions between the westerly and the Asian monsoon circulations during the whole Holocene have not been well documented. Here we present multiple biomarker alkane and alkenone based records from Lake Gahai in the Qaidam Basin on the northeastern Tibetan Plateau to study the lake level and climate variability over the past 12,000 years. Characterized by marked alkane-based average chain length (ACL) and carbon preference index (CPI) values, our records provide unambiguous evidence of a generally dry climate from 9 to 2 ka (1 ka = 1,000 cal yr BP), and a relatively wet climate after 2 ka and before 9 ka. The occurrence of alkenones during the period of low ACL and CPI values also supports this result. Good match between our records and other earlier paleoclimatic records derived from the same basin was found, suggesting the paleoenvironment record obtained at Lake Gahai is a regional record rather than a local signal, at least in the Qaidam Basin. This generally dry climate between 9 and 2 ka was almost synchronous with the weakening of East Asian and Indian monsoon intensities. However, our data suggest an opposite moisture relation from our region and westerly controlled region. This phenomenon may lie on the interaction between westerly and monsoon systems, probably contributed to the topographic subsidence associated with stronger atmospheric convergence and rising motion on the plateau. Also this discrepancy was likely due to the enhanced evaporation than to the increased monsoon precipitation in the

  9. 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.

  10. Halocoryza Alluaud 1919, sea-side beetles of the Indian, Atlantic (sensu lato), and Pacific Oceans: a generic synopsis and description of a remarkable new species from Baja California Sur, México (Coleoptera, Carabidae, Scaritini, Clivinina).

    PubMed

    Erwin, Terry L

    2011-01-01

    Information on the three previously described species of Halocoryza Alluaud is updated and a new species for the genus from Isla Carmen, Sea of Cortés, Baja California Sur, México is described. Halocoryza whiteheadianasp. n. was found at UV light on a beach of that island. This species does not fit the profile of the other three species, i.e., living on coralline beach sands, or in the Mangrove intertidal zone. Two alternative possibilities as to why this is so are suggested and a study plan for testing these possibilities is proposed. PMID:21998544

  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. Hydrography and through-flow in the north-eastern North Atlantic Ocean: the NANSEN project

    NASA Astrophysics Data System (ADS)

    van Aken, H. M.; Becker, G.

    The circulation and hydrography of the north-eastern North Atlantic has been studied with an emphasis on the upper layers and the deep water types which take part in the thermohaline overturning of the Oceanic Conveyor Belt. Over 900 hydrographic stations were used for this study, mainly from the 1987-1991 period. The hydrographic properties of Subpolar Mode Water in the upper layer, which is transported towards the Norwegian Sea, showed large regional variation. The deep water mass was dominated by the cold inflow of deep water from the Norwegian Sea and by a cyclonic recirculation of Lower Deep Water with a high Antarctic Bottom Water content. At intermediate levels the dominating water type was Labrador Sea Water with only minor influence of Mediterranean Sea Water. In the permanent pycnocline traces of Antarctic Intermediate Water were found. Geostrophic transports have been estimated, and these agreed in order of magnitude with the local heat budget, with current measurements, with data from surface drifters, and with the observed water mass modification. A total of 23 Sv of surface water entered the region, of which 20 Sv originated from the North Atlantic Current, while 3 Sv entered via an eastern boundary current. Of this total, 13 Sv of surface water left the area across the Reykjanes Ridge, and 7 Sv entered the Norwegian Sea, while 3 Sv was entrained by the cold overflow across the Iceland-Scotland Ridge. Approximately 1.4 Sv of Norwegian Sea Deep Water was involved in the overflow into the Iceland Basin, which, with about 1.1 Sv of entrained water and 1.1 Sv recirculating Lower Deep Water, formed a deep northern boundary current in the Iceland Basin. At intermediate depths, where Labrador Sea Water formed the dominant water type, about 2 Sv of entrained surface water contributed to a saline water mass which was transported westwards along the south Icelandic slope.

  15. Resources for Teaching About American Indians.

    ERIC Educational Resources Information Center

    Parisi, Lynn

    1987-01-01

    Lists selected resources for teaching about American Indians available from the ERIC database. Topics of resources include Navajo history, Pacific Northwest history, Indians of Oklahoma, Indian traditions, Plains Indian culture, and Pawnee history. (AEM)

  16. The impacts of Middle East dust on Indian summer rainfall

    NASA Astrophysics Data System (ADS)

    Jin, Q.; Yang, Z. L.; Wei, J.

    2014-12-01

    Using the Weather Research and Forecasting model with online chemistry (WRF-Chem), the impact of Middle East dust aerosols on the Indian summer monsoon rainfall was studied. Eight numerical experiments were conducted to take into account uncertainties related to dust-absorbing properties, various assumptions used in calculating aerosol optical depth (AOD), and various radiation schemes. In order to obtain reasonable dust emission, model-simulated AOD and radiation forcing at the top of the atmosphere were compared with multiple satellite- and surface-based observations. Consistent with observations, modeled results show heavy dust loadings in the Arabian Peninsula and Pakistan, which can be transported through long distance to the Arabian Sea and the Indian Peninsula. By heating the atmosphere in the lower troposphere over the Iranian Plateau, these dust aerosols result in strengthened Indian summer monsoon circulations, which in turn transport more water vapor to the Indian Peninsula. The model shows that northern India becomes wetter during the monsoon season in dust cases than non-dust cases. Further observational analyses show an increasing trend in AOD over the Arabian Peninsula, which corresponds to an increasing trend of rainfall in northern India during summer monsoon seasons from 2000 to 2013. These observed trends of AOD and rainfall are consistent with the model-simulated positive relationship between Middle East dust and Indian summer monsoon rainfall. Our results highlight long-term (decadal) impacts of Middle East dust aerosols on the Indian summer rainfall.

  17. Water vapor budget of the Indian monsoon depression

    NASA Astrophysics Data System (ADS)

    Yoon, Jin-Ho; Chen, Tsing-Chang

    2005-10-01

    Estimations by previous studies show that a minor amount of the Indian monsoon rainfall is contributed by Indian monsoon depressions (IMDs). In contrast, other studies found that approximately half of the summer monsoon rainfall in the northern Indian subcontinent is generated by IMDs. IMDs occur an average of six times during the summer season and provide a crucial water source to the agricultural activity over this region. The large disparity in the estimation of the IMD contribution to the Indian rainfall by previous studies requires a more accurate water vapor budget analysis of the IMD with quality data. For this reason, a composite analysis of the IMD is performed using the ERA-40 reanalysis and four precipitation data sets (the Global Precipitation Climatology Project, the Tropical Rainfall Measuring Mission, the GEOS precipitation index at the Goddard Space Flight Center and surface station observations) for the period of 1979 2002. Important findings of this study are: (i) about 45 55% of the total Indian rainfall is produced by the IMD; (ii) the rainfall maximum in the west south-west sector of IMDs is largely maintained by convergence of atmospheric water vapor flux. The convergence of water vapor flux is largely coupled with the lower-tropospheric divergent circulation. Thus, the IMD water vapor budget is modulated by the 30 60 and 10 20 d monsoon modes through changes of water vapor convergence/divergence. The magnitude of this modulation on the IMD water vapor budget is close to a quarter of the summer-mean water vapor budget over the Bay of Bengal and north-eastern India.

  18. The ophiolite belts of northeastern China

    NASA Astrophysics Data System (ADS)

    Congzhou, Cao

    Four ophiolite belts, i.e. the Wendur Miao-Xar Moron River, the Solon Mt.-Hegen Mt., the Mudangjiang and the Raohe ophiolite belts, are recognized in northeastern China in various tectogenetic environments, with different ages and geological significance. They may be present in the Upper Proterozoic, lower Lower Paleozoic, lower Upper Paleozoic or Triassic, respectively. They are also formed in oceanic basin, mid-oceanic ridge, island-arc and back-arc basin, and either within plate or between two plates respectively.

  19. Recent sedimentation, northeastern Port Valdez, Alaska

    NASA Astrophysics Data System (ADS)

    Palmer, Harold D.

    1981-09-01

    Sediments accumulating on the northeastern shore of Port Valdez, a fjord leading to Prince William Sound in southern Alaska, are derived from both deltaic and alluvial fan processes. The resulting thick wedge of Recent silts, sands, shells and gravels lies atop irregular ridges of local graywacke bedrock and scattered till deposits. Seismic reflection profiling augmented by soil borings indicates that rapid infilling and upbuilding has occurred at this site. Evidence of slumping suggests general instability of steep submarine slopes in an area characterized by strong earthquakes and large tidal ranges.

  20. Examining the Validity of the Indian Summer Singularity across the Northeast United States

    NASA Astrophysics Data System (ADS)

    Godek, M. L.

    2010-12-01

    Atmospheric singularities like the January Thaw and Indian Summer have a rich history in United States folklore, particularly in the Northeast. While many people across the country may question or take interest in the year-to-year arrival of Indian Summer, the information on these repetitive weather events is sparse and generally limited to non-science resources or those without a rigorous peer review process. Further, the vast majority of scientific literature in existence on the phenomena was conducted prior to 1990. This leaves atmospheric and earth scientists with a considerable lack of recent scientific knowledge, investigation, documentation and evidence supporting the Indian Summer phenomena as a true observed singularity. The goal of this research is to identify and examine the Indian Summer singularity across the Northeastern United States region. A statistical approach to the assessment of maximum, minimum and mean temperature records is used to pinpoint the Indian Summer singularity at 20 stations over that past 50 years. Applicable weather criteria used to define the singularity in past works are addressed here and new criteria are proposed for the Northeast region. The singularity is examined from a spatial and temporal perspective so that the timing of Indian Summer across the region, and its specific locations within those periods, may be identified. Results indicate that Indian Summer is a valid autumnal, multi-day singularity that is especially evident in a seasonal record. However, in the annual cycle most Indian Summers appear within natural seasonal variability bounds, or within one standard deviation from long-term mean temperatures. Example of a single-day Indian Summer event at Portland, Maine.

  1. Young Once, Indian Forever: Youth Gangs in Indian Country

    ERIC Educational Resources Information Center

    Bell, James; Lim, Nicole

    2005-01-01

    Not unlike mainstream society of the United States, Indian Country faces new challenges regarding the values, mores, and behavior of its young people. Since their first encounters with European explorers, American Indians have fought to preserve their culture and traditions. Federal policies that addressed the "Indian problem" by establishing…

  2. The Horse and the Plains Indian. Indian Culture Series.

    ERIC Educational Resources Information Center

    Schuessler, Raymond

    Produced by the Montana Council for Indian Education as part of its Indian Culture Series, the five short articles in the book explain how the Plains Indians got horses in legend and in fact. The stories describe the behavior codes, rules, cultural and social significance, and eventual cessation of horse raids, and the ceremony and tradition…

  3. Indian Tales of the Northern Rockies. Indian Culture Series.

    ERIC Educational Resources Information Center

    Old Coyote, Sally; Toineeta, Joy Yellowtail

    Part of the Montana Council for Indian Education's Indian Culture Series, the book contains six folk stories recorded on reservations and by headstart teachers. The stories are: "The Owl", a Gros Ventre tale; "How the Robin Got a Red Breast", from the Flathead Tribe; "Old Man Coyote and the Wild Geese", a Crow Indian folk story; "How the Animals…

  4. 78 FR 10203 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-13

    ... III Tribal- State Gaming Compact between the Chippewa-Cree Tribe of the Rocky Boy's Indian Reservation... Chippewa-Cree Indians of the Rocky Boy's Reservation and the State of Montana submitted a Class III...

  5. Hamlin Garland and the Indian

    ERIC Educational Resources Information Center

    Underhill, Lonnie E.

    1974-01-01

    Written to stimulate interest in an evaluation of Hamlin Garland's total production of work on the American Indian, this article suggests a reevaluation of some of Garland's work in light of the current interest in American Indian studies. (JC)

  6. Teaching about Indians? Use the Real Stuff!

    ERIC Educational Resources Information Center

    Feldkamp-Price, Betsy; Smith, David Lee

    1994-01-01

    Provides suggestions for teaching students about American Indians. Teachers need to learn more about Indians; confront misconceptions and stereotypes; have students make Indian crafts and foods; play Indian games; learn about contemporary Indian culture; be critical of resources; and contact local Indian or cultural groups. (MDM)

  7. Atlantic and indian oceans pollution in africa

    NASA Astrophysics Data System (ADS)

    Abubakar, Babagana

    Africa is the second largest and most populated continent after Asia. Geographically it is located between the Atlantic and Indian Oceans. Most of the Africa's most populated and industrialized cities are located along the coast of the continent facing the Atlantic and Indian Oceans, example of such cities include Casablanca, Dakar, Accra, Lagos, Luanda and Cape town all facing the Atlantic Ocean and cities like East London, Durban, Maputo, Dar-es-salaam and Mogadishu are all facing the Indian Ocean. As a result of the geographical locations of African Coastal Cities plus increase in their population, industries, sea port operations, petroleum exploration activities, trafficking of toxic wastes and improper waste management culture lead to the incessant increase in the pollution of the two oceans. NATURE OF POLLUTION OF THE ATLANTIC OCEAN i. The petroleum exploration activities going on along the coast of "Gulf of Guinea" region and Angola continuously causes oil spillages in the process of drilling, bunkering and discharging of petroleum products in the Atlantic Ocean. ii. The incessant degreasing of the Sea Ports "Quay Aprons" along the Coastal cities of Lagos, Luanda, Cape Town etc are continuously polluting the Atlantic Ocean with chemicals. iii. Local wastes generated from the houses located in the coastal cities are always finding their ways into the Atlantic Ocean. NATURE OF POLLUTION OF THE INDIAN OCEAN i. Unlike the Atlantic ocean where petroleum is the major pollutant, the Indian Ocean is polluted by Toxic / Radioactive waste suspected to have been coming from the developed nations as reported by the United Nations Environmental Programme after the Tsunami disaster in December 2004 especially along the coast of Somalia. ii. The degreasing of the Quay Aprons at Port Elizabeth, Maputo, Dar-es-Salaam and Mongolism Sea Ports are also another major source polluting the Indian Ocean. PROBLEMS GENERATED AS A RESULT OF THE OCEANS POLLUTION i. Recent report

  8. Atlantic and Indian Oceans Pollution in Africa

    NASA Astrophysics Data System (ADS)

    Abubakar, B.

    2007-05-01

    Africa is the second largest and most populated continent after Asia. Geographically it is located between the Atlantic and Indian Oceans. Most of the Africa's most populated and industrialized cities are located along the coast of the continent facing the Atlantic and Indian Oceans, example of such cities include Casablanca, Dakar, Accra, Lagos, Luanda and Cape town all facing the Atlantic Ocean and cities like East London, Durban, Maputo, Dar-es-salaam and Mogadishu are all facing the Indian Ocean. As a result of the geographical locations of African Coastal Cities plus increase in their population, industries, sea port operations, petroleum exploration activities, trafficking of toxic wastes and improper waste management culture lead to the incessant increase in the pollution of the two oceans. NATURE OF POLLUTION OF THE ATLANTIC OCEAN i. The petroleum exploration activities going on along the coast of "Gulf of Guinea" region and Angola continuously causes oil spillages in the process of drilling, bunkering and discharging of petroleum products in the Atlantic Ocean. ii. The incessant degreasing of the Sea Ports "Quay Aprons" along the Coastal cities of Lagos, Luanda, Cape Town etc are continuously polluting the Atlantic Ocean with chemicals. iii. Local wastes generated from the houses located in the coastal cities are always finding their ways into the Atlantic Ocean. NATURE OF POLLUTION OF THE INDIAN OCEAN i. Unlike the Atlantic ocean where petroleum is the major pollutant, the Indian Ocean is polluted by Toxic / Radioactive waste suspected to have been coming from the developed nations as reported by the United Nations Environmental Programme after the Tsunami disaster in December 2004 especially along the coast of Somalia. ii. The degreasing of the Quay Aprons at Port Elizabeth, Maputo, Dar-es-Salaam and Mongolism Sea Ports are also another major source polluting the Indian Ocean. PROBLEMS GENERATED AS A RESULT OF THE OCEANS POLLUTION i. Recent report

  9. Patterns of Mass Mortality among Rocky Shore Invertebrates across 100 km of Northeastern Pacific Coastline.

    PubMed

    Jurgens, Laura J; Rogers-Bennett, Laura; Raimondi, Peter T; Schiebelhut, Lauren M; Dawson, Michael N; Grosberg, Richard K; Gaylord, Brian

    2015-01-01

    Mass mortalities in natural populations, particularly those that leave few survivors over large spatial areas, may cause long-term ecological perturbations. Yet mass mortalities may remain undocumented or poorly described due to challenges in responding rapidly to unforeseen events, scarcity of baseline data, and difficulties in quantifying rare or patchily distributed species, especially in remote or marine systems. Better chronicling the geographic pattern and intensity of mass mortalities is especially critical in the face of global changes predicted to alter regional disturbance regimes. Here, we couple replicated post-mortality surveys with preceding long-term surveys and historical data to describe a rapid and severe mass mortality of rocky shore invertebrates along the north-central California coast of the northeastern Pacific Ocean. In late August 2011, formerly abundant intertidal populations of the purple sea urchin (Strongylocentrotus purpuratus, a well-known ecosystem engineer), and the predatory six-armed sea star (Leptasterias sp.) were functionally extirpated from ~100 km of coastline. Other invertebrates, including the gumboot chiton (Cryptochiton stelleri) the ochre sea star (Pisaster ochraceus), and subtidal populations of purple sea urchins also exhibited elevated mortality. The pattern and extent of mortality suggest the potential for long-term population, community, and ecosystem consequences, recovery from which may depend on the different dispersal abilities of the affected species. PMID:26039349

  10. Patterns of Mass Mortality among Rocky Shore Invertebrates across 100 km of Northeastern Pacific Coastline

    PubMed Central

    Jurgens, Laura J.; Rogers-Bennett, Laura; Raimondi, Peter T.; Schiebelhut, Lauren M.; Dawson, Michael N.; Grosberg, Richard K.; Gaylord, Brian

    2015-01-01

    Mass mortalities in natural populations, particularly those that leave few survivors over large spatial areas, may cause long-term ecological perturbations. Yet mass mortalities may remain undocumented or poorly described due to challenges in responding rapidly to unforeseen events, scarcity of baseline data, and difficulties in quantifying rare or patchily distributed species, especially in remote or marine systems. Better chronicling the geographic pattern and intensity of mass mortalities is especially critical in the face of global changes predicted to alter regional disturbance regimes. Here, we couple replicated post-mortality surveys with preceding long-term surveys and historical data to describe a rapid and severe mass mortality of rocky shore invertebrates along the north-central California coast of the northeastern Pacific Ocean. In late August 2011, formerly abundant intertidal populations of the purple sea urchin (Strongylocentrotus purpuratus, a well-known ecosystem engineer), and the predatory six-armed sea star (Leptasterias sp.) were functionally extirpated from ~100 km of coastline. Other invertebrates, including the gumboot chiton (Cryptochiton stelleri) the ochre sea star (Pisaster ochraceus), and subtidal populations of purple sea urchins also exhibited elevated mortality. The pattern and extent of mortality suggest the potential for long-term population, community, and ecosystem consequences, recovery from which may depend on the different dispersal abilities of the affected species. PMID:26039349

  11. Indian womanhood: some psychological concepts.

    PubMed

    De Sousa, Dhanalakshmi; De Sousa, Avinash

    2015-01-01

    Indian womanhood today is at crossroads. The present paper discusses the status of Indian womanhood and its psychological underpinnings. It discusses how Indian women have suffered at the hands of their families and society leaving no path but to succumb to psychiatric illness. The role of mental health professionals and family members in supporting and promoting growth and development of the Indian woman is outlined. PMID:25838719

  12. Indian Womanhood: Some Psychological Concepts*

    PubMed Central

    De Sousa, Dhanalakshmi; De Sousa, Avinash

    2015-01-01

    Indian womanhood today is at crossroads. The present paper discusses the status of Indian womanhood and its psychological underpinnings. It discusses how Indian women have suffered at the hands of their families and society leaving no path but to succumb to psychiatric illness. The role of mental health professionals and family members in supporting and promoting growth and development of the Indian woman is outlined. PMID:25838719

  13. Indian Child Welfare in Montana.

    ERIC Educational Resources Information Center

    Dull Knife Memorial Coll., Lame Deer, MT.

    This report is based upon a 1985-86 survey conducted by the Dull Knife Memorial College Indian Child Welfare Project. A series of workshops were conducted throughout Montana to acquaint providers of services for abused and neglected Indian children with the requirements of and issues associated with the Indian Child Welfare Act of 1978.…

  14. The American Indian: A Microcourse.

    ERIC Educational Resources Information Center

    Glick, Norman; And Others

    Designed for secondary students and dealing with the concept of ethnicity in an urban setting, this microcourse on the American Indian presents general information on American Indians and an in-depth study of Indians within the Chicago, Illinois area. Included in this curriculum guide are: seven specific behavioral objectives; course content (some…

  15. Directory of American Indian Tribes.

    ERIC Educational Resources Information Center

    Northern Arizona Univ., Flagstaff. Inst. for Human Development.

    This directory provides general information on American Indian and Alaska Native tribes and lands. The information was compiled from several resources including the "Federal Register," the Bureau of Indian Affairs, "The Native American Almanac" (A. Hirschfelder, M. K. de Montano), the "Atlas of North American Indian Tribes" (Carl Waldman), the…

  16. Literature of the Indian Subcontinent.

    ERIC Educational Resources Information Center

    Dimock, Edward C., Jr.

    Indian literature is intimately bound up with the Indian religious system. The earliest sacred writings are the Vedas. In addition to being poetry on nature, and later on, ritual formulae for controlling the universe, the Vedas have philosophical speculation. A large part of classical Indian literature consists of writing commentaries on…

  17. Title IV: Improving Indian Education.

    ERIC Educational Resources Information Center

    Barker, Kipp A.

    The Indian Education Act of 1972, Title IV, has improved Native American education by emphasizing Native American control; it comes after 400 years of Euro-American involvement in Indian education during which assimilation was the primary goal. In 1568 Jesuit priests began "civilizing" and Christianizing the "savage" Indians; in 1794 the first…

  18. The Indian in American History.

    ERIC Educational Resources Information Center

    Vogel, Virgil J.

    The treatment of American Indians is discussed historically with reference to the 4 principal methods used to create or perpetuate false impressions: obliteration, defamation, disembodiment, and disparagement. Indian contributions to American civilization are cited in contrast with historical references to Indians in textbooks. The author suggests…

  19. 78 FR 33435 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-04

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Approved Tribal-State Class III Gaming Amendments. SUMMARY: This notice publishes approval of an Agreement to Amend the Class III Tribal-State Gaming Compact between the Salt River Pima- Maricopa...

  20. 78 FR 54670 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-05

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of extension of Tribal--State Class III Gaming Compact. SUMMARY: This publishes notice of the Extension of the Class III gaming compact between the Yankton Sioux Tribe and the State of South Dakota. DATES:...

  1. 77 FR 30550 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-23

    ... of Approval in the Federal Register on February 23, 2010 (47 FR 44678). This agreement allows for the... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Approved Tribal--State Class III Gaming Compact. SUMMARY: This notice publishes approval by the...

  2. 78 FR 17427 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-21

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Approved Tribal-State Class III Gaming Compact. SUMMARY: This notice publishes approval of the agreement between the Northern Cheyenne Tribe and the State of Montana concerning Class III Gaming (Compact)....

  3. 76 FR 49505 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-10

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Approved Tribal-State Class III Gaming Compact. SUMMARY: This notice publishes an extension of the Tribal-State gaming compact between the Oglala Sioux Tribe and the State of South Dakota. DATES: Effective...

  4. 76 FR 49505 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-10

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Tribal-State Class III Gaming Compact taking effect. SUMMARY: This publishes notice of the Tribal-State... Gaming, Office of the Deputy Assistant Secretary--Policy and Economic Development, Washington, DC...

  5. 77 FR 41200 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-12

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Approved Tribal--State Class III Gaming Compact. SUMMARY: This notice publishes approval by the Department of an extension to the Class III Gaming Compact between the State of California and the...

  6. 77 FR 76514 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-28

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Approved Tribal-State Class III Gaming Compact taking effect. SUMMARY: This notice publishes the Approval of the Amendment to the Amended and Restated Tribal-State Compact for Regulation of Class III...

  7. 78 FR 62649 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-22

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Tribal-State Class III Gaming Compact taking effect. SUMMARY: This notice publishes the Class III Gaming... Gaming, Office of the Deputy Assistant Secretary--Policy and Economic Development, Washington, DC...

  8. 78 FR 54908 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-06

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of approved Tribal-State Class III Gaming Compact. SUMMARY: This notice publishes the approval of the Class III Tribal- State Gaming Compact between the Wiyot Tribe and the State of California. DATES:...

  9. 77 FR 5566 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-03

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Tribal--State Class III Gaming Compact Taking Effect. SUMMARY: This publishes notice of the Tribal-State... Gaming, Office of the Deputy Assistant Secretary--Policy and Economic Development, Washington, DC...

  10. 78 FR 17428 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-21

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Approved Tribal-State Class III Gaming Compact. SUMMARY: This notice publishes the approval of the Class III Tribal- State Gaming Compact between the Pyramid Lake Paiute Tribe and the State of...

  11. 78 FR 17427 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-21

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ] ACTION: Notice of Approved Amended Gaming Compact. SUMMARY: This notice publishes the approval of the Amended Gaming Compact between the Sisseton-Wahpeton Sioux Tribe and the State of North Dakota; the Amended Gaming...

  12. 78 FR 62650 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-22

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of extension of Tribal-State Class III Gaming Compact. SUMMARY: This publishes notice of the extension of the Class III gaming compact between the Rosebud Sioux Tribe and the State of South Dakota. DATES:...

  13. 78 FR 62649 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-22

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ACTION: Notice of Approved Tribal-State Class III Gaming Compact. SUMMARY: This notice publishes the approval of an amendment to the Class III Tribal-State Gaming Compact (Amendment), between the Tunica- Biloxi Tribe...

  14. 78 FR 78377 - Indian Gaming

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-26

    ... Bureau of Indian Affairs Indian Gaming AGENCY: Bureau of Indian Affairs, Interior. ] ACTION: Notice of extension of Tribal-State Class III Gaming Compact. SUMMARY: This publishes notice of the extension of the Class III gaming compact between the Yankton Sioux Tribe and the State of South Dakota. DATES:...

  15. Facts about American Indian Education

    ERIC Educational Resources Information Center

    American Indian College Fund, 2010

    2010-01-01

    As a result of living in remote rural areas, American Indians living on reservations have limited access to higher education. One-third of American Indians live on reservations, according to the U.S. Census Bureau. According to the most recent U.S. government statistics, the overall poverty rate for American Indians/Alaska Natives, including…

  16. A History of Indian Education.

    ERIC Educational Resources Information Center

    Reyhner, Jon; Eder, Jeanne

    The goal of assimilating American Indians into an alien culture seemed inevitable as superior weaponry and foreign diseases conquered the Indians. Only in the 20th century has serious consideration been given to allowing Indians to choose their own destiny. Using many excerpts from historical accounts, this book describes educational efforts by…

  17. Holocene cyclic climatic variations and the role of the Pacific Ocean as recorded in varved sediments from northeastern China

    NASA Astrophysics Data System (ADS)

    Chu, Guoqiang; Sun, Qing; Xie, Manman; Lin, Yuan; Shang, Wenyu; Zhu, Qingzen; Shan, Yabing; Xu, Deke; Rioual, Patrick; Wang, Luo; Liu, Jiaqi

    2014-10-01

    We present an n-alkane and compound-specific carbon isotope record of the past 9 ka from the annually laminated sedimentary sequence of Lake Xiaolongwan, northeastern China. The n-alkane distribution suggests that Lake Xiaolongwan has undergone a shift from an oligotrophic state with low algal production and little emergent/submerged macrophytes in the early Holocene, to a eutrophic state with high algal production and abundant emergent/submerged macrophytes since the middle Holocene. The pattern of variation observed in the biomarker proxies ACL (the n-alkane average chain length), Paq (aquatic macrophyte versus aquatic macrophyte and terrestrial plant ratio), and LPTP (lake productivity/terrigenous organic production) is throughout the record similar to that of the total organic carbon. The variation of compound-specific carbon isotopic values in the middle- and short-chain alkanes was mainly regulated by lake productivity and the accumulating organic pool through time. In this forested region, where the vegetation is dominated by C3 plants, the long-chain n-alkanes (C27-C31) are predominantly derived from leaf wax lipids. The compound-specific δ13C27-31 value is sensitive to effective precipitation, and therefore represents a useful indicator of regional monsoonal precipitation. Spectral analysis on the δ13C27-31 time series reveals significant periodicities of 87-89, 205-212, 1020-1050 and 1750-2041 years. On the centennial timescale, the quasi-periodicities around 88 and 210 years suggest a strong link between solar activity and monsoon rainfall. The millennial monsoon cycle in northeastern China is associated with sea surface temperature (SST) variations in two active centers of the summer monsoon, the western Pacific Subtropical High (WPSH) and the Okhotsk High. Increasing SST in the subtropical sea may cause a northwards shift of the WPSH, which extends the monsoon rain band (Meiyu) to northeastern China, and thus increasing rainfall in that region

  18. Resisting the Script of Indian Education: Zitkala Sa and the Carlisle Indian School.

    ERIC Educational Resources Information Center

    Enoch, Jessica

    2002-01-01

    Offers a "definition" of Zitkala Sa as an Indian teacher who, at the turn of the 20th century, challenged and countered educational norms that silenced Indian voices and erased Indian culture. Examines her autobiographical essays, "Impressions of an Indian Childhood,""The School Days of an Indian Girl," and "An Indian Teacher among Indians," in…

  19. An Ensemble Weighting Approach for Dendroclimatology: Drought Reconstructions for the Northeastern Tibetan Plateau

    PubMed Central

    Fang, Keyan; Wilmking, Martin; Davi, Nicole; Zhou, Feifei; Liu, Changzhi

    2014-01-01

    Traditional detrending methods assign equal mean value to all tree-ring series for chronology developments, despite that the mean annual growth changes in different time periods. We find that the strength of a tree-ring model can be improved by giving more weights to tree-ring series that have a stronger climate signal and less weight to series that have a weaker signal. We thus present an ensemble weighting method to mitigate these potential biases and to more accurately extract the climate signals in dendroclimatology studies. This new method has been used to develop the first annual precipitation reconstruction (previous August to current July) at the Songmingyan Mountain and to recalculate the tree-ring chronology from Shenge site in Dulan area in northeastern Tibetan Plateau (TP), a marginal area of Asian summer monsoon. The ensemble weighting method explains 31.7% of instrumental variance for the reconstructions at Songmingyan Mountain and 57.3% of the instrumental variance in the Dulan area, which are higher than those developed using traditional methods. We focus on the newly introduced reconstruction at Songmingyan Mountain, which showsextremely dry (wet) epochs from 1862–1874, 1914–1933 and 1991–1999 (1882–1905). These dry/wet epochs were also found in the marginal areas of summer monsoon and the Indian subcontinent, indicating the linkages between regional hydroclimate changes and the Indian summer monsoon. PMID:24497967

  20. An ensemble weighting approach for dendroclimatology: drought reconstructions for the northeastern Tibetan Plateau.

    PubMed

    Fang, Keyan; Wilmking, Martin; Davi, Nicole; Zhou, Feifei; Liu, Changzhi

    2014-01-01

    Traditional detrending methods assign equal mean value to all tree-ring series for chronology developments, despite that the mean annual growth changes in different time periods. We find that the strength of a tree-ring model can be improved by giving more weights to tree-ring series that have a stronger climate signal and less weight to series that have a weaker signal. We thus present an ensemble weighting method to mitigate these potential biases and to more accurately extract the climate signals in dendroclimatology studies. This new method has been used to develop the first annual precipitation reconstruction (previous August to current July) at the Songmingyan Mountain and to recalculate the tree-ring chronology from Shenge site in Dulan area in northeastern Tibetan Plateau (TP), a marginal area of Asian summer monsoon. The ensemble weighting method explains 31.7% of instrumental variance for the reconstructions at Songmingyan Mountain and 57.3% of the instrumental variance in the Dulan area, which are higher than those developed using traditional methods. We focus on the newly introduced reconstruction at Songmingyan Mountain, which showsextremely dry (wet) epochs from 1862-1874, 1914-1933 and 1991-1999 (1882-1905). These dry/wet epochs were also found in the marginal areas of summer monsoon and the Indian subcontinent, indicating the linkages between regional hydroclimate changes and the Indian summer monsoon. PMID:24497967

  1. Climate change and human health: Indian context.

    PubMed

    Singh, Poonam K; Dhiman, Ramesh C

    2012-06-01

    The article reviews the issue of climate change and health in the Indian context. The importance of climate change leading to estimated loss of above 2.5 million DALYs in southeast Asia, mortality due to heat waves, and the importance of air quality related respiratory diseases, disasters due to excessive floods, malnutrition due to reduction in rice, maize and sorghum crops etc. Latest work undertaken in India, vis-a-vis current scenario and need for further work has been discussed. There is felt need of further studies on assessing the impact on dengue and chikungunya as the transmission dynamics of these diseases involve water availability, storage and life style, etc. Uncertainties and knowledge gaps identified in the studies undertaken so far have also been highlighted. As regards to vector borne diseases, there is a need to concentrate in the areas which are presently free from malaria and with use of best available tools of interventions in already disease endemic areas like northeastern states, the risk of climate change impacts can be minimized. PMID:22898475

  2. Zonal temperature-anomaly maps of Indian ocean surface waters: modern and ice-age patterns.

    PubMed

    Prell, W L; Hutson, W H

    1979-10-26

    Maps of sea surface temperature anomalies in the Indian Ocean in modern and ice-age times reveal striking changes in its surface circulation. During the last glacial maximum (18,000 years before the present), the Indian Ocean had colder average zonal surface temperatures, a cooler and less extensive Agulhas Current, a distinct eastern boundary current, and decreased upwelling and a weaker southwest monsoon in its northwestern region. PMID:17809371

  3. Depositional history of Oligocene-Miocene carbonate rocks of northeastern Puerto Rico

    SciTech Connect

    Scharlach, R. )

    1990-05-01

    The apparent tectonic stability of the northern Puerto Rico platform during the late Oligocene and early Miocene allows for the depositional history of subsurface carbonate rocks of northeastern Puerto Rico to be related to major changes in eustatic sea level. During a late Oligocene north to south transgression of sea level, fluvial/deltaic to shallow marine terrigenous sediments (San Sebastian Formation) and, subsequently, open-ramp carbonates (Lares Limestone) accumulated in the central basin. Following a minor regression (third-order cycle ), a more extensive early Miocene( ) transgression resulted in deposition of deeper ramp carbonate mudstone and marl (Mudstone unit) in an apparent trough in the central basin, and open-ramp reefal carbonate (upper Lares) was deposited over a wider area of the basin. The San Sebastian Formation/Lares Limestone/Mudstone Unit sequence was most likely deposited during the second-order supercycle, TB{sub 1}. An early Miocene relative fall in sea level resulted in deposition of interfingering inner-ramp limestone and terrigenous sediments (Cibao Formation) and the development of subaerial costs, especially in the upper part of the unit. During a sea level rise, terrigenous deposition decreased and gave way to inner- and middle-ramp carbonate sediments (Los Puertos Limestone). A middle Miocene highstand in sea level brought basin-wide deposition of open-ramp carbonate sediments (Aymamon Ls). The Cibao Formation/Los Puertos Limestone/Aymamon. Limestone sequence may correspond to the second-order supercycle, TB{sub 2}. During the late middle Miocene( ), the carbonate platform was exposed and extensively karsted, possibly in an event related to the sea level drop at the end of TB{sub 2}.

  4. Native Indian Leadership.

    ERIC Educational Resources Information Center

    Jules, Felicity

    1988-01-01

    Identifies valued qualities and behaviors of Indian leaders through a literature review and unstructured interviews with three British Columbian tribal elders. Develops a model of Native leadership emphasizing connection to the people, wisdom, humility, personal integrity, service orientation, and the facilitator role. Contains 22 references. (SV)

  5. Indians of New Mexico.

    ERIC Educational Resources Information Center

    Bureau of Indian Affairs (Dept. of Interior), Washington, DC.

    The booklet gives a general introduction to American Indians in New Mexico. Covering historical background and present status, reports are given for these tribes: the 19 Pueblos (i.e., Acoma, Cochiti, Isleta, Jemez, Laguna, and Zuni), the Jicarilla and Mescalero Apaches, and the Navajos. Also included are 26 places of interest such as Acoma…

  6. American Indian Recipes.

    ERIC Educational Resources Information Center

    Gurnoe, Katherine J.; Skjervold, Christian, Ed.

    Presenting some 60 to 70 Native American recipes, this document includes a brief introduction and a suggested reading list (15 citations related to American Indian foods). The introduction identifies five regional Native American cuisines as follows: in the Southwest, peppers and beans were made into chili, soups, guacamole, and barbecue sauces by…

  7. Early Indian People.

    ERIC Educational Resources Information Center

    Doermann, Elisabeth

    1979-01-01

    Using bits and pieces of the past such as charred bits of wood from campfires, broken pieces of clay pots, stone spearpoints and arrowheads, and shell or copper ornaments, the archaeologist tries to put together the story of early Indian people in the Minnesota region. A short story, one of eight articles, re-creates the kill of an Itasca bison…

  8. Indian Reserved Water Rights.

    ERIC Educational Resources Information Center

    Bond, Frank M.

    1986-01-01

    Traces the distribution, ownership, and water usage associated with lands in the Colville Reservation in Washington State. Cites specific cases which addressed the reserved water rights doctrine. Assesses the impact of court decisions on insuring water rights for Indians living on the Colville Reservation. (ML)

  9. Indian Astronomy: History of

    NASA Astrophysics Data System (ADS)

    Mercier, R.; Murdin, P.

    2002-01-01

    From the time of A macronryabhat under dota (ca AD 500) there appeared in India a series of Sanskrit treatises on astronomy. Written always in verse, and normally accompanied by prose commentaries, these served to create an Indian tradition of mathematical astronomy which continued into the 18th century. There are as well texts from earlier centuries, grouped under the name Jyotishaveda macronn d...

  10. Indians of the Northwest.

    ERIC Educational Resources Information Center

    Bureau of Indian Affairs (Dept. of Interior), Washington, DC.

    Brief descriptions of the historical and cultural background of the Bannock, Cayuse, Coeur d'Alene, Kutenia, Kalispel, Palouse, Umatilla, Walla Walla, Yakima, Spokane, Klamath, Sanpoil, Nespelem, Colville, Quinault, Quileute, Makahs, Klallam, Lummi, Cowlit, Puyallup, Nisqually, and Nez Perce Indian tribes of the Northwestern United States are…

  11. Downriver Indians' Legends.

    ERIC Educational Resources Information Center

    Bennett, Ruth, Ed.; Exline, Jesse

    Yurok Indian legends in Yurok Unifon text include English translations of the entire texts in order to produce fluent reading for English speakers and a continuous text for Yurok readers. Although corresponding sentences are numbered, translation is not word-for-word or sentence-for-sentence. The five stories refer to a time when animals could…

  12. Eastern American Indian Communities.

    ERIC Educational Resources Information Center

    Thomas, Robert K.

    Identification of social and cultural commonalities among American Indians of the eastern U.S. reveal 4 geographical areas--(1) the eastern seaboard (the largest group in both number of distinct groups and population); (2) the inland area; (3) Louisiana (a combination of inland and seaboard characteristics); (4) the eastern Great Lakes area…

  13. Indian School Days.

    ERIC Educational Resources Information Center

    Johnston, Basil H.

    This autobiography relates the experiences of a young Ojibway boy who was taken from his family in 1939 at age 10 and placed in a Jesuit boarding school in northern Ontario, Canada. St. Peter Claver (later Garnier) or "Spanish," as the Indian school was known, was home to approximately 135 boys. Most of the students, who ranged in age from 4 to…

  14. Indians of Washington State.

    ERIC Educational Resources Information Center

    Washington Office of the State Superintendent of Public Instruction, Olympia.

    Maps, photographs, and illustrations are included in this introductory history of Indians in Washington state. The tribal groups of the area are classified by geographic and cultural region as Coastal, Puget Sound, and Plateau tribes, and the majority of the resource booklet provides information about the history and culture of each group.…

  15. Great Indian Chiefs.

    ERIC Educational Resources Information Center

    Pastron, Allen

    Brief biographies and pen and ink portraits of over 40 chiefs and other distinguised American Indians comprise this book. Each page contains a full page portrait and a biography that notes tribal affiliation, important dates, geographical location, major accomplishments, and dealings with other tribes, white settlers, and the United States or…

  16. Indians of Maine.

    ERIC Educational Resources Information Center

    Maine State Dept. of Health and Welfare, Augusta.

    The relationships between the Penobscot and Passamaquoddy Indian Tribes and the State of Maine began in the 1820's. Treaties have left the Penobscot tribe with ownership of 146 islands in the Penobscot River while the Passamaquoddy tribe lives on land owned by the State. Both tribes presently have trust funds derived from the sale of land, and use…

  17. Indians of Arizona.

    ERIC Educational Resources Information Center

    Bureau of Indian Affairs (Dept. of Interior), Washington, DC.

    Brief descriptions of the historical and cultural background of the Navajo, Apache, Hopi, Pima, Papago, Yuma, Maricopa, Mohave, Cocopah, Havasupai, Hualapai, Yavapai, and Paiute Indian tribes of Arizona are presented. Further information is given concerning the educational, housing, employment, and economic development taking place on the…

  18. American Indian Authors.

    ERIC Educational Resources Information Center

    Momaday, Natachee Scott

    Twenty-six selections by 15 contemporary American Indian authors are given in this book. The selections--legends, ceremonial chants and prayers, poems, and stories--are accompanied by topics for discussion. Some of the selections deal with the supernatural, and some tell an actual story about the author. Pictures and short biographies of each…

  19. Indians of North Carolina.

    ERIC Educational Resources Information Center

    Bureau of Indian Affairs (Dept. of Interior), Washington, DC.

    Published by the U.S. Department of the Interior, this brief booklet on the historical development of the Cherokee Nation emphasizes the Tribe's relationship with the Bureau of Indian Affairs and its improved economy. Citing tourism as the major tribal industry, tribal enterprises are named and described (a 61 unit motor court in existence since…

  20. The Urban Indian.

    ERIC Educational Resources Information Center

    Hanson, Winona DuBray

    The document presents six articles that provide a glimpse of the uniqueness of American Indian cultural conflict, focusing on aspects of the culture which warrant special attention. Since there are over 100 tribes, an effort was made to enumerate commonalities amongst the tribal cultures in looking at issues raised in the urban areas throughout…