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Sample records for prudhoe bay region

  1. Genetic relationships of grizzly bears (Ursus arctos) in the Prudhoe Bay region of Alaska: inference from microsatellite DNA, mitochondrial DNA, and field observations.

    Science.gov (United States)

    Cronin, M; Shideler, R; Hechtel, J; Strobeck, C; Paetkau, D

    1999-01-01

    Grizzly bears are abundant in the region of the Prudhoe Bay oil fields in northern Alaska. We used field observations and molecular genetic data to identify parent-offspring and sibling relationships among bears in this region. We determined genotypes at 14 microsatellite DNA loci and the cytochrome b gene of mitochondrial DNA (mtDNA) for 36 bears. We identified 17 possible mother-offspring pairs and 8 possible father-offspring pairs. This includes verification of the relationships of 14 mother-offspring pairs identified from field observations. Three additional mother-offspring pairs and all eight father-offspring pairs were determined from genetic and age data. Relatedness coefficients based on numbers of shared alleles between individuals were as expected: approximately 0.50 for parent-offspring and sibling pairs and approximately 0.75 for a father-offspring pair resulting from a father-daughter mating. The level of genetic variation (mean number of alleles per locus = 6.6, mean heterozygosity = 70%) and allele frequencies in grizzly bears in the Prudhoe Bay region are similar to those in other parts of the species' range.

  2. Arctic cisco stable isotope data, Prudhoe Bay, August 2009

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set documents the carbon and nitrogen stable isotope ratios of age-0 Arctic cisco (Coregonus autumnalis) captured in Prudhoe Bay, Alaska in August 2009....

  3. Chemical Characterization of Atmospheric Particulate Matter from Prudhoe Bay, Alaska

    Science.gov (United States)

    Gunsch, M.; Kirpes, R.; Moffett, C. E.; Sheesley, R. J.; Pratt, K.

    2016-12-01

    Climate change is impacting the Arctic, leading to increasing temperatures and decreasing summer sea ice coverage which has allowed for increased oil and gas extraction activities. Prudhoe Bay is currently the second highest source of particulate matter from oil and gas extraction in the Arctic, and 3rd largest oil field in the United States. With drilling operations expected to increase due to the reduced sea ice coverage, these emissions, specifically contributions from black carbon and organic carbon, are expected to continue to increase over the coming decades. Given the complexity and evolving nature of atmospheric particles, as well as the logistical challenges associated with Arctic measurements, many uncertainties remain in our understanding of the impacts of increasing emissions in the Arctic. To investigate the size and chemistry of individual particles emitted from activities within the Prudhoe Bay oil fields in real-time, an aerosol time-of-flight mass spectrometer (ATOFMS) was deployed 300 km northwest of Prudhoe Bay to Barrow, AK during August-September 2015 as well as inside the Prudhoe Bay oil fields at Oliktok Point, AK during August-September 2016. During the 2015 measurements, particle number concentrations increased 10 times when under the influence of Prudhoe Bay, primarily from sub-50 nm particles attributed to transported combustion emissions. ATOFMS also identified increased number fractions of soot and organic carbon-sulfate particles (0.2 - 1.5 μm in diameter) when comparing Prudhoe Bay influential periods to Arctic Ocean influential periods. During 2016 measurements, parallel size-resolved number concentration measurements allowed for near-source quantification of number and mass concentrations of particles from the various sources of combustion within the oil fields, including residual fuel, diesel fuel and biomass burning. These measurements represent the first single particle chemical characterization of oil and gas extraction

  4. Thermal regime of permafrost at Prudhoe Bay, Alaska

    Science.gov (United States)

    Lachenbruch, A.H.; Sass, J.H.; Marshall, B.V.; Moses, T.H.

    1982-01-01

    Temperature measurements through permafrost in the oil field at Prudhoe Bay, Alaska, combined with laboratory measurements of the thermal conductivity of drill cuttings permit an evaluation of in situ thermal properties and an understanding of the general factors that control the geothermal regime. A sharp contrast in temperature gradient at ~600 m represents a contrast in thermal conductivity caused by the downward change from interstitial ice to interstitial water at the base of permafrost under near steady-state conditions. Interpretation of the gradient contrast in terms of a simple model for the conductivity of an aggregate yields the mean ice content and thermal conductivities for the frozen and thawed sections (8.1 and 4.7 mcal/cm sec ?C, respectively). These results yield a heat flow of ~1.3 HFU which is similar to other values on the Alaskan Arctic Coast; the anomalously deep permafrost is a result of the anomalously high conductivity of the siliceous ice-rich sediments. Curvature in the upper 160 m of the temperature profiles represents a warming of ~1.8?C of the mean surface temperature, and a net accumulation of 5-6 kcal/cm 2 by the solid earth surface during the last 100 years or so. Rising sea level and thawing sea cliffs probably caused the shoreline to advance tens of kilometers in the last 20,000 years, inundating a portion of the continental shelf that is presently the target of intensive oil exploration. A simple conduction model suggests that this recently inundated region is underlain by near-melting ice-rich permafrost to depths of 300-500 m; its presence is important to seismic interpretations in oil exploration and to engineering considerations in oil production. With confirmation of the permafrost configuration by offshore drilling, heat-conduction models can yield reliable new information on the chronology of arctic shorelines.

  5. Pre-ABoVE: Geobotanical and Impact Map Collection for Prudhoe Bay Oilfield, Alaska

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set provides a collection of maps of geoecological characteristics of areas within the Beechey Point quadrangle near Prudhoe Bay on the North slope of...

  6. Summer bird use of a barrier island near Prudhoe Bay, Alaska

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The number and distribution of birds near a barrier island west of Prudhoe Bay, Alaska, were recorded during the summer of 1972. Eiders fed and rested in the open...

  7. Reservoir description of Endicott Field, Prudhoe Bay, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Behrman, P.G.; Woidneck, R.K.; Soule, C.H.; Wu, J.L.

    1985-04-01

    Located about 2 mi offshore and several miles east of Prudhoe Bay, the Endicott field contains about 1.4 billion reservoir bbl of oil and 0.5 billion reservoir bbl of gas. Hydrocarbons occur within Mississippian fluvial sandstones of the Kekiktuk formation, which unconformably overlies the Neruokpuk Formation and grades upward into the Kayak and Itkilyariak formations. Stratigraphy is subdivided into three lithofacies that, from the base upward, reflect deposition in a swamp/lacustrine/flood plain environment (zone I), a braided stream system (zone 2), and a meandering stream system (zone 3). Sediment dispersal was from a northerly source. Endicott field structure defines a southwesterly plunging antiform that is bounded to the north, northeast, and southwest by major normal faults and is truncated to the northeast by the Lower Cretaceous Unconformity (LCU). Shales overlying the LCU and shales of the Kayak and Itkilyariak formations from the reservoir cap. Reservoir properties with the hydrocarbon column vary by zone with zones 3 and 2 typified by an average net/gross-porosity-water saturation-permeability of 37%-18%-22%-500 md and 88%-22%-13%-1100 md, respectively. In contrast, zone 1 quality is very poor. Reservoir sands are compositionally very mature and exhibit an enhanced pore network. Diagenetic minerals include quartz along with lesser kaolinite and carbonate. Gas is present from about 9500 ft (2850 m) to 9855 ft (2958 m), oil is down to 10,180-10,200 ft (3054-3060 m), and tar accumulations are down to 10,400 ft (3120 m) subsea. Average oil gravity is 23/sup 0/ API. Geochemical data indicate that the tar accumulations originated through a physical deasphaltine process. Cenozoic imbibition resulted in water overriding tar.

  8. Contributions of transported Prudhoe Bay oil field emissions to the aerosol population in Utqiagvik, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Gunsch, Matthew J.; Kirpes, Rachel M.; Kolesar, Katheryn R.; Barrett, Tate E.; China, Swarup; Sheesley, Rebecca J.; Laskin, Alexander; Wiedensohler, Alfred; Tuch, Thomas; Pratt, Kerri A.

    2017-01-01

    Loss of sea ice is opening the Arctic to increasing development involving oil and gas extraction and shipping. Given the significant impacts of absorbing aerosol and secondary aerosol precursors emitted within the rapidly warming Arctic region, it is necessary to characterize local anthropogenic aerosol sources and compare to natural conditions. From August to September 2015 in Utqiagvik (Barrow), AK, the chemical composition of individual atmospheric particles was measured by computer-controlled scanning electron microscopy with energy-dispersive X-ray spectroscopy (0.13–4 µm projected area diameter) and real-time single-particle mass spectrometry (0.2–1.5 µm vacuum aerodynamic diameter). During periods influenced by the Arctic Ocean (70 % of the study), our results show that fresh sea spray aerosol contributed ~20 %, by number, of particles between 0.13 and 0.4 µm, 40–70 % between 0.4 and 1 µm, and 80–100 % between 1 and 4 µm particles. In contrast, for periods influenced by emissions from Prudhoe Bay (10 % of the study), the third largest oil field in North America, there was a strong influence from submicron (0.13–1 µm) combustion-derived particles (20–50 % organic carbon, by number; 5–10% soot by number). While sea spray aerosol still comprised a large fraction of particles (90 % by number from 1 to 4 µm) detected under Prudhoe Bay influence, these particles were internally mixed with sulfate and nitrate indicative of aging processes during transport. In addition, the overall mode of the particle size number distribution shifted from 76 nm during Arctic Ocean influence to 27 nm during Prudhoe Bay influence, with particle concentrations increasing from 130 to 920 cm-3 due to transported particle emissions from the oil fields. The increased contributions of carbonaceous combustion products and partially aged sea spray aerosol should be considered in future Arctic atmospheric composition and climate simulations.

  9. Contributions of transported Prudhoe Bay oil field emissions to the aerosol population in Utqiaġvik, Alaska

    Science.gov (United States)

    Gunsch, Matthew J.; Kirpes, Rachel M.; Kolesar, Katheryn R.; Barrett, Tate E.; China, Swarup; Sheesley, Rebecca J.; Laskin, Alexander; Wiedensohler, Alfred; Tuch, Thomas; Pratt, Kerri A.

    2017-09-01

    Loss of sea ice is opening the Arctic to increasing development involving oil and gas extraction and shipping. Given the significant impacts of absorbing aerosol and secondary aerosol precursors emitted within the rapidly warming Arctic region, it is necessary to characterize local anthropogenic aerosol sources and compare to natural conditions. From August to September 2015 in Utqiaġvik (Barrow), AK, the chemical composition of individual atmospheric particles was measured by computer-controlled scanning electron microscopy with energy-dispersive X-ray spectroscopy (0.13-4 µm projected area diameter) and real-time single-particle mass spectrometry (0.2-1.5 µm vacuum aerodynamic diameter). During periods influenced by the Arctic Ocean (70 % of the study), our results show that fresh sea spray aerosol contributed ˜ 20 %, by number, of particles between 0.13 and 0.4 µm, 40-70 % between 0.4 and 1 µm, and 80-100 % between 1 and 4 µm particles. In contrast, for periods influenced by emissions from Prudhoe Bay (10 % of the study), the third largest oil field in North America, there was a strong influence from submicron (0.13-1 µm) combustion-derived particles (20-50 % organic carbon, by number; 5-10 % soot by number). While sea spray aerosol still comprised a large fraction of particles (90 % by number from 1 to 4 µm) detected under Prudhoe Bay influence, these particles were internally mixed with sulfate and nitrate indicative of aging processes during transport. In addition, the overall mode of the particle size number distribution shifted from 76 nm during Arctic Ocean influence to 27 nm during Prudhoe Bay influence, with particle concentrations increasing from 130 to 920 cm-3 due to transported particle emissions from the oil fields. The increased contributions of carbonaceous combustion products and partially aged sea spray aerosol should be considered in future Arctic atmospheric composition and climate simulations.

  10. Abundance and movements of caribou in the oilfield complex near Prudhoe Bay, Alaska

    Directory of Open Access Journals (Sweden)

    R.D. Cameron

    1995-12-01

    Full Text Available We examined the distribution and movements of 141 radiocollared female caribou (Rangifer tarandus granti of the Central Arctic Herd during summer, 1980-1993. Numbers of caribou locations within each of 5 quadrats along the arctic coast were totalled separately for days during which insects were active and inactive, and numbers of east-west and west-east crossings of each quadrat mid-line were determined from sequential observations. Both abundance and lateral movements of radiocollared females in the quadrat encompassing the intensively-developed Prudhoe Bay oilfield complex were significantly lower than in other quadrats (P < 0.001 and P < 0.00001, respectively. Avoidance of, and fewer movements within, the complex by female caribou are ostensibly in response to the dense network of production and support facilities, roads, above-ground pipelines, and the associated vehicular and human activity. Impaired access to this area constitutes a functional loss of habitat.

  11. Cumulative effects of climate change and ice-wedge degradation, Prudhoe Bay oilfield Alaska

    Science.gov (United States)

    Walker, D. A.; Kanevskiy, M. Z.; Shur, Y.; Raynolds, M. K.; Buchhorn, M.

    2016-12-01

    Development of Arctic oil & gas resources requires extensive networks of roads, pipelines and other forms of infrastructure. The Prudhoe Bay Oilfield is the largest Arctic oilfield in North America with a long, well-documented history. In a previous publication we analyzed the historical record of high-resolution aerial photos to document the long-term changes to infrastructure extent (1949-2010) for the entire oilfield, and an integrated-geoecological-historical-change-mapping (IGHCM) approach to document terrain changes within 22-km2 areas of the oilfield. We reported the recent widespread expansion of thermokarst, starting in about 1989. Here we examine the annual air-photo record to better pinpoint the years of major change. We also conducted detailed field studies of roadside changes using topographic surveys and soil, vegetation and ice-wedge coring studies. Both sites exhibit extensive ice-wedge degradation that is caused by a combination of a long-term warming trend a series of exceptionally warm summers, and infrastructure-related factors that melted the tops of ice wedges. Near-road thermokarst is enhanced by warmer soils associated with road dust, roadside flooding, near-road pipelines, communication cables, and altered snow regimes. These strongly affect roadside ecosystems and the infrastructure itself. Changes to ecosystems include altered hydrology with the drying of polygon centers and the formation of well-developed high-centered polygons occurs in some areas. Other areas develop extensive flooding and erosion of ice-wedge troughs. An unexpected result of flooding is the stabilization of ice-wedge degradation in some areas because the increased productivity of sedges in the flooded areas is producing large amounts of organic material that protects the tops of ice wedges from further degradation. The large increases in productivity in roadside areas also attract large flocks of waterfowl. Changes to the soils with the addition of thick layers of

  12. Vegetation and Environmental Gradients of the Prudhoe Bay Region, Alaska,

    Science.gov (United States)

    1985-09-01

    Numerous taxonomists generously helped with the plant identifications. Dr. David Murray, University of Alaska Museum, and Dr. William Weber...Britton reviewed this work, and his comments are much appreciated. David Cate, CRREL, made numerous very helpful suggestions and has greatly helped the...111,, NOIA MNSCTAI 13.03 03 03 03 03 03 03 03 03 03 03 03 031 03 03 91 I1i IfIN LITRCOT O 03 0O) O ) 3 0 0 ) O 03 0 ( 3 0 ( .5 0( 1 L IV[ P’WORTS 1 7 3

  13. Molecular and isotopic analyses of the hydrocarbon gases within gas hydrate-bearing rock units of the Prudhoe Bay-Kuparuk River area in northern Alaska

    Science.gov (United States)

    Valin, Zenon C.; Collett, Timothy S.

    1992-01-01

    Gas hydrates, which are crystalline substances of water molecules that encase gas molecules, have the potential for being a significant source of natural gas. World-wide estimates for the amount of gas contained in hydrates range from 1.1 x 105 to 2.7 x 108 trillion cubic feet. Gas hydrates exist in many Arctic regions, including the North Slope of Alaska. The two primary objectives of the U.S. Geological Survey Gas Hydrate Research Project are (1) to map the distribution of in-situ gas hydrates on the North Slope of Alaska, and (2) to evaluate the geologic parameters that control the distribution of these gas hydrates. To aid in this study, British Petroleum Exploration, ARCO Alaska, Exxon Company USA, and the Continental Oil Company allowed the U.S. Geological Survey to collect geochemical samples from drilling North Slope production wells. Molecular analysis of gaseous drill cutting and free-flowing gas samples from 10 production wells drilled in the Prudhoe Bay, Kuparuk River, and Milne Point oil fields indicates that methane is the primary hydrocarbon gas in the gas hydrate-bearing stratigraphic units. Isotopic data for several of these rock units indicate that the methane within the inferred gas hydrate occurences originated from both microbial and thermogenic processes.

  14. Cumulative geoecological effects of 62 years of infrastructure and climate change in ice-rich permafrost landscapes, Prudhoe Bay Oilfield, Alaska.

    Science.gov (United States)

    Raynolds, Martha K; Walker, Donald A; Ambrosius, Kenneth J; Brown, Jerry; Everett, Kaye R; Kanevskiy, Mikhail; Kofinas, Gary P; Romanovsky, Vladimir E; Shur, Yuri; Webber, Patrick J

    2014-04-01

    Many areas of the Arctic are simultaneously affected by rapid climate change and rapid industrial development. These areas are likely to increase in number and size as sea ice melts and abundant Arctic natural resources become more accessible. Documenting the changes that have already occurred is essential to inform management approaches to minimize the impacts of future activities. Here, we determine the cumulative geoecological effects of 62 years (1949-2011) of infrastructure- and climate-related changes in the Prudhoe Bay Oilfield, the oldest and most extensive industrial complex in the Arctic, and an area with extensive ice-rich permafrost that is extraordinarily sensitive to climate change. We demonstrate that thermokarst has recently affected broad areas of the entire region, and that a sudden increase in the area affected began shortly after 1990 corresponding to a rapid rise in regional summer air temperatures and related permafrost temperatures. We also present a conceptual model that describes how infrastructure-related factors, including road dust and roadside flooding are contributing to more extensive thermokarst in areas adjacent to roads and gravel pads. We mapped the historical infrastructure changes for the Alaska North Slope oilfields for 10 dates from the initial oil discovery in 1968-2011. By 2010, over 34% of the intensively mapped area was affected by oil development. In addition, between 1990 and 2001, coincident with strong atmospheric warming during the 1990s, 19% of the remaining natural landscapes (excluding areas covered by infrastructure, lakes and river floodplains) exhibited expansion of thermokarst features resulting in more abundant small ponds, greater microrelief, more active lakeshore erosion and increased landscape and habitat heterogeneity. This transition to a new geoecological regime will have impacts to wildlife habitat, local residents and industry. © 2013 John Wiley & Sons Ltd.

  15. Resource Characterization and Quantification of Natural Gas-Hydrate and Associated Free-Gas Accumulations in the Prudhoe Bay - Kuparuk River Area on the North Slope of Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Shirish Patil; Abhijit Dandekar

    2008-12-31

    Natural gas hydrates have long been considered a nuisance by the petroleum industry. Hydrates have been hazards to drilling crews, with blowouts a common occurrence if not properly accounted for in drilling plans. In gas pipelines, hydrates have formed plugs if gas was not properly dehydrated. Removing these plugs has been an expensive and time-consuming process. Recently, however, due to the geologic evidence indicating that in situ hydrates could potentially be a vast energy resource of the future, research efforts have been undertaken to explore how natural gas from hydrates might be produced. This study investigates the relative permeability of methane and brine in hydrate-bearing Alaska North Slope core samples. In February 2007, core samples were taken from the Mt. Elbert site situated between the Prudhoe Bay and Kuparuk oil fields on the Alaska North Slope. Core plugs from those core samples have been used as a platform to form hydrates and perform unsteady-steady-state displacement relative permeability experiments. The absolute permeability of Mt. Elbert core samples determined by Omni Labs was also validated as part of this study. Data taken with experimental apparatuses at the University of Alaska Fairbanks, ConocoPhillips laboratories at the Bartlesville Technology Center, and at the Arctic Slope Regional Corporation's facilities in Anchorage, Alaska, provided the basis for this study. This study finds that many difficulties inhibit the ability to obtain relative permeability data in porous media-containing hydrates. Difficulties include handling unconsolidated cores during initial core preparation work, forming hydrates in the core in such a way that promotes flow of both brine and methane, and obtaining simultaneous two-phase flow of brine and methane necessary to quantify relative permeability using unsteady-steady-state displacement methods.

  16. RESOURCE CHARACTERIZATION AND QUANTIFICATION OF NATURAL GAS-HYDRATE AND ASSOCIATED FREE-GAS ACCUMULATIONS IN THE PRUDHOE BAY - KUPARUK RIVER AREA ON THE NORTH SLOPE OF ALASKA

    Energy Technology Data Exchange (ETDEWEB)

    Robert Hunter; Shirish Patil; Robert Casavant; Tim Collett

    2003-06-02

    Interim results are presented from the project designed to characterize, quantify, and determine the commercial feasibility of Alaska North Slope (ANS) gas-hydrate and associated free-gas resources in the Prudhoe Bay Unit (PBU), Kuparuk River Unit (KRU), and Milne Point Unit (MPU) areas. This collaborative research will provide practical input to reservoir and economic models, determine the technical feasibility of gas hydrate production, and influence future exploration and field extension of this potential ANS resource. The large magnitude of unconventional in-place gas (40-100 TCF) and conventional ANS gas commercialization evaluation creates industry-DOE alignment to assess this potential resource. This region uniquely combines known gas hydrate presence and existing production infrastructure. Many technical, economical, environmental, and safety issues require resolution before enabling gas hydrate commercial production. Gas hydrate energy resource potential has been studied for nearly three decades. However, this knowledge has not been applied to practical ANS gas hydrate resource development. ANS gas hydrate and associated free gas reservoirs are being studied to determine reservoir extent, stratigraphy, structure, continuity, quality, variability, and geophysical and petrophysical property distribution. Phase 1 will characterize reservoirs, lead to recoverable reserve and commercial potential estimates, and define procedures for gas hydrate drilling, data acquisition, completion, and production. Phases 2 and 3 will integrate well, core, log, and long-term production test data from additional wells, if justified by results from prior phases. The project could lead to future ANS gas hydrate pilot development. This project will help solve technical and economic issues to enable government and industry to make informed decisions regarding future commercialization of unconventional gas-hydrate resources.

  17. k179ar.m77t - MGD77 data file for Geophysical data from field activity K-1-79-AR in Prudhoe Bay, Alaska, Arctic Ocean from 07/23/1979 to 08/20/1979

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Single-beam bathymetry data along with DGPS navigation data was collected as part of field activity K-1-79-AR in Prudhoe Bay, Alaska, Arctic Ocean from 07/23/1979 to...

  18. SOHIO (Standard Oil Co. , Ohio) to sell Prudhoe gas to Northern Natural Gas Co

    Energy Technology Data Exchange (ETDEWEB)

    1979-08-20

    Sohio has agreed to sell Vertical Bar3: 2 trillion cu ft of its Prudhoe Bay gas to Northern Natural Gas Co. for delivery at a rate of 170 million cu ft/day when the proposed Alaska Highway gas pipeline is completed. With the exception of approx. 4 trillion cu ft of Sohio's reserves committed to Columbia Gas System Inc., the agreement accounts for the sale of all the 26.5-27 trillion cu ft of Prudhoe Bay reserves. The contract, which is subject to approval of the U.S. Federal Energy Regulatory Commission, allows Alaska to take its one-eighth royalty share of the gas in kind or cash. Columbia Gas is the only firm planning to purchase Prudhoe Bay gas that is not participating as an equity owner in the pipeline project. According to a Columbia spokesman, it is still uncertain whether the proposed gas pipeline will be built; and the fact that Columbia has not yet signed a final agreement with Sohio does not indicate any decreasing interest in Prudhoe Bay gas.

  19. Hydrogeomorphic Regions in the Chesapeake Bay Watershed.

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Generalized lithology (rock type) and physiography based on geologic formations were used to characterize hydrgeomorphic regions (HGMR) within the Chesapeake Bay...

  20. Crustal structure of Bristol Bay Region, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, A.K.; McLean, H.; Marlow, M.S.

    1985-04-01

    Bristol Bay lies along the northern side of the Alaska Peninsula and extends nearly 600 km southwest from the Nushagak lowlands on the Alaska mainland to near Unimak Island. The bay is underlain by a sediment-filled crustal downwarp known as the north Aleutian basin (formerly Bristol basin) that dips southeast toward the Alaska Peninsula and is filled with more than 6 km of strata, dominantly of Cenozoic age. The thickest parts of the basin lie just north of the Alaska Peninsula and, near Port Mollar, are in fault contact with older Mesozoic sedimentary rocks. These Mesozoic rocks form the southern structural boundary of the basin and extend as an accurate belt from at least Cook Inlet to Zhemchug Canyon (central Beringian margin). Offshore multichannel seismic-reflection, sonobuoy seismic-refraction, gravity, and magnetic data collected by the USGS in 1976 and 1982 indicate that the bedrock beneath the central and northern parts of the basin comprises layered, high-velocity, and highly magnetic rocks that are locally deformed. The deep bedrock horizons may be Mesozoic(.) sedimentary units that are underlain by igneous or metamorphic rocks and may correlate with similar rocks of mainland western Alaska and the Alaska Peninsula. Regional structural and geophysical trends for these deep horizons change from northeast-southwest to northwest-southeast beneath the inner Bering shelf and may indicate a major crustal suture along the northern basin edge.

  1. The ichthyoplankton assemblage of the Algoa Bay nearshore region ...

    African Journals Online (AJOL)

    The ichthyoplankton assemblage of the Algoa Bay nearshore region in relation to coastal zone utilization by juvenile fish. ... The paucity of larvae of coastal species with pelagic eggs is highlighted and, with reference to the findings of other workers and local oceanographic conditions, a possible spawning strategy is ...

  2. Modeling the hydrodynamic responses to land reclamation in different regions of a semi-enclosed bay

    Science.gov (United States)

    Yang, Y.; Chui, T. F. M.

    2016-12-01

    Water area in bays has been reclaimed to meet the increasing land demand for development. Numbers of studies have examined the hydrodynamic impacts induced by land reclamations in semi-enclosed bays such as San Francisco Bay in the U.S., Tokyo Bay in Japan, and Jiaozhou Bay in China. However, they have not compared the impacts of land reclamations taken place in different regions. The Deep Bay in China was selected as a case study to evaluate and compare the hydrodynamic responses to land reclamations that narrows the bay mouth and that causes water surface loss inside of the bay. A numerical model was employed to simulate the hydrodynamics throughout the bay and to examine the differences in impacts through scenario experiments. The model was validated using the observations of water elevation, currents, and salinity. To indicate the changes in hydrodynamics, tidal prism, current field, tidal energy flux, and water age were computed. Simulation results show that narrowing the bay mouth length by 30% with ??% loss of its original water surface area would increase the total energy flux entering the bay by 26 %, while 14% loss of its original water surface area in middle bay would decrease the total energy entering the bay by 23%. The two regions of reclamations have both resulted in substantial but different changes in current field, the spatial distribution of tidal energy flux and water age. For example, the reclamation at bay mouth has increased the current velocity and tidal energy flux at the bay mouth while that inside of the bay has streamlined the current field and increased the velocity in the inner bay. The water age throughout the bay has been reduced by 5.1% and 13.7% respectively in the two scenarios, increasing the water exchange ability of the bay with the adjacent sea. This study is beneficial to other semi-enclosed bays considering land reclamations, facilitating quick and preliminary estimations of hydrodynamic impacts for planning and management.

  3. An Evaluation of Sea Ice Deformation and Its Spatial Characteristics from the Regional Arctic System Model

    Science.gov (United States)

    2012-12-01

    ANWR, was not included in the act. Upon discovery of oil in Prudhoe Bay in 1968, the U.S. government began plans to build an oil pipeline from Prudhoe...J.A. Richter-Menge, 2010: Influences of the ocean surface mixed layer and thermohaline stratification on Arctic sea ice in the central Canada Basin

  4. Regional Sediment Management (RSM) Strategy for Mobile Bay, Alabama

    Science.gov (United States)

    2015-04-01

    used to model and evaluate the behavior of sediment placed within Mobile Bay. SEDIMENT TRANSPORT WITHIN MOBILE BAY: A sediment budget for Mobile...benthic invertebrates in the pit basin while not adversely impacting the pit with regards to fish utilization or recreational fishing. 2) A second...were seasonally occupied by fishery resource assemblages typical of greater Mobile Bay. Species composition included several taxa that exemplify

  5. San Francisco Bay Water Quality Improvement Fund Points, SF Bay CA, 2015, US EPA Region 9

    Data.gov (United States)

    U.S. Environmental Protection Agency — The San Francisco Bay Water Quality Improvement Fund is a competitive grant program that is helping implement TMDLs to improve water quality, protect wetlands, and...

  6. Regional Air Toxics Modeling in California's San Francisco Bay Area

    Science.gov (United States)

    Martien, P. T.; Tanrikulu, S.; Tran, C.; Fairley, D.; Jia, Y.; Fanai, A.; Reid, S.; Yarwood, G.; Emery, C.

    2011-12-01

    Regional toxics modeling conducted for California's San Francisco Bay Area (SFBA) estimated potential cancer risk from diesel particulate matter (DPM) and four key reactive toxic gaseous pollutants (1,3-butadiene, benzene, formaldehyde, and acetaldehyde). Concentrations of other non-cancerous gaseous toxic air contaminants, including acrolein, were also generated. In this study, meteorological fields generated from July and December periods in 2000 and emissions from 2005 provided inputs to a three-dimensional air quality model at high spatial resolution (1x1 km^2 grid), from which a baseline set of annual risk values was estimated. Simulated risk maps show highest annual average DPM concentrations and cancer risks were located near and downwind of major freeways and near the Port of Oakland, a major container port in the area. Population weighted risks, using 2000 census data, were found to be highest in highly urbanized areas adjacent to significant DPM sources. For summer, the ratio of mean measured elemental carbon to mean modeled DPM was 0.78, conforming roughly to expectations. But for winter the ratio is 1.13, suggesting other sources of elemental carbon, such as wood smoke, are important. Simulated annual estimates for benzene and 1-3, butadiene compared well to measured annual estimates. Simulated acrolein and formaldehyde significantly under-predicted observed values. Simulations repeated using projected 2015 toxic emissions predicted that potential cancer risk dropped significantly in all areas throughout the SFBA. Emissions estimates for 2015 included the State of California's recently adopted on-road truck rule. Emission estimates of DPM are projected to drop about 70% between 2005 and 2015 in the SFBA, with a commensurate reduction in potential cancer risks. However, due to projected shifts in population during this period, with urban densification close to DPM sources outpacing emission reductions, there are some areas where population-weighted risks

  7. Foraminiferal abundance in the modified marine environment of Cola Bay region of Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Setty, M.G.A.P.; Narayanan, V.

    perforate foraminifera are found to be very abundant over all other types in the living populations. In the Cola Bay region of Goa, where the marine environment is affected by the industrial effluents, the foraminiferal distribution shows that @i...

  8. Beneficial Uses of Dredged Material Case Study: San Francisco Bay Region

    Science.gov (United States)

    A major interagency, regional planning effort led to the development of the Long-Term Management Strategy and other planning programs in the San Francisco Bay area. These programs incorporate beneficial uses of dredged material into local projects.

  9. Vapor Intrusion Facility Points, South Bay CA, 2014, US EPA Region 9

    Data.gov (United States)

    U.S. Environmental Protection Agency — POINT locations for the South Bay Vapor Instrusion Sites were derived from the NPL data for Region 9. One site, Philips Semiconductor, was extracted from the...

  10. Cenozoic stratigraphy and structure of the Chesapeake Bay region

    Science.gov (United States)

    Powars, David S.; Edwards, Lucy E.; Kidwell, Susan M.; Schindler, J. Stephen

    2015-01-01

    The Salisbury embayment is a broad tectonic downwarp that is filled by generally seaward-thickening, wedge-shaped deposits of the central Atlantic Coastal Plain. Our two-day field trip will take us to the western side of this embayment from the Fall Zone in Washington, D.C., to some of the bluffs along Aquia Creek and the Potomac River in Virginia, and then to the Calvert Cliffs on the western shore of the Chesapeake Bay. We will see fluvial-deltaic Cretaceous deposits of the Potomac Formation. We will then focus on Cenozoic marine deposits. Transgressive and highstand deposits are stacked upon each other with unconformities separating them; rarely are regressive or lowstand deposits preserved. The Paleocene and Eocene shallow shelf deposits consist of glauconitic, silty sands that contain varying amounts of marine shells. The Miocene shallow shelf deposits consist of diatomaceous silts and silty and shelly sands. The lithology, thickness, dip, preservation, and distribution of the succession of coastal plain sediments that were deposited in our field-trip area are, to a great extent, structurally controlled. Surficial and subsurface mapping using numerous continuous cores, auger holes, water-well data, and seismic surveys has documented some folds and numerous high-angle reverse and normal faults that offset Cretaceous and Cenozoic deposits. Many of these structures are rooted in early Mesozoic and/or Paleozoic NE-trending regional tectonic fault systems that underlie the Atlantic Coastal Plain. On Day 1, we will focus on two fault systems (stops 1–2; Stafford fault system and the Skinkers Neck–Brandywine fault system and their constituent fault zones and faults). We will then see (stops 3–5) a few of the remaining exposures of largely unlithified marine Paleocene and Eocene strata along the Virginia side of the Potomac River including the Paleocene-Eocene Thermal Maximum boundary clay. These exposures are capped by fluvial-estuarine Pleistocene terrace

  11. Assessing Sustainable Developments in a Coastal Region: the Garolim Bay in the West Coast of Korea

    Science.gov (United States)

    Park, M. J.

    2016-12-01

    The Garolim Bay is a semi-enclosed bay located in the west coast of Korea and has a spring tidal range over 6 m. It is well known for vast tidal flats and healthy ecosystems that supports high productive and diverse marine lives. Due to its large tidal range it was considered favorable site for the construction of tidal power plant and went through controversies over decades. Local fishermen depending on their livelihood over generations strongly opposed the construction, so did the most environmental groups. They argued that construction of the tidal barrage at the entrance of the bay will reduce the tidal range resulting in increase of mud content of bottom sediments and disruption of marine lives. On the other hand, the power generation industry and some local residents supported the construction arguing that the tidal power is renewable energy and contributes to reduction of CO2 emission along with economic benefits from tourists' sightseeing of the tidal power plant. The application of the tidal power plant construction at the Garolim Bay was not approved by the Korean government due to the concerns of environmental impacts on the marine lives of the Garolim Bay region. This study briefly reviews developments associated with the tidal power plant construction in the Garolim Bay and considers how to approach the assessment of the sustainable development of the coastal region of the Garolim Bay in accordance with UN Sustainable Development Goals (SDG) 2030 with appropriate goals, targets and monitoring indicators. It will be of keen interests to policy makers of central and local governments as well as local residents to monitor and find out the benefits pursuing SDG in the Garolim Bay where conflicts of interests among stakeholders persisted, and may exemplify the case for other regions of similar situations.

  12. THE BAFFIN BAY REGION DURING THE LAST INTERGLACIATION: EVIDENCE FROM NORTHWEST GREENLAND

    DEFF Research Database (Denmark)

    Funder, Svend Visby

    1989-01-01

    Coastal sections in the Thule area, northwest Greenland, provide a recordof last interglacial glacial and oceanographic events on the northern perimeter of Baffin Bay. The record is dated by a combination of thermoluminescence and 14C dating; local and regional correlation is provided by amino acid...... that in this large region there was a causal relationship between oceanographic change and glaciation....

  13. Land subsidence and relative sea-level rise in the southern Chesapeake Bay region

    Science.gov (United States)

    Eggleston, Jack; Pope, Jason

    2013-01-01

    The southern Chesapeake Bay region is experiencing land subsidence and rising water levels due to global sea-level rise; land subsidence and rising water levels combine to cause relative sea-level rise. Land subsidence has been observed since the 1940s in the southern Chesapeake Bay region at rates of 1.1 to 4.8 millimeters per year (mm/yr), and subsidence continues today. This land subsidence helps explain why the region has the highest rates of sea-level rise on the Atlantic Coast of the United States. Data indicate that land subsidence has been responsible for more than half the relative sea-level rise measured in the region. Land subsidence increases the risk of flooding in low-lying areas, which in turn has important economic, environmental, and human health consequences for the heavily populated and ecologically important southern Chesapeake Bay region. The aquifer system in the region has been compacted by extensive groundwater pumping in the region at rates of 1.5- to 3.7-mm/yr; this compaction accounts for more than half of observed land subsidence in the region. Glacial isostatic adjustment, or the flexing of the Earth’s crust in response to glacier formation and melting, also likely contributes to land subsidence in the region.

  14. Reconnaissance geologic map of the Kuskokwim Bay region, southwest Alaska

    Science.gov (United States)

    Wilson, Frederic H.; Hults, Chad P.; Mohadjer, Solmaz; Coonrad, Warren L.

    2013-01-01

    The rocks of the map area range from Proterozoic age metamorphic rocks of the Kanektok metamorphic complex (Kilbuck terrane) to Quaternary age mafic volcanic rocks of Nunivak Island. The map area encompasses much of the type area of the Togiak-Tikchik Complex. The geologic maps used to construct this compilation were, for the most part, reconnaissance studies done in the time period from the 1950s to 1990s. Pioneering work in the map area by J.M. Hoare and W.L. Coonrad forms the basis for much of this map, either directly or as the stepping off point for later studies compiled here. Physiographically, the map area ranges from glaciated mountains, as much as 1,500 m high, in the Ahklun Mountains to the coastal lowlands of northern Bristol Bay and the Kuskokwim River delta. The mountains and the finger lakes (drowned fiords) on the east have been strongly affected by Pleistocene and Holocene glaciation. Within the map area are a number of major faults. The Togiak-Tikchik Fault and its extension to the northeast, the Holitna Fault, are considered extensions of the Denali fault system of central Alaska. Other sub-parallel faults include the Golden Gate, Sawpit, Goodnews, and East Kulukak Faults. Northwest-trending strike-slip faults crosscut and offset northeast-trending fault systems. Rocks of the area are assigned to a number of distinctive lithologic packages. Most distinctive among these packages are the high-grade metamorphic rocks of the Kanektok metamorphic complex or Kilbuck terrane, composed of a high-grade metamorphic orthogneiss core surrounded by greenschist and amphibolite facies schist, gneiss, and rare marble and quartzite. These rocks have yielded radiometric ages strongly suggestive of a 2.05 Ga emplacement age. Poorly known Paleozoic rocks, including Ordovician to Devonian and Permian limestone, are found east of the Kanektok metamorphic complex. A Triassic(?) ophiolite complex is on the southeast side of Kuskokwim Bay; otherwise only minor Triassic

  15. Delft Delta Design : The Houston Galveston Bay Region, Texas, USA

    NARCIS (Netherlands)

    Bedient, P.B.; Berchum, E.; Blackburn, J.B.; De Boer, R.; Van Brakel, S.; Van Breukelen, M.; Brody, S.D.; Cao, Q.; Colbert, T.M.; Cunningham, S.W.; Dupuits, G.; Van den Ende, I.; Gunnewijk, R.; Heeringa, T.; Hogendoorn, D.; Bubu Hsun Ho, T.; Huang, S.Y.; Janssen, M.; Karimi, I.; Kelderman, R.; Kok, M.; Kuipers, A.; Van Ledden, M.; Lendering, K.T.; Liao, Y.C.; Liu, F.; Van Loon-Steensma, J.; De Milliano, A.; Merrell, W.J.; Meyer, V.J.; Mooyaart, L.; Newman, G.; Stoeten, K.; Rippi, K.; Roukens, G.; Ruijs, M.; Samson, K.; Schlepers, M.; Slinger, J.H.; Smulders, J.; Van der Toorn, A.; Van Boxelaere, H.; De Vries, P.; Wang, D.; Yam, A.A.; Kothuis, B.L.M.; Brand, A.D.; Sebastian, A.G.; Nillesen, A.L.; Jonkman, S.N.

    2015-01-01

    In 2008, Hurricane Ike devastated Bolivar Peninsula, narrowly missing the more heavily industrialized and populated areas in the region. In the aftermath of the hurricane, the Severe Storm Prediction, Education and Evacuation from Disasters (SSPEED) Center at Rice University in Houston, and Texas

  16. Generalized least squares and empirical Bayes estimation in regional partial duration series index-flood modeling

    DEFF Research Database (Denmark)

    Madsen, Henrik; Rosbjerg, Dan

    1997-01-01

    A regional estimation procedure that combines the index-flood concept with an empirical Bayes method for inferring regional information is introduced. The model is based on the partial duration series approach with generalized Pareto (GP) distributed exceedances. The prior information of the model...... families of prior distributions. The regional method is applied to flood records from 48 New Zealand catchments. In the case of a strongly heterogeneous intersite correlation structure, the GLS procedure provides a more efficient estimate of the regional GP shape parameter as compared to the usually...

  17. Review of wastewater problems and wastewater-management planning in the San Francisco Bay region, California

    Science.gov (United States)

    Hines, Walter G.

    1973-01-01

    The San Francisco Bay region has suffered adverse environmental effects related to the discharge of municipal-, industrial-, and agricultural- wastewater and storm-water runoff. Specific pollutional properties of theses discharges are not well understood in all cases although the toxic materials and aquatic-plant nutrients (biostimulants) found in municipal and industrial waterwater are considered to be a major cause of regional water-quality problems. Other water-quality problems in the region are commonly attributed to pesticides found in agricultural wastewater and potentially pathogenic bacteria in municipal-wastewater discharges and in storm-water runoff. The geographical distribution and magnitude of wastewater discharges in the bay region, particularly those from municipalities and industries, is largely a function of population, economic growth, and urban development. As might be expected, the total volume of wastewater has increased in a trend paralleling this growth and development. More significant, perhaps, is the fact that the total volume parameters such as BOD (biochemical oxygen demand), biostimulant concentrations, and toxicity, has increased despite large expenditures on new and improved municipal- and industrial-wastewater-treatment plants. Also, pollutant loadings from other major source, such as agriculture and storm-water runoff, have increased. At the time of writing (1972), many Federal, State, regional, and local agencies are engaged in a comprehensive wastewater-management-planning effort for the entire bay region. Initial objectives of this planning effort are: (1) the consolidation and coordination of loosely integrated wastewater-management facilities and (2) the elimination of wastewater discharges to ecologically sensitive areas, such as fresh-water streams and shallow extremities of San Francisco Bay. There has been some investigation of potential long-range wastewater-management alternatives based upon disposal in deep water in the

  18. Analysis of temperature field in the Banderas Bay Region between June 2009 to June 2012

    Science.gov (United States)

    Carrillo-Gonzalez, F. M.; Cornejo-Lopez, V. M.; Morales-Hernández, J. C.

    2012-12-01

    We present the spatial and temporary analysis of temperature fields monitored hourly and monthly throughout the year in the Banderas Bay region between the period June 2009 to June 2011. The study area is the atmospheric basin of Banderas Bay, between of Puerto Vallarta Jal. and Puerto Vallarta New Nay., in 20.66381 N,-105.20574W. The data used was obtained from the Atmospheric Monitoring Network in the Banderas Bay region, which comprises of at least 10 automatic weather stations distributed heterogeneously throughout the study area, which provide data on major meteorological variables at 10 minute intervals. It has been observed that the behavior throughout the year of major weather variables are determined by local processes (valley and breeze circulation) primarily and macro-scale phenomena (presence of the North Pacific anticyclone and trade winds). Greater thermal amplitude in the mountain regions of the River Ameca Valley, compared to coastal zones, with the latter influenced by the sea surface temperature. We registered small heat islands in urbane areas, which gives background information for future studies on pollution, health, prevention of natural disasters etc.

  19. Environmental Engineering and Ecological Baseline Investigations along the Yukon River-Prudhoe Bay Haul Road.

    Science.gov (United States)

    1980-09-01

    Interior, uplands with only modest chamissonis, Carex albonigra, Draba cana, D. ma- topographic relief support taiga in its various counii, Erigeron...vegetation, land- been found on dry bluffs and terraces formed by form, microrelief, and slope information similar the Sagavanirktok River include Carex ...to refine our distribution maps for Arenaria *Prepared by D.A. Walker and P.1. Webber 45 L .. il l Iii . .. . ... -.... .. OF- . . -T . . . Table 10

  20. Sensitivity of Plant Communities and Soil Flora to Seawater Spills, Prudhoe Bay, Alaska,

    Science.gov (United States)

    1983-09-01

    within the profile. A similar during the 1980 observation period: Saxifraga op- situation probably prevails, but to a lesser extent, positifolia on the dry...Cassiope tetragona and Saxifraga oppositifolia, regardless of differences in microrelief (Fig. 7a-d). species that are of moderate importance in the...ssp. !-41ndifolia Saxifraga cernua L. Saxaragafoliolosa R. Br. Saxifraga hirculus L. Saxifraga opposififolia L. ssp. opposiifolia Sedum rosea (L

  1. Pre-ABoVE: Remotely Sensed Active Layer Thickness, Prudhoe Bay, Alaska, 1992-2000

    Data.gov (United States)

    National Aeronautics and Space Administration — Active layer thickness (ALT) is a critical parameter for monitoring the status of permafrost that is typically measured at specific locations using probing, in situ...

  2. Probabilistic estimation of numbers and costs of future landslides in the San Francisco Bay region

    Science.gov (United States)

    Crovelli, R.A.; Coe, J.A.

    2009-01-01

    We used historical records of damaging landslides triggered by rainstorms and a newly developed Probabilistic Landslide Assessment Cost Estimation System (PLACES) to estimate the numbers and direct costs of future landslides in the 10-county San Francisco Bay region. Historical records of damaging landslides in the region are incomplete. Therefore, our estimates of numbers and costs of future landslides are minimal estimates. The estimated mean annual number of future damaging landslides for the entire 10-county region is about 65. Santa Cruz County has the highest estimated mean annual number of damaging future landslides (about 18), whereas Napa, San Francisco, and Solano Counties have the lowest estimated mean numbers of damaging landslides (about 1 each). The estimated mean annual cost of future landslides in the entire region is about US $14.80 million (year 2000 $). The estimated mean annual cost is highest for San Mateo County ($3.24 million) and lowest for Solano County ($0.18 million). The annual per capita cost for the entire region will be about $2.10. Santa Cruz County will have the highest annual per capita cost at $8.45, whereas San Francisco County will have the lowest per capita cost at $0.31. Normalising costs by dividing by the percentage of land area with slopes equal to or greater than 17% indicates that San Francisco County will have the highest cost per square km ($7,101), whereas Santa Clara County will have the lowest cost per square km ($229). These results indicate that the San Francisco Bay region has one of the highest levels of landslide risk in the United States. Compared with landslide cost estimates from the rest of the world, the risk level in the Bay region seems high, but not exceptionally high.

  3. Air- and stream-water-temperature trends in the Chesapeake Bay region, 1960-2014

    Science.gov (United States)

    Jastram, John D.; Rice, Karen C.

    2015-12-14

    in-stream sediments, so understanding changes in stream-water temperature throughout the bay watershed is critical to resource managers seeking to restore the bay ecosystem.The U.S. Environmental Protection Agency (EPA) uses indicators that “represent the state or trend of certain environmental or societal conditions … to track and better understand the effects of changes in the Earth’s climate” (U.S. Environmental Protection Agency, 2014). Updates to these indicators are published biennially by the EPA. The U.S. Geological Survey (USGS), in cooperation with the EPA, has completed analyses of air- and stream-water-temperature trends in the Chesapeake Bay region to be included as an indicator in a future release of the EPA report.

  4. San Francisco Bay Area Baseline Trash Loading Summary Results, San Francisco Bay Area CA, 2012, US EPA Region 9

    Data.gov (United States)

    U.S. Environmental Protection Agency — The San Francisco Bay Area stormwater permit sets trash control guidelines for discharges through the storm drain system. The permit covers Alameda, Contra Costa,...

  5. Contaminant exposure and reproductive success of Ospreys (Pandion haliaetus) nesting in Chesapeake Bay regions of concern

    Science.gov (United States)

    Rattner, B.A.; McGowan, P.C.; Golden, N.H.; Hatfield, J.S.; Toschik, P.C.; Lukei, R.F.; Hale, R.C.; Schmitz-Afonso, I.; Rice, C.P.

    2004-01-01

    The Chesapeake Bay osprey population has more than doubled in size since restrictions were placed on the production and use of DDT and other toxic organochlorine contaminants in the 1970s. Ospreys are now nesting in the most highly polluted portions of the Bay. In 2000 and 2001, contaminant exposure and reproduction were monitored in ospreys nesting in regions of concern, including Baltimore Harbor and the Patapsco River, the Anacostia and middle Potomac rivers, and the Elizabeth River, and a presumed reference site consisting of the South, West, and Rhode rivers. A 'sample egg' from each study nest was collected for contaminant analysis, and the fate of eggs remaining in each nest (n = 14-16/site) was monitored at 7- to 10-day intervals from egg incubation through fledging of young. Ospreys fledged young in regions of concern (observed success: 0.88 -1.53 fledglings/active nest), although productivity was marginal for sustaining local populations in Baltimore Harbor and the Patapsco River and in the Anacostia and middle Potomac rivers. Concentrations of p,p'DDE and many other organochlorine pesticides or metabolites, total PCBs, some arylhydrocarbon receptor-active PCB congeners and polybrominated diphenyl ether congeners, and perfluorooctanesulfonate were often greater in sample eggs from regions of concern compared to the reference site. Nonetheless, logistic regression analyses did not provide evidence linking marginal productivity to p,p' -DDE, total PCBs, or arylhydrocarbon receptor-active PCB congener exposure in regions of concern. In view of the moderate concentrations of total PCBs in eggs from the reference site, concerns related to new and emerging toxicants, and the absence of ecotoxicological data for terrestrial vertebrates in many Bay tributaries, a more thorough spatial evaluation of contaminant exposure in ospreys throughout the Chesapeake may be warranted.

  6. Appearance of the persistently low tropopause temperature and ozone over the Bay of Bengal region

    Science.gov (United States)

    Jain, Shipra; Jain, A. R.; Mandal, T. K.

    2017-09-01

    This paper reports the observation of persistently low tropopause temperatures (100 hPa temperatures, T 100) and ozone at 100 hPa throughout the year as compared to the corresponding zonal mean values over the Bay of Bengal (BOB) region. The long term mean T 100 (i.e., from January 2006-December 2009) over the BOB is 2.2 K lower than the zonal mean values over this region. The multiple linear regression analysis has been carried out to study the role of convection and ozone in giving rise to the persistently low T 100 over the BOB. Results show that the low ozone mixing ratios contributes 1.2 K and convection contributes 0.35 K to the persistently low T 100. The contribution of convection to the persistent low T 100 is mainly during the boreal monsoon season.

  7. Repair of DNA damage induced by anthanthrene, a polycyclic aromatic hydrocarbon (PAH) without bay or fjord regions

    DEFF Research Database (Denmark)

    Madsen, Claus Desler; Johannessen, Christian; Rasmussen, Lene Juel

    2009-01-01

    is known about the repair of DNA damage resulting from metabolites from PAHs without bay and fjord regions. We have investigated the six-ringed PAH anthanthrene (dibenzo[def,mno]chrysene), which does not posses bay or fjord motifs. We analyzed the repair profile of human cell extracts and of cell cultures...... in response to DNA damage induced by cytochrome P450-activated anthanthrene. In cell extracts, functional nucleotide excision repair (NER) and mismatch repair (MMR) activities were necessary to trigger a response to anthanthrene metabolite-induced DNA damage. In cell cultures, NER was responsible...... proposed for metabolic activation of PAHs involves the cytochrome P450 enzymes. The DNA damaging potential of cytochrome P450-activated PAHs is generally associated with their bay and fjord regions, and the DNA repair response of PAHs containing such regions has been thoroughly studied. However, little...

  8. Regional Sediment Management Studies of Matagorda Ship Channel and Matagorda Bay System, Texas

    Science.gov (United States)

    2013-08-01

    4  2.1  Freshwater Flow into Lavaca and Matagorda Bays ..................................................... 4...as these processes interact with river influxes and tidal forcing from the Gulf of Mexico (GOM). The main challenge was to model mixed-sizes and... Freshwater Flow into Lavaca and Matagorda Bays Freshwater flow into Matagorda Bay is moderate and consists primarily of discharges from the Colorado

  9. Development of a management plan for coast live oak forests affected by sudden oak death in East Bay Regional Parks

    Science.gov (United States)

    Brice A. McPherson; Joshua O’Neill; Gregory Biging; Maggi Kelly; David L. Wood

    2015-01-01

    The East Bay Regional Park District maintains the largest urban park system in the United States, comprising over 45 000 ha, and more than 1900 km of trails, with extensive forests bordering residential areas. Sudden oak death (SOD), caused by the introduced oomycete Phytophthora ramorum, was first detected in a district park in 2001. Both...

  10. Fire history of the San Francisco East Bay region and implications for landscape patterns

    Science.gov (United States)

    Keeley, J.E.

    2005-01-01

    The San Francisco East Bay landscape is a rich mosaic of grasslands, shrublands and woodlands that is experiencing losses of grassland due to colonization by shrubs and succession towards woodland associations. The instability of these grasslands is apparently due to their disturbance-dependent nature coupled with 20th century changes in fire and grazing activity. This study uses fire history records to determine the potential for fire in this region and for evidence of changes in the second half of the 20th century that would account for shrubland expansion. This region has a largely anthropogenic fire regime with no lightning-ignited fires in most years. Fire suppression policy has not excluded fire from this region; however, it has been effective at maintaining roughly similar burning levels in the face of increasing anthropogenic fires, and effective at decreasing the size of fires. Fire frequency parallels increasing population growth until the latter part of the 20th century, when it reached a plateau. Fire does not appear to have been a major factor in the shrub colonization of grasslands, and cessation of grazing is a more likely immediate cause. Because grasslands are not under strong edaphic control, rather their distribution appears to be disturbance-dependent, and natural lightning ignitions are rare in the region, I hypothesize that, before the entrance of people into the region, grasslands were of limited extent. Native Americans played a major role in creation of grasslands through repeated burning and these disturbance-dependent grasslands were maintained by early European settlers through overstocking of these range lands with cattle and sheep. Twentieth century reduction in grazing, coupled with a lack of natural fires and effective suppression of anthropogenic fires, have acted in concert to favor shrubland expansion.

  11. Tempo-spatial analysis of water quality in tributary bays of the Three Gorges Reservoir region (China).

    Science.gov (United States)

    Tang, Jialiang; Wang, Tao; Zhu, Bo; Zhao, Pei; Xiao, Yi; Wang, Rui

    2015-11-01

    As a giant newly built man-made canyon-shaped reservoir, the Three Gorges Reservoir (TGR) receives much attention around China and other parts of the world. Bays were deemed to be the most critical zone for water management of TGR; thus, a 3.5-year temporal and spatial investigation was performed to disclose water quality variation in TGR bays and to elucidate the potential affecting factors based on an integrated hydrographical analysis. The results showed that TGR bays had been moderately polluted with averaged nitrogen (N) concentration over 2 mg L(-1) and phosphorus (P) concentration less than 0.1 mg L(-1) in dry season and while high P over 0.2 mg L(-1) and low N of 1.54 mg L(-1) in average in flooding season. The interaction of dam regulation and flooding events influenced the temporal pattern of water quality in the TGR bays, in which particulate nutrients dynamic played an important role. Urban effluents and agricultural catchment area also influenced water quality in the bays, showing local spatial distribution characteristics via diffusion mechanism. Backwater ends might be the most critical areas of water quality degradation. Alleviation measures had been proposed for sustainable development of TGR region.

  12. Investigating the environmental and socioeconomic impacts of sea level rise in the Galveston Bay, Texas region

    Science.gov (United States)

    Subedee, M.; Dotson, M.; Gibeaut, J. C.

    2016-02-01

    Anthropogenic effects throughout the twenty-first century, particularly greenhouse gas emissions, have contributed to global climatic and environmental changes. Sea level rise (SLR) is one of these changes which is occurring along the Texas Coast and is amplified by land subsidence. SLR along the northern Texas coast is impacting sensitive coastal environments as well as human populations, and industries and infrastructure supporting those populations. Sea level data from the NOAA gauge at Galveston Pier 21 has shown an increase of 2.08 feet in relative sea level in 100 years. Given an expected increase in the rate of sea level rise in the next decades, the purpose of this study is to provide an in-depth assessment on the effects of relative sea level rise on the habitat distribution of highly valuable coastal wetlands in the Galveston Bay region. This study also focuses on projecting the potential socioeconomic losses due to coastal flooding that is amplified by SLR in the region. In this study, three SLR scenarios are modeled: a scenario based on a linear extrapolation of satellite altimetry data (0.21 m by 2100); the IPCC's RCP8.5 mean scenario (0.74 m by 2100); and a high-end scenario (1.8 m by 2100) as proposed by Jevrejeva et al. (2014). A land subsidence rate calculated by developing a subsidence grid using GPS-measured subsidence monitoring and releveling data is added to all these scenarios. The Sea Level Affecting Marshes Model (SLAMM) is used to predict wetland conversion due to long-term SLR incorporating the processes of inundation, erosion, accretion, overwash, and saturation. Similarly, HAZUS-MH is used to evaluate the property damage to building stocks and the direct business interruption losses due to flooding caused by 100-year flood event scenario with three SLR scenarios. This coordinated research effort to assess the physical, environmental and policy impacts due to SLR is intended to enable policy-makers, managers, and the general public to

  13. Behavior and fate of spilled Prudhoe crude upon the Atigun River flood plain: Phase II, August 6-7 field assessment

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Observations obtained during the August 6th - 7th field surveys are part of the continuing assessment of the fate and effects of spilled Prudhoe crude upon the...

  14. Precambrian Crustal Evolution of the Hudson Bay Region: Insights from Receiver Function Analysis (Invited)

    Science.gov (United States)

    Thompson, D. A.; Bastow, I. D.; Helffrich, G. R.; Kendall, J. M.; Wookey, J.; Snyder, D. B.; Eaton, D. W.

    2009-12-01

    The processes that formed, thickened and thinned the early Earth's crust remain poorly known. The onset of modern plate tectonics, for example, could be as far back as the Hadean or as late as the Neoproterozoic. In many cratons, vertical processes are believed to have been dominant (dome-and-keel tectonics, e.g. Pilbara craton), while others are hypothesised to have formed by the progressive accretion of different terranes (e.g. Superior craton). The Hudson Bay region represents one of the largest areas of Precambrian geology on the planet, with ages spanning 2 billion years (3.9-1.8 Ga). The western Churchill province contains the predominantly Paleo- to Mesoarchean Rae domain and the Neoarchean Hearne domain, and is welded to the Superior craton by the Paleoproterozoic Trans-Hudson Orogen, a Himalayan scale feature which extends for more than 4500 km along strike. The Churchill has received comparatively little scientific investigation due to its remote location and harsh climate. In order to test hypotheses on crustal formation and evolution during the Precambrian, teleseismic receiver functions have been analysed for more than 30 stations located on the key geological features in the vicinity of Hudson Bay. Across the entire Rae domain, a dominantly felsic crust with a sharp Moho is observed. Little evidence exists to interpret the vast extent of the felsic crust in terms of subduction related processes. Within the granite-greenstone terranes of the Hearne domain, a more intermediate bulk composition and complex Moho signature may be representative of an oceanic affinity for the crust, suggesting accretionary processes acted there. In the Quebec-Baffin Island region, bulk crustal Vp/Vs ratios are dominated by effects associated with the Trans-Hudson Orogen, and appear to map out the first-order shape of the indenting lower-plate. Correlation between terrane age and receiver function-derived crustal structure suggests that the crust in northern Canada was

  15. Preliminary location and age database for invertebrate fossils collected in the San Francisco Bay region, California

    Science.gov (United States)

    Parker, John M.; West, William B.; Malmborg, William T.; Brabb, Earl E.

    2003-01-01

    Most geologic maps published for central California in the past century have been made without the benefit of microfossils. The age of Cretaceous and Tertiary rocks in the structurally complex sedimentary formations of the Coast Ranges is critical in determining stratigraphic succession and in determining whether the juxtapositon of similar appearing formations means that a fault is present. Since the 1930’s, at least, oil company geologists have used microfossils to assist them in geologic mapping and in determining the environments of deposition of sedimentary rocks. This information has been confidential, but in the past 20 years the attitude of petroleum companies about this information has changed, and much material is now available. We report here on approximately 4,700 samples, largely foraminifers, from surface localities in the San Francisco Bay region of California. The information contained here can be used to update geologic maps, to analyze the depth and temperature of ocean water covering parts of California during the Mesozoic and Cenozoic eras, and for solving other geologic problems.

  16. Infrasound Observations at the Lützow-Holm Bay region, East Antarctica

    Science.gov (United States)

    Kanao, M.; Murayama, T.; Yamamoto, M.; Ishihara, Y.; Kakinami, Y.

    2013-12-01

    Characteristic infrasound waves observed at Antarctic stations demonstrate physical interaction involving surface environmental changes in the continent and surrounding oceans. A Chaparral type infrasound sensor was installed at Syowa Station (SYO; 39E, 69S), East Antarctica, as one of the projects of the International Polar Year (IPY2007-2008). Continuous recording data during the three seasons in 2008-2010 clearly indicate a contamination of the background oceanic signals (microbaroms) with peaks between 4 and 10 s observed during a whole season. The peak amplitudes of the microbaroms has relatively lower amplitudes during austral winters, caused by a larger amount of sea-ice extending around the Lützow-Holm Bay near SYO, with decreasing ocean wave loading effects. Microbaroms measurements are a useful tool for characterizing ocean wave climate, complementing other oceanographic and geophysical data. In the austral summer in 2013, a few number of infrasound stations was established along the coast of LHB. Two different size of infrasound arrays were installed at SYO (100m spacing triangle) and S16 area on the continental ice sheet (1000m spacing triangle). In addition, isolated single stations were developed at two outcrops along the LHB. The new two infrasound arrays clearly detected the microbaroms with their propagating directions from the Southern Ocean. Moreover, characteristic signals associated with calving of the edge of glaciers, as well as the shock waves generated from meteorite injection at the Russian Republic on 15 February 2013. In this presentation, several kind of remarkable data are demonstrated. Detail measurements of the infrasound waves in Antarctica could be a new proxy for monitoring a regional environmental change together with temporal climate variations in polar region.

  17. Predicted Surface Displacements for Scenario Earthquakes in the San Francisco Bay Region

    Science.gov (United States)

    Murray-Moraleda, Jessica R.

    2008-01-01

    In the immediate aftermath of a major earthquake, the U.S. Geological Survey (USGS) will be called upon to provide information on the characteristics of the event to emergency responders and the media. One such piece of information is the expected surface displacement due to the earthquake. In conducting probabilistic hazard analyses for the San Francisco Bay Region, the Working Group on California Earthquake Probabilities (WGCEP) identified a series of scenario earthquakes involving the major faults of the region, and these were used in their 2003 report (hereafter referred to as WG03) and the recently released 2008 Uniform California Earthquake Rupture Forecast (UCERF). Here I present a collection of maps depicting the expected surface displacement resulting from those scenario earthquakes. The USGS has conducted frequent Global Positioning System (GPS) surveys throughout northern California for nearly two decades, generating a solid baseline of interseismic measurements. Following an earthquake, temporary GPS deployments at these sites will be important to augment the spatial coverage provided by continuous GPS sites for recording postseismic deformation, as will the acquisition of Interferometric Synthetic Aperture Radar (InSAR) scenes. The information provided in this report allows one to anticipate, for a given event, where the largest displacements are likely to occur. This information is valuable both for assessing the need for further spatial densification of GPS coverage before an event and prioritizing sites to resurvey and InSAR data to acquire in the immediate aftermath of the earthquake. In addition, these maps are envisioned to be a resource for scientists in communicating with emergency responders and members of the press, particularly during the time immediately after a major earthquake before displacements recorded by continuous GPS stations are available.

  18. Contaminant exposure and reproductive success of ospreys (Pandion haliaetus) nesting in Chesapeake Bay regions of concern

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Chesapeake Bay osprey population has more than doubled in size since restrictions were placed on the production and use of and other in the 1970s. Ospreys are...

  19. Recommendations for the conservation and management of humpback dolphins Sousa chinensis in the Algoa Bay region, South Africa

    Directory of Open Access Journals (Sweden)

    L. Karczmarski

    1998-02-01

    Full Text Available The natural history of humpback dolphins Sousa chinensis inhabiting the Algoa Bay region. Eastern Cape, South Africa, was investigated by means of land- and sea-based surveys undertaken between May 1991 and May 1994. This article reviews the findings which are relevant to the conservation of humpback dolphins and provides recommendations for both the conservation and management of this species in Eastern Cape waters. In general, humpback dolphins appear to be typical coastal dolphins which occur in small numbers, have low population growth and depend on restricted inshore resources. Establishment of protected areas where human impact could be limited or controlled seems to be the most effective conservation/management approach. Habitats critical for humpback dolphins in Eastern Cape waters (inshore rocky reefs and the dolphin's core areas in the Algoa Bay region have been identified. It is recommended that a conservation and management zone (marine sanctuary in the Algoa Bay region be established and a suitable site for it is identified. Given adequate legislation and proper management, this area could be used for the development of ecotourism, including dolphin-watch operations, which would further stimulate interest in coastal conservation.

  20. ASSESSMENT OF THE BLACK SEA ECOSYSTEM POLLUTION WITH COPPER AND CADMIUM IN SELECTED BAYS OF SEVASTOPOL REGION

    Directory of Open Access Journals (Sweden)

    Marcin Niemiec

    2015-11-01

    Full Text Available A high level of anthropopressure has been registered in Sevastopol region, connected with its strategic role as the main city in the region, but also due to Russian Black Sea Fleet stationing there for many years. A significant source of the Black Sea contamination in Sevastopol area is the industry located in this city, municipal waste and agriculture. Implementing measures aimed at protection of the Black Sea and the evolution of their results requires monitoring conducted in the regions with various levels of anthropopressure. The work was aimed at the assessment of copper and cadmium content in water and algae in selected bays of the Black Sea in the vicinity of Sevastopol. Samples of water and algae were collected in August 2012 from eight Sevastopol bays (Galubaja, Kozacha, Kamyshova, Kruhla, Strieletska, Pishchana, Pivdenna and Sevastopolska and from the open sea in the vicinity of Fiolent. Algae (Cystoseira barbata and Ulva rigida were collected from the same places. Collected water was preserved on the sampling place and brought to the laboratory where its copper and cadmium concentrations were assessed. Collected algae were rinsed in distilled water, dried, then homogenised and mineralised. Copper and cadmium content were determined in the mineralizates using ASA method with electrothermal atomisation. Cadmium concentration in water ranged from 0.13 to 1.74 µg Cd∙dm-3, and copper from 7.07 to 22.56 µg Cd∙dm-3. Considerable differences in the content of the analysed elements were registered in individual bays. The highest content was assessed in Galubaja and Sevastopolska bays, whereas the lowest one in the water collected in the open sea and in Pivdenna bay. Copper concentrations in the analysed algae fluctuated from 3.375 to 14.96 mg Cu∙kg-1 d.m. No differences were noted in this element content between the algae species. Cadmium content in the algae ranged from 0.133 to 1.133 mg Cd∙kg-1 d.m. Higher accumulation of cadmium

  1. An Approach to Understanding Complex Socio-Economic Impacts and Responses to Climate Disruption in the Chesapeake Bay Region

    Science.gov (United States)

    Schaefer, R. K.; Nix, M.; Ihde, A. G.; Paxton, L. J.; Weiss, M.; Simpkins, S.; Fountain, G. H.; APl GAIA Team

    2011-12-01

    In this paper we describe the application of a proven methodology for modeling the complex social and economic interactions of a system under stress to the regional issues that are tied to global climate disruption. Under the auspices of the GAIA project (http://gaia.jhuapl.edu), we have investigated simulating the complex interplay between climate, politics, society, industry, and the environment in the Chesapeake Bay Watershed and associated geographic areas of Maryland, Virginia, and Pennsylvania. This Chesapeake Bay simulation draws on interrelated geophysical and climate models to support decision-making analysis about the Bay. In addition to physical models, however, human activity is also incorporated via input and output calculations. For example, policy implications are modeled in relation to business activities surrounding fishing, farming, industry and manufacturing, land development, and tourism. This approach fosters collaboration among subject matter experts to advance a more complete understanding of the regional impacts of climate change. Simulated interactive competition, in which teams of experts are assigned conflicting objectives in a controlled environment, allow for subject exploration which avoids trivial solutions that neglect the possible responses of affected parties. Results include improved planning, the anticipation of areas of conflict or high risk, and the increased likelihood of developing mutually acceptable solutions.

  2. Executive summary: Benefit-cost evaluation of an intra-regional air service in the Bay Area and a technology assessment of transportation system investments. [regional planning for the San Francisco Bay area of California

    Science.gov (United States)

    Haefner, L. E.

    1978-01-01

    The benefits and costs that would result from an intra-regional air service operation in the San Francisco Bay area were determined by utilizing an iterative statistical decision model to evaluate combinations of commuter airport sites and surface transportation facilities in conjunction with service by a given commuter aircraft type in light of area regional growth alternatives and peak and off-peak regional travel patterns. The model evaluates such transportation option with respect to criteria of airline profitability, public acceptance, and public and private non-user costs. In so doing, it incorporates information on modal split, peak and off-peak use of the air commuter fleet, terminal and airport costs, development costs and uses of land in proximity to the airport sites, regional population shifts, and induced zonal shifts in travel demand. The model is multimodal in its analytic capability, and performs exhaustive sensitivity analysis.

  3. Late Holocene evolution of the Northeast intertidal region of Sepetiba Bay, Rio de Janeiro (Brazil

    Directory of Open Access Journals (Sweden)

    Anita Fernandes Souza Pinto

    2016-03-01

    Full Text Available This work is based on the study of the core T1 collected in the Guaratiba Mangrove, located on the northeastern margin of Sepetiba Bay. Few studies dealing with the application of benthic foraminifera to study sea level changes during the Holocene have been conducted in Sepetiba Bay, State of Rio de Janeiro, Brazil. In order to fill this gap, the core T1 was studied using textural, geochemical (carbonate, total organic carbon, total sulfur and stable isotopes evaluated in Ammonia tepida and microfaunal (benthic foraminifera data, unveiling paleoecological relationships of these organisms and the evolutionary scenario of Guaratiba Mangrove. Radiocarbon results indicate an estimated age of about 2400 yrs cal BP for the core base. Textural, geochemical and benthic foraminifera data suggest that the study area changed significantly during the last 2400 yrs cal BP. It experienced coastal waves action and shoreface processes in the period between ≈2.400-1.400 yrs cal BP; then, this phase gave place to a shallow marine environment similar to that found currently in internal and protected areas of Sepetiba Bay, between ≈1.400-350 yrs cal BP. Thenceforth, the study area evolved to the present mangrove environment. Factors related to climatic oscillations and the formation, evolution and events of rupture of Marambaia sand ridge influenced the late Holocene evolution of the northeast intertidal area of Sepetiba Bay.

  4. Aliphatic and aromatic hydrocarbon, organochlorine pesticide, and trace element concentrations in six fox livers from the Prudhoe Bay Oilfield, Alaska

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This study was a portion of a multi-year assessment of contaminant concentrations from a variety of biotic and abiotic samples on the North Slope of Alaska. The...

  5. Fish impacts in the Atigun River from Prudhoe Bay crude oil: Investigations of Phase I and II

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report summarizes Phase I and II, Environmental Protection Agency funded damage assessment investigation on fish observation in the Atigun River associated with...

  6. Moving Northward? First Record of Spilocuma Watlingi (Crustacea: Cumacea: Bodotriidae) in Mid-Atlantic Region, Maryland Coastal Bays, USA

    Science.gov (United States)

    Morales-Nunez, A. G.; Chigbu, P.

    2016-02-01

    Spilocuma watlingi is a species of Cumacea that appears to be confined to protected beaches inside of barrier islands. It ranges in distribution from the northern Gulf of Mexico (Alabama) to the South Atlantic Bight (Georgia and North Carolina) on the east coast of the United States. A benthic invertebrate sample collected from Sinepuxent Bay (Maryland) in August 2014, contained one ovigerous female of Spilocuma watlingi which is being reported for the first time in Maryland Coastal Bays (MCBs) and the Mid-Atlantic region. The occurrence of S. watlingi in the MCBs represents a major range extension for the species. The likely vectors for its introduction in the region include ship ballast water and hull fouling. It is also possible that because of climate change S. watlingi has begun to invade temperate waters, or the species was overlooked during previous studies. If so, this underscores the need for more studies on the diversity and abundance of benthic marine invertebrates in the Mid-Atlantic region.

  7. Data from theodolite measurements of creep rates on San Francisco Bay region faults, California: 1979-2001

    Science.gov (United States)

    Galehouse, Jon S.

    2002-01-01

    My purpose is to make our creep data on San Francisco Bay region active faults available to the scientific research community. My student research assistants and I measured creep (aseismic slip) rates on these faults from 1979 until my retirement from the project in 2001. These data are further described in my final technical report as principal investigator, which summarizes results from 22 September 1979 through 28 February 2001 (Galehouse, 2001). We made over 2,600 creep measurements, about one-third in the ten years prior to the Loma Prieta earthquake (LPEQ) and two-thirds in the 11.4 years following it. The measurements are continuing to be made by members of the Geosciences Department at San Francisco State University (SFSU) under the direction of Karen Grove and John Caskey. A complete analysis of our results obtained on the Hayward fault is presented in Lienkaemper, Galehouse, and Simpson (2001). A formal report based on the entire San Francisco Bay region data set is in preparation. Data sheets for each site along the fault are available for downloading in Excel format to facilitate analysis of the data. They are also available as tab-delimited raw data. The data include all regular measurement sites, SF–1 through SF–34, and the 20 SFSU and U.S. Geological Survey (USGS) afterslip sites on the Hayward fault.

  8. Late Pleistocene eolian features in southeastern Maryland and Chesapeake Bay region indicate strong WNW-NW winds accompanied growth of the Laurentide Ice Sheet

    Science.gov (United States)

    Markewich, H.W.; Litwin, R.J.; Pavich, M.J.; Brook, G.A.

    2009-01-01

    Inactive parabolic dunes are present in southeastern Maryland, USA, along the east bank of the Potomac River. More elongate and finer-grained eolian deposits and paha-like ridges characterize the Potomac River-Patuxent River upland and the west side of Chesapeake Bay. These ridges are streamlined erosional features, veneered with eolian sediment and interspersed with dunes in the low-relief headwaters of Potomac- and Patuxent-river tributaries. Axis data for the dunes and ridges indicate formation by WNW-NW winds. Optically stimulated luminescence and radiocarbon age data suggest dune formation from ??? 33-15??ka, agreeing with the 30-13??ka ages Denny, C.S., Owens, J.P., Sirkin, L., Rubin, M., 1979. The Parsonburg Sand in the central Delmarva Peninsula, Maryland and Delaware. U.S. Geol. Surv. Prof. Pap. 1067-B, 16??pp. suggested for eolian deposits east of Chesapeake Bay. Age range and paleowind direction(s) for eolian features in the Bay region approximate those for late Wisconsin loess in the North American midcontinent. Formation of midcontinent loess and Bay-region eolian features was coeval with rapid growth of the Laurentide Ice Sheet and strong cooling episodes (??18O minima) evident in Greenland ice cores. Age and paleowind-direction coincidence, for eolian features in the midcontinent and Bay region, indicates strong mid-latitude WNW-NW winds for several hundred kilometers south of the Laurentide glacial terminus that were oblique to previously simulated anticyclonic winds for the last glacial maximum.

  9. Microcystin in aquatic food webs of the Baltic and Chesapeake Bay regions

    Science.gov (United States)

    Bukaveckas, Paul A.; Lesutienė, Jūratė; Gasiūnaitė, Zita R.; Ložys, Linas; Olenina, Irina; Pilkaitytė, Renata; Pūtys, Žilvinas; Tassone, Spencer; Wood, Joseph

    2017-05-01

    We undertook a comparative study of the James River Estuary, a sub-estuary of Chesapeake Bay, and the Curonian Lagoon, a sub-estuary of the Baltic Sea, to better understand the factors that determine the presence and persistence of algal toxins in food webs. Over a 2-year period, we measured microcystin concentrations in water, sediment and biota (fish and shellfish) at both sites. Across both food webs we found highest levels of microcystin among consumers of suspended particulate matter, including planktivorous fishes and filter-feeding shellfish, and lower levels of toxin among piscivores, scavengers and benthic omnivores. Despite similar levels of microcystin in the water column at the two sites, we observed higher toxin levels in fish and sediments of the Curonian Lagoon. We attribute this difference to the legacy of prior toxic cyanobacteria blooms in the Curonian Lagoon and hydrologic factors that result in a predominance of autochthonously-derived organic matter in the sediments at this site. Our results suggest that a consideration of species-specific differences in feeding habits, and organic matter sources supporting food webs are important to understanding the accumulation and persistence of algal toxins in food webs and should therefore be considered in assessment of risks to aquatic biota and human health.

  10. NODC Standard Product: Coastal Change Analysis Program (C-CAP) Chesapeake Bay Region Data from 1984 to 1989 on CD-ROM (NODC Accession 9200303)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data set on this CD-ROM shows changes in land cover for the Chesapeake Bay region over the 5-year interval from 1984 to 1988-89. The data set was produced...

  11. Probabilistic Methodology for Estimation of Number and Economic Loss (Cost) of Future Landslides in the San Francisco Bay Region, California

    Science.gov (United States)

    Crovelli, Robert A.; Coe, Jeffrey A.

    2008-01-01

    The Probabilistic Landslide Assessment Cost Estimation System (PLACES) presented in this report estimates the number and economic loss (cost) of landslides during a specified future time in individual areas, and then calculates the sum of those estimates. The analytic probabilistic methodology is based upon conditional probability theory and laws of expectation and variance. The probabilistic methodology is expressed in the form of a Microsoft Excel computer spreadsheet program. Using historical records, the PLACES spreadsheet is used to estimate the number of future damaging landslides and total damage, as economic loss, from future landslides caused by rainstorms in 10 counties of the San Francisco Bay region in California. Estimates are made for any future 5-year period of time. The estimated total number of future damaging landslides for the entire 10-county region during any future 5-year period of time is about 330. Santa Cruz County has the highest estimated number of damaging landslides (about 90), whereas Napa, San Francisco, and Solano Counties have the lowest estimated number of damaging landslides (5?6 each). Estimated direct costs from future damaging landslides for the entire 10-county region for any future 5-year period are about US $76 million (year 2000 dollars). San Mateo County has the highest estimated costs ($16.62 million), and Solano County has the lowest estimated costs (about $0.90 million). Estimated direct costs are also subdivided into public and private costs.

  12. Identifying Fossil Shell Resources via Geophysical Surveys: Chesapeake Bay Region, Virginia

    Science.gov (United States)

    2016-05-01

    330 ft) along a given seismic line and (2) the Matlab method includes incorrect FOS locations. In contrast, the hand-digitization method generates a...northwest corner of the site. Here, the Matlab method indicated substantial FOS regions. Core and seismic data, however, indicate this region is...feasibility of using acoustic sub-bottom seismic surveys for determining the location and quantity of buried FOS. Over 280 miles of seismic surveys and

  13. Supporting Coastal Management Decisions in the Face of Sea-Level Rise: Case Study for the Chesapeake Bay Region

    Science.gov (United States)

    Staudt, A. C.; Glick, P.; Clough, J. S.; Nunley, B.

    2008-12-01

    Sea-level rise needs to be a major consideration in regional coastal management and ecological restoration plans. The National Wildlife Federation has initiated a multi-pronged strategy for assisting decision makers at government agencies that manage near-shore ecosystems in several vulnerable coastal regions. Results from our work in the Chesapeake Bay region will be presented. This strategy involves: (1) Detailed modeling of how coastal habitats will migrate in response to a range of sea-level rise scenarios. For this work, we used the Sea Level Affecting Marshes Model (SLAMM), which simulates the dominant processes involved in wetland conversions and shoreline modifications during long-term sea-level rise and takes into consideration localized changes in land elevation due to geological and ecological factors. These model results provide specific information about the locations that are likely to experience shifts in coastal marshes, swamps, beaches, and other habitats due to sea-level rise at a scale that is relevant to regional decision making. (2) Extensive literature review and analysis of habitat, fish, and wildlife impacts potentially resulting from expected sea-level rise and other local climate changes. Synthesizing the available research is an important service for natural resource agencies that are only beginning to consider climate impacts on ecosystems and natural resources. (3) Analysis of government programs and policies relevant to coastal management and identification of opportunities to revise these policies in light of projected climate changes. An important aspect of this analysis is meeting with key decision makers at relevant state fish and wildlife agencies to better understand the factors that affect their abilities to effect policy changes. (4) Proactive campaign to share our results with diverse audiences. We have developed different research products, ranging from a technical report of the modeling results to short report briefs, to

  14. Lateral extension of π conjugation along the bay regions of bisanthene through a diels-alder cycloaddition reaction

    KAUST Repository

    Li, Jinling

    2011-11-14

    Diels-Alder cycloaddition reactions at the bay regions of bisanthene (1) with dienophiles such as 1,4-naphthoquinone have been investigated. The products were submitted to nucleophilic addition followed by reductive aromatization reactions to afford the laterally extended bisanthene derivatives 2 and 3. Attempted synthesis of a larger expanded bisanthene 4 revealed an unexpected hydrogenation reaction at the last reductive aromatization step. Unusual Michael addition was observed on quinone 14, which was obtained by Diels-Alder reaction between 1 and 1,4-anthraquinone. Compounds 1-3 exhibited near-infrared (NIR) absorption and emission with high-to-moderate fluorescent quantum yields. Their structures and absorption spectra were studied by density function theory and non-planar twisted structures were calculated for 2 and 3. All compounds showed amphoteric redox behavior with multiple oxidation/reduction waves. Oxidative titration with SbCl 5 gave stable radical cations, and the process was followed by UV/Vis/NIR spectroscopic measurements. Their photostability was measured and correlated to their different geometries and electronic structures. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Geology, geochronology, and paleogeography of the southern Sonoma volcanic field and adjacent areas, northern San Francisco Bay region, California

    Science.gov (United States)

    Wagner, David L.; Saucedo, George J.; Clahan, Kevin B.; Fleck, Robert J.; Langenheim, Victoria E.; McLaughlin, Robert J.; Sarna-Wojcicki, Andrei M.; Allen, James R.; Deino, Alan L.

    2011-01-01

    Recent geologic mapping in the northern San Francisco Bay region (California, USA) supported by radiometric dating and tephrochronologic correlations, provides insights into the framework geology, stratigraphy, tectonic evolution, and geologic history of this part of the San Andreas transform plate boundary. There are 25 new and existing radiometric dates that define three temporally distinct volcanic packages along the north margin of San Pablo Bay, i.e., the Burdell Mountain Volcanics (11.1 Ma), the Tolay Volcanics (ca. 10–8 Ma), and the Sonoma Volcanics (ca. 8–2.5 Ma). The Burdell Mountain and the Tolay Volcanics are allochthonous, having been displaced from the Quien Sabe Volcanics and the Berkeley Hills Volcanics, respectively. Two samples from a core of the Tolay Volcanics taken from the Murphy #1 well in the Petaluma oilfield yielded ages of 8.99 ± 0.06 and 9.13 ± 0.06 Ma, demonstrating that volcanic rocks exposed along Tolay Creek near Sears Point previously thought to be a separate unit, the Donnell Ranch volcanics, are part of the Tolay Volcanics. Other new dates reported herein show that volcanic rocks in the Meacham Hill area and extending southwest to the Burdell Mountain fault are also part of the Tolay Volcanics. In the Sonoma volcanic field, strongly bimodal volcanic sequences are intercalated with sediments. In the Mayacmas Mountains a belt of eruptive centers youngs to the north. The youngest of these volcanic centers at Sugarloaf Ridge, which lithologically, chemically, and temporally matches the Napa Valley eruptive center, was apparently displaced 30 km to the northwest by movement along the Carneros and West Napa faults. The older parts of the Sonoma Volcanics have been displaced at least 28 km along the Rodgers Creek fault since ca. 7 Ma. The Petaluma Formation also youngs to the north along the Rodgers Creek–Hayward fault and the Bennett Valley fault. The Petaluma basin formed as part of the Contra Costa basin in the Late Miocene and

  16. Neogene contraction between the San Andreas fault and the Santa Clara Valley, San Francisco Bay region, California

    Science.gov (United States)

    McLaughlin, R.J.; Langenheim, V.E.; Schmidt, K.M.; Jachens, R.C.; Stanley, R.G.; Jayko, A.S.; McDougall, K.A.; Tinsley, J.C.; Valin, Z.C.

    1999-01-01

    In the southern San Francisco Bay region of California, oblique dextral reverse faults that verge northeastward from the San Andreas fault experienced triggered slip during the 1989 M7.1 Loma Prieta earthquake. The role of these range-front thrusts in the evolution of the San Andreas fault system and the future seismic hazard that they may pose to the urban Santa Clara Valley are poorly understood. Based on recent geologic mapping and geophysical investigations, we propose that the range-front thrust system evolved in conjunction with development of the San Andreas fault system. In the early Miocene, the region was dominated by a system of northwestwardly propagating, basin-bounding, transtensional faults. Beginning as early as middle Miocene time, however, the transtensional faulting was superseded by transpressional NE-stepping thrust and reverse faults of the range-front thrust system. Age constraints on the thrust faults indicate that the locus of contraction has focused on the Monte Vista, Shannon, and Berrocal faults since about 4.8 Ma. Fault slip and fold reconstructions suggest that crustal shortening between the San Andreas fault and the Santa Clara Valley within this time frame is ~21%, amounting to as much as 3.2 km at a rate of 0.6 mm/yr. Rates probably have not remained constant; average rates appear to have been much lower in the past few 100 ka. The distribution of coseismic surface contraction during the Loma Prieta earthquake, active seismicity, late Pleistocene to Holocene fluvial terrace warping, and geodetic data further suggest that the active range-front thrust system includes blind thrusts. Critical unresolved issues include information on the near-surface locations of buried thrusts, the timing of recent thrust earthquake events, and their recurrence in relation to earthquakes on the San Andreas fault.

  17. Analysis of mitochondrial control region nucleotide sequences from Baffin Bay beluga, (Delphinapterus leucas: detecting pods or sub-populations?

    Directory of Open Access Journals (Sweden)

    Per Jakob Palsbøll

    2002-07-01

    Full Text Available We report the results of an analysis of the variation in the nucleotide sequence of the mitochondrial control region obtained in 218 samples collected from belugas, Delphinapterus leucas, around the Baffin Bay. We detected multiple instances of significant heterogeneity in the distribution of genetic variation among the analyzed mitochondrial control region sequences on a spatial as well as temporal scale indicating a high degree of maternal population structure. The detection of significant levels of heterogeneity between samples collected in different years but within the same area and season was unexpected. Re-examination of earlier results presented by Brown Gladden and coworkers also revealed temporal genetic heterogeneity within the one area where sufficient (n>15 samples were collected in multiple years. These findings suggest that non-random breeding and maternally directed site-fidelity are not the sole causes of genetic heterogeneity among belugas but that a matrilineal pod structure might cause significant levels of genetic heterogeneity as well, even within the same area. We propose that a maternal pod structure, which has been shown to be the cause of significant genetic heterogeneity in other odontocetes, may add to the overall level of heterogeneity in the maternally inherited DNA and hence that much of the spatial heterogeneity observed in this and previous studies might be attributed to pod rather than population structure. Our findings suggest that it is important to estimate the contribution of pod structure to overall heterogeneity before defining populations or management units in order to avoid interpreting heterogeneity due to sampling of different pods as different populations/management units.

  18. San Francisco Bay Water Quality Improvement Fund Project Locations, San Francisco CA, 2017, US EPA Region 9

    Data.gov (United States)

    U.S. Environmental Protection Agency — The San Francisco Bay Water Quality Improvement Fund is a competitive grant program that is helping implement TMDLs to improve water quality, protect wetlands, and...

  19. San Francisco Bay Water Quality Improvement Fund Map Service, San Francisco CA, 2012, US EPA Region 9

    Data.gov (United States)

    U.S. Environmental Protection Agency — The San Francisco Bay Water Quality Improvement Fund is a competitive grant program that is helping implement TMDLs to improve water quality, protect wetlands, and...

  20. Contrasting sedimentation patterns in two semi-enclosed mesotidal bays along the west and south coasts of Korea controlled by their orientation to the regional monsoon climate

    Science.gov (United States)

    Hong, Seok Hwi; Chun, Seung Soo; Chang, Tae Soo; Jang, Dae Geon

    2017-08-01

    Sedimentation patterns of tidal flats along the Korean west coast have long been known to be largely controlled by the monsoon climate. On the other hand, much less is known about the effect of the monsoon on sedimentation in coastal embayments with mouths of different geographic orientations. Good examples are Hampyeong and Yeoja bays along the west and south coasts, respectively. Both have narrow entrances, but their mouths open toward the northwest and the south, respectively. With mean tidal ranges of 3.46 and 3.2 m, respectively, the two bays experience similar tidal regimes and are hence excellent candidates to compare the effect of different exposure to the same regional monsoon climate on their respective sediment distribution patterns. The winter monsoon, in particular, is characterized by strong northwesterly winds that directly impact the west coast, but blow offshore along the south coast. For the purpose of this study, surficial sediment samples were collected from intertidal and subtidal flats of the two bays, both in summer and winter. Grain-size analyses were carried out by sieving (sand fraction) and Sedigraph (mud fraction). In the case of Yeoja Bay, the sediments consist mostly of mud (mean grain sizes of 5.4 to 8.8 phi). Seasonal changes are very subtle, the sediments being slightly coarser in summer when silt-dominated sediments are supplied by two streams to the northern parts of the bay in response to heavy rainfall. With the exception of the deeper tidal channels, Yeoja Bay is characterized by a thick mud blanket the year round, which is modulated by processes associated with the summer monsoon that predominantly blows from the east. Textural parameters suggest severely restricted sediment mixing on the subtidal and intertidal flats, the overall low energy situation preventing sands from reaching the tidal flats. The sediments of Hampyeong Bay, by contrast, are characterized by a distinct shoreward fining trend. Mean grain sizes average

  1. Histological characterization of Sticholecitha serpentis Prudhoe, 1949 (digenea, bieriidae, sticholecithinae, parasite of Bothrops moojeni Hoge, 1966 (serpentes, viperidae

    Directory of Open Access Journals (Sweden)

    TB. Silva

    2005-12-01

    Full Text Available The aim of this study was to evaluate the morphology of the species Sticholecitha serpentis Prudhoe, 1949 by means of histological procedures. Helminths were previously fixed in Railliet & Henry solution, uncompressed and were included in 2-hydroxyethyl-methacrylate. Longitudinal and transverse serial sections with a 4-mum thickness were performed in a microtome (Leica RM 2165, stained with haematoxylin-eosin and then analyzed in a computerized image analysis system (Qwin Lite 2.5, Leica. Structures of systematic value, such as oral sucker, acetabulum, prepharynx, pharynx, esophagus, intestinal caeca, vitelline glands, ovary, uterus, cirrus pouch and testicles were described. Structures that were poorly visible in total preparations were also observed and described, such as efferent ducts, ejaculatory duct, prostate, seminal vesicle, seminal receptacle, Laurer’s channel, Mehlis’ gland, vitelline ducts, metraterm, genital atrium, digestive glands and excretory vesicle. We demonstrated that histological analysis can supply important data regarding the morphological characterization of S. serpentis and will be able to contribute to systematic studies of trematodes.

  2. Carbon isotopic fractionation in macroalgae from Cádiz Bay (Southern Spain): Comparison with other bio-geographic regions

    Science.gov (United States)

    Mercado, Jesús M.; de los Santos, Carmen B.; Lucas Pérez-Lloréns, J.; Vergara, Juan J.

    2009-11-01

    The 13C signature of forty-five macroalgal species from intertidal zones at Cádiz Bay was analysed in order to research the extension of diffusive vs. non-diffusive utilisation of dissolved inorganic carbon (DIC) and to perform a comparison with data published for other bio-geographic regions. The ∂ 13C values ranged from -6.8‰ to -33‰, although the span of variation was different depending on the taxa. Thus, ∂ 13C for Chlorophyta varied from -7‰ ( Codium adhaerens) to -29.6‰ ( Flabellia petiolata), while all the Phaeophyceae (excepting Padina pavonica with ∂ 13C higher than -10‰) had values between -10‰, and -20‰. The widest variation range was recorded in Rhodophyta, from values above -10‰ ( Liagora viscida) to values lower than -30‰ obtained in three species belonging to the subclass Rhodymeniophycidae. Accordingly, the mean ∂ 13C value calculated for red algae (-20.2‰) was significantly lower than that for brown (-15.9‰) and green algae (-15.6‰). Most of the analysed red algae were species inhabiting crevices and the low intertidal fringe which explains that, on average, the shaded-habitat species had a ∂ 13C value lower than those growing fully exposed to sun (i.e. in rockpools or at the upper intertidal zone). The comparison between the capacity for non-diffusive use of DIC (i.e. active or facilitated transport of HCO 3- and/or CO 2) and the ∂ 13C values reveals that values more negative than -30‰ indicate that photosynthesis is dependent on CO 2 diffusive entry, whereas values above this threshold would not indicate necessary the operation of a non-diffusive DIC transport mechanism. Furthermore, external carbonic anhydrase activity ( extCA) and ∂ 13C values were negatively correlated indicating that the higher the dependence of the photosynthesis on the CO 2 supplied from HCO 3- via extCA, the lower the ∂ 13C in the algal material. The comparison between the ∂ 13C values obtained for the analysed species and those

  3. Land Use and Land Cover, Current land use layer developed by Bay-Lake Regional Planning Commission as part of the County's 2009 Smart Growth Plan., Published in 2008, 1:2400 (1in=200ft) scale, Manitowoc County Government.

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — Land Use and Land Cover dataset current as of 2008. Current land use layer developed by Bay-Lake Regional Planning Commission as part of the County's 2009 Smart...

  4. Humboldt Bay Benthic Habitats 2009 Aquatic Setting

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Humboldt Bay is the largest estuary in California north of San Francisco Bay and represents a significant resource for the north coast region. Beginning in 2007 the...

  5. Humboldt Bay, California Benthic Habitats 2009 Geoform

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Humboldt Bay is the largest estuary in California north of San Francisco Bay and represents a significant resource for the north coast region. Beginning in 2007 the...

  6. Humboldt Bay, California Benthic Habitats 2009 Biotic

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Humboldt Bay is the largest estuary in California north of San Francisco Bay and represents a significant resource for the north coast region. Beginning in 2007 the...

  7. Humboldt Bay, California Benthic Habitats 2009 Geodatabase

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Humboldt Bay is the largest estuary in California north of San Francisco Bay and represents a significant resource for the north coast region. Beginning in 2007 the...

  8. Sources of suspended-sediment flux in streams of the chesapeake bay watershed: A regional application of the sparrow model

    Science.gov (United States)

    Brakebill, J.W.; Ator, S.W.; Schwarz, G.E.

    2010-01-01

    We describe the sources and transport of fluvial suspended sediment in nontidal streams of the Chesapeake Bay watershed and vicinity. We applied SPAtially Referenced Regressions on Watershed attributes, which spatially correlates estimated mean annual flux of suspended sediment in nontidal streams with sources of suspended sediment and transport factors. According to our model, urban development generates on average the greatest amount of suspended sediment per unit area (3,928 Mg/km2/year), although agriculture is much more widespread and is the greatest overall source of suspended sediment (57 Mg/km2/year). Factors affecting sediment transport from uplands to streams include mean basin slope, reservoirs, physiography, and soil permeability. On average, 59% of upland suspended sediment generated is temporarily stored along large rivers draining the Coastal Plain or in reservoirs throughout the watershed. Applying erosion and sediment controls from agriculture and urban development in areas of the northern Piedmont close to the upper Bay, where the combined effects of watershed characteristics on sediment transport have the greatest influence may be most helpful in mitigating sedimentation in the bay and its tributaries. Stream restoration efforts addressing floodplain and bank stabilization and incision may be more effective in smaller, headwater streams outside of the Coastal Plain. ?? 2010 American Water Resources Association. No claim to original U.S. government works.

  9. Movement patterns of Antillean manatees in Chetumal Bay (Mexico) and coastal Belize: A challenge for regional conservation

    Science.gov (United States)

    Castelblanco-Martínez, Delma Nataly; Padilla-Saldivar, J.; Hernández-Arana, Héctor Abuid; Slone, D.H.; Reid, J.P.; Morales-Vela, B.

    2013-01-01

    Information from 15 satellite-tracked Antillean manatees (Trichechus manatus manatus) was analyzed in order to assess individual movements, home ranges, and high-use areas for conservation decisions. Manatees were captured in Chetumal Bay, Mexico, and tagged with Argos-monitored satellite transmitters. Location of the manatees and physical characteristics were assessed to describe habitat properties. Most manatees traveled to freshwater sources. The Maximum Area Size (MAS) for each manatee was determined using the observation-area method. Additional kernel densities of 95% home range and 50% Center of Activity (COA) were also calculated, with manatees having 1–3 COAs. Manatees exhibited two different movement patterns: remaining in Chetumal Bay, and long-distance (up to 240 km in 89 d). The residence time in Chetumal Bay was higher for females (89.6% of time) than for males (72.0%), but the daily travel rate (0.4–0.5 km/d) was similar for both sexes. Most of the COAs fell within Natural Protected Areas (NPA). However, manatees also travel for long distances into unprotected areas, where they face uncontrolled boat traffic, fishing activities, and habitat loss. Conservation of movement corridors may promote long-distance movements and facilitate genetic exchange.

  10. Species-specific accumulation of polybrominated diphenyl ether flame retardants in birds of prey from the Chesapeake Bay region, USA

    Energy Technology Data Exchange (ETDEWEB)

    Chen Da, E-mail: chen@vims.ed [Department of Environmental and Aquatic Animal Health, Virginia Institute of Marine Science, College of William and Mary, Gloucester Point, VA 23062 (United States); Hale, Robert C. [Department of Environmental and Aquatic Animal Health, Virginia Institute of Marine Science, College of William and Mary, Gloucester Point, VA 23062 (United States); Watts, Bryan D. [Center for Conservation Biology, College of William and Mary, Williamsburg, VA 23185 (United States); La Guardia, Mark J.; Harvey, Ellen [Department of Environmental and Aquatic Animal Health, Virginia Institute of Marine Science, College of William and Mary, Gloucester Point, VA 23062 (United States); Mojica, Elizabeth K. [Center for Conservation Biology, College of William and Mary, Williamsburg, VA 23185 (United States)

    2010-05-15

    Compared to organochlorines, little is known about polybrominated diphenyl ether (PBDE) contamination of birds of prey breeding in the Chesapeake Bay, the largest estuary in the U.S. This study examined and compared PBDE contamination in eggs of osprey, double-crested cormorant, brown pelican and peregrine falcon from this area. Several legacy persistent organic pollutants such as PCBs and DDE were also investigated. The level of urbanization of the landscape appeared to influence the level of PBDE exposure. PBDE congener distribution patterns varied between piscivorous and terrestrial-feeding birds. This suggests individual congeners may be subject to differences in bioaccumulation, biomagnification or metabolism in the aquatic and terrestrial food webs. Biomagnification of PBDEs was studied in the Bay aquatic food chains for the first time. A biomagnification factor of 25.1 was estimated for SIGMAPBDEs for the fish - osprey egg food chain. Hazard quotients, applied as a preliminary evaluation, indicated that PBDEs may pose a moderate hazard to ospreys and peregrine falcons through impairment of reproductive performance. - Birds of prey breeding in the Chesapeake Bay (USA) exhibited species-specific PBDE accumulation patterns.

  11. Species-specific accumulation of polybrominated diphenyl ether flame retardants in birds of prey from the Chesapeake Bay region, USA.

    Science.gov (United States)

    Chen, Da; Hale, Robert C; Watts, Bryan D; La Guardia, Mark J; Harvey, Ellen; Mojica, Elizabeth K

    2010-05-01

    Compared to organochlorines, little is known about polybrominated diphenyl ether (PBDE) contamination of birds of prey breeding in the Chesapeake Bay, the largest estuary in the U.S. This study examined and compared PBDE contamination in eggs of osprey, double-crested cormorant, brown pelican and peregrine falcon from this area. Several legacy persistent organic pollutants such as PCBs and DDE were also investigated. The level of urbanization of the landscape appeared to influence the level of PBDE exposure. PBDE congener distribution patterns varied between piscivorous and terrestrial-feeding birds. This suggests individual congeners may be subject to differences in bioaccumulation, biomagnification or metabolism in the aquatic and terrestrial food webs. Biomagnification of PBDEs was studied in the Bay aquatic food chains for the first time. A biomagnification factor of 25.1 was estimated for SigmaPBDEs for the fish - osprey egg food chain. Hazard quotients, applied as a preliminary evaluation, indicated that PBDEs may pose a moderate hazard to ospreys and peregrine falcons through impairment of reproductive performance. Copyright 2009 Elsevier Ltd. All rights reserved.

  12. Younger Dryas and Holocene oceanography of the western Labrador Sea region based on foraminifera and sediment proxies from Placentia Bay, Newfoundland

    Science.gov (United States)

    Sheldon, Christina; Pearce, Christof; Seidenkrantz, Marit-Solveig; Kuijpers, Antoon; Reynisson, Njáll F.; Zilmer Christensen, Eva; Juncker Hansen, Mette

    2014-05-01

    Benthic foraminiferal assemblages and geochemical analyses from three marine sediment cores from Placentia Bay on the southwest coast of Newfoundland captured the evolving surface and subsurface environment of the eastern Labrador Sea during the late glacial and Holocene. The area, which is today located in the boundary zone between the Arctic Labrador current and the warm Gulf Stream in the eastern margin of the Labrador Sea was during the early part of the Younger Dryas (13.0-12.3 cal. kyr BP) dominated by cold, Arctic conditions and heavy sea-ice cover linked to a strong Polar Water component of the Inner Labrador Current. In the later part of the Younger Dryas (12.3-11.5 kyr BP) the influence of the Labrador Current (LC) became less pronounced resulting in more unstable conditions with varying sea-ice cover and increased influence of Gulf Stream water, presumably linked to an increased strength of the Atlantic Meridional Overturning Circulation (AMOC). The earliest Holocene (11.5-10.4 kyr BP) saw slightly warmer subsurface conditions in Placentia Bay and increased productivity, presumably caused by a decreased southward transport of Polar Water via the LC. The onset of a strong AMOC caused the northward movement of the frontal zone between the Subpolar Gyre and the North Atlantic Subtropical Gyre in the western North Atlantic region to closer proximity to the southern coast of Newfoundland compared to previously. From ca. 10.4-9.65 kyr BP increased bottom-current speeds and the presence of species often found in connection to oceanic fronts, suggest a further strengthening of the AMOC causing inflow of Atlantic-source water into Placentia Bay. This tendency was further strengthened at 9.65-7.3 kyr BP, which saw a relatively strong inflow of Atlantic-source Gulf Stream water into Placentia Bay, evidenced by high frequencies of Cassidulina neoteretis. This inflow of Atlantic was however temporarily halted around 8.2 kyr BP, when a short-lived, extreme peak in

  13. Relationship of land use to water quality in the Chesapeake Bay region. [water sampling and photomapping river basins

    Science.gov (United States)

    Correll, D. L.

    1978-01-01

    Both the proportions of the various land use categories present on each watershed and the specific management practices in use in each category affect the quality of runoff waters, and the water quality of the Bay. Several permanent and portable stations on various Maryland Rivers collect volume-integrated water samples. All samples are analyzed for a series of nutrient, particulate, bacterial, herbicide, and heavy metal parameters. Each basin is mapped with respect to land use by the analysis of low-elevation aerial photos. Analyses are verified and adjusted by ground truth surveys. Data are processed and stored in the Smithsonian Institution data bank. Land use categories being investigated include forests/old fields, pastureland, row crops, residential areas, upland swamps, and tidal marshes.

  14. Projected Commercial Maritime Activity in the Western Arctic

    Science.gov (United States)

    1977-10-01

    Unimak Island 29 10 Minimum Ship Requirements by Arctic Ship Class for Various 35 Ice Control Zones 11 Components of the PVIS Subsystems 49 LIST OF...1978 to 2000 6 Projected Oil Production Regions and When Major Production 21 VBegins 7 March Ice I-formation for Prudhoe Bay to Unimak Island Ship 30...Route September Ice Informetion for Prudhoe Bay to Unimak Island 31 Ship Route 9 Ice Class Designation 36 10 Requirements for Ice Class and Tonnage Size

  15. Linking regional initiatives to improve predictions of drought impacts on living marine resources in the U.S. Southeast: Apalachicola Bay oyster fishery as a potential test case

    Science.gov (United States)

    Petes, L.; McNutt, C.; Burkett, V.; Jones, S.

    2009-12-01

    In 2007, the U.S. Southeast experienced one of the worst droughts on record. Since 1970, moderate-to-severe droughts in the Southeast have increased by 12-14% and annual average temperature has risen over 1°C. Several global climate models also project warming across the Southeast and an increased rate of warming through the end of the century. The Southeast has also undergone unprecedented growth, with some counties of Florida and Georgia populations increasing by over 500% in the last several decades, further increasing the demand for water resources during times of drought. Two regional efforts are currently underway to help inform constituents about adaptation to climate variability and change in the Southeast region. The first effort is the National Integrated Drought Information System (NIDIS), led by NOAA. NIDIS serves as an early warning system for drought through the consolidation of physical/hydrological and socioeconomic impact data, engages those affected by drought, integrates observing networks, and delivers decision-support tools to end-users. The second effort is the USGS’ National Climate Change and Wildlife Science Center, which will facilitate linking global and regional climate models to ecological and biological responses at spatial and temporal resolutions that will inform resource management decisions. Both efforts will be operating in the Apalachicola-Chattahoochee-Flint (ACF) River Basin. During the 2007 drought, one of the most publicized impacts was on the oyster fishery in Apalachicola Bay. Reduced regional precipitation along with associated higher demands for water uses in the ACF reduced downstream flow into the Bay, producing harmful effects on the oyster fishery and associated ecosystem. Changes in estuarine salinity resulting from alterations in streamflow can lead to impacts on species abundance and community composition. Drought can also lead to changes in predator-prey interactions, as marine predators typically move into

  16. The influence of salinity and restoration on wetland soil microbial communities and carbon cycling in the San Francisco Bay-Delta Region

    Science.gov (United States)

    Theroux, S.; Hartman, W.; He, S.; Windham-Myers, L.; Tringe, S. G.

    2014-12-01

    Climate change is predicted to increase the average salinity of the San Francisco Bay-Delta watershed as sea levels rise and alpine snow volume decreases. Wetland soil microbial communities are responsible for cycling greenhouse gases and their response to climate change will heavily influence whether increasing salinity will have a negative or positive effect on the net greenhouse gas budgets of wetlands. To better understand the underlying factors determining the balance of greenhouse gas flux in wetland soils, we targeted the microbial communities along a salinity gradient ranging from freshwater to full seawater in the San Francisco Bay-Delta region. Using DNA and RNA sequencing, coupled with greenhouse gas monitoring, we sampled sixteen sites capturing a range of wetland plant types and restoration states. We determined a suite of soil biogeochemical parameters including moisture, carbon and nutrient contents, pH, sulfate, chloride, and trace metal concentrations. The results of our microbial diversity survey (16S rRNA gene Illumina tag sequencing) showed that salinity and sampling location were the primary drivers of belowground microbial community composition. Freshwater wetland soils, with lower sulfate concentrations, produced more methane than saline sites and we found a parallel increase in the relative abundance of methanogen populations in the high-methane samples. Surprisingly, wetland restoration status did not significantly alter microbial community composition, despite orders of magnitude greater methane flux in restored wetlands compared to reference sites. Deeper metagenomic and metatranscriptomic sequencing in a restored wetland allowed us to further evaluate the roles of methanogen abundance and activity in shaping soil methane production. Our study links belowground microbial communities with their greenhouse gas production, providing a mechanistic microbial framework for assessing climate change feedbacks in wetland soils resulting from sea

  17. Energy-water nexus analysis of enhanced water supply scenarios: a regional comparison of Tampa Bay, Florida, and San Diego, California.

    Science.gov (United States)

    Mo, Weiwei; Wang, Ranran; Zimmerman, Julie B

    2014-05-20

    Increased water demand and scarce freshwater resources have forced communities to seek nontraditional water sources. These challenges are exacerbated in coastal communities, where population growth rates and densities in the United States are the highest. To understand the current management dilemma between constrained surface and groundwater sources and potential new water sources, Tampa Bay, Florida (TB), and San Diego, California (SD), were studied through 2030 accounting for changes in population, water demand, and electricity grid mix. These locations were chosen on the basis of their similar populations, land areas, economies, and water consumption characters as well as their coastal locations and rising contradictions between water demand and supply. Three scenarios were evaluated for each study area: (1) maximization of traditional supplies; (2) maximization of seawater desalination; and (3) maximization of nonpotable water reclamation. Three types of impacts were assessed: embodied energy, greenhouse gas (GHG) emission, and energy cost. SD was found to have higher embodied energy and energy cost but lower GHG emission than TB in most of its water infrastructure systems because of the differences between the electricity grid mixes and water resources of the two regions. Maximizing water reclamation was found to be better than increasing either traditional supplies or seawater desalination in both regions in terms of the three impact categories. The results further imply the importance of assessing the energy-water nexus when pursuing demand-side control targets or goals as well to ensure that the potentially most economical options are considered.

  18. Analysis of Lower Green Bay and Fox River, Collingwood Harbour, Spanish Harbour, and the Metro Toronto and Region remedial action plan (RAP) processes

    Science.gov (United States)

    Gurtner-Zimmermann, Arnold

    1996-07-01

    This article presents a model of remedial action planning, which includes four key variables that determine progress in plan development and implementation and explain the differing level of achievement in individual sites. The model is illustrated by the characteristics and developments of four remedial action plan (RAP) processes (Lower Green Bay and Fox River, Collingwood Harbour, Spanish Harbour, and the Metro Toronto and Region RAPs). Differences in the local context of the plans have, to a significant degree, predisposed individual planning and implementation experiences. Local context includes three variables, namely geographical—technical and sociopolitical aspects and the previous history of water pollution management in the area. RAP precursors are a necessary precondition for progress in planning and substantive achievements. While there is a tendency that most geographically focused RAPs in administratively simple areas accomplish most, the motivation and political clout of RAP participants are strongly intervening factors. Resource input from upper levels of government, in particular financial commitment for plan implementation, is the fourth necessary ingredient for progress due to the RAPs' weak regulatory and institutional framework. Unfortunately, upper levels of government have shown widespread reluctance to lead in remedial action planning. This was only in part offset by local commitment and support for RAP and its cause.

  19. Association of mercury and selenium with altered glutathione metabolism and oxidative stress in diving ducks from the San Francisco Bay region

    Science.gov (United States)

    Hoffman, D.J.; Ohlendorf, H.M.; Marn, C.M.; Pendleton, G.W.

    1998-01-01

    Adult male greater scaup (Aythya marila) (GS), surf scoters (Melanitta perspicillata)(SS), and ruddy ducks (Oxyura jamaicensis) (RD) were collected from Suisun Bay and coastal Tomales Bay in the greater San Francisco Bay area to assess exposure to inorganic contaminants. Hepatic selenium (Se) concentrations were highest in GS (geometric mean = 67 ppm, dw) and SS (119 ppm) in Suisun Bay, whereas hepatic mercury (Hg) was highest (19 ppm) in GS and SS from Tomales Bay. Hepatic Se and Hg were lower in RD and did not differ between locations. Hepatic supernatants were assayed for enzymes related to glutathione metabolism and antioxidant activity including: glucose-6-phosphate dehydrogenase (G-6-PDH), glutathione peroxidase (GSH-peroxidase), glutathione reductase (GSSG-reductase), and glutathione-S-transferase (GSH-transferase). GSH-peroxidase activity was higher in SS and RD, and G-6-PDH higher in GS and SS from Suisun Bay than Tomales Bay. GSSG-reductase was higher in SS from Suisun Bay. The ratio of oxidized glutathione (GSSG) to reduced glutathione (GSH) was greater in all species from Tomales Bay. The following significant relationships were found in one or more species with increasing hepatic Hg concentration: lower body, liver and heart weights; decreased hepatic GSH concentration, G-6-PDH and GSH-peroxidase activities; increased ratio of GSSG to GSH, and increased GSSG-reductase activity. With increasing hepatic Se concentration, GSH-peroxidase increased but GSH decreased. It is concluded that measurement of associated enzymes in conjunction with thiol status may be a useful bioindicator to discriminate between Hg and Se effects. Concentrations of mercury and selenium and variable affected have been associated with adverse effects on reproduction and neurological function in experimental studies with mallards.

  20. From the Bay of Biscay to the High Atlas: completing the anisotropic characterization of the westernmost Mediterranean region.

    Science.gov (United States)

    Diaz, Jordi; Gallart, Josep

    2014-05-01

    The knowledge of the anisotropic properties beneath the Iberian Peninsula and Northern Morocco has been dramatically changed since late 2007 with the analysis of the data provided by the dense TopoIberia-Iberarray broad-band seismic network, the increasing number of permanent stations operating in Morocco, Portugal and Spain and the contribution of smaller scale/higher resolution experiments. The first TopoIberia deployment in the Betics-Alboran zone has evidenced a spectacular rotation of the fast polarization direction (FPD) along the Gibraltar arc following the curvature of the Rif-Betic chain, from roughly N65E beneath the Betics to close to N65W beneath the Rif chain. (Díaz et al, 2010). This result, confirmed latter on by the analysis of the PICASSO experiment data (Miller et al., 2013), has been interpreted as an evidence of mantle flow deflected around the high velocity slab identified by tomographic methods beneath the Gibraltar Arc. Data from the second TopoIberia deployment and from additional deployments in the Moroccan Meseta and the western High Atlas, allowed expanding the investigated area and obtaining a larger scale image of the mantle flow around the region. Diaz et al. (2014) have shown that SW Portugal and the western High Atlas regions have a small degree of anisotropy and a large number of "null" measurements, which suggest the presence of vertical flow in the mantle associated to small-scale edge-driven convective cells. The rather uniform N100ºE FPD retrieved beneath the Variscan Central Iberian Massif is consistent with global mantle flow models taking into account contributions of surface plate motion, density variations and net lithosphere rotation. The last Iberarray deployment covers the northern part of the Iberian Peninsula and has been coeval with the deployment of a similar seismic network in southern France in the framework of the Pyrope project. Even if data from short term experiments in the Pyrenees and northern Iberia have

  1. Assessing the hydrological response from an ensemble of CMIP5 climate projections in the transition zone of the Atlantic region (Bay of Biscay)

    Science.gov (United States)

    Meaurio, Maite; Zabaleta, Ane; Boithias, Laurie; Epelde, Ane Miren; Sauvage, Sabine; Sánchez-Pérez, Jose-Miguel; Srinivasan, Raghavan; Antiguedad, Iñaki

    2017-05-01

    The climate changes projected for the 21st century will have consequences on the hydrological response of catchments. These changes, and their consequences, are most uncertain in the transition zones. The study area, in the Bay of Biscay, is located in the transition zone of the European Atlantic region, where hydrological impact of climate change was scarcely studied. In order to address this scarcity, the hydrological impacts of climate change on river discharge were assessed. To do so, a hydrological modelling was carried out considering 16 climate scenarios that include 5 General Circulation Models (GCM) from the 5th report of the Coupled Model Intercomparison Project (CMIP5), 2 statistical downscaling methods and 2 Representative Concentration Pathways. Projections for future discharge (2011-2100) were divided into three 30-year horizons (2030s, 2060s and 2090s) and a comparison was made between these time horizons and the baseline (1961-2000). The results show that the downscaling method used resulted in a higher source of uncertainty than GCM itself. In addition, the uncertainties inherent to the methods used at all the levels do not affect the results equally along the year. In spite of those uncertainties, general trends for the 2090s predict seasonal discharge decreases by around -17% in autumn, -16% in spring, -11% in winter and -7% in summer. These results are in line with those predicted for the Atlantic region (France and the Iberian Peninsula). Trends for extreme flows were also analysed: the most significant show an increase in the duration (days) of low flows. From an environmental point of view, and considering the need to meet the objectives established by the Water Framework Directive (WFD), this will be a major challenge for the future planning on water management.

  2. USGS Tampa Bay Pilot Study

    Science.gov (United States)

    Yates, K.K.; Cronin, T. M.; Crane, M.; Hansen, M.; Nayeghandi, A.; Swarzenski, P.; Edgar, T.; Brooks, G.R.; Suthard, B.; Hine, A.; Locker, S.; Willard, D.A.; Hastings, D.; Flower, B.; Hollander, D.; Larson, R.A.; Smith, K.

    2007-01-01

    Many of the nation's estuaries have been environmentally stressed since the turn of the 20th century and will continue to be impacted in the future. Tampa Bay, one the Gulf of Mexico's largest estuaries, exemplifies the threats that our estuaries face (EPA Report 2001, Tampa Bay Estuary Program-Comprehensive Conservation and Management Plan (TBEP-CCMP)). More than 2 million people live in the Tampa Bay watershed, and the population constitutes to grow. Demand for freshwater resources, conversion of undeveloped areas to resident and industrial uses, increases in storm-water runoff, and increased air pollution from urban and industrial sources are some of the known human activities that impact Tampa Bay. Beginning on 2001, additional anthropogenic modifications began in Tampa Bat including construction of an underwater gas pipeline and a desalinization plant, expansion of existing ports, and increased freshwater withdrawal from three major tributaries to the bay. In January of 2001, the Tampa Bay Estuary Program (TBEP) and its partners identifies a critical need for participation from the U.S. Geological Survey (USGS) in providing multidisciplinary expertise and a regional-scale, integrated science approach to address complex scientific research issue and critical scientific information gaps that are necessary for continued restoration and preservation of Tampa Bay. Tampa Bay stakeholders identified several critical science gaps for which USGS expertise was needed (Yates et al. 2001). These critical science gaps fall under four topical categories (or system components): 1) water and sediment quality, 2) hydrodynamics, 3) geology and geomorphology, and 4) ecosystem structure and function. Scientists and resource managers participating in Tampa Bay studies recognize that it is no longer sufficient to simply examine each of these estuarine system components individually, Rather, the interrelation among system components must be understood to develop conceptual and

  3. Investigation of Tidal Power, Cobscook Bay, Maine.

    Science.gov (United States)

    1980-08-01

    include Perry, Pembrook, Edmunds, Dennyville, Whiting and Trescott (See Figure 1). Located entirely in the United States at the mouth of the Bay of Fundy ...Quoddy Region because of the softer sediments in that area. Some are harvested within the bay itself, although to a much lesser extent. Lobsters are...earthquake of an intensity VIII occurring in the Bay of Fundy approximately 35 miles west of the site. Closer to the site an earthquake of intensity VII

  4. Epidemiology and potential land-sea transfer of enteric bacteria from terrestrial to marine species in the Monterey Bay Region of California.

    Science.gov (United States)

    Oates, Stori C; Miller, Melissa A; Byrne, Barbara A; Chouicha, Nadira; Hardin, Dane; Jessup, David; Dominik, Clare; Roug, Annette; Schriewer, Alexander; Jang, Spencer S; Miller, Woutrina A

    2012-07-01

    Marine mammals are at risk for infection by fecal-associated zoonotic pathogens when they swim and feed in polluted nearshore marine waters. Because of their tendency to consume 25-30% of their body weight per day in coastal filter-feeding invertebrates, southern sea otters (Enhydra lutris nereis) can act as sentinels of marine ecosystem health in California. Feces from domestic and wildlife species were tested to determine prevalence, potential virulence, and diversity of selected opportunistic enteric bacterial pathogens in the Monterey Bay region. We hypothesized that if sea otters are sentinels of coastal health, and fecal pollution flows from land to sea, then sea otters and terrestrial animals might share the same enteric bacterial species and strains. Twenty-eight percent of fecal samples tested during 2007-2010 were positive for one or more potential pathogens. Campylobacter spp. were isolated most frequently, with an overall prevalence of 11%, followed by Vibrio cholerae (9%), Salmonella spp. (6%), V. parahaemolyticus (5%), and V. alginolyticus (3%). Sea otters were found positive for all target bacteria, exhibiting similar prevalences for Campylobacter and Salmonella spp. but greater prevalences for Vibrio spp. when compared to terrestrial animals. Fifteen Salmonella serotypes were detected, 11 of which were isolated from opossums. This is the first report of sea otter infection by S. enterica Heidelberg, a serotype also associated with human clinical disease. Similar strains of S. enterica Typhimurium were identified in otters, opossums, and gulls, suggesting the possibility of land-sea transfer of enteric bacterial pathogens from terrestrial sources to sea otters.

  5. Organic composition of PM 2.5 and size-segregated aerosols and their sources during the 2002 Bay Regional Atmospheric Chemistry Experiment (BRACE), Florida, USA

    Science.gov (United States)

    Tremblay, Raphaël T.; Riemer, Daniel D.; Zika, Rod G.

    PM 2.5 and size-segregated aerosols were collected in May 2002 as part of the Bay Regional Atmospheric Chemistry Experiment (BRACE), Florida, USA. Aerosol organic composition was used to estimate sources of a series of alkanes and polycyclic aromatic hydrocarbons (PAHs) using chemical indices, hierarchical cluster analysis (HCA) and a chemical mass balance receptor model (CMB). Aerosols were collected on quartz fiber filters (QFF) using a PM 2.5 high volume sampler and on aluminum foil discs using a Micro-Orifice Uniform Deposit Impactor (MOUDI, 50% aerodynamic cut diameters were 18, 10, 5.6, 3.2, 1.8, 1.0, 0.56, 0.315 and 0.171 μm). Target compounds included alkanes and PAHs and were solvent extracted using a mixture of dichloromethane, acetone and hexane, concentrated and then analyzed using a gas chromatograph/mass spectrometer (GC/MS). The target compounds in PM 2.5 were dominated by six sources during the study period: mobile sources (39±5%), coal burning (33±5%), biogenic primary emission (20±2%), oil combustion (5±2%), biomass burning (1.0±0.3%) and an unidentified source (3±2%). Results obtained from the chemical indices, HCA and CMB were in very good agreement with each other. PAH size distributions are presented for days dominated by a same source. Seventy-five percent and 50% of the PAH were found below 1.8 and 0.56 μm, respectively (monthly PAH geometric diameters averaged 0.43 μm). Coarse size PAHs were observed on 1 day (15 May) and were correlated with nitrate and sodium size distribution. It is hypothesized that the PAHs, sodium and nitrate were internally mixed and that the PAHs deposited onto a pre-existing marine aerosol. This transfer process has significant implications for PAH deposition and lifetime and warrants further study.

  6. An examination of historic inorganic sedimentation and organic matter accumulation in several marsh types within the Mobile Bay and and Mobile-Tensaw River Delta region

    Science.gov (United States)

    Smith, Christopher G.; Osterman, Lisa E.; Poore, Richard Z.

    2013-01-01

    Mass accumulation rates (MAR; g cm-2 y-1), linear sedimentation rates (LSR; cm y-1), and core geochronology derived from excess lead-210 (210Pb) profiles and inventories measured in six sediment cores collected from marsh sites from the MobileTensaw River Delta and Mobile Bay region record the importance of both continuous and event-driven inorganic sedimentation over the last 120 years. MAR in freshwater marshes varied considerably between sites and through time (0.24 and 1.31 g cm-2 y-1). The highest MARs occurred in the 1950s and 1960s and correspond to record discharge events along the Mobile and Tensaw Rivers. In comparison, MAR at salt marsh sites increased almost threefold over the last 120 years (0.05 to 0.18 g cm-2 y-1 or 0.23 to 0.48 cm y-1). From 1880 to 1960, organic accumulation remained fairly constant (20%), while intermittent pulses of high inorganic sedimentation were observed following 1960. The pulses in inorganic sedimentation coincide with several major hurricanes (e.g., Hurricanes Camille, Fredric, Georges, and Ivan). The nearly threefold increase in MAR in salt marshes during the last 120 years would thus appear to be partially dependent on inorganic sedimentation from storm events. This study shows that while hurricanes, floods, and other natural hazards are well-known threats to human infrastructure and coastal ecosystems, these events also transport sediment to marshes that help abate other pressures such as sea-level rise (SLR) and subsidence.

  7. Examination of aerosol distributions and radiative effects over the Bay of Bengal and the Arabian Sea region during ICARB using satellite data and a general circulation model

    Directory of Open Access Journals (Sweden)

    R. Cherian

    2012-02-01

    Full Text Available In this paper we analyse aerosol loading and its direct radiative effects over the Bay of Bengal (BoB and Arabian Sea (AS regions for the Integrated Campaign on Aerosols, gases and Radiation Budget (ICARB undertaken during 2006, using satellite data from the MODerate Resolution Imaging Spectroradiometer (MODIS on board the Terra and Aqua satellites, the Aerosol Index from the Ozone Monitoring Instrument (OMI on board the Aura satellite, and the European-Community Hamburg (ECHAM5.5 general circulation model extended by Hamburg Aerosol Module (HAM. By statistically comparing with large-scale satellite data sets, we firstly show that the aerosol properties measured during the ship-based ICARB campaign and simulated by the model are representative for the BoB and AS regions and the pre-monsoon season. In a second step, the modelled aerosol distributions were evaluated by a comparison with the measurements from the ship-based sunphotometer, and the satellite retrievals during ICARB. It is found that the model broadly reproduces the observed spatial and temporal variability in aerosol optical depth (AOD over BoB and AS regions. However, AOD was systematically underestimated during high-pollution episodes, especially in the BoB leg. We show that this underprediction of AOD is mostly because of the deficiencies in the coarse mode, where the model shows that dust is the dominant component. The analysis of dust AOD along with the OMI Aerosol Index indicate that missing dust transport that results from too low dust emission fluxes over the Thar Desert region in the model caused this deficiency. Thirdly, we analysed the spatio-temporal variability of AOD comparing the ship-based observations to the large-scale satellite observations and simulations. It was found that most of the variability along the track was from geographical patterns, with a minor influence by single events. Aerosol fields were homogeneous enough to yield a good statistical agreement

  8. Climatic Atlas of the Outer Continental Shelf Waters and Coastal Regions of Alaska. Volume 3. Chukchi-Beaufort Sea

    Science.gov (United States)

    1988-01-01

    development. Column 8: Number of days entire sea route to Prudhoe Bay less than/equal to five-tenths ice concentration LANDSAT imagery was used to...were -9l%.) PEL ATIVE HUMIDITY %) The observation count for the graph reflects those observations containing both dry and wet bulb temperatures; both...80 40󈧄 20 5203040 eT+ 1 8132 52. 1I 233 25 2 1 4+110+ I - - N w + 1 4 3 3 5.. N 1 + + N + 3 1 + + TOA 1 A3 13 14 5 3 1 + C, A 22 15 20 13 TOA

  9. Computational Approach for Improving Three-Dimensional Sub-Surface Earth Structure for Regional Earthquake Hazard Simulations in the San Francisco Bay Area

    Energy Technology Data Exchange (ETDEWEB)

    Rodgers, A. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-09-25

    In our Exascale Computing Project (ECP) we seek to simulate earthquake ground motions at much higher frequency than is currently possible. Previous simulations in the SFBA were limited to 0.5-1 Hz or lower (Aagaard et al. 2008, 2010), while we have recently simulated the response to 5 Hz. In order to improve confidence in simulated ground motions, we must accurately represent the three-dimensional (3D) sub-surface material properties that govern seismic wave propagation over a broad region. We are currently focusing on the San Francisco Bay Area (SFBA) with a Cartesian domain of size 120 x 80 x 35 km, but this area will be expanded to cover a larger domain. Currently, the United States Geologic Survey (USGS) has a 3D model of the SFBA for seismic simulations. However, this model suffers from two serious shortcomings relative to our application: 1) it does not fit most of the available low frequency (< 1 Hz) seismic waveforms from moderate (magnitude M 3.5-5.0) earthquakes; and 2) it is represented with much lower resolution than necessary for the high frequency simulations (> 5 Hz) we seek to perform. The current model will serve as a starting model for full waveform tomography based on 3D sensitivity kernels. This report serves as the deliverable for our ECP FY2017 Quarter 4 milestone to FY 2018 “Computational approach to developing model updates”. We summarize the current state of 3D seismic simulations in the SFBA and demonstrate the performance of the USGS 3D model for a few selected paths. We show the available open-source waveform data sets for model updates, based on moderate earthquakes recorded in the region. We present a plan for improving the 3D model utilizing the available data and further development of our SW4 application. We project how the model could be improved and present options for further improvements focused on the shallow geotechnical layers using dense passive recordings of ambient and human-induced noise.

  10. A descriptive analysis of the seasonal variation of physical oceanographic characteristics in the northern region of the Todos os Santos Bay (Bahia, Brazil

    Directory of Open Access Journals (Sweden)

    Luiz Bruner de Miranda

    2011-03-01

    Full Text Available The results obtained in the August and December 2003, August 2004 and January 2005 oceanographic campaigns in the northern region of the Todos os Santos Bay (lat. 12º44.5'S; long. 038º35.00'W between the Madre de Deus and Maré islands are analyzed. Instruments of continuous and discrete samplings were used to measure hydrographic properties currents and tides. The water mass of the northern region of the bay is forced by semidiurnal and mesotides of form number 0.08 and the lunar component M2 height was estimated at 91cm. The time series of the surface currents indicated movements in the N/S direction, forced by the tide with maximum magnitudes of 0.73 m.s-1 on the December 2003 campaign. However, in August 2004 the currents were dominated by the wind stress forcing, with a maximum speed of 1.85 m.s-1 and SE direction. Near the bottom, the influence of the tide is not as evident, with a decrease in intensity due to internal and bottom friction, with a maximum velocity of 0.17 m.s-1. The thermal and haline structures were weakly horizontally, as well as vertically stratified, with extreme values varying in the intervals 23ºC (August, 2004 to 28ºC (December, 2003 and 31.0 psu (August, 2003 to 36.0 psu (December, 2003, respectively. Some conclusions may be drawn from these results: i The signs of the dilution of the fresh water discharges of the Caípe, Mataripe and São Paulo rivers in the region under the influence of the RLAM were observed only during the winter periods, but in the summer the region was flooded by waters of oceanic origin and the salinities above 36.0 indicated TW mass intrusion; ii The N-S circulation near the RLAM is strongly dominated by the tide, and the importance of the M2 component was unequivocal, however, the E-W component presented some tidal modulation away from abrupt bottom topographical changes, and iii The residual series, calculated as the difference between the original and modeled, is about ¼ of the

  11. Algae Reefs in Shark Bay, Western Australia, Australia

    Science.gov (United States)

    1990-01-01

    Numerous algae reefs are seen in Shark Bay, Western Australia, Australia (26.0S, 113.5E) especially in the southern portions of the bay. The south end is more saline because tidal flow in and out of the bay is restricted by sediment deposited at the north and central end of the bay opposite the mouth of the Wooramel River. This extremely arid region produces little sediment runoff so that the waters are very clear, saline and rich in algae.

  12. The role of bay breezes and regional transport on a high surface ozone episode during the Houston, Texas DISCOVER-AQ field campaign

    Science.gov (United States)

    Loughner, C.; Follette-Cook, M. B.; Pickering, K. E.; Estes, M. J.

    2014-12-01

    The highest observed surface ozone concentrations in the Houston metropolitan area in 2013 occurred on September 25, which coincided with the Texas DISCOVER-AQ (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality) field campaign. Surface ozone was elevated throughout the Houston metropolitan area. Maximum 8-hour average ozone peaked along the western shore of Galveston Bay, reaching 124 ppbv, almost 50 ppbv above the current EPA standard of 75 ppbv, at La Porte Sylvan Beach. Continental air pollution from the north and northeast was transported into the Houston metropolitan area where it mixed with locally generated emissions. A bay breeze circulation formed causing pollutants that were transported out over the water in the morning to recirculate back inland where they mixed with freshly emitted pollution near the bay breeze convergence zone. The highest surface ozone concentrations were reported near the bay breeze front at La Porte Sylvan Beach. This ozone episode will be presented using measurements made during the DISCOVER-AQ field campaign and WRF and CMAQ model simulations.

  13. HIGH-RESOLUTION ACOUSTIC MAPPING OF GAS CHARGED SEDIMENTS AND LIVING BENTHIC FORAMINIFERA ASSEMBLAGES FROM THE NE REGION OF THE GUANABARA BAY (RJ, BRAZIL

    Directory of Open Access Journals (Sweden)

    Francielli Paula Delavy

    2016-10-01

    Full Text Available This work was performed in the NE region of the Guanabara Bay, a highly impacted Brazilian coastal system, located in Rio de Janeiro State. It aimed to: i identify and map the areas with occurrence of gas in the sediment, as well as its acoustic signature; ii characterize the physical properties of the sediments and; iii document the response of microbenthic organisms (living benthic foraminifera to changes in quantity and quality of organic matter. Seismic surveys at the frequency of 12 kHz identified a large area with about 50% gas charged sediments in the study area. The main acoustic signatures of the shallow gas were black shadow and gas blanket. In addition, features related to gas seepages to the water column (acoustic plumes and pockmarks and gas percolation within the sediments (intra-sedimentary plumes, turbidity pinnacles were also identified. The gas has a biogenic origin and results from the high sedimentation rate between 0.03 to 0.9 cm.year-1 and from the decomposition of large amount of organic matter (10-20%. Vertical distribution of gas ranges from few centimeters to 9 m below the water-sediments interface. These occurrences are related to both gas migration from lower sedimentary layers to Holocene muds above, and to recent generation in near-surface sediments as the area display favorable conditions for gas production. Cores ranging from 150-240 cm in length have predominantly muddy sediments and variations in the P-wave velocity followed the changes in sediment density, controlled mainly by the presence of gas in sediments, bioclasts accumulation, textural variation and percentage of organic matter. The TOC content and Rock-Eval pyrolysis parameters evaluated in nine surface sediment samples indicate that good to excellent amount of organic matter associated with moderate to good source potential for gas production is present in the study area. In these areas living benthic foraminifera are of reduced diversity and density

  14. Near-field receiving water monitoring of trace metals and a benthic community near the Palo Alto Regional Water Quality Control Plant in south San Francisco Bay, California; 2015

    Science.gov (United States)

    Cain, Daniel J.; Thompson, Janet K.; Crauder, Jeffrey; Parchaso, Francis; Stewart, Robin; Turner, Matthew A.; Hornberger, Michelle I.; Luoma, Samuel N.

    2016-07-22

    Trace-metal concentrations in sediment and in the clam Macoma petalum (formerly reported as Macoma balthica), clam reproductive activity, and benthic macroinvertebrate community structure were investigated in a mudflat 1 kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant (PARWQCP) in South San Francisco Bay, California. This report includes data collected by U.S. Geological Survey (USGS) scientists for the period from January 2015 to December 2015. These data are appended to long-term datasets extending back to 1974, and serve as the basis for the City of Palo Alto’s Near-Field Receiving Water Monitoring Program, initiated in 1994.

  15. Near-field receiving water monitoring of trace metals and a benthic community near the Palo Alto Regional Water Quality Control Plant in south San Francisco Bay, California: 2014

    Science.gov (United States)

    Cain, Daniel J.; Thompson, Janet K.; Crauder, Jeff; Parcheso, Francis; Stewart, Robin; Kleckner, Amy E.; Dyke, Jessica; Hornberger, Michelle I.; Luoma, Samuel N.

    2015-01-01

    Trace-metal concentrations in sediment and in the clam Macoma petalum (formerly reported as Macoma balthica), clam reproductive activity, and benthic macroinvertebrate community structure were investigated in a mudflat 1 kilometer (km) south of the discharge of the Palo Alto Regional Water Quality Control Plant (PARWQCP) in South San Francisco Bay, Calif. This report includes the data collected by U.S. Geological Survey (USGS) scientists for the period January 2014 to December 2014. These append to long-term datasets extending back to 1974, and serve as the basis for the City of Palo Alto’s Near-Field Receiving Water Monitoring Program, initiated in 1994. 

  16. Gradient Analysis and Classification of Carolina Bay Vegetation: A Framework for Bay Wetlands Conservation and Restoration

    Energy Technology Data Exchange (ETDEWEB)

    Diane De Steven,Ph.D.; Maureen Tone,PhD.

    1997-10-01

    This report address four project objectives: (1) Gradient model of Carolina bay vegetation on the SRS--The authors use ordination analyses to identify environmental and landscape factors that are correlated with vegetation composition. Significant factors can provide a framework for site-based conservation of existing diversity, and they may also be useful site predictors for potential vegetation in bay restorations. (2) Regional analysis of Carolina bay vegetation diversity--They expand the ordination analyses to assess the degree to which SRS bays encompass the range of vegetation diversity found in the regional landscape of South Carolina's western Upper Coastal Plain. Such comparisons can indicate floristic status relative to regional potentials and identify missing species or community elements that might be re-introduced or restored. (3) Classification of vegetation communities in Upper Coastal Plain bays--They use cluster analysis to identify plant community-types at the regional scale, and explore how this classification may be functional with respect to significant environmental and landscape factors. An environmentally-based classification at the whole-bay level can provide a system of templates for managing bays as individual units and for restoring bays to desired plant communities. (4) Qualitative model for bay vegetation dynamics--They analyze present-day vegetation in relation to historic land uses and disturbances. The distinctive history of SRS bays provides the possibility of assessing pathways of post-disturbance succession. They attempt to develop a coarse-scale model of vegetation shifts in response to changing site factors; such qualitative models can provide a basis for suggesting management interventions that may be needed to maintain desired vegetation in protected or restored bays.

  17. Forward Stagewise Naive Bayes

    OpenAIRE

    Vidaurre Henche, Diego; Bielza, Concha; Larrañaga Múgica, Pedro

    2012-01-01

    The naïve Bayes approach is a simple but often satisfactory method for supervised classification. In this paper, we focus on the naïve Bayes model and propose the application of regularization techniques to learn a naïve Bayes classifier. The main contribution of the paper is a stagewise version of the selective naïve Bayes, which can be considered a regularized version of the naïve Bayes model. We call it forward stagewise naïve Bayes. For comparison’s sake, we also introduce an explicitly r...

  18. A pollution history of Chesapeake Bay

    Science.gov (United States)

    Goldberg, E.D.; Hodge, V.; Koide, M.; Griffin, J.; Gamble, E.; Bricker, O.P.; Matisoff, G.; Holdren, G.R.; Braun, R.

    1978-01-01

    Present day anthropogenic fluxes of some heavy metals to central Chesapeake Bay appear to be intermediate to those of the southern California coastal region and those of Narragansett Bay. The natural fluxes, however, are in general higher. On the bases of Pb-210 and Pu-239 + 240 geochronologies and of the time changes in interstitial water compositions, there is a mixing of the upper 30 or so centimeters of the sediments in the mid-Chesapeake Bay area through bioturbation by burrowing mollusks and polychaetes. Coal, coke and charcoal levels reach one percent or more by dry weight in the deposits, primarily as a consequence of coal mining operations. ?? 1978.

  19. Mitochondrial DNA markers of loggerhead marine turtles (Caretta caretta (Testudines: Cheloniidae nesting at Kyparissia Bay, Greece, confirm the western Greece unit and regional structuring

    Directory of Open Access Journals (Sweden)

    Carlos Carreras

    2014-03-01

    Full Text Available Genetic markers have been widely used in marine turtles to assess population structuring and origin of individuals in common feeding grounds, which are key elements for understanding their ecology and for developing conservation strategies. However, these analyses are very sensitive to missing information, especially from abundant nesting sites. Kyparissia Bay (western Greece hosts the second largest Mediterranean nesting aggregation of the loggerhead turtle (Caretta caretta, but the genetic profile of this nesting site has not, as yet, been described using the extended version of the historically used mitochondrial DNA (mtDNA marker. This marker was genotyped for 36 individuals nesting at Kyparissia Bay and haplotype frequencies obtained were compared with published data from other Mediterranean nesting sites. The results confirmed the connection between Kyparissia and other western Greek nesting sites and the isolation of this western Greek group from other Mediterranean nesting areas. As a consequence of this isolation, this abundant group of nesting aggregations (almost 30% of the Mediterranean stock is not likely to significantly contribute to the recovery of other declining Mediterranean units.

  20. Dietary exposure of PBDEs resulting from a subsistence diet in three First Nation communities in the James Bay Region of Canada.

    Science.gov (United States)

    Liberda, Eric N; Wainman, Bruce C; Leblanc, Alain; Dumas, Pierre; Martin, Ian; Tsuji, Leonard J S

    2011-04-01

    Concerns regarding the persistence, bioaccumulation, long-range transport, and adverse health effects of polybrominated dipheyl ethers (PBDEs) have recently come to light. PBDEs may potentially be of concern to indigenous (First Nations) people of Canada who subsist on traditional foods, but there is a paucity of information on this topic. To investigate whether the traditional diet is a major source of PBDEs in sub-Arctic First Nations populations of the Hudson Bay Lowlands (James and Hudson Bay),Ontario, Canada, a variety of tissues from wild game and fish were analyzed for PBDE content (n=147) and dietary exposure assessed and compared to the US EPA reference doses (RfDs). In addition, to examine the effect of isolation/industrialization on PBDE body burdens, the blood plasma from three First Nations (Cree Nation of Oujé-Bougoumou, Quebec; Fort Albany First Nation, Ontario; and Weenusk First Nation [Peawanuck], Ontario, Canada) were collected (n=54) and analyzed using a log-linear contingency model. The mean values of PBDEs in wild meats and fish adjusted for standard consumption values and body weight, did not exceed the US EPA RfD. Log linear modeling of the human PBDE body burden showed that PBDE body burden increases as access to manufactured goods increases. Thus, household dust from material goods containing PBDEs is likely responsible for the human exposure; the traditional First Nations diet appears to be a minor source of PBDEs. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

  1. Water Use Efficiency Improvement against a Backdrop of Expanding City Agglomeration in Developing Countries—A Case Study on Industrial and Agricultural Water Use in the Bohai Bay Region of China

    Directory of Open Access Journals (Sweden)

    Minghao Bai

    2017-02-01

    Full Text Available Most city agglomerations of developing countries face water shortages and pollution due to population growth and industrial aggregation. To meet such water security challenges, policy makers need to evaluate water use efficiency at the regional or basin level because the prosperity of city agglomerations is indispensable to the sustainable development of the region or basin. To solve the issue, this paper adopts a non-directional distance function within the framework of environmental production technology to measure water use efficiency. Based on the distance between actual water use efficiency and the ideal efficiency, it calculates the potential reduction space of water input and pollutants by slack adjustment. Added to the Malmquist index, it forms a non-radial Malmquist water use performance index, which can be divided into technological change and technical efficiency change, to measure dynamic water use efficiency. Further, water use efficiency change is analyzed from the perspectives of technological improvement and institutional construction. Bohai Bay city agglomeration, a typical water-deficient city agglomeration in China, is taken as a case study, and data on water resource, environment, and economy from 2011 to 2014 have been used. In conclusion, there is much space for water use efficiency improvement on the whole. However, even having considered potential reduction space of water input and pollutant discharge under current environmental production technology, it is still not enough to support the city agglomeration’s sustainable development. To relieve current potential water safety hazards, not only technical improvement but also institution innovation for highly efficient water use should be kept accelerating in Bohai Bay region. In terms of urban water management in developing countries, the research conclusion is of theoretical and practical significance.

  2. Strong variability in bacterioplankton abundance and production in central and western Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Fernandes, V.; Ramaiah, N.; Paul, J.T.; Sardessai, S.; Jyothibabu, R.; Gauns, M.

    to low or no nutrient injections into the surface, primary production in Bay of Bengal is reportedly low. As a consequence, the Bay of Bengal is considered as a region of low biological productivity. Along with many biological parameters, bacterioplankton...

  3. Map showing thickness of young bay mud, southern San Francisco Bay, California

    Science.gov (United States)

    McDonald, Sandra D.; Nichols, Donald R.; Wright, Nancy A.; Atwater, Brian

    1978-01-01

    Soft water-saturated estuarine deposits less than 10,000 years old underlie the southern part of San Francisco bay and the present and former marshlands that border the bay. Known locally as bay mud or as young bay mud, these deposits, and the estuarine environment that produces them, are of major importance in making decision on land use and development in the San Francisco Bay area. Knowledge of the distribution, thickness, and physical properties of young bay mud is critical to the feasibility, design, and maintenance of structures built on it. Fore this reason, numerous attempts have been made in the past to map or describe these characteristics (Mitchell, 1963; Goldman, 1969; McDonald and Nichols, 1974). The accompanying map of bay-mud thickness significantly revises part of an earlier compilation by Kahle and Goldman (1969) and includes new data from approximately 2400 boreholes, most of which have been drilled during the past 15 years. It also incorporates information on historic margins of San Francisco Bay and its tidal marshes (Nichols and Wright, 1971). Although this map was compelled mostly from data gathered during foundation investigations and construction projects, it is mostly from data gathered during foundation investigations and construction projects, it is not a substitute for such studies. Rather, the map provides regional information for land-use planning, seismic zonation, and design of foundation investigations.

  4. Variational Assimilation of Glider Data in Monterey Bay

    Science.gov (United States)

    2011-01-01

    gliders and ten Slocum gliders were deployed in the Monterey Bay region, collecting temperature and salinity profiles (Ramp et al., 2008). Since the... Glider Data in the Monterey Bay 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 0601153N 6. AUTHOR(S) Chudong Pan, Max...observed by gliders in the Monterey Bay in August 2003 are assimilated into NCOM model in the framework of a 3dVar scheme with a hybrid background error

  5. The Evergreen basin and the role of the Silver Creek fault in the San Andreas fault system, San Francisco Bay region, California

    Science.gov (United States)

    Jachens, Robert C.; Wentworth, Carl M.; Graymer, Russell W.; Williams, Robert; Ponce, David A.; Mankinen, Edward A.; Stephenson, William J.; Langenheim, Victoria

    2017-01-01

    The Evergreen basin is a 40-km-long, 8-km-wide Cenozoic sedimentary basin that lies mostly concealed beneath the northeastern margin of the Santa Clara Valley near the south end of San Francisco Bay (California, USA). The basin is bounded on the northeast by the strike-slip Hayward fault and an approximately parallel subsurface fault that is structurally overlain by a set of west-verging reverse-oblique faults which form the present-day southeastward extension of the Hayward fault. It is bounded on the southwest by the Silver Creek fault, a largely dormant or abandoned fault that splays from the active southern Calaveras fault. We propose that the Evergreen basin formed as a strike-slip pull-apart basin in the right step from the Silver Creek fault to the Hayward fault during a time when the Silver Creek fault served as a segment of the main route by which slip was transferred from the central California San Andreas fault to the Hayward and other East Bay faults. The dimensions and shape of the Evergreen basin, together with palinspastic reconstructions of geologic and geophysical features surrounding it, suggest that during its lifetime, the Silver Creek fault transferred a significant portion of the ∼100 km of total offset accommodated by the Hayward fault, and of the 175 km of total San Andreas system offset thought to have been accommodated by the entire East Bay fault system. As shown previously, at ca. 1.5–2.5 Ma the Hayward-Calaveras connection changed from a right-step, releasing regime to a left-step, restraining regime, with the consequent effective abandonment of the Silver Creek fault. This reorganization was, perhaps, preceded by development of the previously proposed basin-bisecting Mount Misery fault, a fault that directly linked the southern end of the Hayward fault with the southern Calaveras fault during extinction of pull-apart activity. Historic seismicity indicates that slip below a depth of 5 km is mostly transferred from the Calaveras

  6. The Pleistocene evolution of the East Antarctic Ice Sheet in the Prydz bay region: Stable isotopic evidence from ODP Site 1167

    Science.gov (United States)

    Theissen, K.M.; Dunbar, R.B.; Cooper, A. K.; Mucciarone, D.A.; Hoffmann, D.

    2003-01-01

    Ocean Drilling Program Leg 188, Prydz Bay, East Antarctica is part of a larger initiative to explore the Cenozoic history of the Antarctic Ice Sheet through direct drilling and sampling of the continental margins. In this paper, we present stable isotopic results from Ocean Drilling Program (ODP) Site 1167 located on the Prydz Channel Trough Mouth Fan (TMF), the first Antarctic TMF to be drilled. The foraminifer-based ??18O record is interpreted along with sedimentary and downhole logging evidence to reconstruct the Quaternary glacial history of Prydz Bay and the adjacent Lambert Glacier Amery Ice Shelf System (LGAISS). We report an electron spin resonance age date of 36. 9 ?? 3.3 ka at 0.45 m below sea floor and correlate suspected glacial-interglacial cycles with the global isotopic stratigraphy to improve the chronology for Site 1167. The ??18O record based on planktonic (Neogloboquadrina pachyderma (s.)) and limited benthic results (Globocassidulina crassa), indicates a trend of ice sheet expansion that was interrupted by a period of reduced ice volume and possibly warmer conditions during the early-mid-Pleistocene (0.9-1.38 Ma). An increase in ?? 18O values after ??? 900 ka appears to coincide with the mid-Pleistocene climate transition and the expansion of the northern hemisphere ice sheet. The ??18O record in the upper 50 m of the stratigraphic section indicates as few as three glacial-interglacial cycles, tentatively assigned as marine isotopic stages (MIS) 16-21, are preserved since the Brunhes/Matuyama paleomagnetic reversal (780 ka). This suggests that there is a large unconformity near the top of the section and/or that there may have been few extreme advances of the ice sheet since the mid-Pleistocene climate transition resulting in lowered sedimentation rates on the Prydz Channel TMF. The stable isotopic record from Site 1167 is one of the few available from the area south of the Antarctic Polar Front that has been linked with the global isotopic

  7. Locally Weighted Naive Bayes

    OpenAIRE

    Frank, Eibe; Hall, Mark; Pfahringer, Bernhard

    2012-01-01

    Despite its simplicity, the naive Bayes classifier has surprised machine learning researchers by exhibiting good performance on a variety of learning problems. Encouraged by these results, researchers have looked to overcome naive Bayes primary weakness - attribute independence - and improve the performance of the algorithm. This paper presents a locally weighted version of naive Bayes that relaxes the independence assumption by learning local models at prediction time. Experimental results s...

  8. Wakasa Bay Weather Forecast Maps

    Data.gov (United States)

    National Aeronautics and Space Administration — The AMSR-E Wakasa Bay Field Campaign was conducted over Wakasa Bay, Japan, in January and February, 2003. The Wakasa Bay Field Campaign includes joint research...

  9. Evaluating local and regional scales of environmental change from sediment characteristics of a tributary of the upper Chesapeake Bay: a geospatial approach to understanding the role of humans on elemental transport and fate

    Science.gov (United States)

    Krahforst, C.; Hartman, S.; Eisen-Cuadra, A.; Bruce, S.; Sherman, L.; Kehm, K.

    2013-12-01

    Most of our coastal systems have experienced changes in ecosystem quality due to increased anthropogenic activities, often resulting in the degradation of water and habitat quality. Estuaries are often the first of marine systems that experience these changes. The distribution of trace elements (V, Cr, Cu, Ni, Pb, As, Sn, Ag, Zn, and Cd) and other sediment characteristics in surface sediments and sediment cores from the Chester River - an estuary located in a predominantly agricultural watershed of the upper Chesapeake Bay, USA - is being determined in order to add to the understanding of contaminant transport and fate and evaluate the likelihood for success of strategies designed to meet or improve the ecological condition of estuaries. The high amount of suspended sediment in the Chester River (10-20 mg L-1) is an important factor controlling water quality conditions and a prime focus for environmental management. Sources of suspended mater and its elemental composition are the result of local runoff, atmospheric deposition, local resuspension, and exchange with the Chesapeake Bay. Preliminary results from multivariate analytic and geospatial mapping analyses of sediment surface grabs display significant covariance with Al for many of the elements investigated which may indicate limited exogenic sources of contamination for of sediments of this watershed. For example total Pb sediment concentrations were mostly below the NOAA's low toxic effects level (94%) and appear to be dominated by crustal weathering or from accelerated soil erosion (Pb vs. Al, r2 = 0.84). These analyses, coupled with sequential leaching of elements from these sediments, sediment organic carbon, activities of selected radionuclides of sediment cores and main stem water quality surveys provide added information of the roles of local land use and region scale processes on ecosystem condition and may direct future management for improving environmental quality of estuaries.

  10. eBay.com

    DEFF Research Database (Denmark)

    Engholm, Ida

    2014-01-01

    Celebrated as one of the leading and most valuable brands in the world, eBay has acquired iconic status on par with century-old brands such as Coca-Cola and Disney. The eBay logo is now synonymous with the world’s leading online auction website, and its design is associated with the company...

  11. Impacts of Watershed Characteristics and Crop Rotations on Winter Cover Crop Nitrate-Nitrogen Uptake Capacity within Agricultural Watersheds in the Chesapeake Bay Region.

    Science.gov (United States)

    Lee, Sangchul; Yeo, In-Young; Sadeghi, Ali M; McCarty, Gregory W; Hively, W Dean; Lang, Megan W

    2016-01-01

    The adoption rate of winter cover crops (WCCs) as an effective conservation management practice to help reduce agricultural nutrient loads in the Chesapeake Bay (CB) is increasing. However, the WCC potential for water quality improvement has not been fully realized at the watershed scale. This study was conducted to evaluate the long-term impact of WCCs on hydrology and NO3-N loads in two adjacent watersheds and to identify key management factors that affect the effectiveness of WCCs using the Soil and Water Assessment Tool (SWAT) and statistical methods. Simulation results indicated that WCCs are effective for reducing NO3-N loads and their performance varied based on planting date, species, soil characteristics, and crop rotations. Early-planted WCCs outperformed late-planted WCCs on the reduction of NO3-N loads and early-planted rye (RE) reduced NO3-N loads by ~49.3% compared to the baseline (no WCC). The WCCs were more effective in a watershed dominated by well-drained soils with increased reductions in NO3-N fluxes of ~2.5 kg N·ha-1 delivered to streams and ~10.1 kg N·ha-1 leached into groundwater compared to poorly-drained soils. Well-drained agricultural lands had higher transport of NO3-N in the soil profile and groundwater due to increased N leaching. Poorly-drained agricultural lands had lower NO3-N due to extensive drainage ditches and anaerobic soil conditions promoting denitrification. The performance of WCCs varied by crop rotations (i.e., continuous corn and corn-soybean), with increased N uptake following soybean crops due to the increased soil mineral N availability by mineralization of soybean residue compared to corn residue. The WCCs can reduce N leaching where baseline NO3-N loads are high in well-drained soils and/or when residual and mineralized N availability is high due to the cropping practices. The findings suggested that WCC implementation plans should be established in watersheds according to local edaphic and agronomic

  12. Impacts of Watershed Characteristics and Crop Rotations on Winter Cover Crop Nitrate-Nitrogen Uptake Capacity within Agricultural Watersheds in the Chesapeake Bay Region

    Science.gov (United States)

    Lee, Sangchul; Yeo, In-Young; Sadeghi, Ali M.; McCarty, Gregory W.; Hively, W. Dean; Lang, Megan W.

    2016-01-01

    The adoption rate of winter cover crops (WCCs) as an effective conservation management practice to help reduce agricultural nutrient loads in the Chesapeake Bay (CB) is increasing. However, the WCC potential for water quality improvement has not been fully realized at the watershed scale. This study was conducted to evaluate the long-term impact of WCCs on hydrology and NO3-N loads in two adjacent watersheds and to identify key management factors that affect the effectiveness of WCCs using the Soil and Water Assessment Tool (SWAT) and statistical methods. Simulation results indicated that WCCs are effective for reducing NO3-N loads and their performance varied based on planting date, species, soil characteristics, and crop rotations. Early-planted WCCs outperformed late-planted WCCs on the reduction of NO3-N loads and early-planted rye (RE) reduced NO3-N loads by ~49.3% compared to the baseline (no WCC). The WCCs were more effective in a watershed dominated by well-drained soils with increased reductions in NO3-N fluxes of ~2.5 kg N·ha-1 delivered to streams and ~10.1 kg N·ha-1 leached into groundwater compared to poorly-drained soils. Well-drained agricultural lands had higher transport of NO3-N in the soil profile and groundwater due to increased N leaching. Poorly-drained agricultural lands had lower NO3-N due to extensive drainage ditches and anaerobic soil conditions promoting denitrification. The performance of WCCs varied by crop rotations (i.e., continuous corn and corn-soybean), with increased N uptake following soybean crops due to the increased soil mineral N availability by mineralization of soybean residue compared to corn residue. The WCCs can reduce N leaching where baseline NO3-N loads are high in well-drained soils and/or when residual and mineralized N availability is high due to the cropping practices. The findings suggested that WCC implementation plans should be established in watersheds according to local edaphic and agronomic

  13. Geoid and gravity anomaly data of conjugate regions of Bay of Bengal and Enderby Basin: New constraints on breakup and early spreading history between India and Antarctica

    Digital Repository Service at National Institute of Oceanography (India)

    Krishna, K.S.; Michael, L.; Bhattacharyya, R.; Majumdar, T.J.

    the rifting process in the north between combined north ECMI-Elan Bank and MacRobertson Land and in the south between southwest Sri Lanka and Gunnerus Ridge region of East Antarctica. Approximately during the period between the anomalies M1 and M0 and soon...

  14. Control of hardwood regeneration in restored carolina bay depression wetlands.

    Energy Technology Data Exchange (ETDEWEB)

    Moser, Lee, J.; Barton, Christopher, D.; Blake, John, I.

    2012-06-01

    Carolina bays are depression wetlands located in the coastal plain region of the eastern United States. Disturbance of this wetland type has been widespread, and many sites contain one or more drainage ditches. Restoration of bays is of interest because they are important habitats for rare flora and fauna. Previous bay restoration projects have identified flood-tolerant woody competitors in the seedbank and re-sprouting as impediments to the establishment of desired herbaceous wetland vegetation communities. We restored 3 bays on the Savannah River Site, South Carolina, by plugging drainage ditches, harvesting residual pine/hardwood stands within the bays, and monitoring the vegetative response of the seedbank to the hydrologic change. We applied a foliar herbicide on one-half of each bay to control red maple (Acerrubrum), sweetgum (Liquidambar styraciflua), and water oak (Quercus nigra) sprouting, and we tested its effectiveness across a hydrologic gradient in each bay. Hardwood regeneration was partially controlled by flooding in bays that exhibited long growing season hydroperiods. The findings also indicated that herbicide application was an effective means for managing hardwood regeneration and re-sprouting in areas where hydrologic control was ineffective. Herbicide use had no effect on species richness in the emerging vegetation community. In late-season drawdown periods, or in bays where hydroperiods are short, more than one herbicide application may be necessary.

  15. Integrating naive Bayes and FOIL

    OpenAIRE

    Landwehr, Niels; Kersting, Kristian; De Raedt, Luc

    2007-01-01

    A novel relational learning approach that tightly integrates the naive Bayes learning scheme with the inductive logic programming rule-learner FOIL is presented. In contrast to previous combinations that have employed naive Bayes only for post-processing the rule sets, the presented approach employs the naive Bayes criterion to guide its search directly. The proposed technique is implemented in the NFOIL and TFOIL systems, which employ standard naive Bayes and tree augmented naive Bayes model...

  16. Climatic characterization of the Banderas Bay Region using Köppen’s system modified by García and Geographic Information Systems techniques

    OpenAIRE

    Antonio Velázquez Ruiz; Luis Manuel Martínez R.; Fátima Maciel Carrillo González

    2012-01-01

    The identification of different climatic zones can be an important factor for decision-makers in various fields such as urban planning and agricultural alternatives. In order to characterize the climates of the region of Bahía de Banderas (BB) Mexico, we adopted a methodology that combines the use of the Köppen climate classification modified by Garc.a for Mexico and methods of Geographic Information Systems (GIS). We used simple regression between temperature (dependent variable) and height ...

  17. Isopachs--Salt Point to Drakes Bay, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the sediment-thickness map of the Salt Point to Drakes Bay, California, region. The raster data file is included in...

  18. Tampa Bay Topographic/Bathymetric Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In this joint demonstration project for the Tampa Bay region, NOAA's National Ocean Service (NOS) and the U.S. Geological Survey (USGS) have merged NOAA bathymetric...

  19. Species List for Back Bay National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a species list of fish, mammals, amphibians, and reptiles that are either common to the Back Bay area or have ranges that extend into this region. This list...

  20. Distribution of nutrients in the western Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    DeSousa, S.N.; Naqvi, S.W.A.; Reddy, C.V.G.

    Distribution of phosphates and nitrates in relation to some physico-chemical features of the western Bay of Bengal during August-September 1976 indicated marked regional variations. The mixed surface layer which was associated with high oxygen...

  1. Hammond Bay Biological Station

    Data.gov (United States)

    Federal Laboratory Consortium — Hammond Bay Biological Station (HBBS), located near Millersburg, Michigan, is a field station of the USGS Great Lakes Science Center (GLSC). HBBS was established by...

  2. Humboldt Bay Orthoimages

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set consists of 0.5-meter pixel resolution, four band orthoimages covering the Humboldt Bay area. An orthoimage is remotely sensed image data in which...

  3. Biscayne Bay Alongshore Epifauna

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Field studies to characterize the alongshore epifauna (shrimp, crabs, echinoderms, and small fishes) along the western shore of southern Biscayne Bay were started in...

  4. Climatic characterization of the Banderas Bay Region using Köppen’s system modified by García and Geographic Information Systems techniques

    Directory of Open Access Journals (Sweden)

    Antonio Velázquez Ruiz

    2012-11-01

    Full Text Available The identification of different climatic zones can be an important factor for decision-makers in various fields such as urban planning and agricultural alternatives. In order to characterize the climates of the region of Bahía de Banderas (BB Mexico, we adopted a methodology that combines the use of the Köppen climate classification modified by Garc.a for Mexico and methods of Geographic Information Systems (GIS. We used simple regression between temperature (dependent variable and height as independent variable. Multiple regressions were applied for rainfall (dependent variable and geographical data as independent variables (thermal continentality, thermopluviometric index and slope. The temperature and precipitation data were obtained from the Comisión Nacional del Agua, and ERIC III, 2006 database. Information from geographical variables was obtained from a Digital Elevation Model and Gorzynski’s Index of Continentality. The coefficients of simple and multiple regressions were used to construct digital maps of annual temperature and precipitation via GIS. With these maps and using the CCK-EG tool, we generated the final map of climatic characterization. The result was highly representative. The determination coefficients were 0.82 and 0.39 for temperature and precipitation respectively. The resulting classification for each of the stations was located in their corresponding climate zone on the final map. Zones and climatic limits were identified for this study region.

  5. Analysis of clay smoking pipes from archeological sites in the region of the Guanabara Bay (Rio de Janeiro, Brazil) by FT-IR

    Science.gov (United States)

    Freitas, Renato P.; Ribeiro, Iohanna M.; Calza, Cristiane; Oliveira, Ana L.; Silva, Mariane L.; Felix, Valter S.; Ferreira, Douglas S.; Coelho, Felipe A.; Gaspar, Maria D.; Pimenta, André R.; Medeiros, Elanio A.; Lopes, Ricardo T.

    2016-06-01

    In this study, twenty samples of clay smoking pipes excavated in an 18 km2 area between the Macacu and Caceribu rivers, in the municipality of Itaboraí, Rio de Janeiro, Brazil were analyzed by FT-IR technique. The samples, excavated in different archeological sites of the region, are dated between the seventeenth and the nineteenth centuries and are part of the material culture left by Africans and African descendants that lived in the complex. FT-IR analyses and complementary SEM-EDS studies showed that the clay paste used in the manufacture of smoking pipes, mostly handcrafted, is composed of quartz, feldspar, phyllosilicates and iron oxides. Multivariate statistical tests (PCA) were applied to FT-IR data to assess the interactions between the archeological sites. The results indicated that one archeological site - Macacu IV - is greatly related to the other sites. The results obtained have helped archeologists and anthropologists in better understanding the manufacturing process employed in ancient ceramic artifacts produced during the period of colonial Brazil.

  6. Near-field receiving water monitoring of trace metals and a benthic community near the Palo Alto Regional Water Quality Control Plant in south San Francisco Bay, California; 2016

    Science.gov (United States)

    Cain, Daniel J.; Thompson, Janet K.; Parchaso, Francis; Pearson, Sarah; Stewart, Robin; Turner, Mathew; Barasch, David; Luoma, Samuel N.

    2017-10-30

    Trace-metal concentrations in sediment and in the clam Macoma petalum (formerly reported as Macoma balthica), clam reproductive activity, and benthic macroinvertebrate community structure were investigated in a mudflat 1 kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant (PARWQCP) in south San Francisco Bay, Calif. This report includes the data collected by U.S. Geological Survey (USGS) scientists for the period January 2014 to December 2016. These append to long-term datasets extending back to 1974. A major focus of the report is an integrated description of the 2016 data within the context of the longer, multi-decadal dataset. This dataset supports the City of Palo Alto’s Near-Field Receiving Water Monitoring Program, initiated in 1994.Significant reductions in silver and copper concentrations in sediment and M. petalum occurred at the site in the 1980s following the implementation by PARWQCP of advanced wastewater treatment and source control measures. Since the 1990s, concentrations of these elements appear to have stabilized at concentrations somewhat above (silver) or near (copper) regional background concentrations Data for other metals, including chromium (Cr), mercury (Hg), nickel (Ni), selenium (Se), and zinc (Zn), have been collected since 1994. Over this period, concentrations of these elements have remained relatively constant, aside from seasonal variation that is common to all elements. In 2016, concentrations of silver and copper in M. petalum varied seasonally in response to a combination of site-specific metal exposures and annual growth and reproduction, as reported previously. Seasonal patterns for other elements, including Cr, Ni, Zn, Hg, and Se, were generally similar in timing and magnitude as those for Ag and Cu. This record suggests that legacy contamination and regional-scale factors now largely control sedimentary and bioavailable concentrations of silver and copper, as well as other elements of

  7. Bay breeze climatology at two sites along the Chesapeake bay from 1986-2010: Implications for surface ozone.

    Science.gov (United States)

    Stauffer, Ryan M; Thompson, Anne M

    Hourly surface meteorological measurements were coupled with surface ozone (O3) mixing ratio measurements at Hampton, Virginia and Baltimore, Maryland, two sites along the Chesapeake Bay in the Mid-Atlantic United States, to examine the behavior of surface O3 during bay breeze events and quantify the impact of the bay breeze on local O3 pollution. Analyses were performed for the months of May through September for the years 1986 to 2010. The years were split into three groups to account for increasingly stringent environmental regulations that reduced regional emissions of nitrogen oxides (NOx): 1986-1994, 1995-2002, and 2003-2010. Each day in the 25-year record was marked either as a bay breeze day, a non-bay breeze day, or a rainy/cloudy day based on the meteorological data. Mean eight hour (8-h) averaged surface O3 values during bay breeze events were 3 to 5 parts per billion by volume (ppbv) higher at Hampton and Baltimore than on non-bay breeze days in all year periods. Anomalies from mean surface O3 were highest in the afternoon at both sites during bay breeze days in the 2003-2010 study period. In conjunction with an overall lowering of baseline O3 after the 1995-2002 period, the percentage of total exceedances of the Environmental Protection Agency (EPA) 75 ppbv 8-h O3 standard that occurred on bay breeze days increased at Hampton for 2003-2010, while remaining steady at Baltimore. These results suggest that bay breeze circulations are becoming more important to causing exceedance events at particular sites in the region, and support the hypothesis of Martins et al. (2012) that highly localized meteorology increasingly drives air quality events at Hampton.

  8. Bayes and the Law.

    Science.gov (United States)

    Fenton, Norman; Neil, Martin; Berger, Daniel

    2016-06-01

    Although the last forty years has seen considerable growth in the use of statistics in legal proceedings, it is primarily classical statistical methods rather than Bayesian methods that have been used. Yet the Bayesian approach avoids many of the problems of classical statistics and is also well suited to a broader range of problems. This paper reviews the potential and actual use of Bayes in the law and explains the main reasons for its lack of impact on legal practice. These include misconceptions by the legal community about Bayes' theorem, over-reliance on the use of the likelihood ratio and the lack of adoption of modern computational methods. We argue that Bayesian Networks (BNs), which automatically produce the necessary Bayesian calculations, provide an opportunity to address most concerns about using Bayes in the law.

  9. Integrating science and resource management in Tampa Bay, Florida

    Science.gov (United States)

    Yates, Kimberly K.; Greening, Holly; Morrison, Gerold

    2011-01-01

    Tampa Bay is recognized internationally for its remarkable progress towards recovery since it was pronounced "dead" in the late 1970s. Due to significant efforts by local governments, industries and private citizens throughout the watershed, water clarity in Tampa Bay is now equal to what it was in 1950, when population in the watershed was less than one-quarter of what it is today. Seagrass extent has increased by more than 8,000 acres since the mid-1980s, and fish and wildlife populations are increasing. Central to this successful turn-around has been the Tampa Bay resource management community's long-term commitment to development and implementation of strong science-based management strategies. Research institutions and agencies, including Eckerd College, the Florida Wildlife Commission Fish and Wildlife Research Institute, Mote Marine Laboratory, National Oceanic and Atmospheric Administration, the Southwest Florida Water Management District, University of South Florida, U.S. Environmental Protection Agency, U.S. Geological Survey, local and State governments, and private companies contribute significantly to the scientific basis of our understanding of Tampa Bay's structure and ecological function. Resource management agencies, including the Tampa Bay Regional Planning Council's Agency on Bay Management, the Southwest Florida Water Management District's Surface Water Improvement and Management Program, and the Tampa Bay Estuary Program, depend upon this scientific basis to develop and implement regional adaptive management programs. The importance of integrating science with management has become fully recognized by scientists and managers throughout the region, State and Nation. Scientific studies conducted in Tampa Bay over the past 10–15 years are increasingly diverse and complex, and resource management programs reflect our increased knowledge of geology, hydrology and hydrodynamics, ecology and restoration techniques. However, a synthesis of this

  10. Evolving extended naive Bayes classifiers

    OpenAIRE

    Klawonn, Frank; Angelov, Plamen

    2006-01-01

    Naive Bayes classifiers are a very simple, but often effective tool for classification problems, although they are based on independence assumptions that do not hold in most cases. Extended naive Bayes classifiers also rely on independence assumptions, but break them down to artificial subclasses, in this way becoming more powerful than ordinary naive Bayes classifiers. Since the involved computations for Bayes classifiers are basically generalised mean value calculations, they easily render ...

  11. Mapping Oyster Reef Habitats in Mobile Bay

    Science.gov (United States)

    Bolte, Danielle

    2011-01-01

    habitats in the southeastern regions of the Bay.

  12. Lost lake - restoration of a Carolina bay

    Energy Technology Data Exchange (ETDEWEB)

    Hanlin, H.G.; McLendon, J.P. [Univ. of South Carolina, Aiken, SC (United States). Dept. of Biology and Geology; Wike, L.D. [Univ. of South Carolina, Aiken, SC (United States). Dept. of Biology and Geology]|[Westinghouse Savannah River Co., Aiken, SC (United States). Savannah River Technology Center; Dietsch, B.M. [Univ. of South Carolina, Aiken, SC (United States). Dept. of Biology and Geology]|[Univ. of Georgia, Aiken, SC (United States)

    1994-09-01

    Carolina bays are shallow wetland depressions found only on the Atlantic Coastal Plain. Although these isolated interstream wetlands support many types of communities, they share the common features of having a sandy margin, a fluctuating water level, an elliptical shape, and a northwest to southeast orientation. Lost Lake, an 11.3 hectare Carolina bay, was ditched and drained for agricultural production before establishment of the Savannah River Site in 1950. Later it received overflow from a seepage basin containing a variety of chemicals, primarily solvents and some heavy metals. In 1990 a plan was developed for the restoration of Lost Lake, and restoration activities were complete by mid-1991. Lost Lake is the first known project designed for the restoration and recovery of a Carolina bay. The bay was divided into eight soil treatment zones, allowing four treatments in duplicate. Each of the eight zones was planted with eight species of native wetland plants. Recolonization of the bay by amphibians and reptiles is being evaluated by using drift fences with pitfall traps and coverboard arrays in each of the treatment zones. Additional drift fences in five upland habitats were also established. Hoop turtle traps, funnel minnow traps, and dip nets were utilized for aquatic sampling. The presence of 43 species common to the region has been documented at Lost Lake. More than one-third of these species show evidence of breeding populations being established. Three species found prior to the restoration activity and a number of species common to undisturbed Carolina bays were not encountered. Colonization by additional species is anticipated as the wetland undergoes further succession.

  13. Gateway National Recreation Area, Jamaica Bay Unit : Jamaica Bay Greenway Missing Links Study.

    Science.gov (United States)

    2010-09-24

    Based on both a field site reconnaissance and workshop, this study developed a conceptual plan for the location and design of bicyle facilites to complete a "missing link" of the Jamaica Bay through the Rockaway region of Brooklyn and Queens in New Y...

  14. Development of an integrated ecosystem model to determine effectiveness of potential watershed management projects on improving Old Tampa Bay

    Science.gov (United States)

    Edward T. Sherwood; Holly Greening; Lizanne Garcia; Kris Kaufman; Tony Janicki; Ray Pribble; Brett Cunningham; Steve Peene; Jim Fitzpatrick; Kellie Dixon; Mike Wessel

    2016-01-01

    The Tampa Bay estuary has undergone a remarkable ecosystem recovery since the 1980s despite continued population growth within the region. However during this time, the Old Tampa Bay (OTB) segment has lagged behind the rest of the Bay’s recovery relative to improvements in overall water quality and seagrass coverage. In 2011, the Tampa Bay Estuary Program, in...

  15. Down by the Bay

    Science.gov (United States)

    Allison, Elizabeth; Tunks, Karyn; Hardman, Kacie

    2017-01-01

    The Pelican's Nest, located near Mobile Bay in the Gulf of Mexico, is a science center supported by a local educational foundation. Programs are geared toward marine wildlife and the coastal habitat with an emphasis on hands-on learning for students in grades K-6. The director of the science center conducts daily classroom labs and discovery trips…

  16. An Oceanographic and Climatological Atlas of Bristol Bay

    Science.gov (United States)

    1987-10-01

    have a profound the bay North Pacific water which has just entered effect on regional oceanographic phenomena. An the Bering Sea through Unimak Pass... Unimak circulation in outer Bristol Bay consists of a Island, much of the coastal current is entrained typically unclosed counterclockwise gyre open to...Peninsula and become more face currents. cyclonic and rotary offshore. National Ocean Sea level changes on either side of Unimak Survey current tables

  17. Hierarchical Naive Bayes for genetic association studies.

    Science.gov (United States)

    Malovini, Alberto; Barbarini, Nicola; Bellazzi, Riccardo; de Michelis, Francesca

    2012-01-01

    Genome Wide Association Studies represent powerful approaches that aim at disentangling the genetic and molecular mechanisms underlying complex traits. The usual "one-SNP-at-the-time" testing strategy cannot capture the multi-factorial nature of this kind of disorders. We propose a Hierarchical Naïve Bayes classification model for taking into account associations in SNPs data characterized by Linkage Disequilibrium. Validation shows that our model reaches classification performances superior to those obtained by the standard Naïve Bayes classifier for simulated and real datasets. In the Hierarchical Naïve Bayes implemented, the SNPs mapping to the same region of Linkage Disequilibrium are considered as "details" or "replicates" of the locus, each contributing to the overall effect of the region on the phenotype. A latent variable for each block, which models the "population" of correlated SNPs, can be then used to summarize the available information. The classification is thus performed relying on the latent variables conditional probability distributions and on the SNPs data available. The developed methodology has been tested on simulated datasets, each composed by 300 cases, 300 controls and a variable number of SNPs. Our approach has been also applied to two real datasets on the genetic bases of Type 1 Diabetes and Type 2 Diabetes generated by the Wellcome Trust Case Control Consortium. The approach proposed in this paper, called Hierarchical Naïve Bayes, allows dealing with classification of examples for which genetic information of structurally correlated SNPs are available. It improves the Naïve Bayes performances by properly handling the within-loci variability.

  18. Chesapeake Bay Program Water Quality Database

    Science.gov (United States)

    The Chesapeake Information Management System (CIMS), designed in 1996, is an integrated, accessible information management system for the Chesapeake Bay Region. CIMS is an organized, distributed library of information and software tools designed to increase basin-wide public access to Chesapeake Bay information. The information delivered by CIMS includes technical and public information, educational material, environmental indicators, policy documents, and scientific data. Through the use of relational databases, web-based programming, and web-based GIS a large number of Internet resources have been established. These resources include multiple distributed on-line databases, on-demand graphing and mapping of environmental data, and geographic searching tools for environmental information. Baseline monitoring data, summarized data and environmental indicators that document ecosystem status and trends, confirm linkages between water quality, habitat quality and abundance, and the distribution and integrity of biological populations are also available. One of the major features of the CIMS network is the Chesapeake Bay Program's Data Hub, providing users access to a suite of long- term water quality and living resources databases. Chesapeake Bay mainstem and tidal tributary water quality, benthic macroinvertebrates, toxics, plankton, and fluorescence data can be obtained for a network of over 800 monitoring stations.

  19. Preparing Informal Bay Area Educators for Climate Education Success

    Science.gov (United States)

    Romero, M.

    2016-12-01

    The Bay Area Climate Literacy Impact Collaborative (Bay-CLIC) joins informal science educators from over 30 environmental education organizations with the common goal of increasing climate literacy and action. Over this past year, the collaborative has been gathering existing tools and resources that will allow informal educators in the Bay Area to communicate on climate change with confidence. Bay-CLIC's work plans to bring climate science to life by equipping educators with climate data that resonates best with local audiences, which is data that is place-based and personal. Bay-CLIC is also researching effective sustainability campaigns focused on behavior change that can be crafted to fit our unique regional context and rolled out across multiple Bay-CLIC member organizations. This session will focus on sharing our findings from our six month information gathering phase. The overarching discussion will focus on the needs that Bay Area educators identified as necessary to address in order for them to provide the best quality climate education programming. We will also discuss the data we gathered on what local educators are already using in their work and share out on how this diverse array of informal educators will be implementing our research into their programs.

  20. Richards Bay effluent pipeline

    CSIR Research Space (South Africa)

    Lord, DA

    1986-07-01

    Full Text Available 3815 9 D A Lord Department of Oceanography University of Port Elizabeth P 0 Box 1600 PORT ELIZABETH 6000 N D Geldenhuys Department of Environment Affairs Private Bag X9005 CAPE TOWN 8000 Cover: Richards Bay from the air showing city... of major concern identified in the effluent are the large volume of byproduct calcium sulphate (phosphogypsum) which would smother marine life, high concentrations of fluoride highly toxic to marine life, heavy metals, chlorinated organic material...

  1. 78 FR 27989 - Bandon Marsh, Nestucca Bay, and Siletz Bay National Wildlife Refuges, Coos, Tillamook, and...

    Science.gov (United States)

    2013-05-13

    ... Fish and Wildlife Service Bandon Marsh, Nestucca Bay, and Siletz Bay National Wildlife Refuges, Coos... Assessments (EAs) for three Oregon refuges--Bandon Marsh, Nestucca Bay, and Siletz Bay National Wildlife... ``Bandon Marsh, Nestucca Bay, and Siletz Bay final CCPs and FONSIs'' in the subject line of the message. U...

  2. 75 FR 73121 - Bandon Marsh, Nestucca Bay, and Siletz Bay National Wildlife Refuges, Coos, Tillamook, and...

    Science.gov (United States)

    2010-11-29

    ... Fish and Wildlife Service Bandon Marsh, Nestucca Bay, and Siletz Bay National Wildlife Refuges, Coos... prepare a comprehensive conservation plan (CCP) for the Bandon Marsh, Nestucca Bay, and Siletz Bay... ``Bandon Marsh, Nestucca Bay, and Siletz Bay CCP'' in the subject line of the message. Fax: Attn: Project...

  3. Near-field receiving water monitoring of trace metals and a benthic community near the Palo Alto Regional Water Quality Control Plant in South San Francisco Bay, California: 2013

    Science.gov (United States)

    Dyke, Jessica; Cain, Daniel J.; Thompson, Janet K.; Kleckner, Amy E.; Parcheso, Francis; Hornberger, Michelle I.; Luoma, Samuel N.

    2014-01-01

    Trace-metal concentrations in sediment and in the clam Macoma petalum (formerly reported as Macoma balthica), clam reproductive activity, and benthic macroinvertebrate community structure were investigated in a mudflat 1 kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant (PARWQCP) in South San Francisco Bay, Calif. This report includes the data collected by U.S. Geological Survey (USGS) scientists for the period January 2013 to December 2013. These data serve as the basis for the City of Palo Alto’s Near-Field Receiving Water Monitoring Program, initiated in 1994. Following significant reductions in the late 1980s, silver (Ag) and copper (Cu) concentrations in sediment and M. petalum appear to have stabilized. Data for other metals, including chromium (Cr), mercury (Hg), nickel (Ni), selenium (Se), and zinc (Zn), have been collected since 1994. Over this period, concentrations of these elements have remained relatively constant, aside from seasonal variation that is common to all elements. In 2013, concentrations of Ag and Cu in M. petalum varied seasonally in response to a combination of site-specific metal exposures and annual growth and reproduction, as reported previously. Seasonal patterns for other elements, including Cr, Ni, Zn, Hg, and Se, were generally similar in timing and magnitude as those for Ag and Cu. In M. petalum, all observed elements showed annual maxima in January–February and minima in April, except for Zn, which was lowest in December. In sediments, annual maxima also occurred in January–February, and minima were measured in June and September. In 2013, metal concentrations in both sediments and clam tissue were among the lowest concentrations on record. This record suggests that regional-scale factors now largely control sedimentary and bioavailable concentrations of Ag and Cu, as well as other elements of regulatory interest, at the Palo Alto site. Analyses of the benthic community structure of a

  4. Near-field receiving water monitoring of trace metals and a benthic community near the Palo Alto Regional Water Quality Control Plant in south San Francisco Bay, California, 2012

    Science.gov (United States)

    Dyke, Jessica; Thompson, Janet K.; Cain, Daniel J.; Kleckner, Amy E.; Parcheso, Francis; Luoma, Samuel N.; Hornberger, Michelle I.

    2013-01-01

    Trace-metal concentrations in sediment and in the clam Macoma petalum (formerly reported as Macoma balthica), clam reproductive activity, and benthic macroinvertebrate community structure were investigated in a mudflat 1 kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant (PARWQCP) in South San Francisco Bay, Calif. This report includes the data collected by U.S. Geological Survey (USGS) scientists for the period January to December 2012. These data serve as the basis for the City of Palo Alto’s Near-Field Receiving Water Monitoring Program, initiated in 1994. Following significant reductions in the late 1980s, silver (Ag) and copper (Cu) concentrations in sediment and in M. petalum appear to have stabilized. Data for other metals, including chromium (Cr), mercury (Hg), nickel (Ni), selenium (Se), and zinc (Zn), have been collected since 1994. Over this period, concentrations of these elements have remained relatively constant, aside from seasonal variation that is common to all elements. In 2012, concentrations of Ag and Cu in M. petalum varied seasonally in response to a combination of site-specific metal exposures and annual growth and reproduction, as reported for previous time periods. Seasonal patterns for other elements, including Cr, Ni, Zn, Hg, and Se were generally similar in timing and magnitude as those for Ag and Cu. In 2012, metal concentrations in both sediments and clam tissue were among the lowest concentrations on record. This record suggests that regional-scale factors now largely control sedimentary and bioavailable concentrations of Ag and Cu, as well as other elements of regulatory interest, at the Palo Alto site. Analyses of the benthic community structure of a mudflat in South San Francisco Bay over a 39-year period show that changes in the community have occurred concurrent with reduced concentrations of metals in the sediment and in the tissues of the biosentinel clam, M. petalum, from the same area

  5. Near-field receiving water monitoring of trace metals and a benthic community near the Palo Alto Regional Water Quality Control Plant in south San Francisco Bay, California: 2011

    Science.gov (United States)

    Dyke, Jessica; Thompson, Janet K.; Cain, Daniel J.; Kleckner, Amy E.; Parcheso, Francis; Luoma, Samuel N.; Hornberger, Michelle I.

    2012-01-01

    Trace-metal concentrations in sediment and in the clam Macoma petalum (formerly reported as Macoma balthica), clam reproductive activity, and benthic macroinvertebrate community structure were investigated in a mudflat 1 kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant (PARWQCP) in South San Francisco Bay, Calif. This report includes the data collected by U.S. Geological Survey (USGS) scientists for the period January 2011 to December 2011. These data serve as the basis for the City of Palo Alto's Near-Field Receiving Water Monitoring Program, initiated in 1994. Following significant reductions in the late 1980s, silver (Ag) and copper (Cu) concentrations in sediment and M. petalum appear to have stabilized. Data for other metals, including chromium, mercury, nickel, selenium, and zinc, have been collected since 1994. Over this period, concentrations of these elements have remained relatively constant, aside from seasonal variation that is common to all elements. In 2011, concentrations of Ag and Cu in M. petalum varied seasonally in response to a combination of site-specific metal exposures and annual growth and reproduction, as reported previously. Seasonal patterns for other elements, including Cr, Hg, Ni, Se, and Zn, were generally similar in timing and magnitude as those for Ag and Cu. In 2011, metal concentrations in both sediments and clam tissue were among the lowest concentrations on record. This record suggests that regional-scale factors now largely control sedimentary and bioavailable concentrations of Ag and Cu, as well as other elements of regulatory interest, at the Palo Alto site. Analyses of the benthic community structure of a mudflat in South San Francisco Bay over a 38-year period show that changes in the community have occurred concurrent with reduced concentrations of metals in the sediment and in the tissues of the biosentinel clam, M. petalum, from the same area. Analysis of the M. petalum community

  6. BCDC Bay Trail Alignment 2009

    Data.gov (United States)

    California Department of Resources — The Bay Trail provides easily accessible recreational opportunities for outdoor enthusiasts, including hikers, joggers, bicyclists and skaters. It also offers a...

  7. Bay of Bengal Surface and Thermocline and the Arabian Sea

    Science.gov (United States)

    2015-09-30

    belt, including their seasonal and interannual variability and the impact on the regional structure of the thermohaline stratification within the...on a regional pattern. Within the limited region covered by the ASIRI 2013 cruises, the full range of thermohaline stratification across the Bay of...range of the regional thermohaline stratification and mesoscale features. 7 HONORS/AWARDS/PRIZES Houghton Lecturer, Massachusetts Institute of Technology. Spring semester 2015

  8. Pockmarks in Passamaquoddy Bay, New Brunswick, Canada

    Science.gov (United States)

    Brothers, Laura; Legere, Christine; Hughes Clark, J.E.; Kelley, J.T.; Barnhardt, Walter; Andrews, Brian; Belknap, D.F.

    2016-01-01

    Pockmarks are seafloor depressions associated with fluid escape (Judd & Hovland 2007). They proliferate in the muddy seafloors of coastal Gulf of Maine and Bay of Fundy, where they are associated with shallow natural gas likely of biogenic origin (Ussler et al. 2003; Rogers et al. 2006; Wildish et al. 2008). In North America, shallow-water pockmark fields are not reported south of Long Island Sound, despite the abundance of gassy, muddy estuaries. The absence of pockmarks south of the limit of North American glaciation suggests that local and regional heterogeneities, possibly related to glacial or sea-level history or bedrock geology, influence pockmark field distribution. In shallow-water embayments, such as Passamaquoddy Bay, New Brunswick, pockmarks can be large (>200 m diameter) and number in the thousands.

  9. The Bay of Pigs: Revisiting Two Museums

    Directory of Open Access Journals (Sweden)

    Peter Read

    2007-08-01

    Full Text Available The Museum of Playa Giron (the Bay of Pigs in the region of Cienega De Zapata, Cuba, celebrates the repulse of Brigade 2506 as the first reverse of US imperialism on the American continents. The equivalent Brigade 2506 Museum in Miami, dedicated to and maintained by the members of Brigade 2506, celebrates defeat at the Bay of Pigs as moral victory for the Cuban exiles. The forces were indeed implacable foes. Yet between the museums can be detected some curious similarities. Both present the common theme of the confrontation between forces of good and evil. Both celebrate the philosophy that dying for one’s country is the greatest good a citizen may achieve. Both museums fly the common Cuban flag. Both museums identify a common enemy: the United States of America. This article, by comparing the displays in the two museums, analyses some cultural elements of what, despite decades of separation, in some ways remains a common Cuban culture.

  10. Specific authorial features and history of art: The frescoes of the upper bays of the narthex and porch of St. Sophia in Ohrid and the wall paintings of Ohrid and the neighbouring regions

    Directory of Open Access Journals (Sweden)

    Radujko Milan

    2011-01-01

    Full Text Available The paper deals with the members of the groups of painters engaged in painting the upper bays of the narthex (second half of the fourth decade of the fourteenth century and the porch (before 1346 of St. Sophia in Ohrid, as well as the work of the members of those groups of painters in later monuments in Ohrid, in Ljuboten and the Monastery of King Marko.

  11. Thatcher Bay, Washington, Nearshore Restoration Assessment

    Science.gov (United States)

    Breems, Joel; Wyllie-Echeverria, Sandy; Grossman, Eric E.; Elliott, Joel

    2009-01-01

    The San Juan Archipelago, located at the confluence of the Puget Sound, the Straits of Juan de Fuca in Washington State, and the Straits of Georgia, British Columbia, Canada, provides essential nearshore habitat for diverse salmonid, forage fish, and bird populations. With 408 miles of coastline, the San Juan Islands provide a significant portion of the available nearshore habitat for the greater Puget Sound and are an essential part of the regional efforts to restore Puget Sound (Puget Sound Shared Strategy 2005). The nearshore areas of the San Juan Islands provide a critical link between the terrestrial and marine environments. For this reason the focus on restoration and conservation of nearshore habitat in the San Juan Islands is of paramount importance. Wood-waste was a common by-product of historical lumber-milling operations. To date, relatively little attention has been given to the impact of historical lumber-milling operations in the San Juan Archipelago. Thatcher Bay, on Blakely Island, located near the east edge of the archipelago, is presented here as a case study on the restoration potential for a wood-waste contaminated nearshore area. Case study components include (1) a brief discussion of the history of milling operations. (2) an estimate of the location and amount of the current distribution of wood-waste at the site, (3) a preliminary examination of the impacts of wood-waste on benthic flora and fauna at the site, and (4) the presentation of several restoration alternatives for the site. The history of milling activity in Thatcher Bay began in 1879 with the construction of a mill in the southeastern part of the bay. Milling activity continued for more than 60 years, until the mill closed in 1942. Currently, the primary evidence of the historical milling operations is the presence of approximately 5,000 yd3 of wood-waste contaminated sediments. The distribution and thickness of residual wood-waste at the site was determined by using sediment

  12. Wind stress, curl and vertical velocity in the Bay of Bengal during southwest monsoon, 1984

    Digital Repository Service at National Institute of Oceanography (India)

    Babu, M.T.; Heblekar, A.K.; Murty, C.S.

    Wind distribution observed during southwest monsoon of 1984 has used to derive the mean wind stress for the season at every 1 degree square grid and curl over the Bay of Bengal. Two regions of maximum wind stress are present over the Bay of Bengal...

  13. 75 FR 32209 - North San Pablo Bay Restoration and Reuse Project

    Science.gov (United States)

    2010-06-07

    ... Recycling Program. The purpose of the Project is to create a regional wastewater reuse project to provide... Bureau of Reclamation North San Pablo Bay Restoration and Reuse Project AGENCY: Bureau of Reclamation..., and Sonoma County Water Agency (SCWA), acting as project administrator of the North Bay Water Reuse...

  14. Numerical Simulation of Regional Circulation in the Monterey Bay Region

    Science.gov (United States)

    2003-12-01

    Air-Sea Technology ( DieCAST ) ocean model, which provides high com- putational accuracy and low numerical dissipation and dispersion. The numerical...system DieCAST model and uses the immersed boundary method to represent the coastal geometry and bathymetry (Tseng & Ferziger 2003) in the local model. The...we explore the impact of the hydrostatic approximation by comparing results from hydrostatic and non-hydrostatic versions of the DieCAST model applied

  15. FY 1999 cooperation program - Comprehensive research cooperation in environmental technology. Research cooperation in toxic/hazardous waste management in the Laguna de Bay region; 1999 nendo kenkyu kyoryoku jigyo. Kankyo gijutsu sogo kenkyu kyoryoku - Raguna ko chiiki ni okeru yudoku yugai haikibutsu ni kansuru kenkyu kyoryoku

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    For the purpose of establishing preventive measures for water contamination in the Laguna de Bay region, the Philippines, where the water contamination is in progress and the eutrophication is feared, a research cooperation project was carried out on the water quality contamination monitoring technology (measuring method/analysis method/prediction method). In the survey of the state of generation of toxic/hazardous waste, the following were grasped based on the existing data: amount of use of toxic/hazardous substances in factories, state of generation of waste, situation of the processing/disposal, etc. In the detailed survey of the situation of pollution in the Laguna de Bay region, specimens of water quality and bottom material were collected from the lake and rivers thereinto, and qualitative/quantitative analysis of contaminants was made using atomic absorption spectrophotometer and gaschromatograph mass spectrometer. As to the evaluation of pollutant sources and control method, the paper conducted the introduction of measures generally taken against pollutant sources, study of a method to grasp the behavior of contaminants by the environmental assessment method for the closed water area, etc. The training was also conducted for researchers/engineers widely in charge of management of toxic/hazardous waste in the Philippines. (NEDO)

  16. Kepentingan India Dalam Kerjasama Bimstec (Bay of Bengal Initiative for Multi Sectoral Technical and Economic Cooperation)

    OpenAIRE

    Pahlawan, Indra; Rahmadhani, Nathacia

    2016-01-01

    This research tried to examine India€™s interest in a regional cooperation combined the two different regional namely Asia and Southeast Asia known as BIMSTEC or Bay of Bengal Initiative for Multi- sectoral Technical and Economic Cooperation, consist of seven countries at the rim bay of Bengal, Bangladesh India, Myanmar, Sri Lanka, Thailand Nepal and Bhutan. Initiated in 1997 BIMSTEC is the only sub-regional grouping to promoting harmonious economic development and can serve as an effective b...

  17. Environmental and sanitary conditions of Guanabara Bay, Rio de Janeiro

    Directory of Open Access Journals (Sweden)

    Giovana De Oliveira Fistarol

    2015-11-01

    Full Text Available Guanabara Bay is the second largest bay in the coast of Brazil, with an area of 384 km2. In its surroundings live circa 16 million inhabitants, out of which 6 million live in Rio de Janeiro city, one of the largest cities of the country, and the host of the 2016 Olympic Games. Anthropogenic interference in Guanabara Bay area started early in the XVI century, but environmental impacts escalated from 1930, when this region underwent an industrialization process. Herein we present an overview of the current environmental and sanitary conditions of Guanabara Bay, a consequence of all these decades of impacts. We will focus on microbial communities, how they may affect higher trophic levels of the aquatic community and also human health. The anthropogenic impacts in the bay are flagged by heavy eutrophication and by the emergence of pathogenic microorganisms that are either carried by domestic and/or hospital waste (e.g. virus, KPC-producing bacteria, and fecal coliforms, or that proliferate in such conditions (e.g. vibrios. Antibiotic resistance genes are commonly found in metagenomes of Guanabara Bay planktonic microorganisms. Furthermore, eutrophication results in recurrent algal blooms, with signs of a shift towards flagellated, mixotrophic groups, including several potentially harmful species. A recent large-scale fish kill episode, and a long trend decrease in fish stocks also reflects the bay’s degraded water quality. Although pollution of Guanabara Bay is not a recent problem, the hosting of the 2016 Olympic Games propelled the government to launch a series plans to restore the bay’s water quality. If all plans are fully implemented, the restoration of Guanabara Bay and its shores may be one of the best legacies of the Olympic Games in Rio de Janeiro.

  18. Potential climate-change impacts on the Chesapeake Bay

    Science.gov (United States)

    Najjar, R.; Pyke, C.; Adams, M.; Breitburg, D.; Hershner, C.; Kemp, M.; Howarth, R.; Mulholland, M.; Paolisso, M.; Secor, D.; Sellner, K.; Wardrop, D.; Wood, R.

    2008-12-01

    We review current understanding of the potential impact of climate change on the Chesapeake Bay. Scenarios for carbon dioxide emissions indicate that by the end of the 21st century the Bay region will experience significant changes in climate forcings with respect to historic conditions, including increases in carbon dioxide concentrations, sea level, and water temperature of 50-160 percent, 0.7-1.6 m, and 2-6 K, respectively. Also likely are increases in precipitation amount (particularly in the winter and spring), precipitation intensity, intensity of tropical and extratropical cyclones (though their frequency may decrease), and sea-level variability. The greatest uncertainty is associated with changes in annual streamflow, though it is likely that winter and spring flows will increase. Climate change alone will cause the Bay to function very differently in the future. Likely changes include: (1) an increase in coastal flooding and submergence of estuarine wetlands; (2) an increase in salinity variability on many time scales; (3) an increase in harmful algae; (4) an increase in hypoxia; (5) a reduction of eelgrass, the dominant submerged aquatic vegetation in the Bay; and (6) altered interactions among trophic levels, with warm-water fish and shellfish species ultimately being favored in the Bay. The magnitude of these changes is sensitive to the carbon dioxide emission trajectory, so that actions taken now to reduce carbon dioxide emissions will reduce climate impacts on the Bay. Research needs include improved precipitation and streamflow projections for the Bay watershed and whole-system monitoring and modeling (supplemented by process studies) that can capture the likely non-linear responses of the Chesapeake Bay system to climate variability and change.

  19. Long-term morphologic evolution of the Hangzhou Bay, China

    Science.gov (United States)

    Wen, W.; Zhijun, D.; Hualiang, X.

    2013-12-01

    Estuaries are the most productive ecosystems of coastal zones in the world, which are significant to mankind as places of navigation, recreation and commerce as well as extensive and diverse habitats for wildlife. However, most estuary environments in the world had occurred greatly changes in recent decades. These estuaries have suffered from impacts of forcing factors including wave climate, mean sea level change and storm surge, especial to the intensive human activities such as training wall construction, channel dredging, sand mining and dam constructions. Thus, there have been increasing concerns about estuary environment changes under effects of different factors. Riverine loads into the Changjiang Estuary have declined dramatically with the construction of Three Gorges Dam (TGD) in 2003. The morphological evolution of the Hangzhou bay that located the southern proximity of the Yangtze estuary starts to attract increasing attentions due to most material of the Hangzhou bay received from Yangtze estuary. In this paper, historical bathymetric charts were digitized and analyzed within a GIS to provide quantitative estimate of changes in volumes in different regions below 0 m elevation. The results show that Hangzhou bay has experienced a major loss in estuarine volume of about 15% with annual mean sediment deposition rate of 80 million m3/a during the last 75 years. However, there is a large-scale spatial adjustment in Hangzhou bay: Bathymetric changes of the Hangzhou bay can be rapidly shifted within the range of 8-10 classes. Volume of the Jinshanzui upstream of the Hangzhou bay has obviously decreased in the last 75 years, especially during 2003-2008. However, Volume of the southern Hangzhou bay has experienced slowly decrease with minor deposition. The northern Hangzhou bay had largely volume changes with rapidly decrease during 1931-1981, and drastically increase since 2003. Further analysis of the bathymetric data relating to possible factors indicates

  20. Bayes multiple decision functions.

    Science.gov (United States)

    Wu, Wensong; Peña, Edsel A

    2013-01-01

    This paper deals with the problem of simultaneously making many (M) binary decisions based on one realization of a random data matrix X. M is typically large and X will usually have M rows associated with each of the M decisions to make, but for each row the data may be low dimensional. Such problems arise in many practical areas such as the biological and medical sciences, where the available dataset is from microarrays or other high-throughput technology and with the goal being to decide which among of many genes are relevant with respect to some phenotype of interest; in the engineering and reliability sciences; in astronomy; in education; and in business. A Bayesian decision-theoretic approach to this problem is implemented with the overall loss function being a cost-weighted linear combination of Type I and Type II loss functions. The class of loss functions considered allows for use of the false discovery rate (FDR), false nondiscovery rate (FNR), and missed discovery rate (MDR) in assessing the quality of decision. Through this Bayesian paradigm, the Bayes multiple decision function (BMDF) is derived and an efficient algorithm to obtain the optimal Bayes action is described. In contrast to many works in the literature where the rows of the matrix X are assumed to be stochastically independent, we allow a dependent data structure with the associations obtained through a class of frailty-induced Archimedean copulas. In particular, non-Gaussian dependent data structure, which is typical with failure-time data, can be entertained. The numerical implementation of the determination of the Bayes optimal action is facilitated through sequential Monte Carlo techniques. The theory developed could also be extended to the problem of multiple hypotheses testing, multiple classification and prediction, and high-dimensional variable selection. The proposed procedure is illustrated for the simple versus simple hypotheses setting and for the composite hypotheses setting

  1. Bayes Syndrome and Imaging Techniques.

    Science.gov (United States)

    Betancor, Ivan Hernandez; Izquierdo-Gomez, Maria Manuela; Niebla, Javier Garcia; Laynez-Cerdeña, Ignacio; Garcia-Gonzalez, Martin Jesus; Barragan-Acea, Antonio; Iribarren-Sarriá, Jose Luis; Jimenez-Rivera, Juan Jose; Lacalzada-Almeida, Juan

    2017-07-13

    Interatrial block (IAB) is due to disruption in the Bachmann region (BR). According to whether interatrial electrical conduction is delayed or completely blocked through the BR, it can be classified as IAB of first, second or third degree. On the surface electrocardiogram, a P wave ≥ 120 ms (partial IAB) is observed or associated to the prolongation of the P wave with a biphasic (positive / negative) morphology in the inferior leads (advanced IAB). Bayes syndrome is defined as an advanced IAB associated with atrial arrhythmia, more specifically atrial fibrillation. The purpose of this review is to describe the latest evidence about an entity considered an anatomical and electrical substrate with its own name, which may be a predictor of supraventricular arrhythmia and cardioembolic cerebrovascular accidents, as well as the role of new imaging techniques, such as echocardiographic strain and cardiac magnetic resonance imaging, in characterizing atrial alterations associated with this syndrome and generally in the study of anatomy and atrial function. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  2. Sub-littoral meiobenthos of the northeastern Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Rodrigues, C.L.; Harkantra, S.N.; Parulekar, A.H.

    super(3)m/2 (median = 31.45 x 10 super(3)) Distribution was contagious with varied fauna in the nearshore region On the basis of metabolic index, the food requirement of the benthic community (macro+meio) in the Bay of Bengal was found to be lower than...

  3. The biology of the Arabian Sea and Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Gauns, M.

    This article focusses on the variability in physics and chemistry of the region and investigate its influence on the biology. This article is largely based on the recent observations made during the India JGOFS and BOBPS (Bay of Bengal Process Study...

  4. Economics of wild salmon ecosystems: Bristol Bay, Alaska

    Science.gov (United States)

    John W. Duffield; Christopher J. Neher; David A. Patterson; Oliver S. Goldsmith

    2007-01-01

    This paper provides an estimate of the economic value of wild salmon ecosystems in the major watershed of Bristol Bay, Alaska. The analysis utilizes both regional economic and social benefit-cost accounting frameworks. Key sectors analyzed include subsistence, commercial fishing, sport fishing, hunting, and nonconsumptive wildlife viewing and tourism. The mixed cash-...

  5. 33 CFR 165.1195 - Regulated Navigation Area; Humboldt Bay Bar Channel and Humboldt Bay Entrance Channel, Humboldt...

    Science.gov (United States)

    2010-07-01

    ...; Humboldt Bay Bar Channel and Humboldt Bay Entrance Channel, Humboldt Bay, California. 165.1195 Section 165... Channel and Humboldt Bay Entrance Channel, Humboldt Bay, California. (a) Location. The Regulated Navigation Area (RNA) includes all navigable waters of the Humboldt Bay Bar Channel and the Humboldt Bay...

  6. Multichannel Seismic Reflection - SCAR- Prydz Bay 1980 SDLS CD-ROM vol 8

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are stacked multichannel marine seismic reflection data recorded during 1980 in the Prydz Bay region, by Australian Geological Survey Organization. The...

  7. Multichannel Seismic Reflection Data - SCAR - Prydz Bay - 1984-1985, SDLS CD-ROM vol 21

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are stacked multichannel marine seismic reflection data recorded during 1984-85 in the Prydz Bay region, Antarctica, by the Japan National Oil...

  8. Zooplankton biomass and composition in the western Bay of Bengal during late sw monsoon

    Digital Repository Service at National Institute of Oceanography (India)

    Achuthankutty, C.T.; Madhupratap, M.; Nair, V.R.; Nair, S.R.S.; Rao, T.S.S.

    and neritic regions of the southwestern Bay of Bengal. Other groups like chaetognaths, ostracods, amphipods, euphausiids, fish eggs, fish larvae, polychaetes, cladocerans, planktonic molluscs, etc. contributed to a lesser percentage of the general composition...

  9. Final Environmental Statement : Acquisition of lands for the San Francisco Bay National Wildlife Refuge California

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Federal Government proposes to acquire approximately 23,000 acres of land in the South San Francisco Bay region, Alameda, San Mateo and Santa Clara Counties, to...

  10. Eutrophication in the Chesapeake Bay

    Science.gov (United States)

    Ulanowicz, R. E.

    1978-01-01

    The advantages and limitations of using remote sensing to acquire fast reliable data on the nutrient problem in the Chesapeake Bay ecosystem are discussed. Pollution effects to phytoplankton blooms during late summer and early fall months are also considered.

  11. FL BAY SPECTROUT-DIET

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Juvenile spotted seatrout and other sportfish are being monitored annually over a 6-mo period in Florida Bay to assess their abundance over time relative to...

  12. Missisquoi Bay Phosphorus Model Addendum

    Science.gov (United States)

    This technical memorandum provides results of an extended load reduction simulation. The memorandum serves as an addendum to the main Missisquoi Bay Phosphorus Mass Balance Model report prepared for the Lake Champlain Basin Program by LimnoTech in 2012

  13. Lavaca Bay 1985-1987

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Samples were collected from October 15, 1985 through June 12, 1987 in emergent marsh and non-vegetated habitats throughout the Lavaca Bay system to characterize...

  14. Constructing Puale Bay field camp

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Puale bay is located on the Pacific side of the Alaskan Peninsula across Shelikof Strait from the southern end of Kodiak Island. The weather, although often mild, is...

  15. Spatiotemporal appraisal of TBT contamination and imposex along a tropical bay (Todos os Santos Bay, Brazil).

    Science.gov (United States)

    Artifon, Vanda; Castro, Ítalo Braga; Fillmann, Gilberto

    2016-08-01

    A spatiotemporal evaluation of butyltin contamination was performed between 2010 and 2012 along Todos os Santos Bay (Northeast Brazil) using surface sediments, bivalve tissues (Anomalocardia brasiliana and Mytella guyanensis), and imposex occurrence (Stramonita rustica). The spatial study detected high tributyltin (TBT) levels (maximum values of 262 ng Sn g (-1) - 21,833 ng Sn g(-1) of total organic carbon - for surface sediments and 421 ng Sn g(-1) for bivalve tissues) in the innermost part of the bay. The TBT levels detected in M. guyanensis tissues might cause human health risk since local population consumes these organisms. These high concentrations observed in the bivalves might result in ingestions higher than the safe limits established by European Food Safety Authority (250 ng TBT kg(-1) day(-1)). Considering the temporal evaluation, no difference (p > 0.05) was observed between TBT concentrations in sediments obtained during the two sampling campaigns (2010/2011 and 2012). However, the increasing predominance of TBT metabolites (butyltin degradation index (BDI) >1) in more recent sediments indicates further degradation of old TBT inputs. In spite of that, recent inputs are still evident at this region. Nevertheless, a reduction of imposex parameters in S. rustica over the last decade suggests an overall decline in the TBT contamination, at least in the outermost and possible less impacted region of the bay. The TBT contamination is probably reducing due to the national and international legislative restrictions on the use of TBT as antifouling biocide. The contamination levels, however, are still relevant especially in the inner part of Todos os Santos Bay since they are above those that are likely to cause toxicity to the biota.

  16. A model for the geomorphology of the Carolina Bays

    Science.gov (United States)

    Zamora, Antonio

    2017-04-01

    Geometrical analysis of the Carolina Bays using Google Earth in combination with LiDAR data makes it possible to postulate that the bays formed as the result of impacts, rather than from eolian and lacustrine processes. The Carolina Bays are elliptical conic sections with width-to-length ratios averaging 0.58 that are radially oriented toward the Great Lakes region. The radial distribution of ejecta is one characteristic of impacts, and the width-to-length ratios of the ellipses correspond to cones inclined at approximately 35°, which is consistent with ballistic trajectories from the point of convergence. These observations, and the fact that these geomorphological features occur only on unconsolidated soil close to the water table, make it plausible to propose that the Carolina Bays are the remodeled remains of oblique conical craters formed on ground liquefied by the seismic shock waves of secondary impacts of glacier ice boulders ejected by an extraterrestrial impact on the Laurentide Ice Sheet. Mathematical analysis using ballistic equations and scaling laws relating yield energy to crater size provide clues about the magnitude of the extraterrestrial event. An experimental model elucidates the remodeling mechanisms and provides an explanation for the morphology and the diverse dates of the bays.

  17. Submersed aquatic vegetation in Chesapeake Bay: Sentinel species in a changing world

    Science.gov (United States)

    Orth, Robert J.; Dennison, William C.; Lefcheck, Jonathon S.; Gurbisz, Cassie; Hannam, Michael; Keisman, Jennifer; Landry, J. Brooke; Moore, Kenneth A.; Murphy, Rebecca R.; Patrick, Christopher J.; Testa, Jeremy; Weller, Donald E.; Wilcox, David J.

    2017-01-01

    Chesapeake Bay has undergone profound changes since European settlement. Increases in human and livestock populations, associated changes in land use, increases in nutrient loadings, shoreline armoring, and depletion of fish stocks have altered the important habitats within the Bay. Submersed aquatic vegetation (SAV) is a critical foundational habitat and provides numerous benefits and services to society. In Chesapeake Bay, SAV species are also indicators of environmental change because of their sensitivity to water quality and shoreline development. As such, SAV has been deeply integrated into regional regulations and annual assessments of management outcomes, restoration efforts, the scientific literature, and popular media coverage. Even so, SAV in Chesapeake Bay faces many historical and emerging challenges. The future of Chesapeake Bay is indicated by and contingent on the success of SAV. Its persistence will require continued action, coupled with new practices, to promote a healthy and sustainable ecosystem.

  18. Bayes and empirical Bayes estimators of abundance and density from spatial capture-recapture data.

    Directory of Open Access Journals (Sweden)

    Robert M Dorazio

    Full Text Available In capture-recapture and mark-resight surveys, movements of individuals both within and between sampling periods can alter the susceptibility of individuals to detection over the region of sampling. In these circumstances spatially explicit capture-recapture (SECR models, which incorporate the observed locations of individuals, allow population density and abundance to be estimated while accounting for differences in detectability of individuals. In this paper I propose two Bayesian SECR models, one for the analysis of recaptures observed in trapping arrays and another for the analysis of recaptures observed in area searches. In formulating these models I used distinct submodels to specify the distribution of individual home-range centers and the observable recaptures associated with these individuals. This separation of ecological and observational processes allowed me to derive a formal connection between Bayes and empirical Bayes estimators of population abundance that has not been established previously. I showed that this connection applies to every Poisson point-process model of SECR data and provides theoretical support for a previously proposed estimator of abundance based on recaptures in trapping arrays. To illustrate results of both classical and Bayesian methods of analysis, I compared Bayes and empirical Bayes esimates of abundance and density using recaptures from simulated and real populations of animals. Real populations included two iconic datasets: recaptures of tigers detected in camera-trap surveys and recaptures of lizards detected in area-search surveys. In the datasets I analyzed, classical and Bayesian methods provided similar - and often identical - inferences, which is not surprising given the sample sizes and the noninformative priors used in the analyses.

  19. BOBMEX: The Bay of Bengal Monsoon Experiment

    Digital Repository Service at National Institute of Oceanography (India)

    Bhat, G.S.; Gadgil, S.; Kumar, P.V.H.; Kalsi, S.R.; Madhusoodanan, P.; Murty, V.S.N.; Rao, C.V.K.P.; RameshBabu, V.; Rao, L.V.G.; Rao, R.R.; Ravichandran, M.; Reddy, K.G.; Rao, P.Sanjeeva; Sengupta, D.; Sikka, D.R.; Swain, J.; Vinayachandran, P.N.

    , ocean, and their interface to gain deeper insight into some of the processes that govern the variability of organized convection over the bay. Simultaneous time series observations were carried out in the northern and southern Bay of Bengal from ships...

  20. 77 FR 57107 - Bandon Marsh, Nestucca Bay, and Siletz Bay National Wildlife Refuges, Coos, Tillamook, and...

    Science.gov (United States)

    2012-09-17

    ... Fish and Wildlife Service Bandon Marsh, Nestucca Bay, and Siletz Bay National Wildlife Refuges, Coos... conservation plans and environmental assessments (Draft CCP/EAs) for three Oregon refuges-- Bandon Marsh... . Include ``Bandon Marsh, Nestucca Bay, and Siletz Bay draft CCP and EA'' in the subject line of the message...

  1. 33 CFR 100.112 - Swim the Bay, Narragansett Bay, Narragansett, RI.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Swim the Bay, Narragansett Bay, Narragansett, RI. 100.112 Section 100.112 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND..., Narragansett Bay, Narragansett, RI. (a) Regulated area. All waters of the East Passage of Narragansett Bay...

  2. 77 FR 70891 - Safety Zone; Bay Bridge Construction, San Francisco Bay, San Francisco, CA

    Science.gov (United States)

    2012-11-28

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Bay Bridge Construction, San Francisco Bay..., CA in support of the Bay Bridge Construction Safety Zone from November 1, 2012 through July 31, 2013.... 1221 et seq.). CALTRANS will sponsor the Bay Bridge Construction Safety Zone on November 1, 2012...

  3. Bayes linear statistics, theory & methods

    CERN Document Server

    Goldstein, Michael

    2007-01-01

    Bayesian methods combine information available from data with any prior information available from expert knowledge. The Bayes linear approach follows this path, offering a quantitative structure for expressing beliefs, and systematic methods for adjusting these beliefs, given observational data. The methodology differs from the full Bayesian methodology in that it establishes simpler approaches to belief specification and analysis based around expectation judgements. Bayes Linear Statistics presents an authoritative account of this approach, explaining the foundations, theory, methodology, and practicalities of this important field. The text provides a thorough coverage of Bayes linear analysis, from the development of the basic language to the collection of algebraic results needed for efficient implementation, with detailed practical examples. The book covers:The importance of partial prior specifications for complex problems where it is difficult to supply a meaningful full prior probability specification...

  4. Contaminant transport in Massachusetts Bay

    Science.gov (United States)

    Butman, Bradford

    Construction of a new treatment plant and outfall to clean up Boston Harbor is currently one of the world's largest public works projects, costing about $4 billion. There is concern about the long-term impact of contaminants on Massachusetts Bay and adjacent Gulf of Maine because these areas are used extensively for transportation, recreation, fishing, and tourism, as well as waste disposal. Public concern also focuses on Stellwagen Bank, located on the eastern side of Massachusetts Bay, which is an important habitat for endangered whales. Contaminants reach Massachusetts Bay not only from Boston Harbor, but from other coastal communities on the Gulf of Maine, as well as from the atmosphere. Knowledge of the pathways, mechanisms, and rates at which pollutants are transported throughout these coastal environments is needed to address a wide range of management questions.

  5. Hierarchical mixtures of naive Bayes classifiers

    OpenAIRE

    Wiering, M.A.

    2002-01-01

    Naive Bayes classifiers tend to perform very well on a large number of problem domains, although their representation power is quite limited compared to more sophisticated machine learning algorithms. In this pa- per we study combining multiple naive Bayes classifiers by using the hierar- chical mixtures of experts system. This system, which we call hierarchical mixtures of naive Bayes classifiers, is compared to a simple naive Bayes classifier and to using bagging and boosting for combining ...

  6. ASTER Images San Francisco Bay Area

    Science.gov (United States)

    2000-01-01

    These images of the San Francisco Bay region were acquired on March 3, 2000 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. Each covers an area 60 kilometers (37 miles) wide and 75 kilometers (47 miles) long. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER will image the Earth for the next 6 years to map and monitor the changing surface of our planet.Upper Left: The color infrared composite uses bands in the visible and reflected infrared. Vegetation is red, urban areas are gray; sediment in the bays shows up as lighter shades of blue. Thanks to the 15 meter (50-foot) spatial resolution, shadows of the towers along the Bay Bridge can be seen.Upper right: A composite of bands in the short wave infrared displays differences in soils and rocks in the mountainous areas. Even though these regions appear entirely vegetated in the visible, enough surface shows through openings in the vegetation to allow the ground to be imaged.Lower left: This composite of multispectral thermal bands shows differences in urban materials in varying colors. Separation of materials is due to differences in thermal emission properties, analogous to colors in the visible.Lower right: This is a color coded temperature image of water temperature, derived from the thermal bands. Warm waters are in white and yellow, colder waters are blue. Suisun Bay in the upper right is fed directly from the cold Sacramento River. As the water flows through San Pablo and San Francisco Bays on the way to the Pacific, the waters warm up.Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for

  7. Backscatter imagery in Jobos Bay

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 1x1 meter resolution backscatter mosaic of Jobos Bay, Puerto Rico (in NAD83 UTM 19 North). The backscatter values are in relative 8-bit (0 –...

  8. Classification using Hierarchical Naive Bayes models

    DEFF Research Database (Denmark)

    Langseth, Helge; Dyhre Nielsen, Thomas

    2006-01-01

    Classification problems have a long history in the machine learning literature. One of the simplest, and yet most consistently well-performing set of classifiers is the Naïve Bayes models. However, an inherent problem with these classifiers is the assumption that all attributes used to describe......, termed Hierarchical Naïve Bayes models. Hierarchical Naïve Bayes models extend the modeling flexibility of Naïve Bayes models by introducing latent variables to relax some of the independence statements in these models. We propose a simple algorithm for learning Hierarchical Naïve Bayes models...

  9. bayesPop: Probabilistic Population Projections

    Directory of Open Access Journals (Sweden)

    Hana Ševčíková

    2016-12-01

    Full Text Available We describe bayesPop, an R package for producing probabilistic population projections for all countries. This uses probabilistic projections of total fertility and life expectancy generated by Bayesian hierarchical models. It produces a sample from the joint posterior predictive distribution of future age- and sex-specific population counts, fertility rates and mortality rates, as well as future numbers of births and deaths. It provides graphical ways of summarizing this information, including trajectory plots and various kinds of probabilistic population pyramids. An expression language is introduced which allows the user to produce the predictive distribution of a wide variety of derived population quantities, such as the median age or the old age dependency ratio. The package produces aggregated projections for sets of countries, such as UN regions or trading blocs. The methodology has been used by the United Nations to produce their most recent official population projections for all countries, published in the World Population Prospects.

  10. Empirical bayes model comparisons for differential methylation analysis.

    Science.gov (United States)

    Teng, Mingxiang; Wang, Yadong; Kim, Seongho; Li, Lang; Shen, Changyu; Wang, Guohua; Liu, Yunlong; Huang, Tim H M; Nephew, Kenneth P; Balch, Curt

    2012-01-01

    A number of empirical Bayes models (each with different statistical distribution assumptions) have now been developed to analyze differential DNA methylation using high-density oligonucleotide tiling arrays. However, it remains unclear which model performs best. For example, for analysis of differentially methylated regions for conservative and functional sequence characteristics (e.g., enrichment of transcription factor-binding sites (TFBSs)), the sensitivity of such analyses, using various empirical Bayes models, remains unclear. In this paper, five empirical Bayes models were constructed, based on either a gamma distribution or a log-normal distribution, for the identification of differential methylated loci and their cell division-(1, 3, and 5) and drug-treatment-(cisplatin) dependent methylation patterns. While differential methylation patterns generated by log-normal models were enriched with numerous TFBSs, we observed almost no TFBS-enriched sequences using gamma assumption models. Statistical and biological results suggest log-normal, rather than gamma, empirical Bayes model distribution to be a highly accurate and precise method for differential methylation microarray analysis. In addition, we presented one of the log-normal models for differential methylation analysis and tested its reproducibility by simulation study. We believe this research to be the first extensive comparison of statistical modeling for the analysis of differential DNA methylation, an important biological phenomenon that precisely regulates gene transcription.

  11. Empirical Bayes Model Comparisons for Differential Methylation Analysis

    Directory of Open Access Journals (Sweden)

    Mingxiang Teng

    2012-01-01

    Full Text Available A number of empirical Bayes models (each with different statistical distribution assumptions have now been developed to analyze differential DNA methylation using high-density oligonucleotide tiling arrays. However, it remains unclear which model performs best. For example, for analysis of differentially methylated regions for conservative and functional sequence characteristics (e.g., enrichment of transcription factor-binding sites (TFBSs, the sensitivity of such analyses, using various empirical Bayes models, remains unclear. In this paper, five empirical Bayes models were constructed, based on either a gamma distribution or a log-normal distribution, for the identification of differential methylated loci and their cell division—(1, 3, and 5 and drug-treatment-(cisplatin dependent methylation patterns. While differential methylation patterns generated by log-normal models were enriched with numerous TFBSs, we observed almost no TFBS-enriched sequences using gamma assumption models. Statistical and biological results suggest log-normal, rather than gamma, empirical Bayes model distribution to be a highly accurate and precise method for differential methylation microarray analysis. In addition, we presented one of the log-normal models for differential methylation analysis and tested its reproducibility by simulation study. We believe this research to be the first extensive comparison of statistical modeling for the analysis of differential DNA methylation, an important biological phenomenon that precisely regulates gene transcription.

  12. Impact of Bay-Breeze Circulations on Surface Air Quality and Boundary Layer Export

    Science.gov (United States)

    Loughner, Christopher P.; Tzortziou, Maria; Follette-Cook, Melanie; Pickering, Kenneth E.; Goldberg, Daniel; Satam, Chinmay; Weinheimer, Andrew; Crawford, James H.; Knapp, David J.; Montzka, Denise D.; hide

    2014-01-01

    Meteorological and air-quality model simulations are analyzed alongside observations to investigate the role of the Chesapeake Bay breeze on surface air quality, pollutant transport, and boundary layer venting. A case study was conducted to understand why a particular day was the only one during an 11-day ship-based field campaign on which surface ozone was not elevated in concentration over the Chesapeake Bay relative to the closest upwind site and why high ozone concentrations were observed aloft by in situ aircraft observations. Results show that southerly winds during the overnight and early-morning hours prevented the advection of air pollutants from the Washington, D.C., and Baltimore, Maryland, metropolitan areas over the surface waters of the bay. A strong and prolonged bay breeze developed during the late morning and early afternoon along the western coastline of the bay. The strength and duration of the bay breeze allowed pollutants to converge, resulting in high concentrations locally near the bay-breeze front within the Baltimore metropolitan area, where they were then lofted to the top of the planetary boundary layer (PBL). Near the top of the PBL, these pollutants were horizontally advected to a region with lower PBL heights, resulting in pollution transport out of the boundary layer and into the free troposphere. This elevated layer of air pollution aloft was transported downwind into New England by early the following morning where it likely mixed down to the surface, affecting air quality as the boundary layer grew.

  13. Microbial diversity in restored wetlands of San Francisco Bay

    Energy Technology Data Exchange (ETDEWEB)

    Theroux, Susanna [Lawrence Berkeley National Lab. (LBNL), Walnut Creek, CA (United States). Dept. of Energy Joint Genome Inst.; Hartman, Wyatt [Lawrence Berkeley National Lab. (LBNL), Walnut Creek, CA (United States). Dept. of Energy Joint Genome Inst.; He, Shaomei [Lawrence Berkeley National Lab. (LBNL), Walnut Creek, CA (United States). Dept. of Energy Joint Genome Inst.; Univ. of Wisconsin, Madison, WI (United States); Tringe, Susannah [Lawrence Berkeley National Lab. (LBNL), Walnut Creek, CA (United States). Dept. of Energy Joint Genome Inst.

    2013-12-09

    Wetland ecosystems may serve as either a source or a sink for atmospheric carbon and greenhouse gases. This delicate carbon balance is influenced by the activity of belowground microbial communities that return carbon dioxide and methane to the atmosphere. Wetland restoration efforts in the San Francisco Bay-Delta region may help to reverse land subsidence and possibly increase carbon storage in soils. However, the effects of wetland restoration on microbial communities, which mediate soil metabolic activity and carbon cycling, are poorly studied. In an effort to better understand the underlying factors which shape the balance of carbon flux in wetland soils, we targeted the microbial communities in a suite of restored and historic wetlands in the San Francisco Bay-Delta region. Using DNA and RNA sequencing, coupled with greenhouse gas monitoring, we profiled the diversity and metabolic potential of the wetland soil microbial communities along biogeochemical and wetland age gradients. Our results show relationships among geochemical gradients, availability of electron acceptors, and microbial community composition. Our study provides the first genomic glimpse into microbial populations in natural and restored wetlands of the San Francisco Bay-Delta region and provides a valuable benchmark for future studies.

  14. Formation of summer phytoplankton bloom in the northwestern Bay of Bengal in a coupled physical‐ecosystem model

    National Research Council Canada - National Science Library

    Thushara, V; Vinayachandran, P. N

    2016-01-01

    The Bay of Bengal (BoB) is considered to be a region of low biological productivity, owing to nutrient limitation, caused by strong salinity stratification induced by the freshwater influx from rivers and precipitation...

  15. Evaluating Bay Area Methane Emission Inventory

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Marc [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Jeong, Seongeun [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2016-03-01

    As a regulatory agency, evaluating and improving estimates of methane (CH4) emissions from the San Francisco Bay Area is an area of interest to the Bay Area Air Quality Management District (BAAQMD). Currently, regional, state, and federal agencies generally estimate methane emissions using bottom-up inventory methods that rely on a combination of activity data, emission factors, biogeochemical models and other information. Recent atmospheric top-down measurement estimates of methane emissions for the US as a whole (e.g., Miller et al., 2013) and in California (e.g., Jeong et al., 2013; Peischl et al., 2013) have shown inventories underestimate total methane emissions by ~ 50% in many areas of California, including the SF Bay Area (Fairley and Fischer, 2015). The goal of this research is to provide information to help improve methane emission estimates for the San Francisco Bay Area. The research effort builds upon our previous work that produced methane emission maps for each of the major source sectors as part of the California Greenhouse Gas Emissions Measurement (CALGEM) project (http://calgem.lbl.gov/prior_emission.html; Jeong et al., 2012; Jeong et al., 2013; Jeong et al., 2014). Working with BAAQMD, we evaluate the existing inventory in light of recently published literature and revise the CALGEM CH4 emission maps to provide better specificity for BAAQMD. We also suggest further research that will improve emission estimates. To accomplish the goals, we reviewed the current BAAQMD inventory, and compared its method with those from the state inventory from the California Air Resources Board (CARB), the CALGEM inventory, and recent published literature. We also updated activity data (e.g., livestock statistics) to reflect recent changes and to better represent spatial information. Then, we produced spatially explicit CH4 emission estimates on the 1-km modeling grid used by BAAQMD. We present the detailed activity data, methods and derived emission maps by sector

  16. Tropical cyclones in the Bay of Bengal and extreme sea-level projections along the east coast of India in a future climate scenario

    Digital Repository Service at National Institute of Oceanography (India)

    Unnikrishnan, A.S.; RameshKumar, M.R.; Sindhu, B.

    , Dubai, UAE The simulations from the regional climate model, PRECIS (Providing REgional Climates for Impacts Studies), were analysed for the occurrence of tropical cyclones in the Bay of Bengal in a baseline scenario (1961–1990) and a future...

  17. Distribution of biochemical constituents in the surface sediments of western coastal Bay of Bengal: Influence of river discharge and water column properties

    Digital Repository Service at National Institute of Oceanography (India)

    Kumar, B.S.K.; Sarma, V.V.S.S.; Krishna, M.S.

    of discharged water and associated biogeochemical processes in the water column. The northwest (NW) region of coastal Bay of Bengal was influenced by discharges from Ganges river while peninsular (monsoonal) rivers influenced the southwest (SW) region. The NW...

  18. Sources, fate, and transport of nitrogen and phosphorus in the Chesapeake Bay watershed-An empirical model

    Science.gov (United States)

    Ator, Scott W.; Brakebill, John W.; Blomquist, Joel D.

    2011-01-01

    Spatially Referenced Regression on Watershed Attributes (SPARROW) was used to provide empirical estimates of the sources, fate, and transport of total nitrogen (TN) and total phosphorus (TP) in the Chesapeake Bay watershed, and the mean annual TN and TP flux to the bay and in each of 80,579 nontidal tributary stream reaches. Restoration efforts in recent decades have been insufficient to meet established standards for water quality and ecological conditions in Chesapeake Bay. The bay watershed includes 166,000 square kilometers of mixed land uses, multiple nutrient sources, and variable hydrogeologic, soil, and weather conditions, and bay restoration is complicated by the multitude of nutrient sources and complex interacting factors affecting the occurrence, fate, and transport of nitrogen and phosphorus from source areas to streams and the estuary. Effective and efficient nutrient management at the regional scale in support of Chesapeake Bay restoration requires a comprehensive understanding of the sources, fate, and transport of nitrogen and phosphorus in the watershed, which is only available through regional models. The current models, Chesapeake Bay nutrient SPARROW models, version 4 (CBTN_v4 and CBTP_v4), were constructed at a finer spatial resolution than previous SPARROW models for the Chesapeake Bay watershed (versions 1, 2, and 3), and include an updated timeframe and modified sources and other explantory terms.

  19. The Chesapeake Bay impact structure

    Science.gov (United States)

    Powars, David S.; Edwards, Lucy E.; Gohn, Gregory S.; Horton, J. Wright

    2015-10-28

    About 35 million years ago, during late Eocene time, a 2-mile-wide asteroid or comet smashed into Earth in what is now the lower Chesapeake Bay in Virginia. The oceanic impact vaporized, melted, fractured, and (or) displaced the target rocks and sediments and sent billions of tons of water, sediments, and rocks into the air. Glassy particles of solidified melt rock rained down as far away as Texas and the Caribbean. Models suggest that even up to 50 miles away the velocity of the intensely hot air blast was greater than 1,500 miles per hour, and ground shaking was equivalent to an earthquake greater than magnitude 8.0 on the Richter scale. Large tsunamis affected most of the North Atlantic basin. The Chesapeake Bay impact structure is among the 20 largest known impact structures on Earth.

  20. Bayes reconstruction of missing teeth

    DEFF Research Database (Denmark)

    Sporring, Jon; Jensen, Katrine Hommelhoff

    2008-01-01

     We propose a method for restoring the surface of tooth crowns in a 3D model of a human denture, so that the pose and anatomical features of the tooth will work well for chewing. This is achieved by including information about the position and anatomy of the other teeth in the mouth. Our system...... contains two major parts: A statistical model of a selection of tooth shapes and a reconstruction of missing data. We use a training set consisting of 3D scans of dental cast models obtained with a laser scanner, and we have build a model of the shape variability of the teeth, their neighbors...... regularization of the log-likelihood estimate based on differential geometrical properties of teeth surfaces, and we show general conditions under which this may be considered a Bayes prior.Finally we use Bayes method to propose the reconstruction of missing data, for e.g. finding the most probable shape...

  1. Influenza in Bristol Bay, 1919

    OpenAIRE

    Maria Gilson deValpine

    2015-01-01

    The 1918 influenza pandemic has been blamed for as many as 50 million deaths worldwide. Like all major disasters, the full story of the pandemic includes smaller, less noted episodes that have not attracted historical attention. The story of the 1919 wave of the influenza pandemic in Bristol Bay Alaska is one such lost episode. It is an important story because the most accessible accounts—the Congressional Record and t...

  2. Remotely Sensing Pollution: Detection and Monitoring of PCBs in the San Francisco Bay

    Science.gov (United States)

    Hilton, A.; Kudela, R. M.; Bausell, J.

    2016-12-01

    While the EPA banned polychlorinated biphenyls (PCBs) in 1977, they continue to persist in San Francisco Bay (SF Bay), often at dangerously high concentrations due to their long half-life. However, in spite of their associated health and environmental risks, PCB monitoring within SF Bay is extremely limited, due in large part to the high costs, both in terms of labor and capital that are associated with it. In this study, a cost effective alternative to in-situ PCB sampling is presented by demonstrating the feasibility of PCB detection via remote sensing. This was done by first establishing relationships between in-situ measurements of sum of 40 PCB concentrations and total suspended sediment concentration (SSC) collected from 1998-2006 at 37 stations distributed throughout SF Bay. A correlation was discovered for all stations at (R2 =0.32), which improved markedly upon partitioning stations into north bay, (R2 =0.64), central bay (R2 =0.80) and south bay (R2 =0.52) regions. SSC was then compared from three USGS monitoring stations with temporally consistent Landsat 8 imagery. The resulting correlation between Landsat 8 (Rrs 654) and SSC measured at USGS stations (R2 =0.50) was validated using an Airborne Visible/ Infrared Imaging Spectrometer (AVIRIS) image. The end product is a two-step empirical algorithm that can derive PCB from Landsat 8 imagery within SF Bay. This algorithm can generate spatial PCB concentration maps for SF Bay, which can in turn be utilized to increase ability to forecast PCB concentration. The observation that correlation between AVIRIS (Rrs 657) and SSC was stronger than that of Landsat 8 suggests that the accuracy of this algorithm could be enhanced with improved atmospheric correction.

  3. Potential climate change impacts on a tropical estuary: Hilo Bay, Hawaii

    Science.gov (United States)

    Adolf, J.; LaPinta, J.; Marusek, J.; Pascoe, K.; Pugh, A.

    2016-02-01

    Hilo Bay is a tropical estuarine ecosystem on the northeast (windward) coast of Hawai`i Island that is potentially vulnerable to climate change effects mediated through elevated water temperatures and/or changing rainfall patterns that impact river and groundwater fluxes. Here, we document trends in water temperature, river flow and phytoplankton dynamics in Hilo Bay. Hilo Bay is fed by two major rivers, Wailuku and Honoli`i, both of which have shown long term declines in output over their 85 and 38 year monitoring periods (USGS), respectively. Time series of groundwater inputs to Hilo Bay do not exist, but the average estimated rate rivals that of average river inputs. Daily average Hilo Bay water temperatures have increased at a rate of 0.35 degrees C per year (p < 0.001) since measurement by the Hilo Bay water quality buoy began in 2010, with the warmest temperatures on record recorded Sept 2015. Salinity did not show a trend over this same time period. Phytoplankton showed a pronounced seasonal cycle in Hilo Bay with a long term average of 3.7 mg m-3 and dominance by diatoms that exploit the co-availability of silica and nitrate in this environment. On shorter time scales of days to < 1 week, flood events dramatically reduce Hilo Bay salinity, temperature and phytoplankton biomass. Coincidental atmospheric warming, SST warming in the adjacent North Pacific ocean, and declining river flows will likely work together to result in elevated SST in Hilo Bay if observed trends continue. The El Nino event that started this year is expected to exacerbate this warming through reduce river flow and warmer regional SST.

  4. Community-based observations on sustainable development in southern Hudson Bay

    Energy Technology Data Exchange (ETDEWEB)

    Arragutainaq, L.; Fleming, B

    Inuit residents of the Belcher Islands in Hudson Bay practice sustainable development over a wide region, and are heavily dependent on fish and wildlife for food. Large-scale hydroelectric developments on rivers emptying into Hudson Bay and James Bay threaten both the environment and the traditional economy and culture of those residents. The main focus of concern is the James Bay hydroelectric project, part 1 of which (La Grande) is now operational. In addition, hydroelectric projects in Manitoba and Ontario may also affect the region. The residents feel that the subdivision of each project into components, each subject to a separate environmental review and assessment, works in favor of the project proponents and does not address the issues of interest to those affected by the project. Neither does such a review process address questions related to the cumulative development of many projects over a long term. The Belcher Islands are remote from the territorial and national governments, neither of which seem to be giving the James Bay developments as much attention as seems necessary. The island community has identified its primary ecological concerns on part 2 of the James Bay project and presented them at a public hearing. These concerns include the long-term impacts of the project on the marine environment and the kinds of compensation, if any, for such impacts. 7 refs., 2 figs.

  5. Biodiversity inventories and conservation of the marine fishes of Bootless Bay, Papua New Guinea.

    Science.gov (United States)

    Drew, Joshua A; Buxman, Charlene L; Holmes, Darcae D; Mandecki, Joanna L; Mungkaje, Augustine J; Richardson, Amber C; Westneat, Mark W

    2012-08-01

    The effective management and conservation of biodiversity is predicated on clearly defined conservation targets. Species number is frequently used as a metric for conservation prioritization and monitoring changes in ecosystem health. We conducted a series of synoptic surveys focusing on the fishes of the Bootless Bay region of Papua New Guinea to generate a checklist of fishes of the region. Bootless Bay lies directly south of Port Moresby, the capital of Papua New Guinea, and experiences the highest human population density of any marine area in the country. Our checklist will set a baseline against which future environmental changes can be tracked. We generated a checklist of 488 fish species in 72 families found in Bootless Bay during a two-week sampling effort. Using incident-based methods of species estimation, we extrapolate there to be approximately 940 fish species in Bootless Bay, one of the lowest reported numbers in Papua New Guinea. Our data suggest that the Bootless Bay ecosystem of Papua New Guinea, while diverse in absolute terms, has lower fish biodiversity compared to other shallow marine areas within the country. These differences in faunal diversity are most likely a combination of unequal sampling effort as well as biophysical factors within Bootless Bay compounded by historical and/or contemporary anthropogenic disturbances.

  6. Biodiversity inventories and conservation of the marine fishes of Bootless Bay, Papua New Guinea

    Directory of Open Access Journals (Sweden)

    Drew Joshua A

    2012-08-01

    Full Text Available Abstract Background The effective management and conservation of biodiversity is predicated on clearly defined conservation targets. Species number is frequently used as a metric for conservation prioritization and monitoring changes in ecosystem health. We conducted a series of synoptic surveys focusing on the fishes of the Bootless Bay region of Papua New Guinea to generate a checklist of fishes of the region. Bootless Bay lies directly south of Port Moresby, the capital of Papua New Guinea, and experiences the highest human population density of any marine area in the country. Our checklist will set a baseline against which future environmental changes can be tracked. Results We generated a checklist of 488 fish species in 72 families found in Bootless Bay during a two-week sampling effort. Using incident-based methods of species estimation, we extrapolate there to be approximately 940 fish species in Bootless Bay, one of the lowest reported numbers in Papua New Guinea. Conclusions Our data suggest that the Bootless Bay ecosystem of Papua New Guinea, while diverse in absolute terms, has lower fish biodiversity compared to other shallow marine areas within the country. These differences in faunal diversity are most likely a combination of unequal sampling effort as well as biophysical factors within Bootless Bay compounded by historical and/or contemporary anthropogenic disturbances.

  7. Review of suspended sediment in lower South Bay relevant to light attenuation and phytoplankton blooms

    Science.gov (United States)

    Schoellhamer, David H.; Shellenbarger, Gregory; Downing-Kunz, Maureen; Manning, Andrew J.

    2016-01-01

    Lower South Bay (LSB), a shallow subembayment of San Francisco Bay (SFB), is situated south of the Dumbarton Bridge, and is surrounded by, and interconnected with, a network of sloughs, marshes, and former salt ponds undergoing restoration (Figure ES.1). LSB receives 120 million gallons per day of treated wastewater effluent from three publicly owned treatment works (POTWs) that service San Jose and the densely populated surrounding region. During the dry season, when flows from creeks and streams are at their minimum, POTW effluent comprises the majority of freshwater flow to Lower South Bay. Although LSB has a large tidal prism, it experiences limited net exchange with the surrounding Bay, because much of the water that leaves on ebb tides returns during the subsequent flood tides. The limited exchange leads to distinctly different biogeochemical conditions in LSB compared to other SFB subembayments, including LSB having the highest nutrient concentrations and highest phytoplankton biomass.

  8. Implementing FORMS for the Monterey Bay Forecasting System Using HOPS and ROMS

    National Research Council Canada - National Science Library

    Gangopadhyay, Avijit

    2004-01-01

    ...) to implement the feature-oriented regional modeling system (FORMS) capabilities in the West Coast ROMS and HOPS modeling efforts for synoptic nowcast, forecast and 3D-VARS and ESSE-based assimilation in the Monterey Bay region, and (iii...

  9. Zooplankton Biomass Data from Prince William Sound, Icy Bay and Yakutat Bay, Alaska 2010-2011

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset includes zooplankton biomass from Prince William Sound, Icy Bay and Yakutat Bay, Alaska. Zooplankton were sampled with a ring net (0.6 m diameter with...

  10. [Characteristics of Pahs pollution in sediments from Leizhou coastal marine area, Liusha Bay and Shenzhen Bay].

    Science.gov (United States)

    Zhao, Li-Rong; Sun, Sheng-Li; Ke, Sheng

    2012-04-01

    Leizhou coastal marine area, Liusha Bay and Shenzhen Bay represented open coastal area and half-closed bay, respectively. This study discussed the differences of PAHs concentration levels, spatial distribution and sources in sediments from these three marine areas. The results showed that detected ratios of 15 PAHs were 100%, and major compounds were 3-ring and 4-ring PAHs, especialy Phe, Fla, Pry and Bbf; Sigma PAHs concentration was Leizhou the outside, and the aquaculture > the non-aquaculture in Liusha Bay and Shenzhen Bay. It suggested that large-scale mariculture inside bay played an important role in PAHs pollution and might make it serious. Oil, fossil fuels and biomass burning were the dominant sources of PAHs in sediments from Leizhou coastal area, Liusha Bay and Shenzhen Bay.

  11. Linear dimension reduction and Bayes classification

    Science.gov (United States)

    Decell, H. P., Jr.; Odell, P. L.; Coberly, W. A.

    1978-01-01

    An explicit expression for a compression matrix T of smallest possible left dimension K consistent with preserving the n variate normal Bayes assignment of X to a given one of a finite number of populations and the K variate Bayes assignment of TX to that population was developed. The Bayes population assignment of X and TX were shown to be equivalent for a compression matrix T explicitly calculated as a function of the means and covariances of the given populations.

  12. BayesMT: Bayesian inference for the seismic moment tensor using regional and teleseismic-P waveforms with first-motion data and a calibrated prior distribution of velocity models

    Science.gov (United States)

    Ford, S. R.; Chiang, A.; Kim, S.; Letort, J.; Tkalcic, H.; Walter, W. R.

    2016-12-01

    The largest source of uncertainty in any source inversion is the velocity model used to construct the transfer function employed in the forward model that relates observed ground motion to the seismic moment tensor. We attempt to incorporate this uncertainty into an estimation of the seismic moment tensor using a posterior distribution of velocity models based on different and complementary data sets, including thickness constraints, velocity profiles, gravity data, surface wave group velocities, and regional body wave traveltimes. The posterior distribution of velocity models is then used to construct a prior distribution of Green's functions for use in Bayesian inference of an unknown seismic moment tensor using regional and teleseismic-P waveforms with first-motion data. The use of multiple data sets is important for gaining resolution to different components of the moment tensor. The combined likelihood is estimated using data-specific error models and the posterior of the seismic moment tensor is estimated and interpreted in terms of most-probable source-type. Prepared by LLNL under Contract DE-AC52-07NA27344. LLNL-ABS-676976.

  13. 78 FR 45061 - Safety Zone; Sister Bay Marina Fest Fireworks and Ski Show, Sister Bay, WI

    Science.gov (United States)

    2013-07-26

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Sister Bay Marina Fest Fireworks and Ski... intended to restrict vessels from a portion of Sister Bay due to a fireworks display and ski show. This... with the fireworks display and ski show in Sister Bay on August 31, 2013. DATES: This rule is effective...

  14. 78 FR 46813 - Safety Zone; Evening on the Bay Fireworks; Sturgeon Bay, WI

    Science.gov (United States)

    2013-08-02

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Evening on the Bay Fireworks; Sturgeon Bay... of Sturgeon Bay due to a fireworks display. This temporary safety zone is necessary to protect the surrounding public and vessels from the hazards associated with the fireworks display. DATES: This rule is...

  15. Evaluation of the activity concentration of {sup 226}Ra, {sup 228}Ra and {sup 210}Pb in sediments from Antarctica in the Admiralty bay region; Avaliacao da concentracao de atividade de Ra-226, Ra-228 e Pb-210 em sedimentos provenientes da Antartica na regiao da baia do Almirantado

    Energy Technology Data Exchange (ETDEWEB)

    Mora, Tamires de Araujo

    2015-07-01

    The natural radionuclides from radioactive series of {sup 238}U, {sup 235}U and {sup 232}Th have been applied as tracers in environmental studies for understanding the dynamics that occur in both marine and terrestrial environment, as for example, in research of oceanic processes and management of the coastal region. In the marine environment, these radionuclides can be used to estimate biogeochemical fluxes of marine particles and nutrients that occur in the water column as well as in the sediment. Several research works applied the distribution and the respective disequilibrium degree of natural radionuclides in the environment, including geochronological models for obtaining historical information on samples of certain sediment profile. In this study we performed a radiochemical characterization of the distribution of {sup 226}Ra, {sup 228}Ra and {sup 210}Pb from a sedimentary column called 1B (248 cm long) collected in the Admiralty Bay, Antarctic Peninsula region. The methodology used included the acid leaching of sediment samples followed by the radiochemical sequential separation of {sup 226}Ra and {sup 228}Ra by co-precipitation with Ba(Ra)SO{sub 4} and {sup 210}Pb by co-precipitation with PbCrO{sub 4}. All measurements were carried out by counting of gross alpha and gross beta measures in a low background gas flow proportional detector. The activity concentrations of {sup 226}Ra and {sup 210}Pb were used to estimate the unsupported {sup 210}Pb activities present in sediment profile 1 B. Based on unsupported {sup 210}Pb data and the application of the CIC model (Constant Initial Concentration), it was possible to determine the sedimentation rate of 0.59 ± 0.05 cm /year. (author)

  16. Investigation of Tidal Power, Cobscook Bay, Maine. Environmental Appendix.

    Science.gov (United States)

    1980-08-01

    Nevertheless, some worms are harvested in Cobscook Bay . Lobsters are also found in Cobscook Bay , although not in sufficient numbers to support a...ring-billed gull, sanderling, black-bellied plover, semipalmated plover, least sandpiper and dowitcher. Cobscook Bay (and Bay of Fundy in general...tidal power development in the upper Bay of Fundy . Circulation between Cobscook Bay and the Gulf of Maine will be reduced resulting in decreased

  17. The Bay of Bengal : an ideal laboratory for studying salinity

    Science.gov (United States)

    Vialard, jerome; Lengaigne, Matthieu; Akhil, Valiya; Chaitanya, Akurathi; Krishna-Mohan, Krishna; D'Ovidio, Francesco; Keerthi, Madhavan; Benshila, Rachid; Durand, Fabien; Papa, Fabrice; Suresh, Iyappan; Neetu, Singh

    2017-04-01

    The Bay of Bengal combines several unique features that make it an excellent laboratory to study the variability of salinity and its potential effects on the oceanic circulation and climate. This basin receives very large quantities of freshwater in association to the southwest monsoon, either directly from rain or indirectly through the runoffs of the Ganges-Brahmaputra and Irrawaddy. This large quantity of freshwater in a small, semi enclosed basin results in some of the lowest sea surface salinities (SSS) and strongest near-surface haline stratification in the tropical band. The strong monsoon winds also drive an energetic circulation, which exports the excess water received during the monsoon and results in strong horizontal salinity gradients. In this talk, I will summarize several studies of the Bay of Bengal salinity variability and its impacts undertaken in the context of an Indo-French collaboration. In situ data collected along the coast by fishermen and model results show that the intense, coastally-trapped East India Coastal Current (EICC) transports the very fresh water near the Ganges-Brahmaputra river mouth along the eastern Bay of Bengal rim to create a narrow, very fresh "river in the sea" after the southwest monsoon. The salinity-induced pressure gradient contributes to almost 50% of the EICC intensity and sustains mesoscale eddy generation through its effect on horizontal current shears and baroclinic gradients. Oceanic eddies play a strong role in exporting this fresh water from the coast to the basin interior. This "river in the sea" has a strong interannual variability related to the EICC remote modulation by the Indian Ocean Dipole (a regional climate mode). I will also discuss the potential effect of haline stratification on the regional climate through its influence on the upper ocean budget. Finally, I will briefly discuss the performance of remote-sensing for observing SSS in the Bay of Bengal.

  18. Can we predict the frequency of cyclones over Bay of Bengal during October-December?

    Digital Repository Service at National Institute of Oceanography (India)

    Sadhuram, Y.

    and the SST in the northern Australia-Indonesia region (5° S - 15° S : 120° E - 160° E : (Box A) and Bay of Bengal (5° N - 15° N : 85° E - 100° E; (Box B) ( Fig. 1), has been examined using the long term data of 123 years (1891- 2013). The SST... (daily). Fig. 1. Study area (Box A : 5° S - 15° S; 120° E - 160° E) (north Australia Indonesia region) and Box B (5° N - 15° N; 85° E - 100 °E) (Bay of Bengal...

  19. Shifting shoals and shattered rocks : How man has transformed the floor of west-central San Francisco Bay

    Science.gov (United States)

    Chin, John L.; Wong, Florence L.; Carlson, Paul R.

    2004-01-01

    San Francisco Bay, one of the world's finest natural harbors and a major center for maritime trade, is referred to as the 'Gateway to the Pacific Rim.' The bay is an urbanized estuary that is considered by many to be the major estuary in the United States most modified by man's activities. The population around the estuary has grown rapidly since the 1850's and now exceeds 7 million people. The San Francisco Bay area's economy ranks as one of the largest in the world, larger even than that of many countries. More than 10 million tourists are estimated to visit the bay region each year. The bay area's population and associated development have increasingly changed the estuary and its environment. San Francisco Bay and the contiguous Sacramento-San Joaquin Delta encompass roughly 1,600 square miles (4,100 km2) and are the outlet of a major watershed that drains more than 40 percent of the land area of the State of California. This watershed provides drinking water for 20 million people (two thirds of the State's population) and irrigates 4.5 million acres of farmland and ranchland. During the past several decades, much has been done to clean up the environment and waters of San Francisco Bay. Conservationist groups have even bought many areas on the margins of the bay with the intention of restoring them to a condition more like the natural marshes they once were. However, many of the major manmade changes to the bay's environment occurred so long ago that the nature of them has been forgotten. In addition, many changes continue to occur today, such as the introduction of exotic species and the loss of commercial and sport fisheries because of declining fish populations. The economy and population of the nine counties that surround the bay continue to grow and put increasing pressure on the bay, both direct and indirect. Therefore, there are mixed signals for the future health and welfare of San Francisco Bay. The San Francisco Bay estuary consists of three

  20. PENGEMBANGAN USAHA TERNAK AYAM BURAS OLEH PETANI MISKIN DI TELUK KULISUSU KABUPATEN BUTON UTARA PROVINSI SULAWESI TENGGARA (Development Of Farming Livestock Domestic Poultry By Poor Farmers In Kulisusu Bay, North Buton Regions

    Directory of Open Access Journals (Sweden)

    Mukhtar Mukhtar

    2013-07-01

    memadai di tingkat lokal.   ABSTRACT The precentage of people who are poor of the high for each country in the Kulisusu gulf region (about 75% is the principal socio-economic problems of agriculture that were examined in this study. Meanwhile, the source of needs of people in villages that are not directly adjacent to the sea, comes from the domestic poultry breeding. The aims of the study are (1 assessing the extent of the production, reception and free-range poultry farm income at the farmers’ level, and (2 assessing the efficacy and usefulness of native chicken breeding at the farmers’ level. The study was concentrated on three areas namely village administration of Koepisino village (district Bonegunu, Dampalajaya village (West Kulisusudistrict and Lakonea village (district Kulisusu. This study is a survey research using qualitative descriptive analysis. The results showed that the domestic poultry livestock farming in the gulf region is still considered as sideline job with still very low productivity per year. Despite the success and benefits of livestock farming on the coast of the Kulisusu  gulf of domestic poultry is considered very successful and economically beneficial, the farm (since 2004 till 2008 cannot be relied upon to overcome poverty due to the relatively small contribution to the total household income of farmers. Free-range chicken farm in the Gulf coastal villages Kulisusu capacity also needs to be developed, so that in the future it can be a solution to overcome the problem of poverty. Accordingly, it is necessary to hold outreach activities and technical training on procurement and feeding of local raw materials and improvement of livestock farming systems semi-intensive native chicken. Also it is really necessary empowerment efforts through mentoring local chicken farmers to obtain cash capital and adequate capital goods at the local level.

  1. Development of a Hydrodynamic and Transport model of Bellingham Bay in Support of Nearshore Habitat Restoration

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Taiping; Yang, Zhaoqing; Khangaonkar, Tarang

    2010-04-22

    In this study, a hydrodynamic model based on the unstructured-grid finite volume coastal ocean model (FVCOM) was developed for Bellingham Bay, Washington. The model simulates water surface elevation, velocity, temperature, and salinity in a three-dimensional domain that covers the entire Bellingham Bay and adjacent water bodies, including Lummi Bay, Samish Bay, Padilla Bay, and Rosario Strait. The model was developed using Pacific Northwest National Laboratory’s high-resolution Puget Sound and Northwest Straits circulation and transport model. A sub-model grid for Bellingham Bay and adjacent coastal waters was extracted from the Puget Sound model and refined in Bellingham Bay using bathymetric light detection and ranging (LIDAR) and river channel cross-section data. The model uses tides, river inflows, and meteorological inputs to predict water surface elevations, currents, salinity, and temperature. A tidal open boundary condition was specified using standard National Oceanic and Atmospheric Administration (NOAA) predictions. Temperature and salinity open boundary conditions were specified based on observed data. Meteorological forcing (wind, solar radiation, and net surface heat flux) was obtained from NOAA real observations and National Center for Environmental Prediction North American Regional Analysis outputs. The model was run in parallel with 48 cores using a time step of 2.5 seconds. It took 18 hours of cpu time to complete 26 days of simulation. The model was calibrated with oceanographic field data for the period of 6/1/2009 to 6/26/2009. These data were collected specifically for the purpose of model development and calibration. They include time series of water-surface elevation, currents, temperature, and salinity as well as temperature and salinity profiles during instrument deployment and retrieval. Comparisons between model predictions and field observations show an overall reasonable agreement in both temporal and spatial scales. Comparisons of

  2. Search for Bioindicators of Pollution in the Guanabara Bay: Integrations of Ecologic Patterns

    Directory of Open Access Journals (Sweden)

    Claudia G. Vilela

    2003-01-01

    Full Text Available Guanabara Bay, since its discovery, has largely changed with the human occupation causing large amounts of deposited sediment and waste, as well as domestic and industry sewage. Surface sediment was analysed for foraminifera and ostracoda distribution, diversity and dominance studies. These results were compared with TOC analyses aiming the determination of pollution bioindicators. In general, foraminifera dominant species were Ammonia tepida, Buliminella elegantissima and Quinqueloculina seminulum. The foraminifera assemblages presented distinct abundance and diversity values in different regions of the bay. The diversity was higher in the entrance (south and in the central region than in the north region of the bay. The dominant species, that are characteristic of stressed environments, presented higher values of abundance in the north region. The TOC values increased from south to north regions, and were inversely proportional to foraminifera diversity. The very high TOC values in very polluted areas suggest sediment deposition in anoxic-dysoxic environment. The ostracoda Gen. Cyprideis was dominant and its occurrence increased from south to north region. Occurrence of Callistocythere sigmocostata, Xestoleberis sp., Aurila sp., and Paracypris sp. were restricted to the entrance and central area, indicating a preference for less restricted conditions, like marine conditions. Foraminifera and ostracoda characteristic responses to the environment conditions related high TOC values showed their importance as bioindicators of stressed environments caused by anthropogenic pollution, in the Guanabara Bay.

  3. Galveston Bay Area : Land Barrier preliminary design

    NARCIS (Netherlands)

    van Berchum, E.C.; de Vries, P.A.L.; de Kort, R.P.J.

    2016-01-01

    The Galveston Bay Area is under significant risk from hurricane induced flooding. Ever since Hurricane Ike caused billions of damage back in 2008, the option of closing off the Galveston Bay from the Gulf of Mexico was investigated. This report, commissioned by Texas A&M University in Galveston,

  4. Unique thermal record in False Bay

    CSIR Research Space (South Africa)

    Grundlingh, ML

    1993-10-01

    Full Text Available Over the past decade False Bay has assumed a prime position in terms of research in to large South African bays. This is manifested by investigations that cover flow conditions modelling, thermal structure, management, biology and nutrients, geology...

  5. Hierarchical mixtures of naive Bayes classifiers

    NARCIS (Netherlands)

    Wiering, M.A.

    2002-01-01

    Naive Bayes classifiers tend to perform very well on a large number of problem domains, although their representation power is quite limited compared to more sophisticated machine learning algorithms. In this pa- per we study combining multiple naive Bayes classifiers by using the hierar- chical

  6. Traditional Fisheries of Antongil Bay, Madagascar | Doukakis ...

    African Journals Online (AJOL)

    Madagascar's marine fisheries provide revenue and sustenance for the island nation. Antongil Bay, the largest shallow-water bay along Madagascar's eastern coast, harbors significant marine resources and is heavily utilized by traditional, artisanal (shark-fin) and industrial fisheries. Mean hourly catch rates are just under 1 ...

  7. Hardwood re-sprout control in hydrologically restored Carolina Bay depression wetlands.

    Energy Technology Data Exchange (ETDEWEB)

    Moser, Lee, Justin

    2009-06-01

    Carolina bays are isolated depression wetlands located in the upper coastal plain region of the eastern Unites States. Disturbance of this wetland type has been widespread, and many sites contain one or more drainage ditches as a result of agricultural conversion. Restoration of bays is of interest because they are important habitats for rare flora and fauna species. Previous bay restoration projects have identified woody competitors in the seedbank and re-sprouting as impediments to the establishment of herbaceous wetland vegetation communities. Three bays were hydrologically restored on the Savannah River Site, SC, by plugging drainage ditches. Residual pine/hardwood stands within the bays were harvested and the vegetative response of the seedbank to the hydrologic change was monitored. A foliar herbicide approved for use in wetlands (Habitat® (Isopropylamine salt of Imazapyr)) was applied on one-half of each bay to control red maple (Acer rubrum L.), sweet gum (Liquidambar styraciflua L.), and water oak (Quercus nigra L.) sprouting. The effectiveness of the foliar herbicide was tested across a hydrologic gradient in an effort to better understand the relationship between depth and duration of flooding, the intensity of hardwood re-sprout pressure, and the need for hardwood management practices such as herbicide application.

  8. Admiralty Bay Benthos Diversity—A census of a complex polar ecosystem

    Science.gov (United States)

    Siciński, Jacek; Jażdżewski, Krzysztof; Broyer, Claude De; Presler, Piotr; Ligowski, Ryszard; Nonato, Edmundo F.; Corbisier, Thais N.; Petti, Monica A. V.; Brito, Tania A. S.; Lavrado, Helena P.; BŁażewicz-Paszkowycz, Magdalena; Pabis, Krzysztof; Jażdżewska, Anna; Campos, Lucia S.

    2011-03-01

    A thorough census of Admiralty Bay benthic biodiversity was completed through the synthesis of data, acquired from more than 30 years of observations. Most of the available records arise from successive Polish and Brazilian Antarctic expeditions organized since 1977 and 1982, respectively, but also include new data from joint collecting efforts during the International Polar Year (2007-2009). Geological and hydrological characteristics of Admiralty Bay and a comprehensive species checklist with detailed data on the distribution and nature of the benthic communities are provided. Approximately 1300 species of benthic organisms (excluding bacteria, fungi and parasites) were recorded from the bay's entire depth range (0-500 m). Generalized classifications and the descriptions of soft-bottom and hard-bottom invertebrate communities are presented. A time-series analysis showed seasonal and interannual changes in the shallow benthic communities, likely to be related to ice formation and ice melt within the bay. As one of the best studied regions in the maritime Antarctic Admiralty Bay represents a legacy site, where continued, systematically integrated data sampling can evaluate the effects of climate change on marine life. Both high species richness and high assemblage diversity of the Admiralty Bay shelf benthic community have been documented against the background of habitat heterogeneity.

  9. Evidence for mid-Holocene shift in depositional style in Mobile Bay, Alabama

    Science.gov (United States)

    Twichell, David; Kelso, Kyle; Pendleton, Elizabeth A.

    2012-01-01

    The Holocene stratigraphy of Mobile Bay, Alabama, was mapped using a combination of high-resolution seismic data and sediment cores to refine changes in the bay's evolution during this time. The base of the Holocene-era stratigraphy is an erosional surface formed during the last glacial maximum. Overlying Holocene deposits are primarily estuarine mud that has a finely laminated weak acoustic signature. One exception is a thin unit, R1, with varying reflection amplitude that can be traced throughout the southern part of the bay. The continuity of the unit throughout the southern part of the bay suggests a baywide change in sedimentation that was perhaps driven by rapid retreat of the bay-head delta in response to a sudden rise in sea level or an abrupt change in accommodation space due to basin geometry. Along the southern edge of the bay, the R1 unit increases in thickness and reflector amplitude towards Morgan Peninsula. The peninsula itself underwent a period of erosion and narrowing between 4,300 to 3,000 years before present, and the variation in reflector amplitude and the geometry of this part of the R1 unit appear to reflect a period of increased overwashing of the peninsula during this period. Average estuarine sedimentation rates decreased after the formation of the R1 unit, and the decrease coincides with a decline in the rate of sea-level rise. A similar change in depositional style at approximately the same time in neighboring Apalachicola Bay suggests a change that affected the northeastern Gulf of Mexico region and not just Mobile Bay.

  10. Recent Results from Daya Bay

    CERN Document Server

    Zhan, Liang

    2015-01-01

    The Daya Bay reactor neutrino experiment observed electron antineutrino disappearance associated with $\\theta_{13}$ with a significance better than $5\\sigma$ in 2012. The final two of eight antineutrino detectors were installed in the summer of 2012. Including the 404 days of data collected with the full detector configuration resulted in a 3.6 times increase of statistics over the previous result with the 6-AD configuration. With improvements of the systematic uncertainties and better estimation of backgrounds, Daya Bay has measured $\\sin^22\\theta_{13} = 0.084\\pm0.005$ and $|\\Delta m^2_{ee}|=2.42^{+0.10}_{-0.11}\\times 10^{-3}$~eV$^2$. This is the most precise measurement of $\\sin^22\\theta_{13}$ to date and the most precise measurement of of $|\\Delta m^2_{ee}|$ via electron antineutrino disappearance. Several other analysis results are presented, including an independent measurement of $\\theta_{13}$ using inverse-beta decays associated with neutron capture on hydrogen, a measurement of reactor antineutrino fl...

  11. River flow control on the phytoplankton dynamics of Chesapeake Bay

    Science.gov (United States)

    Yu, Qingyun; Wang, You; Tang, Xuexi; Li, Ming

    2013-03-01

    Recent observations support an emerging paradigm that climate variability dominates nutrient enrichment in costal ecosystems, which can explain seasonal and inter-annual variability of phytoplankton community composition, biomass (Chl -a), and primary production (PP). In this paper, we combined observation and modeling to investigate the regulation of phytoplankton dynamics in Chesapeake Bay. The year we chose is 1996 that has high river runoff and is usually called a `wet year'. A 3-D physical-biogeochemical model based on ROMS was developed to simulate the seasonal cycle and the regional distributions of phytoplankton biomass and primary production in Chesapeake Bay. Based on the model results, NO3 presents a strong contrast to the river nitrate load during spring and the highest concentration in the bay reaches around 80 mmol N m-3. Compared with the normal year, phytoplankton bloom in spring of 1996 appears in lower latitudes with a higher concentration. Quantitative comparison between the modeled and observed seasonal averaged dissolved inorganic nitrogen concentrations shows that the model produces reliable results. The correlation coefficient r 2 for all quantities exceeds 0.95, and the skill parameter for the four seasons is all above 0.95.

  12. Biomass and Carbon Stocks of Sofala Bay Mangrove Forests

    Directory of Open Access Journals (Sweden)

    Almeida A. Sitoe

    2014-08-01

    Full Text Available Mangroves could be key ecosystems in strategies addressing the mitigation of climate changes through carbon storage. However, little is known regarding the carbon stocks of these ecosystems, particularly below-ground. This study was carried out in the mangrove forests of Sofala Bay, Central Mozambique, with the aim of quantifying carbon stocks of live and dead plant and soil components. The methods followed the procedures developed by the Center for International Forestry Research (CIFOR for mangrove forests. In this study, we developed a general allometric equation to estimate individual tree biomass and soil carbon content (up to 100 cm depth. We estimated the carbon in the whole mangrove ecosystem of Sofala Bay, including dead trees, wood debris, herbaceous, pneumatophores, litter and soil. The general allometric equation for live trees derived was [Above-ground tree dry weight (kg = 3.254 × exp(0.065 × DBH], root mean square error (RMSE = 4.244, and coefficient of determination (R2 = 0.89. The average total carbon storage of Sofala Bay mangrove was 218.5 Mg·ha−1, of which around 73% are stored in the soil. Mangrove conservation has the potential for REDD+ programs, especially in regions like Mozambique, which contains extensive mangrove areas with high deforestation and degradation rates.

  13. Assessment of marine pollution in Izmir Bay: nutrient, heavy metal and total hydrocarbon concentrations.

    Science.gov (United States)

    Kucuksezgin, F; Kontas, A; Altay, O; Uluturhan, E; Darilmaz, E

    2006-01-01

    Izmir Bay (western Turkey) is one of the great natural bays of the Mediterranean. Izmir is an important industrial and commercial centre and a cultural focal point. The main industries in the region include food processing, oil, soap and paint production, chemical industries, paper and pulp factories, textile industries and metal processing. The mean concentrations showed ranges of 0.01-0.19 and 0.01-10 microM for phosphate, 0.10-1.8 and 0.12-27 microM for nitrate+nitrite, and 0.30-5.8 and 0.43-39 microM for silicate in the outer and middle-inner bays, respectively. The TNO(x)/PO(4) ratio is significantly lower than the Redfield's ratio and nitrogen is the limiting element in the middle-inner bays. Diatoms and dinoflagellates were observed all year around in the bay and are normally nitrogen limited. Metal concentrations ranged between Hg: 0.05-1.3, Cd: 0.005-0.82, Pb: 14-113 and Cr: 29-316 microg g(-1) in the sediments. The results showed significant enrichments during sampling periods from Inner Bay. Outer and middle bays show low levels of heavy metal enrichments except estuary of Gediz River. The concentrations of Hg, Cd and Pb in the outer bay were generally similar to the background levels from the Mediterranean. The levels gradually decreased over the sampling period. Total hydrocarbons concentrations range from 427 to 7800 ng g(-1) of sediments. The highest total hydrocarbon levels were found in the inner bay due to the anthropogenic activities, mainly combustion processes of traffic and industrial activities. The concentrations of heavy metals found in fish varied for Hg: 4.5-520, Cd: 0.10-10 and Pb: 0.10-491 microg kg(-1) in Izmir Bay. There was no significant seasonal variation in metal concentrations. An increase in Hg concentration with increasing length was noted for Mullus barbatus. A person can consume more than 2, 133 and 20 meals per week of fish in human diet would represent the tolerable weekly intake of mercury, cadmium and lead, respectively

  14. Bay Breeze Influence on Surface Ozone at Edgewood, MD During July 2011

    Science.gov (United States)

    Stauffer, Ryan M.; Thompson, Anne M.; Martins, Douglas K.; Clark, Richard D.; Goldberg, Daniel L.; Loughner, Christopher P.; Delgado, Ruben; Dickerson, Russell R.; Stehr, Jeffrey W.; Tzortziou, Maria A.

    2012-01-01

    Surface ozone (O3) was analyzed to investigate the role of the bay breeze on air quality at two locations in Edgewood, Maryland (lat: 39.4deg, lon: -76.3deg) for the month of July 2011. Measurements were taken as part of the first year of NASA's "Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality" (DISCOVER-AQ) Earth Venture campaign and as part of NASA's Geostationary for Coastal and Air Pollution Events Chesapeake Bay Oceanographic campaign with DISCOVER-AQ (Geo-CAPE CBODAQ). Geo-CAPE CBODAQ complements DISCOVER-AQ by providing ship-based observations over the Chesapeake Bay. A major goal of DISCOVER-AQ is determining the relative roles of sources, photochemistry and local meteorology during air quality events in the Mid-Atlantic region of the U.S. Surface characteristics, transport and vertical structures of O3 during bay breezes were identified using in-situ surface, balloon and aircraft data, along with remote sensing equipment. Localized late day peaks in O3 were observed during bay breeze days, maximizing an average of 3 h later compared to days without bay breezes. Of the 10 days of July 2011 that violated the U.S. Environmental Protection Agency (EPA) 8 h O3 standard of 75 parts per billion by volume (ppbv) at Edgewood, eight exhibited evidence of a bay breeze circulation. The results indicate that while bay breezes and the processes associated with them are not necessary to cause exceedances in this area, bay breezes exacerbate poor air quality that sustains into the late evening hours at Edgewood. The vertical and horizontal distributions of O3 from the coastal Edgewood area to the bay also show large gradients that are often determined by boundary layer stability. Thus, developing air quality models that can sufficiently resolve these dynamics and associated chemistry, along with more consistent monitoring of O3 and meteorology on and along the complex coastline of Chesapeake Bay must be a

  15. Regionally coherent trends in colonies of African penguins ...

    African Journals Online (AJOL)

    From 1987 to 2005, numbers of African penguins Spheniscus demersus breeding in South Africa's Western Cape Province increased by about 50%. Numbers decreased at the four northernmost colonies in the region: Lambert's Bay and the three colonies in Saldanha Bay, although at Jutten Island the decrease is inferred ...

  16. Development, implementation, and validation of a modeling system for the San Francisco Bay and Estuary

    Science.gov (United States)

    Chao, Yi; Farrara, John D.; Zhang, Hongchun; Zhang, Yinglong J.; Ateljevich, Eli; Chai, Fei; Davis, Curtiss O.; Dugdale, Richard; Wilkerson, Frances

    2017-07-01

    A three-dimensional numerical modeling system for the San Francisco Bay is presented. The system is based on an unstructured grid numerical model known as Semi-implicit Cross-scale Hydroscience Integrated System Model (SCHISM). The lateral boundary condition is provided by a regional coastal ocean model. The surface forcing is provided by a regional atmospheric model. The SCHISM results from a decadal hindcast run are compared with available tide gauge data, as well as a collection of temperature and salinity profiles. An examination of the observed climatological annual mean salinities at the United States Geological Survey (USGS) stations shows the highest salinities to be in the open ocean and the lowest well north (upstream) of the Central Bay, a pattern that does not change substantially with season. The corresponding mean SCHISM salinities reproduced the observed variations with location quite well, though with a fresh bias. The lowest values within the Bay occur during spring and the highest values during autumn, mirroring the seasonal variations in river discharge. The corresponding observed mean temperatures within the Bay were 2 to 3° C cooler in the Central Bay than to either the north or south. This observed pattern of a cooler Central Bay was not particularly well reproduced in the SCHISM results, which also showed a cold bias. Examination of the seasonal means revealed that the cool Central Bay pattern is found only during summer in the SCHISM results. The persistent cold and fresh biases in the model control run were nearly eliminated in a sensitivity run with modifications to the surface heat flux and river discharge. The surface atmospheric forcing and the heat flux at the western boundary are found to be the two major terms in a SCHISM-based heat budget analysis of the mean seasonal temperature cycle for the Central Bay. In the Central Bay salt budget, freshwater discharged by rivers into upstream portions of the Bay to the north balanced by the

  17. Bioinvasion in a Brazilian bay: filling gaps in the knowledge of southwestern Atlantic biota.

    Directory of Open Access Journals (Sweden)

    Barbara L Ignacio

    Full Text Available BACKGROUND: Biological invasions are a major cause of global species change. Nevertheless, knowledge about the distribution and ecology of introduced species is regionally biased, and many gaps in knowledge exist for most developing countries. METHODOLOGY/PRINCIPAL FINDINGS: To study the zoobenthos on the hard substratum of the Ilha Grande Bay, a survey was conducted on both natural and artificial substrata at three depths and seven sites. The species recorded were classified as native, cryptogenic or introduced. Multivariate analyses were conducted to assess the prevalence of introduced species in these communities and to compare the distribution of species on natural and artificial substrata of this bay to identify possible discrepancies in habitat use. Of the 61 species, 25 were cryptogenic, 10 were introduced and 26 were native. Similar numbers of introduced species were found on both natural and artificial substrata, though the community composition was significantly different between them. We also compared the species composition of the Ilha Grande Bay survey to other inventories taken around the world. The highest similarities were found between the Ilha Grande Bay inventory and the Atlantic coastal region (Tampa Bay, USA and the Gulf of Mexico, American Samoa and Pearl Harbor (USA inventories. CONCLUSIONS/SIGNIFICANCE: This study presents the first published comprehensive list of hard substratum sessile marine invertebrate species in a Brazilian bay. The high percentage of cryptogenic species reveals gaps in both zoological records and information on introduced species for the Brazilian coast. The introduced species successfully colonized different sites in the Ilha Grande Bay, including both natural and artificial substrata. In addition, we find that artificial structures may not be good surrogates for natural rocky shores and may represent an ecological threat. Comparisons with other inventories suggest a history of broad

  18. MARS: a cabled observatory testbed in Monterey Bay

    Science.gov (United States)

    McNutt, M.; Massion, G.; Raybould, K.; Bellingham, J.; Paull, C.

    2003-04-01

    With funding from the U.S. National Science Foundation and the David and Lucile Packard Foundation, the Monterey Bay Aquarium Research Institute (MBARI) will be installing a deep-sea observatory in Monterey Bay, California, that will serve as a test bed for a future regional-scale cabled observatory. Monterey Bay offers a variety of active processes for scientific inquiry, including a very productive zone of ocean upwelling, a seismically active strand of the San Andreas fault system, cold seeps, and a very dynamic submarine canyon. The MARS (Monterey Accelerated Research System) cable will extend more than 60 km offshore to an instrument node at a depth of approximately 1.2 km. Extension cords can be run by remotely operated vehicles (ROVs) from the cable node up to several kilometers away in order to provide greater flexibility in siting instruments. The observatory will be serviced using ROVs and will serve as a test bed for developing new sensors, instruments systems, experiment protocols, and mobile platforms for which submarine cables will provide power and two-way communications. In addition to serving as a test bed for instrumentation and platforms, the MARS project will demonstrate models for how to operate, service, and manage a community facility of this sort. In cooperation with our outreach partner, the Monterey Bay Aquarium, we will be examining ways to exploit the full potential of deep-sea observatories for student education and public information. We will also be preparing a proposal to the Integrated Ocean Drilling Program (IODP) to provide a nearby drill hole for connecting bore-hole experiments to the MARS cable, thereby accelerating the development of new tools for probing Earth beneath the oceans.

  19. Holocene tephrochronology of the Cold Bay area, southwest Alaska Peninsula

    Science.gov (United States)

    Carson, E.C.; Fournelle, J.H.; Miller, T.P.; Mickelson, D.M.

    2002-01-01

    The major-element glass geochemistry of 92 tephra samples from the southwest Alaska Peninsula provides the basis for establishing a Holocene tephrochronology for the region. Electron microprobe analysis has been combined with field descriptions of samples, stratigraphic relationships between tephra samples and sample localities, and glass shard micro-morphology to correlate these sampled distal tephra units throughout the area of Cold Bay and adjacent Morzhovoi Bay. Radiocarbon dating provides age constraints on correlated horizons. Previous research had clearly delineated only one horizon in the region, the so-called 'Funk/Fisher' ash, dating to between 8425 ± 350 and 9130 ± 140 14C yr BP. In addition to constraining the bimodal andesitic and dacitic glass chemistry of that horizon, this study has recognized six additional tephra layers in the area. Two horizons pre-date the Funk/Fisher ash and four are younger than it. A tephra containing dacitic and andesitic components was identified in the vicinity of Morzhovoi Bay, with a minimum age of 9300 ± 80 14C yr BP and a maximum age of 10,200 ± 75 14C yr BP. A rhyolitic horizon composed of cm-sized, rounded pumice clasts was identified in the vicinity of Cold Bay; it has been correlated to the ca 9500 BP eruption of Roundtop volcano on Unimak Island. The four younger tephra beds date to between 6070 ± 340 and 3600 ± 140 14C yr BP. The oldest of the four is rhyodacitic, followed by a mixed rhyodacitic-andesitic horizon, another rhyodacitic horizon, and finally an andesitic layer. Comparison of all the correlated horizons to proximal samples collected on Unimak Island provides conclusive geochemical evidence that the ca 9100 BP Caldera-forming eruption of Fisher volcano is the source of the Funk/Fisher ash. Correlation between the rhyodacitic tephra horizons and proximal samples from Fisher volcano suggests that Fisher Caldera is the source of one of the rhyodacitic tephra horizons that post-dates the Funk

  20. 19 CFR 7.11 - Guantanamo Bay Naval Station.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Guantanamo Bay Naval Station. 7.11 Section 7.11... TREASURY CUSTOMS RELATIONS WITH INSULAR POSSESSIONS AND GUANTANAMO BAY NAVAL STATION § 7.11 Guantanamo Bay Naval Station. Articles of foreign origin may enter the area (both land and water) of the Guantanamo Bay...

  1. Ecology of selected marine communities in Glacier Bay: Zooplankton, forage fish, seabirds and marine mammals

    Science.gov (United States)

    Robards, Martin D.; Drew, Gary S.; Piatt, John F.; Anson, Jennifer Marie; Abookire, Alisa A.; Bodkin, James L.; Hooge, Philip N.; Speckman, Suzann G.

    2003-01-01

    We studied oceanography (including primary production), secondary production, small schooling fish (SSF), and marine bird and mammal predators in Glacier Bay during 1999 and 2000. Results from these field efforts were combined with a review of current literature relating to the Glacier Bay environment. Since the conceptual model developed by Hale and Wright (1979) ‘changes and cycles’ continue to be the underlying theme of the Glacier Bay ecosystem. We found marked seasonality in many of the parameters that we investigated over the two years of research, and here we provide a comprehensive description of the distribution and relative abundance of a wide array of marine biota. Glacier Bay is a tidally mixed estuary that leads into basins, which stratify in summer, with the upper arms behaving as traditional estuaries. The Bay is characterized by renewal and mixing events throughout the year, and markedly higher primary production than in many neighboring southeast Alaska fjords (Hooge and Hooge, 2002). Zooplankton diversity and abundance within the upper 50 meters of the water column in Glacier Bay is similar to communities seen throughout the Gulf of Alaska. Zooplankton in the lower regions of Glacier Bay peak in abundance in late May or early June, as observed at Auke Bay and in the Gulf of Alaska. The key distinction between the lower Bay and other estuaries in the Gulf of Alaska is that a second smaller peak in densities occurs in August. The upper Bay behaved uniformly in temporal trends, peaking in July. Densities had begun to decline in August, but were still more than twice those observed in that region in May. The highest density of zooplankton observed was 17,870 organisms/m3 in Tarr Inlet during July. Trends in zooplankton community abundance and diversity within the lower Bay were distinct from upper-Glacier Bay trends. Whereas the lower Bay is strongly influenced by Gulf of Alaska processes, local processes are the strongest influence in the upper-Bay

  2. Hampton roads regional Water-Quality Monitoring Program

    Science.gov (United States)

    Porter, Aaron J.; Jastram, John D.

    2016-12-02

    IntroductionHow much nitrogen, phosphorus, and suspended solids are contributed by the highly urbanized areas of the Hampton Roads region in Virginia to Chesapeake Bay? The answer to this complex question has major implications for policy decisions, resource allocations, and efforts aimed at restoring clean waters to Chesapeake Bay and its tributaries. To quantify the amount of nitrogen, phosphorus, and suspended solids delivered to the bay from this region, the U.S. Geological Survey has partnered with the Hampton Roads Sanitation District (HRSD), in cooperation with the Hampton Roads Planning District Commission (HRPDC), to conduct a water-quality monitoring program throughout the Hampton Roads region.

  3. THz identification and Bayes modeling

    Science.gov (United States)

    Sokolnikov, Andre

    2017-05-01

    THz Identification is a developing technology. Sensing in the THz range potentially gives opportunity for short range radar sensing because THz waves can better penetrate through obscured atmosphere, such as fog, than visible light. The lower scattering of THz as opposed to the visible light results also in significantly better imaging than in IR spectrum. A much higher contrast can be achieved in medical trans-illumination applications than with X-rays or visible light. The same THz radiation qualities produce better tomographical images from hard surfaces, e.g. ceramics. This effect comes from the delay in time of reflected THz pulses detection. For special or commercial applications alike, the industrial quality control of defects is facilitated with a lower cost. The effectiveness of THz wave measurements is increased with computational methods. One of them is Bayes modeling. Examples of this kind of mathematical modeling are considered.

  4. 78 FR 14185 - Safety Zone; MODU KULLUK; Kiliuda Bay, Kodiak Island, AK to Captains Bay, Unalaska Island, AK

    Science.gov (United States)

    2013-03-05

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; MODU KULLUK; Kiliuda Bay, Kodiak Island, AK to Captains Bay, Unalaska Island, AK AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY... in Kiliuda Bay, Kodiak Island, Alaska with planned towed transit into Captains Bay, Unalaska Island...

  5. 46 CFR 7.20 - Nantucket Sound, Vineyard Sound, Buzzards Bay, Narragansett Bay, MA, Block Island Sound and...

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Nantucket Sound, Vineyard Sound, Buzzards Bay, Narragansett Bay, MA, Block Island Sound and easterly entrance to Long Island Sound, NY. 7.20 Section 7.20... Atlantic Coast § 7.20 Nantucket Sound, Vineyard Sound, Buzzards Bay, Narragansett Bay, MA, Block Island...

  6. Numerical modelling of oil spill in New York Bay

    Directory of Open Access Journals (Sweden)

    Toz Ali Cemal

    2016-12-01

    Full Text Available New York Bay is one of the most important transition regions of ships trading to east America. The region plays an important role in the commerce of the New York metropolitan area. The area is surrounded with the coasts that have various levels of environmental sensitivity. The area accommodates high diversity of native ecosystems and species that are rather vulnerable in case of oil spill. Thus getting well informed about the likelihood, or fate, of oil spills around this region is of great importance so that proactive measures can be taken. The purpose of this study is to investigate the oil spill and predict the future accidents likely to be encountered around the Bay of New York. Two trajectory models have been conducted for the study. ADIOS (Automated Data Inquiry for Oil Spills, has been conducted for natural degradation calculations, and, GNOME (General NOAA Operational Modeling Environment, has been conducted for surface spread simulation. The results gained through these efforts are hoped to be useful for many organizations dealing with oil spill response operations and contribute to an effective and efficient coordination among the relevant institutions.

  7. Spatial and temporal variability of chlorophyll in Bay of Bengal.

    Science.gov (United States)

    Jutla, A.; Akanda, S.; Islam, S.

    2009-04-01

    The Bay of Bengal (BoB) receives approximately 628 km3/ year of freshwater discharge from the Ganges and Brahmaputra rivers. Freshwater discharge from rivers increases the nutrient load and thereby enhances phytoplankton production in the BoB. Cholera, an infectious water-borne disease caused by bacterium Vibrio cholerae, remains endemic in the BoB region. Phytoplankton provides favorable environment for survival of cholera bacteria. Therefore, for development of any predictive model for cholera, it is important to quantify the spatial and temporal variability of phytoplankton in the BoB. Satellite remote sensing is the most effective way to quantify this variability over a range of space and time scales. Using ten years (1998-2007) of daily, weekly and monthly SeaWiFs chlorophyll, a surrogate variable for measuring phytoplankton, imagery we explore the spatial pattern and dominant temporal variability of chlorophyll over the BoB region. We find that chlorophyll in the coastal waters has more variability, both in temporal and spatial scales, than the offshore waters. Mechanism of production and space-time variability of coastal chlorophyll is different from those of offshore chlorophyll. While coastal chlorophyll is dominated by influx of terrestrial nutrients through river discharge, chlorophyll in the offshore region is primarily controlled by oceanic processes. We will also explore issues related to dominant space and time scales of chlorophyll variations in the entire bay.

  8. Application of remote sensing and GIS in the analysis of environment of Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Patidar, B.

    and the deltaic region of the Ganges-Brahmaputra-Meghna river system, in the east by the Myanmar peninsula and Indonesian archipelago, and in the west by peninsular India and east coasts of Sri Lanka. The southern boundary of the Bay is in contact with southern...

  9. Depth to Transition--Pigeon Point to South Monterey Bay, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the depth-to-transition map of the Pigeon Point to South Monterey Bay, California, region. The raster data file is included in...

  10. EPA Administrator and San Francisco Bay Area government agencies celebrate nations largest solar energy partnership

    Science.gov (United States)

    SAN FRANCISCO - Today, U.S. EPA Administrator Gina McCarthy joined Bay Area agencies to celebrate the Regional Renewable Energy Procurement Project (R-REP), the nation's largest solar energy government collaboration and the launch of the Federal Agg

  11. Atypical ferromanganese micronodules from middle fan-valley system, Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Chauhan, O.S; Gujar, A; Rao, Ch.M.

    Ferromanganese micronodules having botryoidal and spheroidal morphogroups have been observed over a 0.22 million km@u2@@ area from the middle fan region of the Bay of Bengal. The bulk micronodules have 26.26% Mn, 1.02% Fe, 1.82% Ca, 0.12% Ni, 0...

  12. Storm surge in the Bay of Bengal and Arabian Sea: The problem and its prediction

    Digital Repository Service at National Institute of Oceanography (India)

    Dube, S.K.; Rao, A.D.; Sinha, P.C.; Murty, T.S.; Bahulayan, N.

    to annual economic losses in these countries. Thus, the real time monitoring and warning of storm surge is of great concern for this region. The goal of this paper is to provide an overview of major aspects of the storm surge problem in the Bay of Bengal...

  13. Shift in detrital sedimentation in the eastern Bay of Bengal during the ...

    Indian Academy of Sciences (India)

    4. National Centre for Antarctic and Ocean Research, Headland Sada, Vasco 403 804, Goa, India. ∗ e-mail: pbabu@nio.org. Down-core variations of granulometric, geochemical and mineral magnetism of a 70-cm long sedi- ment core retrieved from the eastern Bay of Bengal abyssal region were studied to understand.

  14. Shift in detrital sedimentation in the eastern Bay of Bengal during the ...

    Indian Academy of Sciences (India)

    Abstract. Down-core variations of granulometric, geochemical and mineral magnetism of a 70-cm long sediment core retrieved from the eastern Bay of Bengal abyssal region were studied to understand sedimentation pattern and sediment provenance during the last ∼12 kyr BP. Based on down-core physical and elemental ...

  15. Recent foraminiferal assemblages from the continental shelf sediments of Madras, Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Setty, M.G.A.P.

    During the 15th cruise of INS Kistna, as part of the International Indian Ocean Expedition, several sub-surface samples were collected, (using LaFond-Dietz snapper), from the continental shelf region of the Bay of Bengal. Samples from two locations...

  16. Description of gravity cores from San Pablo Bay and Carquinez Strait, San Francisco Bay, California

    Science.gov (United States)

    Woodrow, Donald L.; John L. Chin,; Wong, Florence L.; Fregoso, Theresa; Jaffe, Bruce E.

    2017-06-27

    Seventy-two gravity cores were collected by the U.S. Geological Survey in 1990, 1991, and 2000 from San Pablo Bay and Carquinez Strait, California. The gravity cores collected within San Pablo Bay contain bioturbated laminated silts and sandy clays, whole and broken bivalve shells (mostly mussels), fossil tube structures, and fine-grained plant or wood fragments. Gravity cores from the channel wall of Carquinez Strait east of San Pablo Bay consist of sand and clay layers, whole and broken bivalve shells (less than in San Pablo Bay), trace fossil tubes, and minute fragments of plant material.

  17. Spatial Variation of Bacteria in Surface Waters of Paranaguá and Antonina Bays, Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    Kolm Hedda Elisabeth

    2002-01-01

    Full Text Available Spatial variability in the concentration of total bacteria, saprophytes and coliforms abundance was investigated in surface waters of Paranaguá and Antonina Bays. Six points along a profile from the entrance of Paranaguá Bay to the innermost part of Antonina Bay, were sampled on February 26, 1997. Temperature, salinity, dissolved oxygen, pH, particulate organic carbon, water transparency and seston were also measured. Determination of total bacterial abundance and biomass were made with the epifluorescent method. Saprophytic bacteria counts were conducted with ZoBell 2216E culture medium with fresh and 32? water and the coliform MPN was enumerated with the chromogenic substrate method. Principal component analysis of biotic and abiotic data showed a gradient from the innermost bay to the baymouth bar with an increase in total and halophobic aerobic cultivated bacteria concentration at Antonina Bay. Greatest values of halophilic aerobic cultivated bacteria were found at the bay?s middle part. The greatest fecal coliform number was observed near Paranaguá City. We concluded that regarding bacterial spatial distribution the outer region of the estuary was highly influenced by the adjacent ocean and that the inner part had typical estuarine characteristics.

  18. A data-derived forecast model of surface currents in a semi-enclosed bay (Yeosu Bay, Republic of Korea)

    Science.gov (United States)

    Won, S. I.; Kim, S. Y.

    2016-02-01

    We present a data-derived surface current forecast model based onobservations of high-frequency radar-derived surface currents, local winds, andalong-track altimeter-derived sea surface height anomalies off the southern coastof Korea (Yeosu Bay). The coastal surface circulation in this region is decomposedinto tide-, wind-, pressure gradient-coherent components depending on their forcingmechanisms in a hind cast model. The data-derived forecast model consistsof tidal harmonic analysis, response functions using wind stress and pressuregradients, and autoregressive process for residuals, These basis functions wereconsecutively added, and the performance of the forecast model is evaluated.

  19. Tectonic Origin of the 1899 Yakutat Bay Earthquakes, Alaska, and Insights into Future Hazards

    Science.gov (United States)

    Gulick, S. S.; LeVoir, M. A.; Haeussler, P. J.; Saustrup, S.

    2012-12-01

    On September 10th the largest of four earthquakes (Mw 8.2) that occurred in southeast Alaska on 1899 produced a 6 m tsunami and may have produced as much as 14 m of co-seismic uplift. This earthquake had an epicenter somewhere near Yakutat or Disenchantment Bays. These bays lie at the transition between the Fairweather Fault (the Pacific-North American strike-slip plate boundary), and the Yakutat Terrane-North American subduction zone. The deformation front of this subduction zone is thought to include the eastern fault in the Pamplona Zone offshore, the Malaspina Fault onshore, and the Esker Creek Fault near Yakutat Bay. The 10 September 1899 event could have taken place on a Yakutat-North American megathrust that daylights in Yakutat or Disenchantment Bay. Alternatively, the 10 September 1899 earthquake could have originated from the Fairweather-Boundary and Yakutat faults, transpressive components of the Fairweather strike-slip system present in the Yakutat Bay region, or from thrusting along the Yakutat and Otemaloi Faults on the southeast flank of Yakutat Bay. Characterizing fault slip during the Alaskan earthquakes of 1899 is vital to assessing both subduction zone structure and seismic hazards in the Yakutat Bay area. Each possible fault model has a different implication for modern hazards. These results will be used to update seismic hazard and fault maps and assess future risk to the Yakutat Bay and surrounding communities. During Aug. 6-17th, we anticipate acquiring high-resolution, marine multichannel seismic data aboard the USGS vessel Alaskan Gyre in Yakutat and Disenchantment Bays to search for evidence of recent faulting and directly test these competing theories for the 10 September 1899 event. This survey uses the University of Texas Institute for Geophysics' mini-GI gun, 24-channel seismic streamer, portable seismic compressor system, and associated gun control and data acquisition system to acquire the data. The profiles have a nominal common

  20. FL BAY SPECTROUT-POPULATION STATUS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Juvenile spotted seatrout and other sportfish are being monitored annually over a 6-mo period in Florida Bay to assess their abundance over time relative to...

  1. Watermass structure in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Sastry, J.S.; Rao, D.P.; Murty, V.S.N.; Sarma, Y.V.B.; Suryanarayana, A.; Babu, M.T.

    The distributions of temperature, salinity thermosteric anomaly, density flux function and stability along 88 degrees E in the Bay of Bengal are presented. The surface salinities showed strong gradients both horizontally and vertically in northern...

  2. Delaware River and Upper Bay Sediment Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The area of coverage consists of 192 square miles of benthic habitat mapped from 2005 to 2007 in the Delaware River and Upper Delaware Bay. The bottom sediment map...

  3. Underwater Video Sites in Jobos Bay

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Shallow-water (<30m) benthic habitat maps of the nearshore marine environment of Jobos Bay, Puerto Rico were mapped and characterized using visual interpretation...

  4. San Antonio Bay 1986-1989

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The effect of salinity on utilization of shallow-water nursery habitats by aquatic fauna was assessed in San Antonio Bay, Texas. Overall, 272 samples were collected...

  5. BENTHIC MACROFAUNAL ALIENS IN WILLAPA BAY

    Science.gov (United States)

    Benthic macrofaunal samples were collected at random stations in Willapa Bay, WA, in four habitats [eelgrass (Zostera marina), Atlantic cordgrass (Spartina alterniflora), mud shrimp (Upogebia pugettensis), ghost shrimp (Neotrypaea californiensis)] in 1996 and in seven habitats (Z...

  6. Bay Scallop Spawning, Survival, Growth Records

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bay Scallops are selected and cultured according to criteria of growth and survival. Morphological attributes have also been selected to assess heretibility....

  7. Mesozoic anomalies in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Ramana, M.V.; Nair, R.R.; Sarma, K.V.L.N.S.; Ramprasad, T.; Krishna, K.S.; Subrahmanyam, V.; D'Cruz, M.; Subrahmanyam, C.; Paul, J.; Subrahmanyam, A.S.; Sekhar, D.V.C.

    The analysis of 8200 line km of total magnetic intensity data in the Bay of Bengal, northeastern Indian Ocean, revealed the presence of approximately N30~'E-trending seafloor spreading type magnetic anomalies. These anomalies resemble the Mesozoic...

  8. 2002 Willapa Bay LiDAR Project

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA contracted with Spencer B. Gross, Inc. (SBG) to obtain airborne LiDAR of Willapa Bay, Washington during low tide conditions. The LiDAR data was processed to...

  9. Corpus ChristiEast Matagorda Bay 1986

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Patterns of habitat utilization were compared among transplanted and natural Spartina alterniflora marshes in the Halls Lake area of Chocolate Bay in the Galveston...

  10. 2004 Saginaw Bay, Lake Huron, Michigan Lidar

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This metadata document describes the collection and processing of Light Detection and Ranging (LIDAR) data over an area along the coast of Saginaw Bay, Lake Huron,...

  11. Willapa Bay, Washington Benthic Habitats 1995 Biotic

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In June 1995, the Columbia River Estuary Study Taskforce (CREST) acquired 295 true color aerial photographs (1:12,000) of Willapa Bay, Washington, from the State of...

  12. Willapa Bay, Washington Benthic Habitats 1995 Geoform

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In June 1995, the Columbia River Estuary Study Taskforce (CREST) acquired 295 true color aerial photographs (1:12,000) of Willapa Bay, Washington, from the State of...

  13. Willapa Bay, Washington Benthic Habitats 1995 Substrate

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In June 1995, the Columbia River Estuary Study Taskforce (CREST) acquired 295 true color aerial photographs (1:12,000) of Willapa Bay, Washington, from the State of...

  14. Wastewater Out Front in Bay Restoration

    Science.gov (United States)

    Clean Water Act programs administered by EPA and the delegated states have played a central role in the success of the wastewater sector in effectively meeting nutrient limits in the Chesapeake Bay “pollution diet” a decade early.

  15. Biscayne Bay Florida Bottlenose Dolphin Studies

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data sets include a compilation of small vessel based studies of bottlenose dolphins that reside within Biscayne Bay, Florida, adjacent estuaries and nearshore...

  16. South Bay Salt Ponds : Initial stewardship plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The California Department of Fish and Game and the U.S. Fish and Wildlife Service will operate and maintain the South Bay Salt Ponds under this Initial Stewardship...

  17. Back Bay National Wildlife Refuge: Master Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Back Bay National Wildlife Refuge, located in the city of Virginia Beach, Virginia, comprises 4,608 acres of barrier beach, fresh and brackish marsh, small...

  18. Historical methyl mercury in San Francisco Bay

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — San Francisco Bay, California is considered a mercury-impaired watershed. Elevated concentrations of mercury are found in water and sediment as well as fish and...

  19. Naive Bayes Image Classification: beyond Nearest Neighbors

    OpenAIRE

    Timofte, Radu; Tuytelaars, Tinne; Van Gool, Luc

    2012-01-01

    Timofte R., Tuytelaars T., Van Gool L., ''Naive bayes image classification: beyond nearest neighbors'', 11th Asian conference on computer vision - ACCV 2012, 13 pp., November 5-9, 2012, Daejeon, Korea.

  20. Saginaw Bay Restoration Assessment Degree Flowlines

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This represents the flowline network in Sagina Bay Restoration Assessment (SBRA). It is attributed with the number of disconnections between the reach and the...

  1. Willapa Bay, Washington Benthic Habitats 1995 Geodatabase

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In June 1995, the Columbia River Estuary Study Taskforce (CREST) acquired 295 true color aerial photographs (1:12,000) of Willapa Bay, Washington, from the State of...

  2. The surface heat budget of Hudson Bay

    National Research Council Canada - National Science Library

    Danielson, E.W

    1969-01-01

    ... which information the heat budget calculations are based. These data include surface air and sea temperatures, ice concentration, cloudiness, wind, atmospheric moisture, ice and water movement, and heat storage amounts within Hudson Bay waters...

  3. Differential productivity of Bristol Bay spawning grounds

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Bristol Bay escapement surveys covering a period of several years show that, irrespective of fluctuations in total numbers on a system, certain grounds display a...

  4. On the Shrimp Fauna of Kozima Bay in the Seto Inland Sea

    OpenAIRE

    小川, 泰樹; 角田, 俊平; 高橋, 正雄

    1983-01-01

    A study was carried out to clarify the shrimp fauna of Kozima Bay (brackish water) in the Seto Inland Sea, and to compare it with those of Lake Kozima (fresh water) and the coastal region (salt water) near Kozima Bay. The shrimp specimens were collected 6 times over a period of one year every other month from September of 1976 to August of '77 with a small trawl net. Thc number of shrimps collected was 4,208 and they were classified into 15 species belonging to 3 families. Of these, 5 species...

  5. Hurricane Ike Deposits on the Bolivar Peninsula, Galveston Bay, Texas

    Science.gov (United States)

    Evans, Cynthia A.; Wilkinson, M. J.; Eppler, Dean

    2011-01-01

    In September 2008, Hurricane Ike made landfall on Galveston Bay, close to the NASA Johnson Space Center (JSC). The storm flooded much of the area with a storm surge ranging from 11 -20 feet. The Bolivar peninsula, the southeastern coast of Galveston Bay, experienced the brunt of the surge. Several agencies collected excellent imagery baselines before the storm and complementary data a few days afterward that helped define the impacts of the storm. In April of 2011, a team of scientists and astronauts from JSC conducted field mapping exercises along the Bolivar Peninsula, the section of the Galveston Bay coast most impacted by the storm. Astronauts routinely observe and document coastal changes from orbit aboard the International Space Station. As part of their basic Earth Science training, scientists at the Johnson Space Center take astronauts out for field mapping exercises so that they can better recognize and understand features and processes that they will later observe from the International Space Station. Using pre -storm baseline images of the Bolivar Peninsula near Rollover Pass and Gilchrist (NOAA/Google Earth Imagery and USGS aerial imagery and lidar data), the astronauts mapped current coastline positions at defined locations, and related their findings to specific coastal characteristics, including channel, jetties, and other developments. In addition to mapping, we dug trenches along both the Gulf of Mexico coast as well as the Galveston Bay coast of the Bolivar peninsula to determine the depth of the scouring from the storm on the Gulf side, and the amount of deposition of the storm surge deposits on the Bay side of the peninsula. The storm signature was easy to identify by sharp sediment transitions and, in the case of storm deposits, a layer of storm debris (roof shingles, PVC pipes, etc) and black, organic rich layers containing buried sea grasses in areas that were marshes before the storm. The amount of deposition was generally about 20 -25 cm

  6. Hurricane Ike Deposits on the Bolivar Peninsula, Galveston Bay, Texas

    Science.gov (United States)

    Evans, C. A.; Wilkinson, M. J.; Eppler, D.

    2011-12-01

    In September 2008, Hurricane Ike made landfall on Galveston Bay, close to the NASA Johnson Space Center (JSC). The storm flooded much of the area with a storm surge ranging from 11-20 feet. The Bolivar peninsula, the southeastern coast of Galveston Bay, experienced the brunt of the surge. Several agencies collected excellent imagery baselines before the storm and complementary data a few days afterward that helped define the impacts of the storm. In April of 2011, a team of scientists and astronauts from JSC conducted field mapping exercises along the Bolivar Peninsula, the section of the Galveston Bay coast most impacted by the storm. Astronauts routinely observe and document coastal changes from orbit aboard the International Space Station. As part of their basic Earth Science training, scientists at the Johnson Space Center take astronauts out for field mapping exercises so that they can better recognize and understand features and processes that they will later observe from the International Space Station. Using pre-storm baseline images of the Bolivar Peninsula near Rollover Pass and Gilchrist (NOAA/Google Earth Imagery and USGS aerial imagery and lidar data), the astronauts mapped current coastline positions at defined locations, and related their findings to specific coastal characteristics, including channel, jetties, and other developments. In addition to mapping, we dug trenches along both the Gulf of Mexico coast as well as the Galveston Bay coast of the Bolivar peninsula to determine the depth of the scouring from the storm on the Gulf side, and the amount of deposition of the storm surge deposits on the Bay side of the peninsula. The storm signature was easy to identify by sharp sediment transitions and, in the case of storm deposits, a layer of storm debris (roof shingles, PVC pipes, etc) and black, organic rich layers containing buried sea grasses in areas that were marshes before the storm. The amount of deposition was generally about 20-25 cm; the

  7. Bathymetry and digital elevation models of Coyote Creek and Alviso Slough, South San Francisco Bay, California

    Science.gov (United States)

    Foxgrover, Amy C.; Finlayson, David P.; Jaffe, Bruce E.; Fregoso, Theresa A.

    2011-01-01

    In 2010 the U.S. Geological Survey (USGS), Coastal and Marine Geology Program completed three cruises to map the bathymetry of the main channel and shallow intertidal mudflats in the southernmost part of south San Francisco Bay. The three surveys were merged to generate comprehensive maps of Coyote Creek (from Calaveras Point east to the railroad bridge) and Alviso Slough (from the bay to the town of Alviso) to establish baseline bathymetry prior to the breaching of levees adjacent to Alviso and Guadalupe Sloughs as part of the South Bay Salt Pond Restoration Project http://www.southbayrestoration.org. Since 2010 we have conducted four additional surveys to monitor bathymetric change in this region as restoration progresses.

  8. Multivariate and geo-spatial approach for seawater quality of Chidiyatappu Bay, south Andaman Islands, India.

    Science.gov (United States)

    Jha, Dilip Kumar; Vinithkumar, Nambali Valsalan; Sahu, Biraja Kumar; Dheenan, Palaiya Sukumaran; Das, Apurba Kumar; Begum, Mehmuna; Devi, Marimuthu Prashanthi; Kirubagaran, Ramalingam

    2015-07-15

    Chidiyatappu Bay is one of the least disturbed marine environments of Andaman & Nicobar Islands, the union territory of India. Oceanic flushing from southeast and northwest direction is prevalent in this bay. Further, anthropogenic activity is minimal in the adjoining environment. Considering the pristine nature of this bay, seawater samples collected from 12 sampling stations covering three seasons were analyzed. Principal Component Analysis (PCA) revealed 69.9% of total variance and exhibited strong factor loading for nitrite, chlorophyll a and phaeophytin. In addition, analysis of variance (ANOVA-one way), regression analysis, box-whisker plots and Geographical Information System based hot spot analysis further simplified and supported multivariate results. The results obtained are important to establish reference conditions for comparative study with other similar ecosystems in the region. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Hydrodynamic properties of San Quintin Bay, Baja California: Merging models and observations.

    Science.gov (United States)

    Melaku Canu, Donata; Aveytua-Alcázar, Leslie; Camacho-Ibar, Victor F; Querin, Stefano; Solidoro, Cosimo

    2016-07-15

    We investigated the physical dynamics of San Quintin Bay, a coastal lagoon located on the Pacific coast of northern Baja California, Mexico. We implemented, validated and used a finite element 2-D hydrodynamic model to characterize the spatial and temporal variability of the hydrodynamic of the bay in response to variability in the tidal regime and in meteorological forcing patterns. Our analysis of general circulation, residual currents, residence times, and tidal propagation delays allowed us to characterize spatial variability in the hydrodynamic basin features. The eulerian water residence time is -on average and under reference conditions- approximately 7days, although this can change significantly by region and season and under different tidal and meteorological conditions. Ocean upwelling events that bring colder waters into the bay mouth affect hydrodynamic properties in all areas of the lagoon and may affect ecological dynamics. A return to pre-upwelling conditions would take approximately 10days. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Imposex and surface sediment speciation: a combined approach to evaluate organotin contamination in Guanabara Bay, Rio de Janeiro, Brazil.

    Science.gov (United States)

    Fernandez, M A; de Luca Rebello Wagener, A; Limaverde, A M; Scofield, A L; Pinheiro, F M; Rodrigues, E

    2005-06-01

    An integrated biological-chemical survey of organotin compounds was carried out in Guanabara Bay, the second most important Brazilian harbor complex. The biological survey revealed high levels of imposex in Stramonita haemastoma populations. Inside the bay values of relative penis length index from 42.7 to 107.6 and vas deferens sequence index from III to VI were found, while organisms collected outside the bay had values ranging from imposex was found in all stations. Surface sediments in the bay are contaminated by tributyltin (10-522 ng/g d.w.) and triphenyltin (imposex-sediment approach to evaluate organotin contamination in marine environments of South America, and also the first report of TPT detection in environmental matrices in this region.

  11. Net-zooplankton abundance and biomass from Annaba Bay (SW Mediterranean Sea under estuarine influences

    Directory of Open Access Journals (Sweden)

    M. OUNISSI

    2016-07-01

    Full Text Available Zooplankton samples were collected in Annaba Bay (Algeria from January 2009-March 2011 at three coastal sites differently affected by estuarine plumes and external currents. Aim of this survey was to analyze zooplankton composition, abundance and biomass and compare the results with previous studies to reveal possible populations and environmental changes. The mean zooplankton abundance varied between 1,200-6,000 ind. m-3 and biomass 6.70-25.70 mg DW m-3, according to the site. Copepods constituted the main fraction of zooplankton community, and Oithona similis and Paracalanus indicus successively dominated during autumn-winter and spring-summer. The dinoflagellate Noctiluca scintillans was one of the major zooplankton components, and developed high numbers during February-April, becoming common in neritic and coastal regions. The singularity of the zooplankton from Annaba Bay is the prevalence of P. indicus throughout the entire bay and the decrease in Acartia discaudata and A. clausi (with respect to previous years, possibly replaced by A. negligens. Additionally, Oithona nana abundance markedly decreased with the large development of O. similis. Annaba Bay also differs from other similar Mediterranean coastal areas by the large development of Centropages ponticus populations during the warm period. Among the identified copepod species, the alien species Pseudodiaptomus australiensis and P. arabicus are reported for the first time in the Mediterranean Sea. The occurrence of copepodid V stages of P. australiensis suggests that this species survives and reproduces in Annaba Bay, but so far without developing an abundant population.

  12. Disease dynamics of Montipora white syndrome within Kaneohe Bay, Oahu, Hawaii: distribution, seasonality, virulence, and transmissibility.

    Science.gov (United States)

    Aeby, G S; Ross, M; Williams, G J; Lewis, T D; Works, T M

    2010-07-26

    We report on an investigation of Montipora white syndrome (MWS), which is a coral disease reported from Hawaii, U.S.A., that results in tissue loss. Disease surveys of Montipora capitata within Kaneohe Bay (Oahu) found colonies that were affected by MWS on 9 reefs within 3 regions of Kaneohe Bay (south, central, north). Mean MWS prevalence ranged from 0.02 to 0.87% and average number of MWS cases per survey site ranged from 1 to 28 colonies. MWS prevalence and number of cases were significantly lower in the central region as compared to those in the north and south regions of Kaneohe Bay. There was a positive relationship between host abundance and MWS prevalence, and differences in host abundance between sites explained approximately 27% of the variation in MWS prevalence. Reefs in central Kaneohe Bay had lower M. capitata cover and lower MWS levels. MWS prevalence on reefs was neither significantly different between seasons (spring versus fall) nor among 57 tagged colonies that were monitored through time. MWS is a chronic and progressive disease causing M. capitata colonies to lose an average of 3.1% of live tissue mo(-1). Case fatality rate was 28% after 2 yr but recovery occurred in some colonies (32%). Manipulative experiments showed that the disease is acquired through direct contact. This is the first study to examine the dynamics of MWS within Hawaii, and our findings suggest that MWS has the potential to degrade Hawaii's reefs through time.

  13. Eddies in the Bay of Biscay: A numerical approximation

    Science.gov (United States)

    Ferrer, Luis; Caballero, Ainhoa

    2011-08-01

    The results of numerical modelling in the Bay of Biscay have been used to investigate eddy dynamics. The modelling has been carried out using mean climatological and atmospheric forcing as input for hydrodynamic simulations with the ROMS model (Regional Ocean Modeling System). The most significant regional circulation features have been simulated in a mesoscale model configuration, with 6.6 km horizontal resolution. Eddy characteristics (horizontal and vertical structure, origins and migration) have been analysed. During winter, jet-like extensions of the slope current off northern Spain (mainly in the vicinity of Cape Ortegal) and France (near Cap Breton, Cap Ferret and Audierne canyons) developed into anticyclonic and cyclonic eddies, with an upper core of slope water. Most of the eddies identified in the model area were anticyclonic, with diameters at sea surface of between 60 and 130 km and significant effects below 500 m in depth. After their generation, the eddies moved slowly westward, with a mean migration speed of less than 2 cm s -1; they dissipated later in the year in the deep basin of the Bay of Biscay. The mean annual surface kinetic energy, estimated with the model, was around 34 cm 2 s -2. Both the kinetic energy and vorticity variability in the study area depend upon changes (magnitude and direction) in the wind stress, which have effects on the development of: the slope poleward current; the Galician upwelling; and the eddy generation and migration.

  14. 77 FR 2972 - Thunder Bay Power Company, Thunder Bay Power, LLC, et al.

    Science.gov (United States)

    2012-01-20

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Thunder Bay Power Company, Thunder Bay Power, LLC, et al.; Notice of..., 2347-049, 2373-010 Midwest Hydro, LLC Midwest Hydraulic Company, Inc Project No. 10805-054 Midwest...

  15. BOOK REVIEW OF "CHESAPEAKE BAY BLUES: SCIENCE, POLITICS, AND THE STRUGGLE TO SAVE THE BAY"

    Science.gov (United States)

    This is a book review of "Chesapeake Bay Blues: Science, Politics, and the Struggle to Save the Bay". This book is very well written and provides an easily understandable description of the political challenges faced by those proposing new or more stringent environmental regulat...

  16. Influenza in Bristol Bay, 1919

    Directory of Open Access Journals (Sweden)

    Maria Gilson deValpine

    2015-03-01

    Full Text Available The 1918 influenza pandemic has been blamed for as many as 50 million deaths worldwide. Like all major disasters, the full story of the pandemic includes smaller, less noted episodes that have not attracted historical attention. The story of the 1919 wave of the influenza pandemic in Bristol Bay Alaska is one such lost episode. It is an important story because the most accessible accounts—the Congressional Record and the Coast Guard Report—are inconsistent with reports made by employees, health care workers, and volunteers at the site of the disaster. Salmon fishing industry supervisors and medical officers recorded their efforts to save the region’s Native Alaskans in private company reports. The federal Bureau of Education physician retained wireless transmission, reports, and letters of events. The Coast Guard summarized its work in its Annual Report of 1920. The independent Bureau of Fisheries report to the Department of Commerce reveals the Coast Guard report at striking odds with others and reconciles only one account. This article explores the historical oversight, and attempts to tell the story of the 1919 wave of the pandemic which devastated the Native Alaskan population in this very remote place.

  17. Biological response to local and remote forcing in the bay of Bengal

    Science.gov (United States)

    Gomes, Helga; Goes, Joaquim; deRada, Sergio; Thoppil, Prasad; Matondkar, Prabhu

    2014-05-01

    The permanently stratified water column in the Bay of Bengal and a strong halocline, resulting from a heavy influx of freshwater from river runoff and precipitation is an impediment to mixing processes that can inject new nutrients into the bay. Consequently, unlike the monsoonal blooms of the Arabian Sea with rates of primary productivity exceptional in magnitude among offshore ocean regions, phytoplankton productivity in the Bay of Bengal is modest and largely dependent on processes that can erode the halocline and entrain nutrients into the euphotic zone. Although considerable advances have been made in understanding the physical mechanisms that are particularly unique to the Bay of Bengal such as the Sri Lanka and Bay of Bengal Domes during the Southwest monsoon, mixing induced by tropical cyclones and cyclonic eddies, all of which can bring new nutrients into the euphotic zone, there seems to be little understanding of the biological response. This is a consequence of sparse shipboard biological measurements of phytoplankton biomass and productivity and inadequate coverage of ocean color satellite measurements because of persistent cloud cover. In view of these limitations, ecosystem models are more advantageous as they offer large scale coverage even under cloudy conditions as well as over the euphotic depth an important aspect for studying the deep chlorophyll maxima. In this study we use outputs from a Naval Coastal Ocean Model (NCOM) coupled to a 13-component ecosystem model to describe some of the unique physical forcing features of the Bay of Bengal which enhance phytoplankton productivity in an otherwise low productivity environment. Model results are compared and evaluated against in-situ and remotely sensed observations. We focus on three physically and biologically active regions viz. the Sri Lanka Dome during the Southwest monsoon followed by the Bay of Bengal Dome to its north and the winter bloom in the southwest of the bay. Using the model

  18. A late Holocene palaeoenvironmental record from Altona Bay, St. Croix, US Virgin Islands

    DEFF Research Database (Denmark)

    Jessen, C.A.; Pedersen, Jørn Bjarke Torp; Bartholdy, Jesper

    2008-01-01

    . The sedimentary sequence covers the last c. 4700 years, containing both (mangrove) peat and fine-grained clastic sediment units. Comparison with regional Holocene sea level data demonstrates a gradual marine flooding of a mangrove environment around 3500 cal BP was presumably related to a regional late Holocene...... of the bay and have caused a major hiatus and the recent deposition of sediments immediately overlying the c. 2500 year old peat....

  19. Gulf of Mexico Integrated Science - Tampa Bay Study - Historical and Prehistorical Record of Tampa Bay Environments

    Science.gov (United States)

    Edgar, Terry

    2005-01-01

    To study how Tampa Bay, Florida, has changed over time, the prehistorical conditions and natural variations in the bay environment are being evaluated. These variations can be tracked by examining the sediments that have accumulated in and around the bay. The prehistorical record, which pre-dates settlers' arrival in the Tampa Bay area around 1850, provides a baseline with which to compare and evaluate the magnitude and effects of sea-level, climate, biological, geochemical, and man-made changes. These data also are valuable for planning and conducting projects aimed at restoring wetlands and other estuarine habitats to their original state. In addition, the data provide a basis for judging efforts to improve the health of the bay.

  20. 76 FR 23193 - Traffic Separation Schemes: In the Approaches to Portland, ME; Boston, MA; Narragansett Bay, RI...

    Science.gov (United States)

    2011-04-26

    ... Portland, ME; Boston, MA; Narragansett Bay, RI and Buzzards Bay, MA; Chesapeake Bay, VA, and Cape Fear... Portland, ME; in the approaches to Boston, MA; in the approaches to Narragansett Bay, RI and Buzzards Bay... Portland, ME; Boston, MA; Narragansett Bay, RI and Buzzards Bay, MA; Chesapeake Bay, VA; and Cape Fear...

  1. Response of Harmful Algal Blooms to Environmental Changes in Daya Bay, China

    Directory of Open Access Journals (Sweden)

    Jing Yu

    2007-01-01

    Full Text Available Economic progress has been rapid around the Daya Bay region of the northern South China Sea (SCS over recent decades. To investigate changes of Harmful Algal Blooms (HABs caused by environmental situation in the bay area, the present study analyzed the occurrence of HAB and environmental conditions in Daya Bay using in situ and satellite remote sensing data for the period of 1983 - 2004. Only 14 HABs were observed during the first decade (1983 - 1993, while 55 HABs occurred during the second decade (1994 - 2004. The locations of HAB have extended from aquaculture areas to the entire bay area. In addition, the seasonality of HAB has changed from spring and autumn prior to 1994 to all year round post 1994. Changes in HAB frequency and location were found to be associated with variations in nutrients and contaminants in the bay area. Total inorganic nitrogen (TIN was 0.021 mg l -1 in 1986, but had reached 0.068 mg l -1 by 1999 and the ratio of TIN/P increased also, with a peak value (18.28 in 1999. Organic contaminants have also been relatively high in recent years in Daya Bay. The seasonal extension of HAB was found to be connected partially with increased water temperature resulting from the thermal discharge of nuclear power stations. Yearly mean water surface temperature (WST increased over the past two decades. Monthly mean WST also increased after the Daya Bay nuclear power station commenced operating in 1994, ranging from 0.2 to 2.7¢XC. There were about 14 algal species recorded to have caused HABs frequently in Daya Bay, such as Scrippsiella trochoidea. The number of HAB species increased in the second decade (1994 - 2004. A warm-water favoring species Peridinium quinquecorne caused a bloom in May 1999. This was the first recorded time of this species blooming in China. These changes are associated with increases in cage aquaculture, contaminants discharged from industrial and agricultural activities, and thermal discharge from the nuclear

  2. Deep Drilling into the Chesapeake Bay Impact Structure

    Science.gov (United States)

    Gohn, G. S.; Koeberl, C.; Miller, K. G.; Reimold, W. U.; Browning, J. V.; Cockell, C. S.; Horton, J. W.; Kenkmann, T.; Kulpecz, A. A.; Powars, D. S.; Sanford, W. E.; Voytek, M. A.

    2008-06-01

    Samples from a 1.76-kilometer-deep corehole drilled near the center of the late Eocene Chesapeake Bay impact structure (Virginia, USA) reveal its geologic, hydrologic, and biologic history. We conducted stratigraphic and petrologic analyses of the cores to elucidate the timing and results of impact-melt creation and distribution, transient-cavity collapse, and ocean-water resurge. Comparison of post-impact sedimentary sequences inside and outside the structure indicates that compaction of the crater fill influenced long-term sedimentation patterns in the mid-Atlantic region. Salty connate water of the target remains in the crater fill today, where it poses a potential threat to the regional groundwater resource. Observed depth variations in microbial abundance indicate a complex history of impact-related thermal sterilization and habitat modification, and subsequent post-impact repopulation.

  3. Wind Atlas of Bay of Bengal with Satellite Wind Measurement

    DEFF Research Database (Denmark)

    Nadi, Navila Rahman

    The objective of this study is to obtain appropriate offshore location in the Bay of Bengal, Bangladesh for further development of wind energy. Through analyzing the previous published works, no offshore wind energy estimation has been found here. That is why, this study can be claimed as the first...... footstep towards offshore wind energy analysis for this region. Generally, it is difficult to find offshore wind data relative to the wind turbine hub heights, therefore a starting point is necessary to identify the possible wind power density of the region. In such scenario, Synthetic aperture radars (SAR......) have proven useful. In this study, SAR based dataset- ENVISAT ASAR has been used for Wind Atlas generation. Furthermore, a comparative study has been performed with Global Wind Atlas (GWA) to determine a potential offshore wind farm. Additionally, the annual energy production of that offshore windfarm...

  4. Radium isotopes in the Ulsan Bay

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Seong [Department of Oceanography, Chungnam National University, Gung-dong 220, Yuseong, Daejeon 305-764 (Korea, Republic of)]. E-mail: leejs728@nfrda.re.kr; Kim, Kee Hyun [Department of Oceanography, Chungnam National University, Gung-dong 220, Yuseong, Daejeon 305-764 (Korea, Republic of); Moon, Duck Soo [Department of Oceanography, Chungnam National University, Gung-dong 220, Yuseong, Daejeon 305-764 (Korea, Republic of)

    2005-07-01

    In order to estimate the fluxes of Ra isotopes, we measured {sup 224}Ra, {sup 226}Ra, and {sup 228}Ra activities in the Ulsan Bay mixing zone. The convex upwards curvature of the plot of Ra isotope activities versus salinity for the mixing zone suggests that Ra isotopes are supplied from particles entering the mixing zone from both the river and bottom sediments. This addition increases the estuarine flux of {sup 226}Ra and {sup 228}Ra to the outer sea by factors of 15 and 95 over the flux attributable to Ra dissolved in the riverine water alone. In order to estimate the residence time of the water in Ulsan Bay, we applied a mass balance model to the distribution of {sup 224}Ra and {sup 226}Ra activities in the Ulsan Bay mixing zone with the inflow from the Taehwa River. The obtained residence times of the waters in the Ulsan Bay were estimated to be 6.8-11.4 d. The waters in the upper part of the estuary have long residence times whereas those in the lower part, in contact with the open sea, have shorter residence times. The mean residence time of the water in the Ulsan Bay was estimated to be 9.1 d.

  5. Multi-GPGPU Tsunami simulation at Toyama-bay

    Science.gov (United States)

    Furuyama, Shoichi; Ueda, Yuki

    2017-07-01

    Accelerated multi General Purpose Graphics Processing Unit (GPGPU) calculation for Tsunami run-up simulation was achieved at the wide area (whole Toyama-bay in Japan) by faster computation technique. Toyama-bay has active-faults at the sea-bed. It has a high possibility to occur earthquakes and Tsunami waves in the case of the huge earthquake, that's why to predict the area of Tsunami run-up is important for decreasing damages to residents by the disaster. However it is very hard task to achieve the simulation by the computer resources problem. A several meter's order of the high resolution calculation is required for the running-up Tsunami simulation because artificial structures on the ground such as roads, buildings, and houses are very small. On the other hand the huge area simulation is also required. In the Toyama-bay case the area is 42 [km] × 15 [km]. When 5 [m] × 5 [m] size computational cells are used for the simulation, over 26,000,000 computational cells are generated. To calculate the simulation, a normal CPU desktop computer took about 10 hours for the calculation. An improvement of calculation time is important problem for the immediate prediction system of Tsunami running-up, as a result it will contribute to protect a lot of residents around the coastal region. The study tried to decrease this calculation time by using multi GPGPU system which is equipped with six NVIDIA TESLA K20xs, InfiniBand network connection between computer nodes by MVAPICH library. As a result 5.16 times faster calculation was achieved on six GPUs than one GPU case and it was 86% parallel efficiency to the linear speed up.

  6. Typology of hydrological structures modelled and observed over the Bay of Biscay shelf

    Directory of Open Access Journals (Sweden)

    Benjamin Planque

    2006-06-01

    Full Text Available Collecting hydrological observations over the whole Bay of Biscay continental shelf can require several weeks. As a result, the observations are not truly synoptic and the interpretation of hydrological structures is corrupted by the time-lags between observations at distinct locations. We evaluated the effects of non-synoptic sampling during a spring cruise (17 April to 13 May 2000, using outputs from 3D hydrodynamic models as a substitute for true synoptic sampling. We developed a method for clustering hydrological regions based on the vertical structure of the water column and temporal changes in hydrography. In parallel, outputs from the 3D model were compared with field observations. The results show that in spring 2000 the Bay of Biscay continental shelf could be separated into six principal hydrological regions, one of them being characterised by vertical stability and low temporal variability. This region corresponds to an area where pelagic fish spawning activity is known to be persistently low.

  7. Strategy of Developing Tomini Bay for Economic Growth of Coastal Community in Central Sulawesi

    Directory of Open Access Journals (Sweden)

    Muzakir Muzakir

    2016-06-01

    Full Text Available This research aims to analyze the potential and the strategy of developing Tomini Bay to improve the economic growth of the coastal community in Central Sulawesi. The research is located in four regencies in Central Sulawesi. The method uses the descriptive analysis using SWOT analysis. The research result shows that the potential of fisheries resources in Poso Regency, Parigi Moutong Regency, Tojo Una-Una Regency, and Banggai Regency can support the development of Tomini Bay region based on fisheries in order to accelerate the economic growth of coastal communities in Central Sulawesi. The potential fishery resources that can support the development of Tomini Bay area are the potential of fisheries, marine and coastal infrastructure, social economy and geographic conditions in four regencies. The strategies are building the marketing network for fishery products both the catching and cultivation, improving the fishery human resouce capacity, controlling the fishery product quality, and increasing the social awareness to maintain the ecosystem sustainability. To optimize the utilization of Tomini Bay, it is suggested to improve the involvement of the regional government, the central government, and also the private sector and the whole community.

  8. Sediment dynamics of a sediment-starved, open-marine marsh embayment: Waccasassa Bay, Florida

    Science.gov (United States)

    Wood, Nathan J.; Hine, Albert C.

    2003-01-01

    Although the Big Bend region of Florida's Gulf of Mexico coast is considered sediment-starved, the open marine marshes that characterize the area are keeping pace with sea level rise. Waccasassa Bay, an embayment within this region, also contains unique subtidal mudbanks that thicken with increasing proximity to embayment head, while the remainder of the bayfloor is characterized by exposed carbonate bedrock or by a thin veneer of sediment. Hydro- dynamic data sets were collected to determine the primary sedimentary processes within Waccasassa Bay capable of creating such geomorphic features. Data suggest that the embayment is a flood-dominated system influenced primarily by semi-diurnal tides with flood-stage intensification towards the river-mouth. Subtidal mudbanks are believed to be the result of tidal time-velocity asymmetries and the convergence of sediment transport pathways. Flood dominance for potential bedload transport suggests a gradual infilling of the bay interior for the short time scale of this study. With no mechanism for seaward transport, Waccasassa Bay can be considered a sediment sink for the remainder of the Big Bend re

  9. Fishery Management Program Progress Report: Back Bay National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Memorandum containing summary of fishery biologist's visit to Back Bay to remove carp from impoundments at Back Bay National Wildlife Refuge.

  10. Parameter Identification by Bayes Decision and Neural Networks

    DEFF Research Database (Denmark)

    Kulczycki, P.; Schiøler, Henrik

    1994-01-01

    The problem of parameter identification by Bayes point estimation using neural networks is investigated.......The problem of parameter identification by Bayes point estimation using neural networks is investigated....

  11. SF Bay Water Quality Improvement Fund: Projects and Accomplishments

    Science.gov (United States)

    San Francisco Bay Water Quality Improvement Fund (SFBWQIF) projects listed here are part of an EPA competitive grant program to improve SF Bay water quality focused on restoring impaired waters and enhancing aquatic resources.

  12. Benthic grab data from October 1999 in Apalachicola Bay, Florida

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Apalachicola Bay National Estuarine Research Reserve and the NOAA Office for Coastal Management worked together to map benthic habitats within Apalachicola Bay,...

  13. Sediment grab data from October 1999 in Apalachicola Bay, Florida

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Apalachicola Bay National Estuarine Research Reserve and the NOAA Office for Coastal Management worked together to map benthic habitats within Apalachicola Bay,...

  14. South Bay Salt Pond Restoration, Phase II at Ravenswood

    Science.gov (United States)

    Information about the South Bay Salt Pond Restoration Project: Phase II Construction at Ravenswood, part of an EPA competitive grant program to improve SF Bay water quality focused on restoring impaired waters and enhancing aquatic resources.

  15. Phytoplankton and nutrients studies in Magu bay, Speke gulf, Lake ...

    African Journals Online (AJOL)

    chemical parameters were studied in Magu Bay, Lake Victoria, in May 2001. Investigations on the influence of Simiyu River on the biological and physical characteristics of the Bay were carried out. Surface and bottom currents flowed in the ...

  16. Biology and subsistence hunting of geese at Chagvan Bay

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Chagvan Bay and Nanvak Bay are known to be important staging and/or stopover areas for large numbers of Pacific Brant (Branta bernicola) and Emperor Geese (Chen...

  17. 1999 RoxAnn Data Points from Apalachicola Bay, Florida

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Apalachicola Bay National Estuarine Research Reserve and the NOAA Office for Coastal Management worked together to map benthic habitats within Apalachicola Bay,...

  18. Technical Support Documents Used to Develop the Chesapeake Bay TMDL

    Science.gov (United States)

    The Chesapeake Bay TMDL development was supported by several technical documents for water quality standards and allocation methodologies specific to the Chesapeake Bay. This page provides the technical support documents.

  19. Spatial variability in organic material sinking export in the Hudson Bay system, Canada, during fall

    Science.gov (United States)

    Lapoussière, Amandine; Michel, Christine; Gosselin, Michel; Poulin, Michel

    2009-05-01

    Spatial variations in the sinking export of organic material were assessed within the Hudson Bay system (i.e., Hudson Bay, Hudson Strait and Foxe Basin) during the second oceanographic expedition of ArcticNet, on board the CCGS Amundsen in early fall 2005. Sinking fluxes of particulate organic material were measured using short-term free-drifting particle interceptor traps deployed at 50, 100 and 150 m for 8-20 h at eight stations. Measurements of chlorophyll a (chl a), pheopigments (pheo), particulate organic carbon (POC), biogenic silica (BioSi), protists, fecal pellets and bacteria were performed on the collected material. In parallel, sea surface salinity and temperature were determined at 121 stations in the Hudson Bay system. Three hydrographic regions presenting different sedimentation patterns were identified based on average surface salinity and temperature. Hudson Strait was characterized by a marine signature, with high salinity (average=32.3) and low temperature (average=2.1 °C). Eastern Hudson Bay was strongly influenced by river runoff and showed the lowest average salinity (26.6) and highest average temperature (7.6 °C) of the three regions. Western Hudson Bay showed intermediate salinity (average=29.4) and temperature (average=4.4 °C). Sinking fluxes of total pigments (chl a+pheo: 3.37 mg m -2 d -1), diatom-associated carbon (19.8 mg m -2 d -1) and BioSi (50.2 mg m -2 d -1) at 50 m were highest in Hudson Strait. Eastern Hudson Bay showed higher sinking fluxes of total pigments (0.52 mg m -2 d -1), diatom-associated carbon (3.29 mg m -2 d -1) and BioSi (36.6 mg m -2 d -1) compared to western Hudson Bay (0.19, 0.05 and 7.76 mg m -2 d -1, respectively). POC sinking fluxes at 50 m were low and relatively uniform throughout the Hudson Bay system (50.0-76.8 mg C m -2 d -1), but spatial variations in the composition of the sinking organic material were observed. A large part (37-78%) of the total sinking POC was unidentifiable by microscopic observation

  20. Lagrangian transport in a microtidal coastal area: the Bay of Palma, island of Mallorca, Spain

    Science.gov (United States)

    Hernández-Carrasco, I.; López, C.; Orfila, A.; Hernández-García, E.

    2013-10-01

    Coastal transport in the Bay of Palma, a small region in the island of Mallorca, Spain, is characterized in terms of Lagrangian descriptors. The data sets used for this study are the output for two months (one in autumn and one in summer) of a high resolution numerical model, ROMS (Regional Ocean Model System), forced atmospherically and with a spatial resolution of 300 m. The two months were selected because of their different wind regime, which is the main driver of the sea dynamics in this area. Finite-size Lyapunov exponents (FSLEs) were used to locate semi-persistent Lagrangian coherent structures (LCS) and to understand the different flow regimes in the bay. The different wind directions and regularity in the two months have a clear impact on the surface bay dynamics, whereas only topographic features appear clearly in the bottom structures. The fluid interchange between the bay and the open ocean was studied by computing particle trajectories and residence time (RT) maps. The escape rate of particles out of the bay is qualitatively different, with a 32% greater escape rate of particles to the ocean in October than in July, owing to the different geometric characteristics of the flow. We show that LCSs separate regions with different transport properties by displaying spatial distributions of residence times on synoptic Lagrangian maps together with the location of the LCSs. Correlations between the time-dependent behavior of FSLE and RT are also investigated, showing a negative dependence when the stirring characterized by FSLE values moves particles in the direction of escape.

  1. 77 FR 14276 - Regulated Navigation Area; Little Bay Bridge Construction, Little Bay, Portsmouth, NH

    Science.gov (United States)

    2012-03-09

    ...The Coast Guard is establishing a regulated navigation area (RNA) on the navigable waters of Little Bay in the Piscataqua River under and surrounding the Little Bay and General Sullivan Bridges in order to facilitate construction of the Little Bay Bridge between Newington, NH and Dover, NH. This temporary interim rule is necessary to provide for the safety of life on the navigable waters during bridge construction operations that could pose an imminent hazard to vessels operating in the area. This rule implements certain safety measures, including speed restrictions and the temporary suspension of vessel traffic during construction operations.

  2. Integrating Fluvial and Oceanic Drivers in Operational Flooding Forecasts for San Francisco Bay

    Science.gov (United States)

    Herdman, Liv; Erikson, Li; Barnard, Patrick; Kim, Jungho; Cifelli, Rob; Johnson, Lynn

    2016-04-01

    The nine counties that make up the San Francisco Bay area are home to 7.5 million people and these communties are susceptible to flooding along the bay shoreline and inland creeks that drain to the bay. A forecast model that integrates fluvial and oceanic drivers is necessary for predicting flooding in this complex urban environment. The U.S. Geological Survey ( USGS) and National Weather Service (NWS) are developing a state-of-the-art flooding forecast model for the San Francisco Bay area that will predict watershed and ocean-based flooding up to 72 hours in advance of an approaching storm. The model framework for flood forecasts is based on the USGS-developed Coastal Storm Modeling System (CoSMoS) that was applied to San Francisco Bay under the Our Coast Our Future project. For this application, we utilize Delft3D-FM, a hydrodynamic model based on a flexible mesh grid, to calculate water levels that account for tidal forcing, seasonal water level anomalies, surge and in-Bay generated wind waves from the wind and pressure fields of a NWS forecast model, and tributary discharges from the Research Distributed Hydrologic Model (RDHM), developed by the NWS Office of Hydrologic Development. The flooding extent is determined by overlaying the resulting water levels onto a recently completed 2-m digital elevation model of the study area which best resolves the extensive levee and tidal marsh systems in the region. Here we present initial pilot results of hindcast winter storms in January 2010 and December 2012, where the flooding is driven by oceanic and fluvial factors respectively. We also demonstrate the feasibility of predicting flooding on an operational time scale that incorporates both atmospheric and hydrologic forcings.

  3. Holocene evolution of Apalachicola Bay, Florida

    Science.gov (United States)

    Osterman, Lisa E.; Twichell, David C.

    2011-01-01

    A program of geophysical mapping and vibracoring was conducted in 2007 to better understand the geologic evolution of Apalachicola Bay and its response to sea-level rise. A detailed geologic history could help better understand how this bay may respond to both short-term (for example, storm surge) and long-term sea-level rise. The results of this study were published (Osterman and others, 2009) as part of a special issue of Geo-Marine Letters that documents early results from the Northern Gulf of Mexico (NGOM) Ecosystem Change and Hazard Susceptibility Project.

  4. An Empirical Bayes Approach to Spatial Analysis

    Science.gov (United States)

    Morris, C. N.; Kostal, H.

    1983-01-01

    Multi-channel LANDSAT data are collected in several passes over agricultural areas during the growing season. How empirical Bayes modeling can be used to develop crop identification and discrimination techniques that account for spatial correlation in such data is considered. The approach models the unobservable parameters and the data separately, hoping to take advantage of the fact that the bulk of spatial correlation lies in the parameter process. The problem is then framed in terms of estimating posterior probabilities of crop types for each spatial area. Some empirical Bayes spatial estimation methods are used to estimate the logits of these probabilities.

  5. Paleoproterozoic Collisional Structures in the Hudson Bay Lithosphere Constrained by Multi-Observable Probabilistic Inversion

    Science.gov (United States)

    Darbyshire, F. A.; Afonso, J. C.; Porritt, R. W.

    2015-12-01

    The Paleozoic Hudson Bay intracratonic basin conceals a Paleoproterozoic Himalayan-scale continental collision, the Trans-Hudson Orogen (THO), which marks an important milestone in the assembly of the Canadian Shield. The geometry of the THO is complex due to the double-indentor geometry of the collision between the Archean Superior and Western Churchill cratons. Seismic observations at regional scale show a thick, seismically fast lithospheric keel beneath the entire region; an intriguing feature of recent models is a 'curtain' of slightly lower wavespeeds trending NE-SW beneath the Bay, which may represent the remnants of more juvenile material trapped between the two Archean continental cores. The seismic models alone, however, cannot constrain the nature of this anomaly. We investigate the thermal and compositional structure of the Hudson Bay lithosphere using a multi-observable probabilistic inversion technique. This joint inversion uses Rayleigh wave phase velocity data from teleseismic earthquakes and ambient noise, geoid anomalies, surface elevation and heat flow to construct a pseudo-3D model of the crust and upper mantle. Initially a wide range of possible mantle compositions is permitted, and tests are carried out to ascertain whether the lithosphere is stratified with depth. Across the entire Hudson Bay region, low temperatures and a high degree of chemical depletion characterise the mantle lithosphere. Temperature anomalies within the lithosphere are modest, as may be expected from a tectonically-stable region. The base of the thermal lithosphere lies at depths of >250 km, reaching to ~300 km depth in the centre of the Bay. Lithospheric stratification, with a more-depleted upper layer, is best able to explain the geophysical data sets and surface observables. Some regions, where intermediate-period phase velocities are high, require stronger mid-lithospheric depletion. In addition, a narrow region of less-depleted material extends NE-SW across the Bay

  6. Chondrichthyan occurrence and abundance trends in False Bay ...

    African Journals Online (AJOL)

    Commercial fishing in False Bay, South Africa, began in the 1600s. Today chondrichthyans are regularly taken in fisheries throughout the bay. Using a combination of catch, survey and life history data, the occurrence and long-term changes in populations of chondrichthyans in False Bay are described. Analyses of time ...

  7. 33 CFR 117.323 - Outer Clam Bay

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Outer Clam Bay 117.323 Section... DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Florida § 117.323 Outer Clam Bay The drawspan of the Outer Clam Bay Boardwalk Drawbridge shall open on signal if at least 30 minutes advance notice is given. ...

  8. 33 CFR 162.150 - Maumee Bay and River, Ohio.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Maumee Bay and River, Ohio. 162... (CONTINUED) PORTS AND WATERWAYS SAFETY INLAND WATERWAYS NAVIGATION REGULATIONS § 162.150 Maumee Bay and River, Ohio. (a) In Maumee Bay (lakeward of Maumee River Lighted Buoy 49(L/L No. 770)), no vessel greater than...

  9. Naïve Bayes classification in R

    OpenAIRE

    Zhang, Zhongheng

    2016-01-01

    Naïve Bayes classification is a kind of simple probabilistic classification methods based on Bayes’ theorem with the assumption of independence between features. The model is trained on training dataset to make predictions by predict() function. This article introduces two functions naiveBayes() and train() for the performance of Naïve Bayes classification.

  10. Naive Bayes and Text Classification I - Introduction and Theory

    OpenAIRE

    Raschka, Sebastian

    2014-01-01

    Naive Bayes classifiers, a family of classifiers that are based on the popular Bayes' probability theorem, are known for creating simple yet well performing models, especially in the fields of document classification and disease prediction. In this article, we will look at the main concepts of naive Bayes classification in the context of document categorization.

  11. Sequential hypothesis testing with Bayes factors: Efficiently testing mean differences.

    Science.gov (United States)

    Schönbrodt, Felix D; Wagenmakers, Eric-Jan; Zehetleitner, Michael; Perugini, Marco

    2017-06-01

    Unplanned optional stopping rules have been criticized for inflating Type I error rates under the null hypothesis significance testing (NHST) paradigm. Despite these criticisms, this research practice is not uncommon, probably because it appeals to researcher's intuition to collect more data to push an indecisive result into a decisive region. In this contribution, we investigate the properties of a procedure for Bayesian hypothesis testing that allows optional stopping with unlimited multiple testing, even after each participant. In this procedure, which we call Sequential Bayes Factors (SBFs), Bayes factors are computed until an a priori defined level of evidence is reached. This allows flexible sampling plans and is not dependent upon correct effect size guesses in an a priori power analysis. We investigated the long-term rate of misleading evidence, the average expected sample sizes, and the biasedness of effect size estimates when an SBF design is applied to a test of mean differences between 2 groups. Compared with optimal NHST, the SBF design typically needs 50% to 70% smaller samples to reach a conclusion about the presence of an effect, while having the same or lower long-term rate of wrong inference. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  12. On Measurements of the Tide at Churchill, Hudson Bay

    Science.gov (United States)

    Ray, Richard D.

    2016-01-01

    Since the late 1990s the semi-diurnal tide at Churchill, on the western shore of Hudson Bay, has been decreasing in amplitude, with M(sub 2) amplitudes falling from approximately 154 cm in 1998 to 146 cm in 2012 and 142 cm in 2014. There has been a corresponding small increase in phase lag. Mean low water, decreasing throughout most of the twentieth century, has levelled off. Although the tidal changes could reflect merely a malfunctioning tide gauge, the fact that there are no other measurements in the region and the possibility that the tide is revealing important environmental changes calls for serious investigation. Satellite altimeter measurements of the tide in Hudson Bay are complicated by the seasonal ice cover; at most locations less than 40% of satellite passes return valid ocean heights and even those can be impacted by errors from sea ice. Because the combined TOPEX/Poseidon, Jason-1, and Jason-2 time series is more than 23 years long, it is now possible to obtain sufficient data at crossover locations near Churchill to search for tidal changes. The satellites sense no changes in M(sub 2) that are comparable to the changes seen at the Churchill gauge. The changes appear to be localized to the harbour, or to the Churchill River, or to the gauge itself.

  13. 33 CFR 100.124 - Maggie Fischer Memorial Great South Bay Cross Bay Swim, Great South Bay, New York.

    Science.gov (United States)

    2010-07-01

    .... (a) Regulated area. All navigable waters of Great South Bay, NY within a 100 yard radius of each... the Fire Island Lighthouse Dock in approximate position 40°38′01″ N 073°13′07″ W, northerly through.... (1) No person or vessel may enter, transit, or remain within 100 yards of any swimmer or safety craft...

  14. Susceptibilities of Human Cytomegalovirus Clinical Isolates to BAY38-4766, BAY43-9695, and Ganciclovir

    Science.gov (United States)

    McSharry, James J.; McDonough, Ann; Olson, Betty; Hallenberger, Sabine; Reefschlaeger, Juergen; Bender, Wolfgang; Drusano, George L.

    2001-01-01

    BAY38-4766 and BAY43-9695 are nonnucleosidic compounds with activities against human cytomegalovirus (HCMV). Two phenotypic assays were used to determine the drug susceptibilities of 36 HCMV clinical isolates to the BAY compounds and ganciclovir. Using either assay, both BAY compounds at a concentration of approximately 1 μM inhibited the replication of all 36 HCMV clinical isolates, including 11 ganciclovir-resistant clinical isolates, by 50%. PMID:11557492

  15. Surface Currents and Winds at the Delaware Bay Mouth

    Energy Technology Data Exchange (ETDEWEB)

    Muscarella, P A; Barton, N P; Lipphardt, B L; Veron, D E; Wong, K C; Kirwan, A D

    2011-04-06

    Knowledge of the circulation of estuaries and adjacent shelf waters has relied on hydrographic measurements, moorings, and local wind observations usually removed from the region of interest. Although these observations are certainly sufficient to identify major characteristics, they lack both spatial resolution and temporal coverage. High resolution synoptic observations are required to identify important coastal processes at smaller scales. Long observation periods are needed to properly sample low-frequency processes that may also be important. The introduction of high-frequency (HF) radar measurements and regional wind models for coastal studies is changing this situation. Here we analyze synoptic, high-resolution surface winds and currents in the Delaware Bay mouth over an eight-month period (October 2007 through May 2008). The surface currents were measured by two high-frequency radars while the surface winds were extracted from a data-assimilating regional wind model. To illustrate the utility of these monitoring tools we focus on two 45-day periods which previously were shown to present contrasting pictures of the circulation. One, the low-outflow period is from 1 October through 14 November 2007; the other is the high-outflow period from 3 March through 16 April 2008. The large-scale characteristics noted by previous workers are clearly corroborated. Specifically the M2 tide dominates the surface currents, and the Delaware Bay outflow plume is clearly evident in the low frequency currents. Several new aspects of the surface circulation were also identified. These include a map of the spatial variability of the M2 tide (validating an earlier model study), persistent low-frequency cross-mouth flow, and a rapid response of the surface currents to a changing wind field. However, strong wind episodes did not persist long enough to set up a sustained Ekman response.

  16. Seasonal Variation of Colored Dissolved Organic Matter in Barataria Bay, Louisiana, Using Combined Landsat and Field Data

    Directory of Open Access Journals (Sweden)

    Ishan Joshi

    2015-09-01

    Full Text Available Coastal bays, such as Barataria Bay, are important transition zones between the terrigenous and marine environments that are also optically complex due to elevated amounts of particulate and dissolved constituents. Monthly field data collected over a period of 15 months in 2010 and 2011 in Barataria Bay were used to develop an empirical band ratio algorithm for the Landsat-5 TM that showed a good correlation with the Colored Dissolved Organic Matter (CDOM absorption coefficient at 355 nm (ag355 (R2 = 0.74. Landsat-derived CDOM maps generally captured the major details of CDOM distribution and seasonal influences, suggesting the potential use of Landsat imagery to monitor biogeochemistry in coastal water environments. An investigation of the seasonal variation in ag355 conducted using Landsat-derived ag355 as well as field data suggested the strong influence of seasonality in the different regions of the bay with the marine end members (lower bay experiencing generally low but highly variable ag355 and the freshwater end members (upper bay experiencing high ag355 with low variability. Barataria Bay experienced a significant increase in ag355 during the freshwater release at the Davis Pond Freshwater Diversion (DPFD following the Deep Water Horizon oil spill in 2010 and following the Mississippi River (MR flood conditions in 2011, resulting in a weak linkage to salinity in comparison to the other seasons. Tree based statistical analysis showed the influence of high river flow conditions, high- and low-pressure systems that appeared to control ag355 by ~28%, 29% and 43% of the time duration over the study period at the marine end member just outside the bay. An analysis of CDOM variability in 2010 revealed the strong influence of the MR in controlling CDOM abundance in the lower bay during the high flow conditions, while strong winds associated with cold fronts significantly increase CDOM abundance in the upper bay, thus revealing the important

  17. Geology and geomorphology--Drakes Bay and Vicinity Bay Map Area, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the geologic and geomorphic map of the Drakes Bay and Vicinity map area, California. The polygon shapefile is included in...

  18. Pärnu Bay Golf Club = Pärnu Bay Golf Club / Arhitekt11

    Index Scriptorium Estoniae

    2016-01-01

    Pärnu Bay Golf Club, arhitektid Jürgen Lepper, Anto Savi, Margus Soonets, Janar Toomesso (Arhitekt11), sisearhitektid Liina Vaino, Kaari Metslang, Hannelore Kääramees (Arhitekt11). Kultuurkapitali Arhitektuuri sihtkapitali aastapreemia nominent 2016

  19. Gravity cores from San Pablo Bay and Carquinez Strait, San Francisco Bay, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data release contains information on gravity cores that were collected by the U.S. Geological Survey in the area of San Pablo Bay and Carquinez Strait,...

  20. Contaminants in redhead ducks wintering in Baffin Bay and Redfish Bay, Texas

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A sample of 39 redhead ducks was collected from Redfish and Baffin Bays on the Texas Coast during the winter of 1988-1989 to obtain baseline information on...

  1. Florida Bay Science Program: a Synthesis of Research on Florida Bay

    OpenAIRE

    Hunt, John; Nuttle, William

    2007-01-01

    This report documents the progress made toward the objectives established in the Strategic Plan revised in 1997 for the agencies cooperating in the program. These objectives are expressed as five questions that organized the research on the Florida Bay ecosystem: Ecosystem History What was the Florida Bay ecosystem like 50, 100, and 150 years ago? Question 1—Physical Processes How and at what rates do storms, changing freshwater flows, sea level rise, and local evaporatio...

  2. Talus Lex: Regulatory Approaches to Reducing Mercury Concentrations in San Francisco Bay Fish.

    Science.gov (United States)

    Abu-Saba, D. E.; Flegal, D. R.; Ganguli, P. M.; Whyte, D. C.; Mumley, D. E.; Mason, D. P.

    2001-12-01

    7 mg/L or more in that region. But many of the processes that influence mercury bioaccumulation, such as microbial assemblage, sulfate concentration, and organic carbon loading, are complex, interacting factors that cannot be expressed as simple numeric limits. The Water Quality Control Plan for San Francisco Bay has a narrative objective for bioaccumulation that states that "controllable water quality factors shall not cause a detrimental increase in the concentrations of toxic substances found in bottom sediments or aquatic life." To effectively implement that objective, we need basic science research to develop sound guidance for the creation, restoration, and management of wetlands and marshes surrounding the Bay.

  3. Drivers of phytoplankton dynamics in old Tampa Bay, FL (USA), a subestuary lagging in ecosystem recovery

    Science.gov (United States)

    Corcoran, Alina A.; Wolny, Jennifer; Leone, Erin; Ivey, James; Murasko, Susan

    2017-02-01

    northernmost sampling station being the most unique in the region. This work contributes to the knowledge of phytoplankton biomass and community composition in Tampa Bay by generating spatially and temporally rich phytoplankton community and environmental data for the Old Tampa Bay subestuary. Moreover, it enhances our understanding of bloom drivers and provides recommendations for ecosystem management. Specifically, our findings support continued nutrient reduction measures as a way to mitigate seasonal blooms of diatoms, cyanobacteria and chlorophytes, but not necessarily blooms of P. bahamense. Prediction and mitigation of P. bahamnese blooms should incorporate first order drivers such as cyst location and abundance.

  4. Teaching Sustainability and Resource Management Using NOAA's Voices Of The Bay Community Fisheries Education Curriculum

    Science.gov (United States)

    Hams, J. E.; Uttal, L.; Hunter-Thomson, K.; Nachbar, S.

    2010-12-01

    This presentation highlights the implementation of the NOAA VOICES OF THE BAY education curriculum at a two-year college. The VOICES OF THE BAY curriculum provides students with an understanding of the marine ecology, economy, and culture of fisheries through three interdisciplinary modules that use hands-on activities while meeting a wide range of science, math, social science, and communications standards. In the BALANCE IN THE BAY module, students use critical-thinking skills and apply principles of ecosystem-based management to analyze data, debate and discuss their findings, and make decisions that recognize the complex dynamics associated with maintaining a balance in fisheries. Through role-playing, teamwork, and a little fate, the FROM OCEAN TO TABLE module provides students with an opportunity to get an insider’s view of what it takes to be an active stakeholder in a commercial fishery. In the CAPTURING THE VOICES OF THE BAY module, students research, plan, and conduct personal interviews with citizens of the local fishing community and explore the multiple dimensions of fisheries and how they inter-connect through the lives of those who live and work in the region. The VOICES OF THE BAY modules were introduced into the curriculum at Los Angeles Valley College during the Fall 2009 semester and are currently being used in the introductory Oceanography lecture, introductory Oceanography laboratory, and Environmental Science laboratory courses. Examples of curriculum materials being used (power point presentations, module worksheets and simulated fishing activities) will be presented. In addition, samples of completed student worksheets for the three interdisciplinary modules are provided. Students commented that their overall awareness and knowledge of the issues involved in sustainable fishing and managing fishery resources increased following completion of the VOICES OF THE BAY education curriculum. Students enrolled in the laboratory sections commented

  5. Carolina bays of the Savannah River Plant

    Energy Technology Data Exchange (ETDEWEB)

    Schalles, J.F. (Creighton Univ., Omaha, NE (USA)); Sharitz, R.R.; Gibbons, J.W.; Leversee, G.J.; Knox, J.N. (Savannah River Ecology Lab., Aiken, SC (USA))

    1989-01-01

    Much of the research to date on the Carolina bays of the Savannah River Plant and elsewhere has focused on certain species or on environmental features. Different levels of detail exist for different groups of organisms and reflect the diverse interests of previous investigators. This report summarizes aspects of research to date and presents data from numerous studies. 70 refs., 14 figs., 12 tabs.

  6. Bathymetry (2011) for Coral Bay, St. John

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a LiDAR (Light Detection & Ranging) 0.3x0.3 meter resolution depth surface for Coral Bay, St. John in the U.S. Virgin Islands (USVI). The...

  7. Madreporaria from the Bay of Batavia

    NARCIS (Netherlands)

    Umbgrove, J.H.F.

    1939-01-01

    INTRODUCTION In the Bay of Batavia there are patch-reefs and cays in different stadia of development. Some are small reefs still rather deep below sea level, other reefs bear a small sand cay. On the larger coral sand islands vegetation has developed ; moreover shingle ramparts and a moat have come

  8. Bathymetry (2011) for Fish Bay, St. John

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a LiDAR (Light Detection & Ranging) 0.3x0.3 meter resolution depth surface for Fish Bay, St. John in the U.S. Virgin Islands (USVI). The...

  9. PEMANFATAN TEOREMA BAYES DALAM PENENTUAN PENYAKIT THT

    Directory of Open Access Journals (Sweden)

    Sri Winiarti

    2012-05-01

    Full Text Available Dalam konsep pelacakan dalam mencari solusi dengan pendekatan artificial inteligent, ada berbagai metode  yang dapat diterapkan untuk mengatasi masalah ketidakpastian saat proses pelacakan terjadi. Salah satunya adalah teorema bayes. Adanya ketidakpastian pada proses pelacakan dapat terjadi karena adanya perubahan pengetahuan yang ada di dalam sistem. Untuk itu diperlukan adanya suatu metode untuk mengatasi permasalahan tersebut. Dalam penelitian ini telah diterapkan suatu metode untuk mengatasi ketidakpastian dengan teorema Bayes pada kasus pelacakan untuk mendiagnosa penyakit pada THT (Telinga,Hidung dan Tenggorokan.  Subjek pada penelitian ini adalah proses pelacakan untuk menentukan penyakit THT dengan model penalaran forward chaining dan metode kepastiannya menggunakan teorema bayes dengan cara menghitung nilai probabilitas suatu penyakit dan membandingkan probabilitas setiap gejalanya. Model pengembangan perangkat lunak yang digunakan dalam penelitian ini adalah Waterfall. Metode Waterfall diawali dengan analisis data, perancangan sistem, pengkodean menggunakan Visual Basic 6.0, pengujian sistem dengan black box test dan alfa test. Dari penelitian yang dilakukan menghasilkan sebuah perangkat lunak yaitu  yang mampu menentukan penyakit pada THT dengan menerapkan metode bayes untuk mengatasi ketidakpastian. Hasil uji coba sistem menujukkan bahwa aplikasi ini layak dan dapat digunakan.

  10. Morphological features in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Sarma, K.V.L.N.S.; Ramana, M.V.; Subrahmanyam, V.; Krishna, K.S.; Ramprasad, T.; Desa, M.

    the NW-SE trending long profiles spaced at 30 nautical miles aided to improve the bathymetry chart of the Bay of Bengal. The echograms show some important geo-morphological features of the seafloor. One such feature is the "Swatch of no ground" which...

  11. Saginaw Bay, MI LiDAR

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TASK NAME:(NRCS) Saginaw Bay, MI LiDAR LiDAR Data Acquisition and Processing Production Task USGS Contract No. G10PC00057 Task Order No. G11PD01254 Woolpert Order...

  12. (IMPS) at Makoba Bay, Zanzibar, Tanzania

    African Journals Online (AJOL)

    Daisy Ouya

    sedimentation pond, in that order. Water from the reservoir flows through the pond system by gravity. In the late 18th Century a powerful cyclone hit. Unguja Island. As a result, the estuarine sediments in the Bay have remained blackish in colour, sticky,.

  13. Summary report on Bristol Bay murre mortality

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — At least 86,000 common murres died in Bristol Bay, Alaska during a brief period in late April of this year. Evidence suggests that it was a catastrophic event of...

  14. Comparison of Ecological Impacts of Postulated Oil Spills at Selected Alaskan Locations. Volume 1. Introduction, Summary, Methodology, Evaluation and Appendices

    Science.gov (United States)

    1975-06-01

    Graham Kami’s hak Bay Unimak Pass Port Möller 1 Kvichak Bay St. Matthew Island Nome Cape Blossom Offshore Prudhoe Onshore Prudhoe Umiat...Crossing, the cases found to have the greatest impact involved Port Graham, Valdez Narrows, Drift River, and Unimak Pass. The highest impact score...Valdez Narrows, Port Graham, Unimak Pass, Yukon River Crossing, and Drift River dominated the list of high impact scores in those cases where

  15. An empirical Bayes approach for the Poisson life distribution.

    Science.gov (United States)

    Canavos, G. C.

    1973-01-01

    A smooth empirical Bayes estimator is derived for the intensity parameter (hazard rate) in the Poisson distribution as used in life testing. The reliability function is also estimated either by using the empirical Bayes estimate of the parameter, or by obtaining the expectation of the reliability function. The behavior of the empirical Bayes procedure is studied through Monte Carlo simulation in which estimates of mean-squared errors of the empirical Bayes estimators are compared with those of conventional estimators such as minimum variance unbiased or maximum likelihood. Results indicate a significant reduction in mean-squared error of the empirical Bayes estimators over the conventional variety.

  16. Chesapeake Bay Watershed - Protecting the Chesapeake Bay and its rivers through science, restoration, and partnership

    Science.gov (United States)

    ,

    2012-01-01

    The Chesapeake Bay, the Nation's largest estuary, has been degraded due to the impact of human-population increase, which has doubled since 1950, resulting in degraded water quality, loss of habitat, and declines in populations of biological communities. Since the mid-1980s, the Chesapeake Bay Program (CBP), a multi-agency partnership which includes the Department of Interior (DOI), has worked to restore the Bay ecosystem. The U.S. Geological Survey (USGS) has the critical role of providing unbiased scientific information that is utilized to document and understand ecosystem change to help assess the effectiveness of restoration strategies in the Bay and its watershed. The USGS revised its Chesapeake Bay science plan for 2006-2011 to address the collective needs of the CBP, DOI, and USGS with a mission to provide integrated science for improved understanding and management of the Bay ecosystem. The USGS science themes for this mission are: Causes and consequences of land-use change; Impact of climate change and associated hazards; Factors affecting water quality and quantity; Ability of habitat to support fish and bird populations; and Synthesis and forecasting to improve ecosystem assessment, conservation, and restoration.

  17. Responses of upland herpetofauna to the restoration of Carolina Bays and thinning of forested Bay Margins.

    Energy Technology Data Exchange (ETDEWEB)

    Ledvina, Joseph A.

    2008-05-01

    Research on the effects of wetland restoration on reptiles and amphibians is becoming more common, but almost all of these studies have observed the colonization of recently disturbed habitats that were completely dry at the time of restoration. In a similar manner, investigations herpetofaunal responses to forest management have focused on clearcuts, and less intensive stand manipulations are not as well studied. To evaluate community and population responses of reptiles and amphibians to hydrology restoration and canopy removal in the interior of previously degraded Carolina bays, I monitored herpetofauna in the uplands adjacent to six historically degraded Carolina bays at the Savannah River Site (SRS) in South Carolina for four years after restoration. To evaluate the effects of forest thinning on upland herpetofauna, forests were thinned in the margins of three of these bays. I used repeated measures ANOVA to compare species richness and diversity and the abundance of selected species and guilds between these bays and with those at three reference bays that were not historically drained and three control bays that remained degraded. I also used Non-metric Multidimensional Scaling (NMDS) to look for community-level patterns based treatments.

  18. Residency, habitat use and sexual segregation of white sharks, Carcharodon carcharias in False Bay, South Africa.

    Science.gov (United States)

    Kock, Alison; O'Riain, M Justin; Mauff, Katya; Meÿer, Michael; Kotze, Deon; Griffiths, Charles

    2013-01-01

    White sharks (Carcharodon carcharias) are threatened apex predators and identification of their critical habitats and how these are used are essential to ensuring improved local and ultimately global white shark protection. In this study we investigated habitat use by white sharks in False Bay, South Africa, using acoustic telemetry. 56 sharks (39 female, 17 male), ranging in size from 1.7-5 m TL, were tagged with acoustic transmitters and monitored on an array of 30 receivers for 975 days. To investigate the effects of season, sex and size on habitat use we used a generalized linear mixed effects model. Tagged sharks were detected in the Bay in all months and across all years, but their use of the Bay varied significantly with the season and the sex of the shark. In autumn and winter males and females aggregated around the Cape fur seal colony at Seal Island, where they fed predominantly on young of the year seals. In spring and summer there was marked sexual segregation, with females frequenting the Inshore areas and males seldom being detected. The shift from the Island in autumn and winter to the Inshore region in spring and summer by females mirrors the seasonal peak in abundance of juvenile seals and of migratory teleost and elasmobranch species respectively. This study provides the first evidence of sexual segregation at a fine spatial scale and demonstrates that sexual segregation in white sharks is not restricted to adults, but is apparent for juveniles and sub-adults too. Overall, the results confirm False Bay as a critical area for white shark conservation as both sexes, across a range of sizes, frequent the Bay on an annual basis. The finding that female sharks aggregate in the Inshore regions when recreational use peaks highlights the need for ongoing shark-human conflict mitigation strategies.

  19. Selenium bioaccumulation and body condition in shorebirds and terns breeding in San Francisco Bay, California, USA

    Science.gov (United States)

    Ackerman, Joshua T.; Eagles-Smith, Collin A.

    2009-01-01

    The present study evaluated Se bioaccumulation in four waterbird species (n = 206 birds) that breed within San Francisco Bay, California, USA: American avocets (Recurvirostra americana), black-necked stilts (Himantopus mexicanus), Forster's terns (Sterna forsteri), and Caspian terns (Hydroprogne caspia). Selenium concentrations were variable and influenced by several factors, including species, region, reproductive stage, age, and sex. Adult Se concentrations (μg/g dry wt) in livers ranged from 3.07 to 48.70 in avocets (geometric mean ± standard error, 7.92 ± 0.64), 2.28 to 41.10 in stilts (5.29 ± 0.38), 3.73 to 14.50 in Forster's terns (7.13 ± 0.38), and 4.77 to 14.40 in Caspian terns (6.73 ± 0.78). Avocets had higher Se concentrations in the North Bay compared to the South Bay, whereas stilt Se concentrations were similar between these regions and Forster's terns had lower Se concentrations in the North Bay compared to the South Bay. Female avocets had higher Se concentrations than male avocets, but this was not the case for stilts and Forster's terns. Of the factors assessed, reproductive stage had the most consistent effect among species. Prebreeding birds tended to have higher liver Se concentrations than breeding birds, but this trend was statistically significant only for Forster's terns. Forster's tern chicks had lower Se concentrations than Forster's tern adults, whereas avocet and stilt adults and chicks were similar. Additionally, body condition was negatively related to liver Se concentrations in Forster's tern adults but not in avocet, stilt, or Caspian tern adults and chicks. These variable results illustrate the complexity of Se bioaccumulation and highlight the need to sample multiple species and examine several factors to assess the impact of Se on wildlife.

  20. POTENTIAL HAZARDS OF SEDIMENT IN KENDARI BAY, SOUTHEAST SULAWESI

    Directory of Open Access Journals (Sweden)

    Nur Adi Kristanto

    2017-07-01

    Full Text Available Kendari bay is located in front of Kendari city. There are two harbors in the inner part of bay which very important to support economic activities such as shipping and passenger transportation. The result of coastal characteristic mapping and physical oceanography survey show various coastal morphology, vegetation, weathering processes, sedimentation, currents, and water depth and sea floor morphology. Kendari bay is an enclosed bay; the area is wide in the inner part and narrow in mouth of bay (outlet, the morphology look like a bottle’s neck. Numerous mouth rivers are concentrate around the bay. The rivers load material from land since erosion on land is intensive enough. There is indication that sediment supplies from land trough river mouth not equivalent with outlet capacity. Sediment load is trapped in the inner bay caused the outlet morphology. So high sediment rate play an important role in the process of shallow of water depth in Kendari bay. This condition make the Kendari bay is a prone area of sediment hazard due to height rate of sedimentary process. Therefore, to anticipate the hazards, precaution should be taken related to the Kendari bay as the center of activities in southeast of Sulawesi. The further survey is needed such as marine geotechnique and on land environmental to collect data, which can be used as database for development planning. Key words: Potential hazard, sediment, Kendari Bay Teluk

  1. Biological baseline data Youngs Bay, Oregon, 1974

    Energy Technology Data Exchange (ETDEWEB)

    McMechan, K.J. (ed.); Higley, D.L.; Holton, R.L.

    1975-04-01

    This report presents biological baseline information gathered during the research project, Physical, Chemical and Biological Studies on Youngs Bay.'' Youngs Bay is a shallow embayment located on the south shore of the Columbia River, near Astoria, Oregon. Research on Youngs Bay was motivated by the proposed construction by Alumax Pacific Aluminum Corporation of an aluminum reduction plant at Warrenton, Oregon. The research was designed to provide biological baseline information on Youngs Bay in anticipation of potential harmful effects from plant effluents. The information collected concerns the kinds of animals found in the Youngs Bay area, and their distribution and seasonal patterns of abundance. In addition, information was collected on the feeding habits of selected fish species, and on the life history and behavioral characteristics of the most abundant benthic amphipod, Corophium salmonis. Sampling was conducted at approximately three-week intervals, using commonly accepted methods of animal collection. Relatively few stations were sampled for fish, because of the need to standardize conditions of capture. Data on fish capture are reported in terms of catch-per-unit effort by a particular sampling gear at a specific station. Methods used in sampling invertebrates were generally more quantitative, and allowed sampling at a greater variety of places, as well as a valid basis for the computation of densities. Checklists of invertebrate species and fish species were developed from these samples, and are referred to throughout the report. The invertebrate checklist is more specific taxonomically than are tables reporting invertebrate densities. This is because the methods employed in identification were more precise than those used in counts. 9 refs., 27 figs., 25 tabs.

  2. Metal Distribution in Sediments from the Ribeira Bay, Rio de Janeiro - Brazil

    Directory of Open Access Journals (Sweden)

    Cardoso André G. A.

    2001-01-01

    Full Text Available Investigation of metal distribution in preserved areas is highly relevant due to the present-day lack of reliable databases against which to assess contamination. 23 samples of surface sediments from the Ribeira Bay, Rio de Janeiro State, Brazil, were analyzed by ICP/AES for Ti, Ca, Mg, Fe, Al, Sr, La, V, Y, Ni, Cu, Cr, Mn and Zn. Hg concentrations were determined by CVAAS. With respect to Al, metals were classified as strongly correlated, correlated, inversely correlated and non-correlated. Cluster analysis of the concentration data confirmed this, except for Hg. Cluster analysis of the sampling sites produced three groups, on the basis of grainsize, continental input, and marine input. Climatic and hydrodynamic factors, as well as soil characteristics, are important controls of the metal distribution in this region. The Ribeira Bay has a natural background metal content, when compared with average shales and with other impacted and non-impacted regions.

  3. Search for a Light Sterile Neutrino at Daya Bay

    CERN Document Server

    An, F P; Band, H R; Beriguete, W; Bishai, M; Blyth, S; Butorov, I; Cao, G F; Cao, J; Chan, Y L; Chang, J F; Chang, L C; Chang, Y; Chasman, C; Chen, H; Chen, Q Y; Chen, S M; Chen, X; Chen, Y X; Chen, Y; Cheng, Y P; Cherwinka, J J; Chu, M C; Cummings, J P; de Arcos, J; Deng, Z Y; Ding, Y Y; Diwan, M V; Draeger, E; Du, X F; Dwyer, D A; Edwards, W R; Ely, S R; Fu, J Y; Ge, L Q; Gill, R; Gonchar, M; Gong, G H; Gong, H; Grassi, M; Gu, W Q; Guan, M Y; Guo, X H; Hackenburg, R W; Han, G H; Hans, S; He, M; Heeger, K M; Heng, Y K; Hinrichs, P; Hor, Y K; Hsiung, Y B; Hu, B Z; Hu, L M; Hu, L J; Hu, T; Hu, W; Huang, E C; Huang, H; Huang, X T; Huber, P; Hussain, G; Isvan, Z; Jaffe, D E; Jaffke, P; Jen, K L; Jetter, S; Ji, X P; Ji, X L; Jiang, H J; Jiao, J B; Johnson, R A; Kang, L; Kettell, S H; Kramer, M; Kwan, K K; Kwok, M W; Kwok, T; Lai, W C; Lau, K; Lebanowski, L; Lee, J; Lei, R T; Leitner, R; Leung, A; Leung, J K C; Lewis, C A; Li, D J; Li, F; Li, G S; Li, Q J; Li, W D; Li, X N; Li, X Q; Li, Y F; Li, Z B; Liang, H; Lin, C J; Lin, G L; Lin, P Y; Lin, S K; Lin, Y C; Ling, J J; Link, J M; Littenberg, L; Littlejohn, B R; Liu, D W; Liu, H; Liu, J L; Liu, J C; Liu, S S; Liu, Y B; Lu, C; Lu, H Q; Luk, K B; Ma, Q M; Ma, X Y; Ma, X B; Ma, Y Q; McDonald, K T; McFarlane, M C; McKeown, R D; Meng, Y; Mitchell, I; Kebwaro, J Monari; Nakajima, Y; Napolitano, J; Naumov, D; Naumova, E; Nemchenok, I; Ngai, H Y; Ning, Z; Ochoa-Ricoux, J P; Olshevski, A; Patton, S; Pec, V; Peng, J C; Piilonen, L E; Pinsky, L; Pun, C S J; Qi, F Z; Qi, M; Qian, X; Raper, N; Ren, B; Ren, J; Rosero, R; Roskovec, B; Ruan, X C; Shao, B B; Steiner, H; Sun, G X; Sun, J L; Tam, Y H; Tang, X; Themann, H; Tsang, K V; Tsang, R H M; Tull, C E; Tung, Y C; Viren, B; Vorobel, V; Wang, C H; Wang, L S; Wang, L Y; Wang, M; Wang, N Y; Wang, R G; Wang, W; Wang, W W; Wang, X; Wang, Y F; Wang, Z; Wang, Z M; Webber, D M; Wei, H Y; Wei, Y D; Wen, L J; Whisnant, K; White, C G; Whitehead, L; Wise, T; Wong, H L H; Wong, S C F; Worcester, E; Wu, Q; Xia, D M; Xia, J K; Xia, X; Xing, Z Z; Xu, J Y; Xu, J L; Xu, J; Xu, Y; Xue, T; Yan, J; Yang, C C; Yang, L; Yang, M S; Yang, M T; Ye, M; Yeh, M; Yeh, Y S; Young, B L; Yu, G Y; Yu, J Y; Yu, Z Y; Zang, S L; Zeng, B; Zhan, L; Zhang, C; Zhang, F H; Zhang, J W; Zhang, Q M; Zhang, Q; Zhang, S H; Zhang, Y C; Zhang, Y M; Zhang, Y H; Zhang, Y X; Zhang, Z J; Zhang, Z Y; Zhang, Z P; Zhao, J; Zhao, Q W; Zhao, Y; Zhao, Y B; Zheng, L; Zhong, W L; Zhou, L; Zhou, Z Y; Zhuang, H L; Zou, J H

    2014-01-01

    A search for light sterile neutrino mixing was performed with the first 217 days of data from the Daya Bay Reactor Antineutrino Experiment. The experiment's unique configuration of multiple baselines from six 2.9~GW$_{\\rm th}$ nuclear reactors to six antineutrino detectors deployed in two near (effective baselines 512~m and 561~m) and one far (1579~m) underground experimental halls makes it possible to test for oscillations to a fourth (sterile) neutrino in the $10^{\\rm -3}~{\\rm eV}^{2} < |\\Delta m_{41}^{2}| < 0.3~{\\rm eV}^{2}$ range. The relative spectral distortion due to electron antineutrino disappearance was found to be consistent with that of the three-flavor oscillation model. The derived limits on $\\sin^22\\theta_{14}$ cover the $10^{-3}~{\\rm eV}^{2} \\lesssim |\\Delta m^{2}_{41}| \\lesssim 0.1~{\\rm eV}^{2}$ region, which was largely unexplored.

  4. Biological and geochemical data along Indian Point, Vermilion Bay, Louisiana

    Science.gov (United States)

    Richwine, Kathryn A.; Marot, Marci E.; Smith, Christopher G.; Osterman, Lisa E.; Adams, C. Scott

    2015-09-14

    Scientists from the U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center collected shallow sediment cores and surface samples from a coastal salt marsh environment next to Vermilion Bay in southwest Louisiana in January 2013. The sampling was part of a larger USGS study to gather data for assessing environmental changes over the past 150 years. The objective of the study was to expand upon the historical context of sea level and storms affecting coastal systems and how these systems might change under persistent or varying conditions. The data from this report add to a regional environmental change database that aids with the continuing effort to understand the evolution of coastal systems.

  5. Search for a Light Sterile Neutrino at Daya Bay

    Science.gov (United States)

    Wong, H. L. H.; Daya Bay Collaboration

    2017-09-01

    The Daya Bay reactor neutrino experiment’s unique configuration of multiple baselines from six 2.9 GW th nuclear reactors to eight antineutrino detectors deployed in two near (effective baselines ∼500 m and ∼600 m) and one far (effective baseline ∼1600 m) underground experimental halls makes it possible to look for oscillations with a fourth (sterile) neutrino in the {10}-3{{{ eV}}}2≲ |Δ {m}412|≲ 0.3{{{ eV}}}2 range. The relative spectral distortion due to the disappearance of electron antineutrinos was found to be consistent with that of the three-flavor oscillation model. The resulting limits on sin22θ 14 constitute the world’s best for the |Δ {m}412|≲ 0.2{{{ eV}}}2 region.

  6. Effects of Climate Change on Range Forage Production in the San Francisco Bay Area

    Science.gov (United States)

    Chaplin-Kramer, Rebecca; George, Melvin R.

    2013-01-01

    The San Francisco Bay Area in California, USA is a highly heterogeneous region in climate, topography, and habitats, as well as in its political and economic interests. Successful conservation strategies must consider various current and future competing demands for the land, and should pay special attention to livestock grazing, the dominant non-urban land-use. The main objective of this study was to predict changes in rangeland forage production in response to changes in temperature and precipitation projected by downscaled output from global climate models. Daily temperature and precipitation data generated by four climate models were used as input variables for an existing rangeland forage production model (linear regression) for California’s annual rangelands and projected on 244 12 km x 12 km grid cells for eight Bay Area counties. Climate model projections suggest that forage production in Bay Area rangelands may be enhanced by future conditions in most years, at least in terms of peak standing crop. However, the timing of production is as important as its peak, and altered precipitation patterns could mean delayed germination, resulting in shorter growing seasons and longer periods of inadequate forage quality. An increase in the frequency of extremely dry years also increases the uncertainty of forage availability. These shifts in forage production will affect the economic viability and conservation strategies for rangelands in the San Francisco Bay Area. PMID:23472102

  7. Bayes Node Energy Polynomial Distribution to Improve Routing in Wireless Sensor Network.

    Science.gov (United States)

    Palanisamy, Thirumoorthy; Krishnasamy, Karthikeyan N

    2015-01-01

    Wireless Sensor Network monitor and control the physical world via large number of small, low-priced sensor nodes. Existing method on Wireless Sensor Network (WSN) presented sensed data communication through continuous data collection resulting in higher delay and energy consumption. To conquer the routing issue and reduce energy drain rate, Bayes Node Energy and Polynomial Distribution (BNEPD) technique is introduced with energy aware routing in the wireless sensor network. The Bayes Node Energy Distribution initially distributes the sensor nodes that detect an object of similar event (i.e., temperature, pressure, flow) into specific regions with the application of Bayes rule. The object detection of similar events is accomplished based on the bayes probabilities and is sent to the sink node resulting in minimizing the energy consumption. Next, the Polynomial Regression Function is applied to the target object of similar events considered for different sensors are combined. They are based on the minimum and maximum value of object events and are transferred to the sink node. Finally, the Poly Distribute algorithm effectively distributes the sensor nodes. The energy efficient routing path for each sensor nodes are created by data aggregation at the sink based on polynomial regression function which reduces the energy drain rate with minimum communication overhead. Experimental performance is evaluated using Dodgers Loop Sensor Data Set from UCI repository. Simulation results show that the proposed distribution algorithm significantly reduce the node energy drain rate and ensure fairness among different users reducing the communication overhead.

  8. The chemical, physical and structural properties of estuarine ice in Great Bay, New Hampshire

    Science.gov (United States)

    Meese, D.A.; Gow, A.J.; Mayewski, P.A.; Ficklin, W.; Loder, T.C.

    1987-01-01

    The purpose of this study was to provide general information on the chemical, physical and structural properties of estuarine ice and show how it compares with sea ice found at higher latitudes in order to determine whether the ice in Great Bay can be used as an analog in the study of arctic sea ice. Ice cores and water samples were collected during the 1983-1984 winter season at Adams Point in Great Bay, New Hampshire. Concentrations of chloride, nitrogen (as nitrate and nitrite), bromide, phosphate, sulfate and silicate were determined for samples chosen on the basis of identifiable stratigraphic layers (i.e. bubble size and shape, sediment layers, etc.). Similarities between ice formation in Great Bay and those in the arctic regions include the nature of the freezing process and the ice types produced. In addition, the distribution and concentration of chemical constituents were found to be similar to those observed in arctic sea ice. Factors affecting the chemistry of the ice in Great Bay include rainfall during the freezing season, the presence of sediment layers in the ice cores, the nature of incorporation of brine into the crystal structure of the ice and the drainage of brine. ?? 1987.

  9. Hydrography of and biogeochemical inputs to Liberty Bay, a small urban embayment in Puget Sound, Washington

    Science.gov (United States)

    Takesue, Renee K.

    2011-01-01

    This multi-chapter report describes scientific and logistic understanding gained from a 2 year proof-of-concept study in Liberty Bay, a small urban embayment in central Puget Sound, Washington. The introductory chapter describes the regional and local setting, the high-level study goals, the site-specific urban stressors, and the interdisciplinary study approach. Subsequent data chapters describe detailed studies of various components of the Liberty Bay ecosystem: the aquatic environment (Chapter 2), surface and groundwater quantity and quality (Chapter 3), sediment quality (Chapter 4), eelgrass habitat (Chapter 5), carbon and nitrogen sources (Chapter 6), and a statistical model relating herring spawn probability to shoreline attributes (Chapter 7). The final chapter synthesizes knowledge about individual components into a system-wide understanding of how urbanization may affect the Liberty Bay ecosystem. The Liberty Bay study was conducted as part of the U.S. Geological Survey's Coastal Habitats in Puget Sound project, an interdisciplinary collaboration to understand physical and biological processes that affect nearshore ecosystems.

  10. Quantifying groundwater’s role in delaying improvements to Chesapeake Bay water quality

    Science.gov (United States)

    Sanford, Ward E.; Pope, Jason P.

    2013-01-01

    A study has been undertaken to determine the time required for the effects of nitrogen-reducing best management practices (BMPs) implemented at the land surface to reach the Chesapeake Bay via groundwater transport to streams. To accomplish this, a nitrogen mass-balance regression (NMBR) model was developed and applied to seven watersheds on the Delmarva Peninsula. The model included the distribution of groundwater return times obtained from a regional groundwater-flow (GWF) model, the history of nitrogen application at the land surface over the last century, and parameters that account for denitrification. The model was (1) able to reproduce nitrate concentrations in streams and wells over time, including a recent decline in the rate at which concentrations have been increasing, and (2) used to forecast future nitrogen delivery from the Delmarva Peninsula to the Bay given different scenarios of nitrogen load reduction to the water table. The relatively deep porous aquifers of the Delmarva yield longer groundwater return times than those reported earlier for western parts of the Bay watershed. Accordingly, several decades will be required to see the full effects of current and future BMPs. The magnitude of this time lag is critical information for Chesapeake Bay watershed managers and stakeholders.

  11. Effects of climate change on range forage production in the San Francisco Bay Area.

    Directory of Open Access Journals (Sweden)

    Rebecca Chaplin-Kramer

    Full Text Available The San Francisco Bay Area in California, USA is a highly heterogeneous region in climate, topography, and habitats, as well as in its political and economic interests. Successful conservation strategies must consider various current and future competing demands for the land, and should pay special attention to livestock grazing, the dominant non-urban land-use. The main objective of this study was to predict changes in rangeland forage production in response to changes in temperature and precipitation projected by downscaled output from global climate models. Daily temperature and precipitation data generated by four climate models were used as input variables for an existing rangeland forage production model (linear regression for California's annual rangelands and projected on 244 12 km x 12 km grid cells for eight Bay Area counties. Climate model projections suggest that forage production in Bay Area rangelands may be enhanced by future conditions in most years, at least in terms of peak standing crop. However, the timing of production is as important as its peak, and altered precipitation patterns could mean delayed germination, resulting in shorter growing seasons and longer periods of inadequate forage quality. An increase in the frequency of extremely dry years also increases the uncertainty of forage availability. These shifts in forage production will affect the economic viability and conservation strategies for rangelands in the San Francisco Bay Area.

  12. Effects of climate change on range forage production in the San Francisco Bay Area.

    Science.gov (United States)

    Chaplin-Kramer, Rebecca; George, Melvin R

    2013-01-01

    The San Francisco Bay Area in California, USA is a highly heterogeneous region in climate, topography, and habitats, as well as in its political and economic interests. Successful conservation strategies must consider various current and future competing demands for the land, and should pay special attention to livestock grazing, the dominant non-urban land-use. The main objective of this study was to predict changes in rangeland forage production in response to changes in temperature and precipitation projected by downscaled output from global climate models. Daily temperature and precipitation data generated by four climate models were used as input variables for an existing rangeland forage production model (linear regression) for California's annual rangelands and projected on 244 12 km x 12 km grid cells for eight Bay Area counties. Climate model projections suggest that forage production in Bay Area rangelands may be enhanced by future conditions in most years, at least in terms of peak standing crop. However, the timing of production is as important as its peak, and altered precipitation patterns could mean delayed germination, resulting in shorter growing seasons and longer periods of inadequate forage quality. An increase in the frequency of extremely dry years also increases the uncertainty of forage availability. These shifts in forage production will affect the economic viability and conservation strategies for rangelands in the San Francisco Bay Area.

  13. Interactions between finfish aquaculture and lobster catches in a sheltered bay.

    Science.gov (United States)

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

    2014-11-15

    Interactions between open-net pen finfish aquaculture and lobster catches in a sheltered bay in Nova Scotia, Canada, were investigated using fishermen's participatory research in annual lobster trap surveys over seven years. Fishermen recorded lobster catches during the last two weeks of May from 2007 to 2013. Catches for each trap haul were recorded separately for ovigerous and market-sized lobsters. Catch trends within the bay were compared to regional trends. Results of correlation analyses indicated that ovigerous catch trends were strongly affected by the fish farm's feeding/fallow periods. There was no significant correlation between trends for bay and LFA lobster landings. Patterns of lobster catch per unit effort extending over considerable distance in Port Mouton Bay appear to be influenced by proximity to the fish farm regardless of year-to-year variation in water temperatures and weather conditions. Odours and habitat changes surrounding open-net pen finfish operations are potential factors affecting lobster displacement. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. [Spatiotemporal distribution of total nitrogen and total phosphorus in sediments of Xiangxi Bay, Three Gorges Reservoir].

    Science.gov (United States)

    Zhang, Min; Xu, Yao-Yang; Shao, Mei-Ling; Cai, Qing-Hua

    2009-11-01

    The spatiotemporal distribution of total nitrogen (TN) and total phosphorus (TP) in sediments of Xiangxi Bay, Three Gorges Reservoir was investigated from October 2004 to July 2006, with related affecting factors analyzed. The TN and TP concentrations in the sediments were higher in the middle stretch but lower in the two edges of the Bay. The maximum value of TN concentration (1.08 mg x g(-1)) appeared in the middle part of the Bay, and the minimum (0.89 mg x g(-1)) occurred at the adjacent areas to the river mouth; while the maximum value of TP concentration (1.07 mg x g(-1)) appeared in the middle, and the minimum (0.80 mg x g(-1)) was in the edges of the Bay. The TN concentration decreased in the sequence of autumn-winter-spring, but increased from spring to summer dramatically; while the seasonal variation of TP concentration was not very significant, with the maximum occurred in spring. Significant inter-annual variations were observed in the TN and TP concentrations. The spatial distributions of TN and TP concentrations were mainly affected by the sedimentation of suspended matter. In the regions where sedimentation rate was high, the TN and TP concentrations were also very high. The seasonal fluctuation of TN concentration was mainly affected by river discharge, while that of TP concentration was mainly affected by point source pollution.

  15. Deep drilling in the Chesapeake Bay impact structure - An overview

    Science.gov (United States)

    Gohn, G.S.; Koeberl, C.; Miller, K.G.; Reimold, W.U.

    2009-01-01

    The late Eocene Chesapeake Bay impact structure lies buried at moderate depths below Chesapeake Bay and surrounding landmasses in southeastern Virginia, USA. Numerous characteristics made this impact structure an inviting target for scientific drilling, including the location of the impact on the Eocene continental shelf, its threelayer target structure, its large size (??85 km diameter), its status as the source of the North American tektite strewn field, its temporal association with other late Eocene terrestrial impacts, its documented effects on the regional groundwater system, and its previously unstudied effects on the deep microbial biosphere. The Chesapeake Bay Impact Structure Deep Drilling Project was designed to drill a deep, continuously cored test hole into the central part of the structure. A project workshop, funding proposals, and the acceptance of those proposals occurred during 2003-2005. Initial drilling funds were provided by the International Continental Scientific Drilling Program (ICDP) and the U.S. Geological Survey (USGS). Supplementary funds were provided by the National Aeronautics and Space Administration (NASA) Science Mission Directorate, ICDP, and USGS. Field operations were conducted at Eyreville Farm, Northampton County, Virginia, by Drilling, Observation, and Sampling of the Earth's Continental Crust (DOSECC) and the project staff during September-December 2005, resulting in two continuously cored, deep holes. The USGS and Rutgers University cored a shallow hole to 140 m in April-May 2006 to complete the recovered section from land surface to 1766 m depth. The recovered section consists of 1322 m of crater materials and 444 m of overlying postimpact Eocene to Pleistocene sediments. The crater section consists of, from base to top: basement-derived blocks of crystalline rocks (215 m); a section of suevite, impact melt rock, lithic impact breccia, and cataclasites (154 m); a thin interval of quartz sand and lithic blocks (26 m); a

  16. Interannual evolution of (submesoscale dynamics in the Bay of Biscay

    Directory of Open Access Journals (Sweden)

    G. Charria

    2017-09-01

    Full Text Available In the north-east Atlantic Ocean, the Bay of Biscay is an intersection between a coastal constrained dynamics (wide continental shelf and shelf break regions and an eastern boundary circulation system. In this framework, the eddy kinetic energy is 1 order of magnitude lower than in western boundary systems. To explore this coastal complex system, a high-resolution (1 km, 100 vertical sigma layers model experiment including tidal dynamics over a period of 10 years (2001–2010 has been implemented. The ability of the numerical environment to reproduce main patterns over interannual scales is demonstrated. Based on this experiment, the features of the (submesoscale processes are described in the deep part of the region (i.e. abyssal plain and continental slope. A system with the development of mixed layer instabilities at the end of winter is highlighted. Beyond confirming an observed behaviour of seasonal (submesoscale activity in other regions, the simulated period allows exploring the interannual variability of these structures. A relationship between the winter maximum of mixed layer depth and the intensity of (submesoscale related activity (vertical velocity, relative vorticity is revealed and can be explained by large-scale atmospheric forcings (e.g. the cold winter in 2005. The first submesoscale-permitting exploration of this 3-D coastal system shows the importance of (submesoscale activity in this region with its evolution implying a potentially significant impact on vertical and horizontal mixing.

  17. Nitrogen and phosphorus intake by phytoplankton in the Xiamen Bay

    Science.gov (United States)

    Lin, Cai; Li, Hui; He, Qing; Xu, Kuncan; Wu, Shengsan; Zhang, Yuanbiao; Chen, Jinmin; Chen, Baohong; Lin, Libin; Lu, Meiluan; Chen, Weifen; Tang, Rongkun; Ji, Weidong

    2010-01-01

    This paper describes a time series experiment examining the nitrogen and phosphorus intake of natural phytoplankton communities by a microcosms approach. Seawater samples containing natural phytoplankton communities were collected from waters around Baozhu Islet in inner Xiamen Bay and around Qingyu Islet in the outer bay. The goal was to elucidate the relationship between phytoplankton population enhancement, the biological removal of nitrogen and phosphorus from the seawater, and the phytoplankton nitrogen and phosphorus intake ratio based on nitrogen and phosphorus removal from seawater by phytoplankton, to provide a basis for detecting prewarning conditions for red tide and the assessment of red tide events. Two key results were obtained: 1. During the experiment, the nitrogen and phosphorus seawater concentrations in samples from these two sites were negatively and closely correlated to the logarithm of the phytoplankton cell concentration and to the value of the apparent oxygen increment. The ratio of the intake coefficients was 3.5:1 for phosphorus and 1.1:1 for nitrogen for the phytoplankton between these samples from around Baozhu Islet and Qingyu Islet, respectively. This indicates that the intake capabilities of phytoplankton for nitrogen in the two waters are essentially identical. However, for phosphorus, the capability was much higher in the Baozhu Islet waters than the Qingyu Islet waters. In other words, the phytoplankton in Qingyu Islet waters produced more biomass while consuming the same amount of phosphorus as the other waters; 2. The phytoplankton nitrogen and phosphorus intake ratio from the Baozhu Islet and Qingyu Islet waters was 20:1 and 36:1, respectively. The latter waters had a significantly higher ratio than the former and both were higher than the Redfield Ratio. These results indicate that nitrogen and phosphorus intake ratios by phytoplankton can vary significantly from region to region.

  18. The monterey bay broadband ocean bottom seismic observatory

    Directory of Open Access Journals (Sweden)

    R. Uhrhammer

    2006-06-01

    Full Text Available We report on the installation of a long-term buried ocean-floor broadband seismic station (MOBB in Monterey Bay, California (USA, 40km off-shore, at a water depth of 1000 m. The station was installed in April 2002 using a ship and ROV, in a collaborative effort between the Monterey Bay Aquarium Research Institute (MBARI and the Berkeley Seismological Laboratory (BSL. The station is located on the western side of the San Gregorio Fault, a major fault in the San Andreas plate boundary fault system. In addition to a 3-component CMG-1T seismometer package, the station comprises a current meter and Differential Pressure Gauge, both sampled at high-enough frequency (1 Hz to allow the study of relations between background noise on the seismometers and ocean waves and currents. The proximity of several land-based broadband seismic stations of the Berkeley Digital Seismic Network allows insightful comparisons of land/ocean background seismic noise at periods relevant to regional and teleseismic studies. The station is currently autonomous. Recording and battery packages are exchanged every 3 months during scheduled one day dives. Ultimately, this station will be linked to shore using continuous telemetry (cable and/or buoy and will contribute to the earthquake notification system in Northern California. We present examples of earthquake and noise data recorded during the first 6 months of operation of MOBB. Lessons learned from these and continued recordings will help understand the nature and character of background noise in regional off-shore environments and provide a reference for the installation of future off-shore temporary and permanent broadband seismic stations.

  19. Richness and Diversity of Bacterioplankton Species along an Estuarine Gradient in Moreton Bay, Australia

    OpenAIRE

    Hewson, Ian; Fuhrman, Jed A.

    2004-01-01

    Bacterioplankton community diversity was investigated in the subtropical Brisbane River-Moreton Bay estuary, Australia (27°25′S, 153°5′E). Bacterial communities were studied using automated rRNA intergenic spacer analysis (ARISA), which amplifies 16S-23S ribosomal DNA internally transcribed spacer regions from mixed-community DNA and detects the separated products on a fragment analyzer. Samples were collected from eight sites throughout the estuary and east to the East Australian Current (Co...

  20. Airport and airline choice in a multiple airport system: an empirical analysis for the San Fransisco Bay area

    NARCIS (Netherlands)

    Pels, E.; Nijkamp, P.; Rietveld, P.

    2001-01-01

    Pels E. Nijkamp P. and Rietveld P. (2001) Airport and airline choice in a multiple airport region: an empirical analysis for the San Francisco Bay area, Reg. Studies 35, 1-9. In this paper a nested logit model is used to describe passenger preferences concerning airports and airlines. A statistical

  1. The distribution and abundance of Sphaeroma terebrans, a wood-boring isopod of red mangrove (Rhizophora mangle) habitat within Tampa Bay

    Science.gov (United States)

    Brooks, R.A.; Bell, S.S.

    2005-01-01

    This study was conducted to determine the distribution, abundance, and demography of a wood boring isopod, Sphaeroma terebrans Bate, 1866, within the prop roots of the red mangrove, Rhizophora mangle L., in eight sites within Tampa Bay, Florida. Sphaeroma terebrans in Tampa Bay displayed reproductive activity year-round and bay-wide synchrony in their density pattern. On average approximately 60% (range: 25%-86%) of the intertidal aerial roots surveyed were occupied by S. terebrans. Although infestation levels by S. terebrans in Tampa Bay were similar to that of more tropical regions, the distribution of S. terebrans was not continuous throughout the study sites. A substantially higher occurrence and density of S. terebrans was found in the northern compared to more southern study sites within the Bay. Additionally, some seemingly suitable areas of the bay (i.e., Pinellas Point, Skyway, Fort Desoto) were actually unoccupied on some dates. Although sites differed in the frequency with which roots were attacked, the density of burrows and isopods in an occupied root was similar, with most attacked roots containing 3-5 burrows. The results of a transplantation experiment indicated that neither abiotic factors nor substrate quality limit the burrowing capabilities or survival of adult S. terebrans in the areas where they are absent. Instead, dispersal limitation, linked with differential juvenile survival, most likely controls isopod distribution and abundance within Tampa Bay.

  2. Meteorological Modeling Using the WRF-ARW Model for Grand Bay Intensive Studies of Atmospheric Mercury

    Directory of Open Access Journals (Sweden)

    Fong Ngan

    2015-02-01

    Full Text Available Measurements at the Grand Bay National Estuarine Research Reserve support a range of research activities aimed at improving the understanding of the atmospheric fate and transport of mercury. Routine monitoring was enhanced by two intensive measurement periods conducted at the site in summer 2010 and spring 2011. Detailed meteorological data are required to properly represent the weather conditions, to determine the transport and dispersion of plumes and to understand the wet and dry deposition of mercury. To describe the mesoscale features that might influence future plume calculations for mercury episodes during the Grand Bay Intensive campaigns, fine-resolution meteorological simulations using the Weather Research and Forecasting (WRF model were conducted with various initialization and nudging configurations. The WRF simulations with nudging generated reasonable results in comparison with conventional observations in the region and measurements obtained at the Grand Bay site, including surface and sounding data. The grid nudging, together with observational nudging, had a positive effect on wind prediction. However, the nudging of mass fields (temperature and moisture led to overestimates of precipitation, which may introduce significant inaccuracies if the data were to be used for subsequent atmospheric mercury modeling. The regional flow prediction was also influenced by the reanalysis data used to initialize the WRF simulations. Even with observational nudging, the summer case simulation results in the fine resolution domain inherited features of the reanalysis data, resulting in different regional wind patterns. By contrast, the spring intensive period showed less influence from the reanalysis data.

  3. AoA Region: South Asian Seas

    Digital Repository Service at National Institute of Oceanography (India)

    Naqvi, S.W.A.

    The South Asian Seas region lies in the northern extreme of the Indian Ocean. It includes the Arabian Sea and Bay of Bengal Large Marine Ecosystems (LME) along with their marginal basins as well as the Laccadive Sea and the Andaman Sea. Counties...

  4. Support for EU fundraising in the field of Environment & Energy - BayFOR

    Science.gov (United States)

    Ammerl, Thomas; Baumann, Cornelia; Reiter, Andrea; Blume, Andreas; Just, Jana; Franke, Jan

    2013-04-01

    The Bavarian Research Alliance (BayFOR, http://www.bayfor.org) is a private company for the support of Bavaria (Free State in the South East of Germany) as a centre for science and innovation within the European Research Area. It was set up on the initiative of the Bavarian universities to strengthen their networking at regional, national and international level while helping them to prepare to meet the requirements for European research funding. The focus is directed at the current EU Framework Programme (FP7) and the forthcoming Framework Programme for Research and Innovation "Horizon 2020", but also comprises the wide range of European programmes (e.g. FP7, LIFE+, Interreg, COST, EUREKA, ERA-Nets, IEE (CIP), LLP, Calls for tender). BayFOR is also a partner institution in the Bavarian "Haus der Forschung" (www.hausderforschung.bayern.de/en). BayFORs overall aim is to strengthen and permanently anchor the science and innovation location of Bavaria in the European Research Area through: a) Initiation of national and in particular European innovation and science partnerships from academia and business b) Improvement of innovation potential of Bavarian universities and SME c) Support in acquisition, management and dissemination of results of European and international projects in the field of research and technological development The service portfolio of the EU Funding Advisory Service reaches from the first project idea to project implementation. The minimum condition for BayFOR support is at least one partner from Bavaria (Germany) must be part of the applying consortium: a) Recommendation of funding programmes/instruments (incl. integration of relevant EU policies & directives) b) Partner search c) Project development and proposal elaboration (Online platform, Creation of consortium, Attendance at meetings, Preparation of documents, Proposal structure elaboration, Provision of templates, Editorial support: Gantt, PERT, Impact, EU added value) d) Support in the

  5. Organic Carbon and Trace Element Cycling in a River-Dominated Tidal Coastal Wetland System (Tampa Bay, FL, USA)

    Science.gov (United States)

    Moyer, R. P.; Smoak, J. M.; Engelhart, S. E.; Powell, C. E.; Chappel, A. R.; Gerlach, M. J.; Kemp, A.; Breithaupt, J. L.

    2016-02-01

    Tampa Bay is the largest open water, river-fed estuary in Florida (USA), and is characterized by the presence of both mangrove and salt marsh ecosystems. Both coastal wetland systems, and small rivers such as the ones draining into Tampa Bay have historically been underestimated in terms of their role in the global carbon and elemental cycles. Climate change and sea-level rise (SLR) are major threats in Tampa Bay and stand to disrupt hydrologic cycles, compromising sediment accumulation and the rate of organic carbon (OC) burial. This study evaluates organic carbon content, sediment accumulation, and carbon burial rates in salt marsh and mangrove ecosystems, along with measurements of fluxes of dissolved OC (DOC) and trace elements in the water column of the Little Manatee River (LMR) in Tampa Bay. The characterization of OC and trace elements in tidal rivers and estuaries is critical for quantitatively constraining these systems in local-to-regional scale biogeochemical budgets, and provide insight into biogeochemical processes occurring with the estuary and adjacent tidal wetlands. Material fluxes of DOC and trace elements were tied to discharge irrespective of season, and the estuarine habitats removed 15-65% of DOC prior to export to Tampa Bay and the Gulf of Mexico. Thus, material is available for cycling and burial within marsh and mangrove peats, however, LMR mangrove peats have higher OC content and burial rates than adjacent salt marsh peats. Sedimentary accretion rates in LMR marshes are not currently keeping pace with SLR, thus furthering the rapid marsh-to-mangrove conversions that have been seen in Tampa Bay over the past half-century. Additionally, wetlands in Tampa Bay tend to have a lower rate of carbon burial than other Florida tidal wetlands, demonstrating their high sensitivity to climate change and SLR.

  6. [The natural resources of the expedition bay as a basis for the creation of the health resort centre at the coast of the Peter the Great Bay, the Sea of Japan].

    Science.gov (United States)

    Vasil'chenko, V F; Badalov, N G; Derkacheva, L N

    2014-01-01

    The present article presents characteristics of the therapeutic and health promoting potential of the Expedition Bay, (part of the Peter the Great Bay, the Sea of Japan), known to be a deposit of therapeutic sea muds. The great variety of local therapeutic natural resources, viz. sea muds, sea weeds, friendly climate, beeches, etc., can be used for the treatment and prevention of various diseases. The Expedition Bay was designated as a local area of recreational and therapeutic value that can be used as a basis for the creation and further development of the multi-field health resort centre (or medical spa) that would attract patients from other regions of Russia and the surrounding countries. The future centre would provide medical services based in the first place on the classical methods of climatic and peloid therapy, thalassotherapy (heliotherapy, aeroionotherapy, bathing, marine algae therapy, etc.) as well as the modern balneotherapeutic and spa technologies, therapeutic tourism for the purpose of rehabilitation and health promotion.

  7. Urban Noise Modelling in Boka Kotorska Bay

    Directory of Open Access Journals (Sweden)

    Aleksandar Nikolić

    2014-04-01

    Full Text Available Traffic is the most significant noise source in urban areas. The village of Kamenari in Boka Kotorska Bay is a site where, in a relatively small area, road traffic and sea (ferry traffic take place at the same time. Due to the specificity of the location, i.e. very rare synergy of sound effects of road and sea traffic in the urban area, as well as the expressed need for assessment of noise level in a simple and quick way, a research was conducted, using empirical methods and statistical analysis methods, which led to the creation of acoustic model for the assessment of equivalent noise level (Leq. The developed model for noise assessment in the Village of Kamenari in Boka Kotorska Bay quite realistically provides data on possible noise levels at the observed site, with very little deviations in relation to empirically obtained values.

  8. MSL-1 reservicing in OPF Bay 1

    Science.gov (United States)

    2000-01-01

    KSC payloads processing employees work to reservice the Microgravity Science Laboratory-1 (MSL-1) Spacelab module in the Space Shuttle Orbiter Columbia's payload bay for the STS-94 mission in Orbiter Processing Facility 1. That mission is now scheduled to lift off in early July. This was the first time that this type of payload was reserviced without removing it from the payload bay. This new procedure pioneers processing efforts for quick relaunch turnaround times for future payloads. The Spacelab module was scheduled to fly again with the full complement of STS-83 experiments after that mission was cut short due to a faulty fuel cell. During the scheduled 16-day STS-94 mission, the experiments will be used to test some of the hardware, facilities and procedures that are planned for use on the International Space Station while the flight crew conducts combustion, protein crystal growth and materials processing experiments.

  9. New and Improved Results from Daya Bay

    CERN Multimedia

    CERN. Geneva

    2017-01-01

    Despite the great progress achieved in the last decades, neutrinos remain among the least understood fundamental particles to have been experimentally observed. The Daya Bay Reactor Neutrino Experiment consists of eight identically designed detectors placed underground at different baselines from three groups of nuclear reactors in China, a configuration that is ideally suited for studying the properties of these elusive particles. In this talk I will review the improved results released last summer by the Daya Bay collaboration. These results include (i) a precision measurement of the θ13 mixing angle and the effective mass splitting in the electron antineutrino disappearance channel with a dataset comprising more than 2.5 million antineutrino interactions, (ii) a high-statistics measurement of the absolute flux and spectrum of reactor-produced electron antineutrinos, and (iii) a search for light sterile neutrino mixing performed with more than three times the statistics of the previous result. I w...

  10. Stratification on the Skagit Bay Tidal Flats

    Science.gov (United States)

    2012-09-01

    shore Skagit Bay a Camano Island -1 0 1 -2-1012 0.5 -0.5 1 -1 C ro ss -s ho re (k m ) Alongshore (km) 0 b 1 0 -1 Bed level (m ) 18 2.2 Modeled...shadowed by Camano Island, which forms the southern border of the tidal flats (Fig. 2-3c). Saline water has propagated onshore and a roughly

  11. Bechevin Bay, Alaska, Inlet Stability Study.

    Science.gov (United States)

    1985-05-01

    Krenitzin. Bechevin Inlet, Bechevin Bay, and Isanotski Strait form an inlet system which * separates Unimak Island from the Alaska Peninsula. This...from the North Pacific must travel around Unimak Island through Unimak Pass. This route is 100-150 miles longer than the route through the Bechevin...period was semidiurnal, while the tidal flow at Unimak Pass (not too far southwest from the study area) was, interestingly, diurnal. Second, the phase

  12. IRST infrared background analysis of bay environments

    CSIR Research Space (South Africa)

    Schwering, PBW

    2008-04-01

    Full Text Available environment. Some sensor management approaches for application in IRST systems is discussed. Keywords: Infrared backgrounds, coastal bay analysis, small surface target contrasts, IRST application. 1. INTRODUCTION More and more, coastal... in environments with highly cluttered backgrounds as well as rapidly varying atmospheric conditions. Threat contrasts may be low and varying in littoral environments, and the amount of background clutter can be severe. Electro-optical sensors, used for detection...

  13. Distribution of Seagrasses in Inner Ambon Bay

    OpenAIRE

    Irawan, Andri; Nganro, Noorsalam R

    2016-01-01

    Excessive sedimentation in Inner Ambon Bay (IAB) is alleged to cause the degradation of seagrass ve-getation in the area. To get a clearer picture about the matter, we conducted a field study in October 2010 - January 2011 to describe the distribution and density of seagrass at several locations in IAB with different conditions of sedimentation levels. Data were collected using transects perpendicular to the coastline along the seagrass vegetation. The results showed that there were six speci...

  14. Experimental enhancement of pickleweed, Suisun Bay, California

    Science.gov (United States)

    Miles, A. Keith; Van Vuren, Dirk H.; Tsao, Danika C.; Yee, Julie L.

    2015-01-01

    As mitigation for habitat impacted by the expansion of a pier on Suisun Bay, California, two vehicle parking lots (0.36 ha and 0.13 ha) were restored by being excavated, graded, and contoured using dredged sediments to the topography or elevation of nearby wetlands. We asked if pickleweed (Sarcocornia pacifica L, [Amaranthaceae]) colonization could be enhanced by experimental manipulation on these new wetlands. Pickleweed dominates ecologically important communities at adjacent San Francisco Bay, but is not typically dominant at Suisun Bay probably because of widely fluctuating water salinity and is outcompeted by other brackish water plants. Experimental treatments (1.0-m2 plots) included mulching with pickleweed cuttings in either the fall or the spring, tilling in the fall, or applying organic enrichments in the fall. Control plots received no treatment. Pickleweed colonization was most enhanced at treatment plots that were mulched with pickleweed in the fall. Since exotic vegetation can colonize bare sites within the early phases of restoration and reduce habitat quality, we concluded that mulching was most effective in the fall by reducing invasive plant cover while facilitating native plant colonization.

  15. An overview of San Francisco Bay PORTS

    Science.gov (United States)

    Cheng, Ralph T.; McKinnie, David; English, Chad; Smith, Richard E.

    1998-01-01

    The Physical Oceanographic Real-Time System (PORTS) provides observations of tides, tidal currents, and meteorological conditions in real-time. The San Francisco Bay PORTS (SFPORTS) is a decision support system to facilitate safe and efficient maritime commerce. In addition to real-time observations, SFPORTS includes a nowcast numerical model forming a San Francisco Bay marine nowcast system. SFPORTS data and nowcast numerical model results are made available to users through the World Wide Web (WWW). A brief overview of SFPORTS is presented, from the data flow originated at instrument sensors to final results delivered to end users on the WWW. A user-friendly interface for SFPORTS has been designed and implemented. Appropriate field data analysis, nowcast procedures, design and generation of graphics for WWW display of field data and nowcast results are presented and discussed. Furthermore, SFPORTS is designed to support hazardous materials spill prevention and response, and to serve as resources to scientists studying the health of San Francisco Bay ecosystem. The success (or failure) of the SFPORTS to serve the intended user community is determined by the effectiveness of the user interface.

  16. Operational modal identification using variational Bayes

    Science.gov (United States)

    Li, Binbin; Der Kiureghian, Armen

    2017-05-01

    Operational modal analysis is the primary tool for modal parameter identification in civil engineering. Bayesian statistics offers an ideal framework for analyzing uncertainties associated with the identified modal parameters. However, the exact Bayesian formulation is usually intractable due to the high computational demand in obtaining the posterior distributions of modal parameters. In this paper, the variational Bayes method is employed to provide an approximate solution. Unlike the Laplace approximation and Monte Carlo sampling, the variational Bayes approach provides a gradient-free algorithm to analytically approximate the posterior distributions. Working with the state-space representation of a dynamical system, the variational Bayes approach for identification of modal parameters is derived by ignoring statistical correlation between latent variables and the model parameters. In this approach, the joint distribution of the state-transition and observation matrices as well as the joint distribution of the process noise and measurement error are firstly calculated analytically using conjugate priors. The distribution of modal parameters is extracted from these obtained joint distributions using a first-order Taylor series expansion. A robust implementation of the method is discussed by using square-root filtering and Cholesky decomposition. The proposed approach is illustrated by its application to an example mass-spring system and the One Rincon Hill Tower in San Francisco.

  17. Tidal power from the Bay of Fundy

    Energy Technology Data Exchange (ETDEWEB)

    van Walsum, W.

    1998-10-01

    The potential for tidal power development in New Brunswick`s Bay of Fundy was discussed. Alternative methods of tidal plant operation, suitable for the site conditions of the head of the Bay (where there are two continuous basins), were described. Tidal power is strongly influenced by site conditions. A simple mathematical model has shown that for the location at the head of the Bay, a linked-basins plant could produce 5 per cent more energy with only 53 per cent of the power generating machinery that would be required for a conventional paired basins scheme. The challenge is to find an economical, environmentally friendly way of extracting power and energy from the tides. An early study series from 1966 to 1988 has shown that tidal power can be economical, yet nothing has materialized beyond an 18 MW pilot plant at Annapolis because of environmental concerns. In 1977, this single basin tidal power plant was found to increase the tidal range at Boston by 30 cm. It was suggested that a `tidal fence` may be an ecologically acceptable solution to this problem. Attention was drawn to the need to draft a master plan for the development of Fundy`s tidal power potential, making sure that early development does not jeopardize optimum development of the total resource. 8 refs., 6 figs.

  18. Climate signals in Late Holocene sediments from Maxwell Bay and English Strait (South Shetland Islands, Antarctica)

    Science.gov (United States)

    Hass, H. Christian; Schröder, Simon; Kuhn, Gerhard

    2017-04-01

    Climate fluctuations of the past two millennia such as the Little Ice Age and the Medieval Warm Period are reported mainly from the Northern Hemisphere. Evidence from Antarctica is comparably sparse and reveals regional and temporal differences, which are particularly evident at the western and eastern sides of the Antarctic Peninsula. High-resolution coastal-marine sediment cores from the northernmost tip of the West Antarctic Peninsula reveal periods dominated by finer sediments between periods that lack the finer sediment component. In Maxwell Bay this fine sediment (grain size mode around 16 µm) has been traced back to sediment related to the occurrence of glacial meltwater. It was found in sheltered places and meltwater creeks of Potter Cove, a small tributary fjord to Maxwell Bay. In the sediment core this sediment occurs predominantly between 600 and 1250 AD (Medieval Warm Period) whereas it is only sparsely affecting the record between 1450 and 1900 AD (Little Ice Age). The temporal pattern is very similar to global-temperature reconstructions and even resembles temperature reconstructions from the Northern Hemisphere. To avoid local effects that may occur in Maxwell Bay more sediment cores were taken from bays and straits further south of King George Island during Cruise PS97 of RV "Polarstern" in 2016. A core from English Strait reveals completely different sedimentary conditions with no detectable meltwater signal (16 µm). However, the mean grain size record resembles that of the cores from Maxwell Bay. The lack of a clear-cut meltwater sediment class as it occurs further north is likely the result of a much smaller hinterland (Greenwich and Robert islands) when compared to Maxwell Bay between Nelson Island and the much bigger King George Island where glaciers and ice sheets discharge large quantities of very turbid meltwater directly into the bay. It is concluded that during the warmer climate periods a large amount of meltwater was released along the

  19. Water renewal in Montevideo's bay: a two compartments model for tritium kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Suarez-Antola, Roberto, E-mail: rsuarez@ucu.edu.uy [Universidad Catolica del Uruguay (UCU), Montevideo (Uruguay)

    2013-07-01

    During field work about dynamics and renewal of water in Montevideo's Bay, 100 Ci of tritiated water were evenly distributed in the north-east region of the bay, by a continuous injection of a solution, during 5 hours, from a 200 litres tank, using a peristaltic pump. The whole bay was divided in 20 concentration cells, taking into account available bathymetric charts and corrections from field data obtained in situ. Tritium concentrations (activities per unit volume) and other relevant parameters (temperature, electrical conductivity, etc.) were measured in vertical profiles during three weeks, in the mid-point of each cell, first twice a day and the on a daily basis. Remnant total tritium activity was estimated from cells volumes and midpoint cells activity concentrations. Consistency checks were done. A one compartment model was used to estimate a global renewal time of circa 29 hours. However, the details of the measured tritium kinetics, a careful consideration of bathymetric data, water movements in a tidal environment (measured with drogues, fluorescent tracers and current meters), as well as the results of computer fluid dynamics modelling (in depth averaged) suggests that the bay can be meaningfully divided in two main compartments: a North-East and a South-West compartment. The purpose of this paper is threefold: (1) to describe the construction of a two compartments model for water renewal in Montevideo's Bay, (2) to apply experimental data of tritium kinetics to estimate the parameters of the model, and (3) to discuss the validity of the model and its practical applicability. The meaning of the renewal time of each compartment and its relation with the measured tritium kinetics in each cell is discussed. The perturbations in water circulation and renewal produced by civil works already done or the perturbations that could be expected due to civil works to be done, in relation with Montevideo's harbour, is discussed. The tracer model

  20. Hydrodynamic modeling and feasibility study of harnessing tidal power at the Bay of Fundy

    Science.gov (United States)

    Chang, Jen

    Due to rising fuel costs and environmental concerns, energy generation from alternative power source has become one of the most important issues in energy policy. Tidal power is one of the alternative energy sources. The tidal range at the Bay of Fundy is the largest in the world (approximately 16 meters). It represents a prime location for harnessing tidal power using the daily rising and ebbing tide. In this study, a two dimensional finite element model has been developed and applied to simulate the tidal responses, including water level and flow velocity, in the Bay of Fundy region. The simulation results are used to choose the suitable location for energy development and to predict possible energy generated from different types of generation methods. Fluid motion is assumed to be governed by the shallow water equation since the wave length associated with tide is much longer than the water depth in the Bay of Fundy. By using a real time series of water elevation at the entrance of the bay, the computer model finds tidal response for each node in the study area, which is then verified by the observation record from several tidal gauge stations inside the bay. This study shows that the at-site cost of the energy for barrage type tidal power plants is around 0.065 to 0.097 per kWh at the recommended Shepody Bay, Cumberland Basin, and Cobequid Bay. The cost of energy for the current turbine type tidal power plants is 0.13/kWh to 0.24/kWh at the area with highest current velocity. Compared with the recent bill of the local power company, the at-site unit cost of energy from the barrage type of tidal power plant is feasible, but the environmental concerns of channel blocking by barrage present a formidable constraint. For the current turbine type of tidal power plant, even the most suitable sites are not financially feasible under current technology, but this type of power generation may become feasible as oil prices continue to increase and more efficient turbines

  1. Katabatic wind forcing of the Terra Nova Bay polynya

    Science.gov (United States)

    Bromwich, David H.; Kurtz, Dennis D.

    The Terra Nova Bay polynya is a perennial winter feature in the western Ross Sea, Antarctica, which occupies roughly 1000 km2, it is formed and maintained by the combined influence of persistent katabatic winds, which advect newly formed bay ice eastward, and the Drygalski Ice Tongue, which prevents northward drifting pack ice from entering Terra Nova Bay. Existence of anomalously strong katabatic drainage along this coast is predicted by Parish's (1982) simulation of wintertime airflow which reveals a pronounced confluence of surface winds upslope from the Reeves Glacier where the winds are further focused by local topography. The simulation is strongly supported by regional sastrugi orientations. Average wintertime atmospheric conditions and ice sheet topography which control surface air drainage are stable on a climatic time scale; therefore, persistent wintertime katabatic winds should be an annual phenomenon. Further evidence comes from multi-year Landsat images which consistently show windswept, snowfree areas on the Reeves Glacier. In marked contrast to typical Antarctic katabatic winds, strong persistent winter winds are observed at sea level ˜25 km beyond the coastal slope break. Air probably descends as bora-type winds and is likely to be significantly denser than the air at sea level; conditions are not favorable for hydraulic jumps apparently typical of other katabatic regimes. The horizontal density difference is maintained during airflow across the Nansen Ice Sheet because relatively little air mass modification occurs there in contrast to situations where air moves over an ice-laden ocean. Observations thus suggest that katabatic winds maintain their identity for some distance seaward of the coast; qualitative trajectory calculations indicate that for representative geostrophic conditions this distance is on the order of the observed polynya width. Estimated ice freezing rates are ˜20 cm day-1, but wind-generated waves and currents prevent ice from

  2. Interannual variation in the composition of the assemblages of medusae and ctenophores in St. Helena Bay, Southern Benguela Ecosystem

    Directory of Open Access Journals (Sweden)

    Emmanuelle Buecher

    2000-12-01

    Full Text Available The assemblages of medusae and ctenophores were examined from samples collected each winter from St Helena Bay, over the 10-year period 1988-1997. A total of 50 hydromedusae, 1 scyphozoan and 2 ctenophore species were identified from 243 samples. Although the data set is characterised by great interannual variability, two main assemblages could be identified each year. These were characterised by either holoplanktonic medusae (e.g. Liriope tetraphylla, Aglaura hemistoma or meroplanktonic medusae (e.g. Mitrocomella millardae, Chrysaora hysoscella and ctenophores (e.g. Pleurobrachia pileus. The holoplanktonic medusae were typical of samples at the southern edge of the Bay, and were positively associated with both depth and temperature. Their abundances tended to increase during warm years (1992, 1993 and 1997 as warm surface water flooded the Bay. The meroplanktonic medusae and ctenophores were typical of samples collected within the Bay, and the density of species tended to be negatively correlated with temperature and depth. In spite of the eurythermal nature of the meroplanktonic species, they were more common during cold years (1990 and 1995. This paper represents the first Bay-wide, interannual study of any zooplankton group, and contributes important base line information on the structure of regional pelagic assemblages.

  3. Evaluation of recent sedimentation rates in Guajara Bay (N Brazilian coast) with {sup 210}Pb and {sup 137}Cs

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Paulo A.L.; Neves, Patricia A.; Figueira, Rubens C.L., E-mail: paulo.alves.ferreira@usp.br, E-mail: ticinev@yahoo.com.br, E-mail: rfigueira@usp.br [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Instituto Oceanografico

    2013-07-01

    In the last 50 years the Amazon region suffered the negative effects of urban growth and industrial and agricultural development. Belem, capital city of the state of Para located, is one of its greatest urban centers, and, within its influence, Guajara Bay receives wastes discharges from Belem, which introduce many organic and inorganic contaminants to this bay. As the environmental accumulation of these pollutants is deeply related to intensity and volume of sediments deposition, this study aims to evaluate recent sedimentation rates (in a time range of 60 years) in Guajara Bay. By using high resolution gamma spectrometry, a nuclear technique proper for the analysis of radionuclides {sup 137}Cs and {sup 210}Pb, recent sedimentation rates were assessed in three sediment cores collected in 2011. The mean sedimentation rates found were 0.85 ± 0.12 cm yr{sup -1}for Anadim core, 1.02 ± 0.17 cm yr{sup -1}for Outeiro core and 0.53 ± 0.04 cm yr{sup -1}for Tucunduba core, which are within the range of expected values for systems such as bays, estuaries and lagoons with anthropic presence (the case of Guajara Bay). (author)

  4. Organic Matter Remineralization Predominates Phosphorus Cycling in the Mid-Bay Sediments in the Chesapeake Bay

    Energy Technology Data Exchange (ETDEWEB)

    Sunendra, Joshi R.; Kukkadapu, Ravi K.; Burdige, David J.; Bowden, Mark E.; Sparks, Donald L.; Jaisi, Deb P.

    2015-05-19

    The Chesapeake Bay, the largest and most productive estuary in the US, suffers from varying degrees of water quality issues fueled by both point and non–point source nutrient sources. Restoration of the bay is complicated by the multitude of nutrient sources, their variable inputs and hydrological conditions, and complex interacting factors including climate forcing. These complexities not only restrict formulation of effective restoration plans but also open up debates on accountability issues with nutrient loading. A detailed understanding of sediment phosphorus (P) dynamics enables one to identify the exchange of dissolved constituents across the sediment- water interface and aid to better constrain mechanisms and processes controlling the coupling between the sediments and the overlying waters. Here we used phosphate oxygen isotope ratios (δ18Op) in concert with sediment chemistry, XRD, and Mössbauer spectroscopy on the sediment retrieved from an organic rich, sulfidic site in the meso-haline portion of the mid-bay to identify sources and pathway of sedimentary P cycling and to infer potential feedback effect on bottom water hypoxia and surface water eutrophication. Isotope data indicate that the regeneration of inorganic P from organic matter degradation (remineralization) is the predominant, if not sole, pathway for authigenic P precipitation in the mid-bay sediments. We interpret that the excess inorganic P generated by remineralization should have overwhelmed any bottom-water and/or pore-water P derived from other sources or biogeochemical processes and exceeded saturation with respect to authigenic P precipitation. It is the first research that identifies the predominance of remineralization pathway against remobilization (coupled Fe-P cycling) pathway in the Chesapeake Bay. Therefore, these results are expected to have significant implications for the current understanding of P cycling and benthic-pelagic coupling in the bay, particularly on the

  5. Grand Bay-Banks Lake Stewardship Partnership - Phase 2

    Science.gov (United States)

    2006-11-01

    soils that are typically found beneath the wetlands. The Carolina bays are generally oval- shaped depressions and vary in size from one to several...layer of quartz sand, overlain by argillaceous, slightly phosphatic, dolomitic limestone. Small blue clasts of clay are common throughout the...McConnell and Hacke (1993) speculated that the circular shaped wetland areas called bays in the northern part of their study area (Grand Bay and Banks Lake

  6. The orbiter Discovery rolls from OPF bay 1 to bay 3

    Science.gov (United States)

    2000-01-01

    KSC employees chaperone the transfer of the orbiter Discovery from Orbiter Processing Facility (OPF) bay 1 to OPF bay 3 where ongoing payload and ground processing assessments will be completed. Managers will then determine when to roll the orbiter to the Vehicle Assembly Building for stacking with the external tank and solid rocket boosters, and when to roll out to Launch Pad 39A. Discovery is scheduled to launch Oct. 5 at 9:30 p.m. EDT on mission STS-92, which will be the 100th flight in the Shuttle program.

  7. Index for Assessing Water Trophic Status in Semi-Enclosed Cuban Bays. Case Study: Cienfuegos Bay

    CERN Document Server

    Seisdedo, Mabel; Arencibia, Gustavo

    2013-01-01

    This paper aims at contributing to the coastal environmental management by developing a new trophic status index of the water (TSIW). The index is tailored to semi-enclosed bays with estuarine characteristic like the Cienfuegos bay in Cuba. We also propose pressure indicators related to exporting and assimilation capacities as a tool to assess the vulnerability of the system to eutrophication. The TSIW is based on response indicators to eutrophication processes showing correspondence with the predefined pressure indicators and previous reports on water quality. Thus, the proposed trophic status index is a reliable scientific tool to measure the current stage of the water quality and to establish a baseline for further studies.

  8. Delineation of marsh types from Corpus Christi Bay, Texas, to Perdido Bay, Alabama, in 2010

    Science.gov (United States)

    Enwright, Nicholas M.; Hartley, Stephen B.; Couvillion, Brady R.; Michael G. Brasher,; Jenneke M. Visser,; Michael K. Mitchell,; Bart M. Ballard,; Mark W. Parr,; Barry C. Wilson,

    2015-07-23

    Coastal zone managers and researchers often require detailed information regarding emergent marsh vegetation types (that is, fresh, intermediate, brackish, and saline) for modeling habitat capacities and needs of marsh dependent taxa (such as waterfowl and alligator). Detailed information on the extent and distribution of emergent marsh vegetation types throughout the northern Gulf of Mexico coast has been historically unavailable. In response, the U.S. Geological Survey, in collaboration with the Gulf Coast Joint Venture, the University of Louisiana at Lafayette, Ducks Unlimited, Inc., and the Texas A&M University-Kingsville, produced a classification of emergent marsh vegetation types from Corpus Christi Bay, Texas, to Perdido Bay, Alabama.

  9. MODELING THE 1958 LITUYA BAY MEGA-TSUNAMI, II

    Directory of Open Access Journals (Sweden)

    Charles L. Mader

    2002-01-01

    Full Text Available Lituya Bay, Alaska is a T-Shaped bay, 7 miles long and up to 2 miles wide. The two arms at the head of the bay, Gilbert and Crillon Inlets, are part of a trench along the Fairweather Fault. On July 8, 1958, an 7.5 Magnitude earthquake occurred along the Fairweather fault with an epicenter near Lituya Bay.A mega-tsunami wave was generated that washed out trees to a maximum altitude of 520 meters at the entrance of Gilbert Inlet. Much of the rest of the shoreline of the Bay was denuded by the tsunami from 30 to 200 meters altitude.In the previous study it was determined that if the 520 meter high run-up was 50 to 100 meters thick, the observed inundation in the rest of Lituya Bay could be numerically reproduced. It was also concluded that further studies would require full Navier-Stokes modeling similar to those required for asteroid generated tsunami waves.During the Summer of 2000, Hermann Fritz conducted experiments that reproduced the Lituya Bay 1958 event. The laboratory experiments indicated that the 1958 Lituya Bay 524 meter run-up on the spur ridge of Gilbert Inlet could be caused by a landslide impact.The Lituya Bay impact landslide generated tsunami was modeled with the full Navier- Stokes AMR Eulerian compressible hydrodynamic code called SAGE with includes the effect of gravity.

  10. Coastal Habitat Restoration and Hydrodynamics in Panguil Bay, Philippines

    Science.gov (United States)

    Roxas, P. G.; Gorospe, J. G.

    2007-03-01

    Hydrobiological studies indicate the deterioration of the coastal ecosystems in Panguil Bay, Philippines despite interventions that started more than a decade ago. Mangrove ecosystems that filter land run offs and act as pollutant sinks are converted to fishponds that discharge toxic materials into the bay. Monsoon winds continue to erode mangrove-dominated coastlines. Water movements, nutrient transport and influx of freshwater from rivers and saline waters from the sea are altered by proliferating fishing structures and boats that use sea lanes for navigation. The reduction of current velocities increased siltation rates that caused shallowing of the bay. Failure in interventions to restore ecosystems is partly attributed to use of methods that failed to consider the bay's hydrodynamics. But sustaining the bay is a must because it is a major source of fishery resources hence strategies to arrest its further deterioration and to rehabilitate the degraded ecosystems based on the bay's hydrodynamics are explored. Timing, selection of appropriate species, and use of encasements are considered relative to the water dynamics of the bay. Zoning and regulation of barrier structures are implemented in some parts of the bay. Bioremediating agricultural run offs and discharges from fishponds, boats, and factories that accumulate in the inner part of the bay remains a challenge.

  11. PENERAPAN ALGORITMA NAIVE BAYES UNTUK MENGKLASIFIKASI DATA NASABAH ASURANSI

    Directory of Open Access Journals (Sweden)

    Bustami Bustami

    2014-01-01

    Full Text Available Data mining adalah teknik yang memanfaatkan data dalam jumlah yang besar untuk memperoleh informasi berharga yang sebelumnya tidak diketahui dan dapat dimanfaatkan untuk pengambilan keputusan penting. Pada penelitian ini, penulis berusaha menambang data (data mining nasabah sebuah perusahaan asuransi untuk mengetahui lancar, kurang lancar atau tidak lancarnya nasabah tersebut. Data yang ada dianalisis menggunakan algoritma Naive Bayes. Naive Bayes merupakan salah satu meode pada probabilistic reasoning. Algoritma Naive Bayes bertujuan untuk melakukan klasifikasi data pada kelas tertentu, kemudian pola tersebut dapat digunakan untuk memperkirakan nasabah yang bergabung, sehingga perusahaan bisa mengambil keputusan menerima atau menolak calon nasabah tersebut. Kata Kunci : data mining, asuransi, klasifikasi, algoritma Naive Bayes

  12. Assessment of relationship between rainfall and Escherichia coli in clams (Chamelea gallina using the Bayes Factor

    Directory of Open Access Journals (Sweden)

    Cesare Ciccarelli

    2017-08-01

    Full Text Available Consumption of bivalve shellfish harvested from water contaminated with sewage pollution presents a risk of human infections and targeting control measures require a good understanding of environmental factors influencing the transport and the fate of faecal contaminants within the hydrological catchments. Although there has been extensive development of regression models, the point of this paper, focused on the relationship between rainfall events and concentrations of Escherichia coli monitored in clams, was the use of a Bayesian approach, by the Bayes Factor. The study was conducted on clams harvested from the south coast of Marche Region (Italy, a coastal area impacted by continuous treated effluents, intermittent rainfalldependent untreated sewage spillage - as a consequence of stormwater overflowing - and rivers with an ephemeral flow regime. The work compared the different interpretation criteria of Bayes Factor, confirmed that E. coli concentrations in clams from the studied area varied in correlation with rainfall events, and demonstrated the effectiveness of Bayes Factor in the assessment of shellfish quality in coastal marine waters. However, it suggested that further investigations would be warranted to determine which environmental factors provide the better basis for accurate and timely predictions. Furthermore the gathered data could be useful, to the local authorities of Marche Region, in the definition of flexible monitoring programmes, taking into account the atmospheric events that could affect the correct functioning of sewage managing systems and the flow of tributary rivers.

  13. Genetic stock compositions and natal origin of green turtle (Chelonia mydas foraging at Brunei Bay

    Directory of Open Access Journals (Sweden)

    Juanita Joseph

    2016-04-01

    Full Text Available Knowledge of genetics composition and growth stages of endangered green turtles, as well as the connectivity between nesting and foraging grounds is important for effective conservation. A total of 42 green turtles were captured at Brunei Bay with curved carapace length ranging from 43.8 to 102.0 cm, and most sampled individuals were adults and large juveniles. Twelve haplotypes were revealed in mitochondrial DNA control region sequences. Most haplotypes contained identical sequences to haplotypes previously found in rookeries in the Western Pacific, Southeast Asia, and the Indian Ocean. Haplotype and nucleotide diversity indices of the Brunei Bay were 0.8444±0.0390 and 0.009350±0.004964, respectively. Mixed-stock analysis (for both uninformative and informative prior weighting by population size estimated the main contribution from the Southeast Asian rookeries of the Sulu Sea (mean ≥45.31%, Peninsular Malaysia (mean ≥17.42%, and Sarawak (mean ≥12.46%. Particularly, contribution from the Sulu Sea rookery was estimated to be the highest and lower confidence intervals were more than zero (≥24.36%. When estimating contributions by region rather than individual rookeries, results showed that Brunei Bay was sourced mainly from the Southeast Asian rookeries. The results suggest an ontogenetic shift in foraging grounds and provide conservation implications for Southeast Asian green turtles.

  14. Modeling and forecasting the distribution of Vibrio vulnificus in Chesapeake Bay.

    Science.gov (United States)

    Jacobs, J M; Rhodes, M; Brown, C W; Hood, R R; Leight, A; Long, W; Wood, R

    2014-11-01

    To construct statistical models to predict the presence, abundance and potential virulence of Vibrio vulnificus in surface waters of Chesapeake Bay for implementation in ecological forecasting systems. We evaluated and applied previously published qPCR assays to water samples (n = 1636) collected from Chesapeake Bay from 2007-2010 in conjunction with State water quality monitoring programmes. A variety of statistical techniques were used in concert to identify water quality parameters associated with V. vulnificus presence, abundance and virulence markers in the interest of developing strong predictive models for use in regional oceanographic modeling systems. A suite of models are provided to represent the best model fit and alternatives using environmental variables that allow them to be put to immediate use in current ecological forecasting efforts. Environmental parameters such as temperature, salinity and turbidity are capable of accurately predicting abundance and distribution of V. vulnificus in Chesapeake Bay. Forcing these empirical models with output from ocean modeling systems allows for spatially explicit forecasts for up to 48 h in the future. This study uses one of the largest data sets compiled to model Vibrio in an estuary, enhances our understanding of environmental correlates with abundance, distribution and presence of potentially virulent strains and offers a method to forecast these pathogens that may be replicated in other regions. This article has been contributed to by US Government employees and their work is in the public domain in the USA.

  15. GIS-based health assessment of the marine ecosystem in Laizhou Bay, China.

    Science.gov (United States)

    Song, Debin; Gao, Zhiqiang; Zhang, Hua; Xu, Fuxiang; Zheng, Xiangyu; Ai, Jinquan; Hu, Xiaoke; Huang, Guopei; Zhang, Haibo

    2017-08-17

    According to 2014-2016 monitoring data, an assessment index system including water quality, depositional environment and ecosystem was built to evaluate the health statue of marine ecosystem in the Laizhou Bay using analytic hierarchy process (AHP) method. The results, spatialized in ArcGIS software, show: while the comprehensive ecological health index is 0.62, the ecological environmental quality in the Laizhou Bay is in a sub-healthy state; the unhealthy area is mainly concentrated in southwestern inshore region, and impacted by serious environmental problems, such as water eutrophication and heavy metal pollution; the northwestern and southeastern inshore regions are in a sub-healthy state, while the eastern inshore and northern areas are in the healthiest state. The land-based pollutants that discharge into the sea may be the leading factors that are causing ecological environment deterioration in the Laizhou Bay, and the reclamation work ongoing around the port has exacerbated the ecological risk. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Towards Sustainable Ambon Bay: Evaluation of Solid Waste Management in Ambon City

    Science.gov (United States)

    Maryati, S.; Miharja, M.; Iscahyono, A. F.; Arsallia, S.; Humaira, AN S.

    2017-07-01

    Ambon Bay is a strategic area in the context of regional economic development, however it also faced environmental problems due to economic development and the growth of population. One of the environmental problems in the Ambon Bay is the growing solid waste which in turn lowers the quality of the water. The purpose of this study is to evaluate solid waste management in the Ambon City and propose recommendation in order to reduce solid waste in the Ambon Bay. The analytical method used is descriptive analysis by comparing a number of criteria based on the concept of solid waste management in coastal region with the current conditions of solid waste management in Ambon City. Criteria for waste management are divided into generation, storage, collection, transport, transfer and disposal. From the results of analysis, it can be concluded that the components of solid waste management at transport, transfer, and disposal level are generally still adequate, but solid waste management at source, storage and collection level have to be improved.

  17. Hawaii Regional Sediment Management Needs Assessment

    Science.gov (United States)

    2014-07-01

    Nukolii ( 2Waipouli 3 Kapaa 4 Lae Lipoa 5 Anahola 4 6 Kuaehu Point 7 Aliomanu 5 6 7 2 KILOMETERS 2 MILES - 95-percent confidence interval...of Kauai.1 The East Kauai region consists of the Nukolii, Waipouli, Kapaa, Lae Lipoa, Anahola, Kuaehu Point, and Aliomanu sub-regions (Figure 5...build a revetment. The County of Maui would like the owners to consider soft solutions to the problem. The Bay is a littoral cell with no exchange of

  18. Reducing methylmercury accumulation in the food webs of San Francisco Bay and its local watersheds

    Energy Technology Data Exchange (ETDEWEB)

    Davis, J.A., E-mail: jay@sfei.org [San Francisco Estuary Institute, 4911 Central Avenue, Richmond, CA 94804 (United States); Looker, R.E. [San Francisco Bay Regional Water Quality Control Board, 1515 Clay Street, Suite 1400, Oakland, CA 94612 (United States); Yee, D. [San Francisco Estuary Institute, 4911 Central Avenue, Richmond, CA 94804 (United States); Marvin-Di Pasquale, M. [U.S. Geological Survey, Water Resources Division/MS 480, 345 Middlefield Road, Menlo Park, CA 94025 (United States); Grenier, J.L. [San Francisco Estuary Institute, 4911 Central Avenue, Richmond, CA 94804 (United States); Austin, C.M. [San Francisco Bay Regional Water Quality Control Board, 1515 Clay Street, Suite 1400, Oakland, CA 94612 (United States); McKee, L.J.; Greenfield, B.K. [San Francisco Estuary Institute, 4911 Central Avenue, Richmond, CA 94804 (United States); Brodberg, R. [California Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, 1001 I Street, Sacramento, CA 95812 (United States); Blum, J.D. [Department of Geological Sciences, University of Michigan, 1100 North University Avenue, Ann Arbor, MI 48109 (United States)

    2012-11-15

    San Francisco Bay (California, USA) and its local watersheds present an interesting case study in estuarine mercury (Hg) contamination. This review focuses on the most promising avenues for attempting to reduce methylmercury (MeHg) contamination in Bay Area aquatic food webs and identifying the scientific information that is most urgently needed to support these efforts. Concern for human exposure to MeHg in the region has led to advisories for consumption of sport fish. Striped bass from the Bay have the highest average Hg concentration measured for this species in USA estuaries, and this degree of contamination has been constant for the past 40 years. Similarly, largemouth bass in some Bay Area reservoirs have some of the highest Hg concentrations observed in the entire US. Bay Area wildlife, particularly birds, face potential impacts to reproduction based on Hg concentrations in the tissues of several Bay species. Source control of Hg is one of the primary possible approaches for reducing MeHg accumulation in Bay Area aquatic food webs. Recent findings (particularly Hg isotope measurements) indicate that the decades-long residence time of particle-associated Hg in the Bay is sufficient to allow significant conversion of even the insoluble forms of Hg into MeHg. Past inputs have been thoroughly mixed throughout this shallow and dynamic estuary. The large pool of Hg already present in the ecosystem dominates the fraction converted to MeHg and accumulating in the food web. Consequently, decreasing external Hg inputs can be expected to reduce MeHg in the food web, but it will likely take many decades to centuries before those reductions are achieved. Extensive efforts to reduce loads from the largest Hg mining source (the historic New Almaden mining district) are underway. Hg is spread widely across the urban landscape, but there are a number of key sources, source areas, and pathways that provide opportunities to capture larger quantities of Hg and reduce loads

  19. Evaluating nonindigenous species management in a Bayesian networks derived relative risk framework for Padilla Bay, WA, USA.

    Science.gov (United States)

    Herring, Carlie E; Stinson, Jonah; Landis, Wayne G

    2015-10-01

    Many coastal regions are encountering issues with the spread of nonindigenous species (NIS). In this study, we conducted a regional risk assessment using a Bayesian network relative risk model (BN-RRM) to analyze multiple vectors of NIS introductions to Padilla Bay, Washington, a National Estuarine Research Reserve. We had 3 objectives in this study. The 1st objective was to determine whether the BN-RRM could be used to calculate risk from NIS introductions for Padilla Bay. Our 2nd objective was to determine which regions and endpoints were at greatest risk from NIS introductions. Our 3rd objective was to incorporate a management option into the model and predict endpoint risk if it were to be implemented. Eradication can occur at different stages of NIS invasions, such as the elimination of these species before being introduced to the habitat or removal of the species after settlement. We incorporated the ballast water treatment management scenario into the model, observed the risk to the endpoints, and compared this risk with the initial risk estimates. The model results indicated that the southern portion of the bay was at greatest risk because of NIS. Changes in community composition, Dungeness crab, and eelgrass were the endpoints most at risk from NIS introductions. The currents node, which controls the exposure of NIS to the bay from the surrounding marine environment, was the parameter that had the greatest influence on risk. The ballast water management scenario displayed an approximate 1% reduction in risk in this Padilla Bay case study. The models we developed provide an adaptable template for decision makers interested in managing NIS in other coastal regions and large bodies of water. © 2015 SETAC.

  20. A summer monsoon pump to keep the Bay of Bengal salty

    Digital Repository Service at National Institute of Oceanography (India)

    Vinayachandran, P.N.; Shankar, D.; Vernekar, S.; Sandeep, K.K.; Amol, P.; Neema, C.P.; Chatterjee, A.

    The Bay of Bengal receives a large influx of freshwater from precipitation and river discharge. Outflow of excess freshwater and inflow of saltier water is required to prevent the bay from freshening. Relatively fresh water flows out of the bay...

  1. Sediment depositional environment in some bays in Central west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Rajamanickam, G.V.; Gujar, A.R.

    minerals data show a positive correlation with mean grain size in Kalbadevi Bay but negative correlation in Ratnagiri Bay, whereas they show an unharmonic relationship with sorting. Considering similar hydraulic conditions in all the bays, the existence...

  2. San Francisco Bay National Wildlife Refuge Complex Annual Narrative Report 1981

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The San Francisco Bay National Wildlife Refuge Complex comprises of three refuges including the San Francisco Bay National Wildlife Refuge, the San Pablo Bay...

  3. On watermass mixing ratios and regenerated silicon in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Rao, D.P.; Sarma, V.V.; Rao, V.S.; Sudhakar, U.; Gupta, G.V.M.

    Regeneration of silicon on mixing in the Bay of Bengal have been computed from six water masses [Bay of Bengal low saline water (BBLS), Bay of Bengal subsurface water (BBSS), northern southeast high salinity water (NSEHS), north Indian intermediate...

  4. San Francisco Bay National Wildlife Refuge Complex Annual Narrative Report 1983

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The San Francisco Bay National Wildlife Refuge Complex comprises of three refuges including the San Francisco Bay National Wildlife Refuge, the San Pablo Bay...

  5. San Francisco Bay National Wildlife Refuge Complex Annual Narrative Report 1979

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The San Francisco Bay National Wildlife Refuge Complex comprises of three refuges including the San Francisco Bay National Wildlife Refuge, the San Pablo Bay...

  6. San Francisco Bay National Wildlife Refuge Complex Annual Narrative Report 1977

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The San Francisco Bay National Wildlife Refuge Complex comprises of three refuges including the San Francisco Bay National Wildlife Refuge, the San Pablo Bay...

  7. Ecological interactions of sea sponges (Animalia, Porifera according to artisanal fishermen from Camamu Bay, Bahia, Brazil

    Directory of Open Access Journals (Sweden)

    Loyana Docio

    2010-09-01

    Full Text Available This article represents the first ethnospongiological study in Brazil, and it aimed at recording artisanal fishermen’s knowledge about sea sponges and their ecological interactions. The study was carried out in the Ilha do Contrato community at Camamu Bay, Bahia State, Brazil. The data were obtained by means of open-ended interviews and projective tests, and followed the usual techniques of ethnographic surveys. The interviewees had knowledge regarding ecological interactions among fish, sea sponges and sponge endofaunal composition. According to the results, there is some congruence between folk wisdom and scientific knowledge. The importance of integrating local knowledge into management and conservation plans designed for the Camamu Bay region, as well as the set of data on ecology of reef communities, should be considered.

  8. Final Project Report, Bristol Bay Native Corporation Wind and Hydroelectric Feasibility Study

    Energy Technology Data Exchange (ETDEWEB)

    Vaught, Douglas J.

    2007-03-31

    The Bristol Bay Native Corporation (BBNC) grant project focused on conducting nine wind resource studies in eight communities in the Bristol Bay region of southwest Alaska and was administered as a collaborative effort between BBNC, the Alaska Energy Authority, Alaska Village Electric Cooperative, Nushagak Electric Cooperative (NEC), Naknek Electric Association (NEA), and several individual village utilities in the region. BBNC’s technical contact and the project manager for this study was Douglas Vaught, P.E., of V3 Energy, LLC, in Eagle River, Alaska. The Bristol Bay region of Alaska is comprised of 29 communities ranging in size from the hub community of Dillingham with a population of approximately 3,000 people, to a few Native Alaska villages that have a few tens of residents. Communities chosen for inclusion in this project were Dillingham, Naknek, Togiak, New Stuyahok, Kokhanok, Perryville, Clark’s Point, and Koliganek. Selection criteria for conduction of wind resource assessments in these communities included population and commercial activity, utility interest, predicted Class 3 or better wind resource, absence of other sources of renewable energy, and geographical coverage of the region. Beginning with the first meteorological tower installation in October 2003, wind resource studies were completed at all sites with at least one year, and as much as two and a half years, of data. In general, the study results are very promising for wind power development in the region with Class 6 winds measured in Kokhanok; Class 4 winds in New Stuyahok, Clark’s Point, and Koliganek; Class 3 winds in Dillingham, Naknek, and Togiak; and Class 2 winds in Perryville. Measured annual average wind speeds and wind power densities at the 30 meter level varied from a high of 7.87 meters per second and 702 watts per square meter in Kokhanok (Class 6 winds), to a low of 4.60 meters per second and 185 watts per square meter in Perryville (Class 2 winds).

  9. Management case study: Tampa Bay, Florida

    Science.gov (United States)

    Morrison, Gerold; Greening, Holly; Yates, Kimberly K.; Wolanski, Eric; McLusky, Donald S.

    2011-01-01

    Tampa Bay, Florida, USA, is a shallow, subtropical estuary that experienced severe cultural eutrophication between the 1940s and 1980s, a period when the human population of its watershed quadrupled. In response, citizen action led to the formation of a public- and private-sector partnership (the Tampa Bay Estuary Program), which adopted a number of management objectives to support the restoration and protection of the bay’s living resources. These included numeric chlorophyll a and water-clarity targets, as well as long-term goals addressing the spatial extent of seagrasses and other selected habitat types, to support estuarine-dependent faunal guilds. Over the past three decades, nitrogen controls involving sources such as wastewater treatment plants, stormwater conveyance systems, fertilizer manufacturing and shipping operations, and power plants have been undertaken to meet these and other management objectives. Cumulatively, these controls have resulted in a 60% reduction in annual total nitrogen (TN) loads relative to earlier worse-case (latter 1970s) conditions. As a result, annual water-clarity and chlorophyll a targets are currently met in most years, and seagrass cover measured in 2008 was the highest recorded since 1950. Factors that have contributed to the observed improvements in Tampa Bay over the past several decades include the following: (1) Development of numeric, science-based water-quality targets to meet a long-term goal of restoring seagrass acreage to 1950s levels. Empirical and mechanistic models found that annual average chlorophyll a concentrations were a primary manageable factor affecting light attenuation. The models also quantified relationships between TN loads, chlorophyll a concentrations, light attenuation, and fluctuations in seagrass cover. The availability of long-term monitoring data, and a systematic process for using the data to evaluate the effectiveness of management actions, has allowed managers to track progress and

  10. On the occurrence of ferromanganese micronodules from the sediments of the Bengal Fan: A high terrigenous sediment input region

    Digital Repository Service at National Institute of Oceanography (India)

    Chauhan, O.S.; Gujar, A.R.; Rao, Ch.M.

    Studies of 13 samples (10 surface sediments and 3 cores) from across the middle fan region of the Bay of Bengal reveal the presence of micronodules (area 0.22 million km@u2@@) over the entire bay. These micronodules have two dominant morphological...

  11. Dynamics of pink shrimp (Farfantepenaeus duorarum) recruitment potential in relation to salinity and temperature in Florida Bay

    Science.gov (United States)

    Browder, Joan A.; Zein-Eldin, Z.; Criales, Maria M.; Robblee, M.B.; Wong, S.; Jackson, Thomas L.; Johnson, D.

    2002-01-01

    Progress is reported in relating upstream water management and freshwater flow to Florida Bay to a valuable commercial fishery for pink shrimp (Farfantepenaeus duorarum), which has major nursery grounds in Florida Bay. Changes in freshwater inflow are expected to affect salinity patterns in the bay, so the effect of salinity and temperature on the growth, survival, and subsequent recruitment and harvest of this ecologically and economically important species was examined with laboratory experiments and a simulation model. Experiments were conducted to determine the response of juvenile growth and survival to temperature (15??C to 33??C) and salinity (2??? to 55???), and results were used to refine an existing model. Results of these experiments indicated that juvenile pink shrimp have a broad salinity tolerance range at their optimal temperature, but the salinity tolerance range narrows with distance from the optimal temperature range, 20-30??C. Acclimation improved survival at extreme high salinity (55???), but not at extremely low salinity (i.e., 5???, 10???). Growth rate increases with temperature until tolerance is exceeded beyond about 35??C. Growth is optimal in the mid-range of salinity (30???) and decreases as salinity increases or decreases. Potential recruitment and harvests from regions of Florida Bay were simulated based on local observed daily temperature and salinity. The simulations predict that potential harvests might differ among years, seasons, and regions of the bay solely on the basis of observed temperature and salinity. Regional differences in other characteristics, such as seagrass cover and tidal transport, may magnify regional differences in potential harvests. The model predicts higher catch rates in the September-December fishery, originating from the April and July settlement cohorts, than in the January-June fishery, originating from the October and January settlement cohorts. The observed density of juveniles in western Florida Bay

  12. Geological and geophysical evaluation of the mechanisms of the Great 1899 Yakutat Bay Earthquakes

    Science.gov (United States)

    Plafker, George; Thatcher, Wayne

    We have used tectonic, geologic, and seismologic observations to reevaluate the mechanisms and seismotectonic significance of the two great (Mw = 8.1 and 8.2) September 1899 Yakutat Bay earthquakes. In their comprehensive study of these earthquakes between 1905 and 1910, Tarr and Martin (1912) showed that these events were accompanied by shoreline changes in Yakutat Bay that ranged from 14.4 m emergence to 2.1 m submergence, uplift of about 1 m at Yakataga 160 km west of Yakutat Bay, and by several zones of surface fissures on land. Although major earthquake faults were not found, Tarr and Martin postulated that the shoreline displacements were caused by vertical movements on a system of concealed steep normal faults and that the fissure zones on ridges were along subsidiary faults. Our geologic studies in the Yakutat Bay region indicate that: (1) the emergent shorelines along Yakutat Bay define a broad upwarp roughly 50 km × 30 km that is primarily related to reverse slip on local concealed shallowly dipping thrust faults; (2) the reported subsidence was due largely, or entirely, to nontectonic surficial submergence of unconsolidated deposits; and (3) most, if not all, of the zones of surface fractures related to the 1899 earthquakes are "sackung" that were probably caused by large-scale gravitational slumping of steep slopes, rather than faulting. A small number of early damped seismograms and the vertical uplift data were used to constrain the fault slippage that occurred during the two great earthquakes of 1899. Seismic moments determined from 50-s surface wave amplitudes are ˜2 × 1021 N m for these two events, equivalent to Mw 8.1. Uplift determined from raised shorelines within Yakutat Bay can be accounted for by the 10 September event alone, and these data can be fit by ˜10- to 20-m dip slippage on three dextral oblique thrust faults that dip ˜30° northeast or north. Faulting complexity is also shown by the S-wave seismogram of the 10 September shock

  13. Commencement Bay Study. Volume IV. Invertebrates.

    Science.gov (United States)

    1981-12-31

    AD-AI12 555 DAMES AND MOORE SEATTLE WA* FIG 8/1 COMMENCEMENT BAY STUDY. VOLUME IV. INVERTEBRATES .(U)DEC 81 W M BAYLOCK, J P HOUGHTON DACW67-80-C-OIDI...December 1981 Volume IV, Invertebrates 6. PERFORMINO ORG. REPORT NUMBER 682-021-05 7. AUTHOR(*) S. CONTRACT OR GRANT NUmaER(S) DACW67-80-C-0101 S. PERFORMING... Invertebrates Air Quality, Birds Is. KEY WORDS (Continue an reverse old. It necomemy w red ty a b eek mireber) Salmonids Wetlands Noise Aesthetics Marine Fish

  14. Bathymetry and acoustic backscatter: Estero Bay, California

    Science.gov (United States)

    Hartwell, Stephen R.; Finlayson, David P.; Dartnell, Peter; Johnson, Samuel Y.

    2013-01-01

    Between July 30 and August 9, 2012, scientists from the U.S. Geological Survey (USGS), Pacific Coastal and Marine Science Center (PCMSC), acquired bathymetry and acoustic-backscatter data from Estero Bay, San Luis Obispo, California, under PCMSC Field Activity ID S-05-12-SC. The survey was done using the R/V Parke Snavely outfitted with a multibeam sonar for swath mapping and highly accurate position and orientation equipment for georeferencing. This report provides these data in a number of different formats, as well as a summary of the mapping mission, maps of bathymetry and backscatter, and Federal Geographic Data Committee (FGDC) metadata.

  15. Minimum relative entropy, Bayes and Kapur

    Science.gov (United States)

    Woodbury, Allan D.

    2011-04-01

    The focus of this paper is to illustrate important philosophies on inversion and the similarly and differences between Bayesian and minimum relative entropy (MRE) methods. The development of each approach is illustrated through the general-discrete linear inverse. MRE differs from both Bayes and classical statistical methods in that knowledge of moments are used as ‘data’ rather than sample values. MRE like Bayes, presumes knowledge of a prior probability distribution and produces the posterior pdf itself. MRE attempts to produce this pdf based on the information provided by new moments. It will use moments of the prior distribution only if new data on these moments is not available. It is important to note that MRE makes a strong statement that the imposed constraints are exact and complete. In this way, MRE is maximally uncommitted with respect to unknown information. In general, since input data are known only to within a certain accuracy, it is important that any inversion method should allow for errors in the measured data. The MRE approach can accommodate such uncertainty and in new work described here, previous results are modified to include a Gaussian prior. A variety of MRE solutions are reproduced under a number of assumed moments and these include second-order central moments. Various solutions of Jacobs & van der Geest were repeated and clarified. Menke's weighted minimum length solution was shown to have a basis in information theory, and the classic least-squares estimate is shown as a solution to MRE under the conditions of more data than unknowns and where we utilize the observed data and their associated noise. An example inverse problem involving a gravity survey over a layered and faulted zone is shown. In all cases the inverse results match quite closely the actual density profile, at least in the upper portions of the profile. The similar results to Bayes presented in are a reflection of the fact that the MRE posterior pdf, and its mean

  16. Integration of bed characteristics, geochemical tracers, current measurements, and numerical modeling for assessing the provenance of beach sand in the San Francisco Bay Coastal System

    Science.gov (United States)

    Barnard, Patrick L.; Foxgrover, Amy C.; Elias, Edwin P.L.; Erikson, Li H.; Hein, James R.; McGann, Mary; Mizell, Kira; Rosenbauer, Robert J.; Swarzenski, Peter W.; Takesue, Renee K.; Wong, Florence L.; Woodrow, Donald L.; Barnard, P.L.; Jaffee, B.E.; Schoellhamer, D.H.

    2013-01-01

    Over 150 million m3 of sand-sized sediment has disappeared from the central region of the San Francisco Bay Coastal System during the last half century. This enormous loss may reflect numerous anthropogenic influences, such as watershed damming, bay-fill development, aggregate mining, and dredging. The reduction in Bay sediment also appears to be linked to a reduction in sediment supply and recent widespread erosion of adjacent beaches, wetlands, and submarine environments. A unique, multi-faceted provenance study was performed to definitively establish the primary sources, sinks, and transport pathways of beach-sized sand in the region, thereby identifying the activities and processes that directly limit supply to the outer coast. This integrative program is based on comprehensive surficial sediment sampling of the San Francisco Bay Coastal System, including the seabed, Bay floor, area beaches, adjacent rock units, and major drainages. Analyses of sample morphometrics and biological composition (e.g., Foraminifera) were then integrated with a suite of tracers including 87Sr/86Sr and 143Nd/144Nd isotopes, rare earth elements, semi-quantitative X-ray diffraction mineralogy, and heavy minerals, and with process-based numerical modeling, in situ current measurements, and bedform asymmetry to robustly determine the provenance of beach-sized sand in the region.

  17. Comparative accounts of biological productivity characteristics and estimates of carbon fluxes in the Arabian Sea and the Bay of Bengal

    Science.gov (United States)

    Gauns, Mangesh; Madhupratap, M.; Ramaiah, N.; Jyothibabu, R.; Fernandes, Veronica; Paul, Jane T.; Prasanna Kumar, S.

    2005-07-01

    The Arabian Sea and the Bay of Bengal are tropical basins experiencing monsoonal wind forcing that reverses semi-annually. This brings changes in physics, chemistry and biology of the upper water column on a seasonal scale and ultimately regulates the sinking fluxes of the region. An attempt is made here to focus on factors responsible for fluxes of carbon from the upper layers to the deep sea. Higher fluxes are observed during southwest and northeast monsoon season in both the regions. In contrast to the Arabian Sea, an immense quantity of freshwater runoff together with warmer SST (˜30 °C) makes the northern bay strongly stratified. The runoff also brings in billions of tonnes of fluvial matter as well. Stratification constrains subsurface nutrient input into the surface waters thereby reducing the primary production in the Bay of Bengal. The total living carbon content in the Bay of Bengal is much lower than in the Arabian Sea. Higher downward fluxes associated with deep mixed layer and high production in the Arabian Sea during summer and winter pinpoint importance of strong winds causing mixing and upwelling during summer and evaporative cooling and convection during winter. Inability of the low-speed winds to break the stratification in the Bay of Bengal keeps the region low productive throughout the year. Therefore, river water associated with the terrigenous material due to ballast effect appears to swipe off surface producers to the deep, thereby increasing the downward fluxes of total particulates, which are sometimes even higher than that of the more productive Arabian Sea.

  18. Intertidal sediments and benthic animals of Roebuck Bay, Western Australia

    NARCIS (Netherlands)

    Pepping, M.; Piersma, T.; Pearson, G.; Lavaleye, M.

    1999-01-01

    Roebuck Bay near Broome (NW Australia) is with itsextensive tidal flats one of the foremost internationallyimportant sites for shorebirds in the Asia-Pacificflyway system. It is home to 150,000 shorebirds (or‘waders’) in the nonbreeding season, which suggeststhat the intertidal flats of the bay have

  19. Summer survival of Phytophthora ramorum in California bay laurel leaves

    Science.gov (United States)

    Elizabeth J. Fichtner; David M. Rizzo; Shannon C. Lynch; Jennifer Davidson; Gerri Buckles; Jennifer Parker

    2008-01-01

    Sudden oak death manifests as non-lethal foliar lesions on bay laurel (Umbellularia californica), which support sporulation and survival of Phytophthora ramorum in forest ecosystems. Infected bay laurel leaves are more likely to abscise than uninfected leaves, resulting in an accumulation of inoculum at the forest floor. The pathogen survives the dry...

  20. 33 CFR 117.795 - Jamaica Bay and Connecting Waterways.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Jamaica Bay and Connecting Waterways. 117.795 Section 117.795 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New York § 117.795 Jamaica Bay and...

  1. St Helena Bay (southern Benguela) then and now: muted climate ...

    African Journals Online (AJOL)

    ... the abiotic and biotic components. St Helena Bay in the 1950s showed similarities to 2000–2010 in terms of wind patterns, hydrology and phytoplankton. Upwelling, oxygen and nutrient concentrations in subthermocline water displayed pronounced decadal-scale variability. Primary production in St Helena Bay is variable ...

  2. Flood Risk Mitigation for the Jamaica Bay Area

    NARCIS (Netherlands)

    Aarnink, J.L.; De Boer, R.; Evers, G.A.; Kruis, M.C.; Van der Valk, K.

    2014-01-01

    Project Jamaica Bay is a response to superstorm Sandy, occurring in October, 2012. The storm was a disaster for New York City, causing around 50 billion US dollars of damage. Research shows that 75% of the expected annual dam-age in New York occurs around the Jamaica Bay area. Another problem that

  3. An overview of the Daya Bay Reactor Neutrino Experiment

    CERN Document Server

    Cao, Jun

    2016-01-01

    The Daya Bay Reactor Neutrino Experiment discovered an unexpectedly large neutrino oscillation related to the mixing angle $\\theta_{13}$ in 2012. This finding paved the way to the next generation of neutrino oscillation experiments. In this article, we review the history, featured design, and scientific results of Daya Bay. Prospects of the experiment are also described.

  4. An overview of the Daya Bay reactor neutrino experiment

    OpenAIRE

    Cao, Jun; Luk, Kam-Biu

    2016-01-01

    The Daya Bay Reactor Neutrino Experiment discovered an unexpectedly large neutrino oscillation related to the mixing angle $\\theta_{13}$ in 2012. This finding paved the way to the next generation of neutrino oscillation experiments. In this article, we review the history, featured design, and scientific results of Daya Bay. Prospects of the experiment are also described.

  5. Modelling of hydrodynamic circulation in Benoa Bay, Bali

    DEFF Research Database (Denmark)

    Ningsih, Nining Sari; Muchamad, Al Azhar

    2013-01-01

    A simulation of water level, velocity, salinity, and temperature in the Bay of Benoa has been carried out using a three-dimensional hydrodynamic Estuarine and Coastal Ocean Model incorporating a main characteristic of southward transport of the Indonesian throughflow at the offshore area of the bay...

  6. eBay's Business Format: An example of Participatory Democracy ...

    African Journals Online (AJOL)

    Here, I analyzed the eBay business model and compared the user agreements and texts among eBay, Sothebys, PayPal and Paisa Pay. Further, an analysis of Indian jurisprudence on online auctioneer liability and the subsequent legislation was performed to determine the impact of the business model on a developing ...

  7. A support system for predicting eBay end prices.

    NARCIS (Netherlands)

    D.P. van Heijst (Dennis); R. Potharst (Rob); M.C. van Wezel (Michiel)

    2006-01-01

    textabstractIn this report a support system for predicting end prices on eBay is proposed. The end price predictions are based on the item descriptions found in the item listings of eBay, and on some numerical item features. The system uses text mining and boosting algorithms from the field of

  8. 27 CFR 9.157 - San Francisco Bay.

    Science.gov (United States)

    2010-04-01

    ..., San Mateo, Santa Clara, Alameda, and Contra Costa, which border the San Francisco Bay. The area also... proceed along the San Francisco, San Mateo, and Santa Cruz County shoreline (across the Quadrangles of San... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false San Francisco Bay. 9.157...

  9. 33 CFR 80.110 - Casco Bay, ME.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Casco Bay, ME. 80.110 Section 80.110 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Atlantic Coast § 80.110 Casco Bay, ME. (a) A line drawn from the...

  10. Characteristic mixing triangles in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Varkey, M.J.; Sastry, J.S.

    Temperature-salinity structures in the inner part of Bay of Bengal showed complete mixing processes in the upper bay, less than about 600 m can be characterisEd. by a mixing triangle constitutEd. by three characteristic water properties. In outer...

  11. 33 CFR 334.80 - Narragansett Bay, RI; restricted area.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Narragansett Bay, RI; restricted..., DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.80 Narragansett Bay, RI; restricted... regulations in this section shall be enforced by the Commander U.S. Naval Base, Newport, RI, and such agencies...

  12. Using naive Bayes classifier for classification of convective rainfall ...

    Indian Academy of Sciences (India)

    ... based on 'naiveBayes classifier' is applied. This is a simple probabilistic classifier based on applying 'Bayes' theoremwith strong (naive) independent assumptions. For a 9-month period, the ability of SEVIRI to classifythe rainfall intensity in the convective clouds is evaluated using weather radar over the northern Algeria.

  13. Great Knot Calidris tenuirostris at Lutembe Bay, Uganda

    African Journals Online (AJOL)

    Lutembe bay is a sheltered shallow bay on the northern shores of Lake Victoria near. Entebbe International Airport with scattered mud islands often covered by water hyacinth. It has many Palaearctic migrants, particularly huge congregations of gulls and terns. Interesting species such as Caspian Tern Sterna caspia, ...

  14. Upwelling features near Sri Lanka in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    ShreeRam, P.; Rao, L.V.G.

    The Bay of Bengal is a semi-enclosed tropical ocean basin that is highly influenced by monsoons and receives large volume of freshwater from both river discharge and rainfall. Over the Bay of Bengal two distinct wind systems prevail during the year...

  15. 33 CFR 110.193 - Tampa Bay, Fla.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Tampa Bay, Fla. 110.193 Section 110.193 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS Anchorage Grounds § 110.193 Tampa Bay, Fla. (a) The anchorage grounds—(1) Explosives...

  16. 33 CFR 110.193a - St. Joseph Bay, Fla.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false St. Joseph Bay, Fla. 110.193a Section 110.193a Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS Anchorage Grounds § 110.193a St. Joseph Bay, Fla. (a) The anchorage grounds—(1...

  17. Dynamics of macrozoobenthos assemblages in the Fubao Bay of ...

    African Journals Online (AJOL)

    A two-year-long investigation on the dynamics of the structure and biodiversity of macrozoobenthos was conducted in the Fubao Bay of Dianchi Lake, Southwest China. A high level of organic pollution has been detected in this Bay for the last 10 years. In all, 31 benthic taxa belonging to eight families and 20 genera were ...

  18. 33 CFR 117.779 - Eastchester Bay (Arm of).

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Eastchester Bay (Arm of). 117.779 Section 117.779 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New York § 117.779 Eastchester Bay (Arm of). The draw...

  19. 46 CFR 7.110 - Mamala Bay, HI.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Mamala Bay, HI. 7.110 Section 7.110 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES APPLICABLE TO THE PUBLIC BOUNDARY LINES Hawaii § 7.110 Mamala Bay, HI. A line drawn from Barbers Point Light to Diamond Head Light. Pacific Coast ...

  20. 33 CFR 80.1430 - Kaneohe Bay, Oahu, HI.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Kaneohe Bay, Oahu, HI. 80.1430 Section 80.1430 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Islands § 80.1430 Kaneohe Bay, Oahu, HI. A straight line...

  1. 33 CFR 80.1420 - Mamala Bay, Oahu, HI.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Mamala Bay, Oahu, HI. 80.1420 Section 80.1420 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Islands § 80.1420 Mamala Bay, Oahu, HI. A line drawn from...

  2. Green Bay: Spatial patterns in water quality and landscape correlations

    Science.gov (United States)

    We conducted a high-resolution survey along the nearshore (369 km) in Green Bay using towed electronic instrumentation at approximately the 15 m depth contour, with additional transects of the bay that were oriented cross-contour (49 km). Electronic sensor data provided an effic...

  3. Optimasi Naive Bayes Dengan Pemilihan Fitur Dan Pembobotan Gain Ratio

    Directory of Open Access Journals (Sweden)

    I Guna Adi Socrates

    2016-03-01

    Full Text Available Naïve Bayes merupakan salah satu metode data mining yang umum digunakan dalam klasifikasi dokumen berbasis text. Kelebihan dari metode ini adalah algoritma yang sederhana dengan  kompleksitas  perhitungan  yang  rendah.  Akan  tetapi,  pada  metode  Naïve  Bayes terdapat kelemahan dimana sifat independensi dari fitur Naïve Bayes tidak dapat selalu diterapkan sehingga akan berpengaruh pada tingkat akurasi perhitungan. Maka dari itu, metode Naïve Bayes perlu dioptimasi dengan cara pemberian bobot mengunakan Gain Ratio. Namun, pemberian bobot pada Naïve Bayes menimbulkan permasalahan pada penghitungan probabilitas setiap    dokumen, dimana fitur  yang tidak  merepresentasikan kelas  yang diuji banyak muncul sehingga terjadi kesalahan klasifikasi. Oleh karena itu, pembobotan Naïve Bayes   masih   belum   optimal.   Paper   ini mengusulkan  optimasi  metode   Naïve   Bayes mengunakan pembobotan Gain Ratio yang ditambahkan dengan metode pemilihan fitur pada kasus klasifikasi teks. Hasil penelitian ini menunjukkan bahwa optimasi metode Naïve Bayes menggunakan pemilihan fitur dan pembobotan menghasilkan akurasi sebesar 94%.

  4. Numerical study of tsunami generated by multiple submarine slope failures in Resurrection Bay, Alaska, during the MW 9.2 1964 earthquake

    Science.gov (United States)

    Suleimani, E.; Hansen, R.; Haeussler, P.J.

    2009-01-01

    We use a viscous slide model of Jiang and LeBlond (1994) coupled with nonlinear shallow water equations to study tsunami waves in Resurrection Bay, in south-central Alaska. The town of Seward, located at the head of Resurrection Bay, was hit hard by both tectonic and local landslide-generated tsunami waves during the MW 9.2 1964 earthquake with an epicenter located about 150 km northeast of Seward. Recent studies have estimated the total volume of underwater slide material that moved in Resurrection Bay during the earthquake to be about 211 million m3. Resurrection Bay is a glacial fjord with large tidal ranges and sediments accumulating on steep underwater slopes at a high rate. Also, it is located in a seismically active region above the Aleutian megathrust. All these factors make the town vulnerable to locally generated waves produced by underwater slope failures. Therefore it is crucial to assess the tsunami hazard related to local landslide-generated tsunamis in Resurrection Bay in order to conduct comprehensive tsunami inundation mapping at Seward. We use numerical modeling to recreate the landslides and tsunami waves of the 1964 earthquake to test the hypothesis that the local tsunami in Resurrection Bay has been produced by a number of different slope failures. We find that numerical results are in good agreement with the observational data, and the model could be employed to evaluate landslide tsunami hazard in Alaska fjords for the purposes of tsunami hazard mitigation. ?? Birkh??user Verlag, Basel 2009.

  5. Supply and dispersal of flood sediment from a steep, tropical watershed: Hanalei Bay, Kaua'i, Hawai'i, USA

    Science.gov (United States)

    Draut, A.E.; Bothner, Michael H.; Field, M.E.; Reynolds, R.L.; Cochran, S.A.; Logan, J.B.; Storlazzi, C.D.; Berg, C.J.

    2009-01-01

    In contrast to many small, mountainous watersheds in temperate coastal regions, where fluvial discharge and wave energy commonly coincide, deposition and reworking of tropical flood sediment can be seasonally decoupled, and this has important implications for coral-reef ecosystems. An understanding of the interaction between tropical flood sedimentation and wave climate is essential to identifying and mitigating effects of watershed changes on coral reefs as urbanization and climate change proceed. Sedimentary facies and isotopic properties of sediment in Hanalei Bay, on the island of Kaua'i, Hawai'i, USA, were used to assess deposition and reworking of flood deposits from the Hanalei River in a case study demonstrating the potential ecosystem effects of runoff from a steep, tropical watershed. In Hanalei Bay, the youngest and thickest terrigenous sediment was consistently present near the river mouth and in a bathymetric depression that acted as at least a temporary sediment sink. During this 2 yr study, the largest flood events occurred in late winter and spring 2006; substantial terrestrial sediment delivered by those floods still remained in the bay as of June 2006 because oceanic conditions were not sufficiently energetic to transport all of the sediment offshore. Additional sediment was deposited in the bay by a summer 2006 flood that coincided with seasonal low wave energy. In most years, flood sediment accumulating in the bay and on its fringing reefs would be remobilized and advected out of the bay during winter, when the wave climate is energetic. Turbidity and sedimentation on corals resulting from late spring and summer floods during low wave energy could have a greater impact on coral-reef ecosystems than floods in other seasons, an effect that could be exacerbated if the incidence and sediment load of tropical summer floods increase due to urbanization and climate change. ?? 2008 Geological Society of America.

  6. Analysis of modern and Pleistocene hydrologic exchange between Saginaw Bay (Lake Huron) and the Saginaw Lowlands area

    Science.gov (United States)

    Hoaglund, J. R.; Kolak, J.J.; Long, D.T.; Larson, G.J.

    2004-01-01

    Two numerical models, one simulating present groundwater flow conditions and one simulating ice-induced hydraulic loading from the Port Huron ice advance, were used to characterize both modern and Pleistocene groundwater exchange between the Michigan Basin and near-surface water systems of Saginaw Bay (Lake Huron) and the surrounding Saginaw Lowlands area. These models were further used to constrain the origin of saline, isotopically light groundwater, and porewater from the study area. Output from the groundwater-flow model indicates that, at present conditions, head in the Marshall aquifer beneath Saginaw Bay exceeds the modern lake elevation by as much as 21 m. Despite this potential for flow, simulated groundwater discharge through the Saginaw Bay floor constitutes only 0.028 m3 s-1 (???1 cfs). Bedrock lithology appears to regulate the rate of groundwater discharge, as the portion of the Saginaw Bay floor underlain by the Michigan confining unit exhibits an order of magnitude lower flux than the portion underlain by the Saginaw aquifer. The calculated shoreline discharge of groundwater to Saginaw Bay is also relatively small (1.13 m3 s-1 or ???40 cfs) because of low gradients across the Saginaw Lowlands area and the low hydraulic conductivities of lodgement tills and glacial-lake clays surrounding the bay. In contrast to the present groundwater flow conditions, the Port Huron ice-induced hydraulic-loading model generates a groundwater-flow reversal that is localized to the region of a Pleistocene ice sheet and proglacial lake. This area of reversed vertical gradient is largely commensurate with the distribution of isotopically light groundwater presently found in the study area. Mixing scenarios, constrained by chloride concentrations and ??18O values in porewater samples, demonstrate that a mixing event involving subglacial recharge could have produced the groundwater chemistry currently observed in the Saginaw Lowlands area. The combination of models and

  7. Under the Golden Gate bridge: views of the sea floor near the entrance to San Francisco Bay, California

    Science.gov (United States)

    Dartnell, Peter; Barnard, Patrick L.; Chin, John L.; Hanes, Daniel; Kvitek, Rikk G.; Iampietro, Pat J.; Gardner, James V.

    2006-01-01

    San Francisco Bay in Northern California is one of the largest and most altered estuaries within the United States. The sea floor within the bay as well as at its entrance is constantly changing due to strong tidal currents, aggregate mining, dredge disposal, and the creation of new land using artificial fill. Understanding this dynamic sea floor is critical for addressing local environmental issues, which include defining pollution transport pathways, deciphering tectonics, and identifying benthic habitats. Mapping commercial interests such as safe ship navigation and dredge disposal is also significantly aided by such understanding. Over the past decade, the U.S. Geological Survey (USGS), the National Oceanic and Atmospheric Administration (NOAA), and California State University, Monterey Bay (CSUMB) in cooperation with the U.S. Army Corps of Engineers (USACOE) and the Center for Integrative Coastal Observation, Research and Education (CICORE) have partnered to map central San Francisco Bay and its entrance under the Golden Gate Bridge using multibeam echosounders. These sonar systems can continuously map to produce 100 percent coverage of the sea floor at meter-scale resolution and thus produce an unprecedented view of the floor of the bay. This poster shows views of the sea floor in west-central San Francisco Bay around Alcatraz and Angel Islands, underneath the Golden Gate Bridge, and through its entrance from the Pacific Ocean. The sea floor is portrayed as a shaded relief surface generated from the multibeam data color-coded for depth from light blues for the shallowest values to purples for the deepest. The land regions are portrayed by USGS digital orthophotographs (DOQs) overlaid on USGS digital elevation models (DEMs). The water depths have a 4x vertical exaggeration while the land areas have a 2x vertical exaggeration.

  8. Sand sources and transport pathways for the San Francisco Bay coastal system, based on X-ray diffraction mineralogy

    Science.gov (United States)

    Hein, James R.; Mizell, Kira; Barnard, Patrick L.; Barnard, P.L.; Jaffee, B.E.; Schoellhamer, D.H.

    2013-01-01

    The mineralogical compositions of 119 samples collected from throughout the San Francisco Bay coastal system, including bayfloor and seafloor, area beaches, cliff outcrops, and major drainages, were determined using X-ray diffraction (XRD). Comparison of the mineral concentrations and application of statistical cluster analysis of XRD spectra allowed for the determination of provenances and transport pathways. The use of XRD mineral identifications provides semi-quantitative compositions needed for comparisons of beach and offshore sands with potential cliff and river sources, but the innovative cluster analysis of XRD diffraction spectra provides a unique visualization of how groups of samples within the San Francisco Bay coastal system are related so that sand-sized sediment transport pathways can be inferred. The main vector for sediment transport as defined by the XRD analysis is from San Francisco Bay to the outer coast, where the sand then accumulates on the ebb tidal delta and also moves alongshore. This mineralogical link defines a critical pathway because large volumes of sediment have been removed from the Bay over the last century via channel dredging, aggregate mining, and borrow pit mining, with comparable volumes of erosion from the ebb tidal delta over the same period, in addition to high rates of shoreline retreat along the adjacent, open-coast beaches. Therefore, while previously only a temporal relationship was established, the transport pathway defined by mineralogical and geochemical tracers support the link between anthropogenic activities in the Bay and widespread erosion outside the Bay. The XRD results also establish the regional and local importance of sediment derived from cliff erosion, as well as both proximal and distal fluvial sources. This research is an important contribution to a broader provenance study aimed at identifying the driving forces for widespread geomorphic change in a heavily urbanized coastal-estuarine system.

  9. Hydrodynamics and water quality models applied to Sepetiba Bay

    Science.gov (United States)

    Cunha, Cynara de L. da N.; Rosman, Paulo C. C.; Ferreira, Aldo Pacheco; Carlos do Nascimento Monteiro, Teófilo

    2006-10-01

    A coupled hydrodynamic and water quality model is used to simulate the pollution in Sepetiba Bay due to sewage effluent. Sepetiba Bay has a complicated geometry and bottom topography, and is located on the Brazilian coast near Rio de Janeiro. In the simulation, the dissolved oxygen (DO) concentration and biochemical oxygen demand (BOD) are used as indicators for the presence of organic matter in the body of water, and as parameters for evaluating the environmental pollution of the eastern part of Sepetiba Bay. Effluent sources in the model are taken from DO and BOD field measurements. The simulation results are consistent with field observations and demonstrate that the model has been correctly calibrated. The model is suitable for evaluating the environmental impact of sewage effluent on Sepetiba Bay from river inflows, assessing the feasibility of different treatment schemes, and developing specific monitoring activities. This approach has general applicability for environmental assessment of complicated coastal bays.

  10. Study on bayes discriminant analysis of EEG data.

    Science.gov (United States)

    Shi, Yuan; He, DanDan; Qin, Fang

    2014-01-01

    In this paper, we have done Bayes Discriminant analysis to EEG data of experiment objects which are recorded impersonally come up with a relatively accurate method used in feature extraction and classification decisions. In accordance with the strength of α wave, the head electrodes are divided into four species. In use of part of 21 electrodes EEG data of 63 people, we have done Bayes Discriminant analysis to EEG data of six objects. Results In use of part of EEG data of 63 people, we have done Bayes Discriminant analysis, the electrode classification accuracy rates is 64.4%. Bayes Discriminant has higher prediction accuracy, EEG features (mainly αwave) extract more accurate. Bayes Discriminant would be better applied to the feature extraction and classification decisions of EEG data.

  11. Master Agreement Between Bay de Noc Community College Governing Board and Bay de Noc Community College Faculty Association.

    Science.gov (United States)

    Bay de Noc Community Coll., Escanaba, MI.

    This agreement between the Bay de Noc Community College Governing Board and the Bay de Noc Community College Faculty Association covers the period from 1973-75. Contents cover recognition, rights, and guarantees; faculty, personnel, and division procedures; appointments, promotions, reductions, and related matters; leaves and absences; grievance…

  12. A Comparative Study of Bayes Net, Naive Bayes and Averaged One-Dependence Estimators for Osteoporosis Analysis.

    Science.gov (United States)

    Waleska Simões, Priscyla; Mazzuchello, Leandro Luiz; Toniazzo de Abreu, Larissa Letieli; Garcia, Diego; dos Passos, Maitê Gabriel; Venson, Ramon; Bisognin Ceretta, Luciane; Veiga Silva, Ana Carolina; da Rosa, Maria Inês; Martins, Paulo João

    2015-01-01

    This paper presents an evaluation of the accuracy of the Bayesian classifiers: Bayes Net, Naive Bayes and Averaged One-Dependence Estimator, to support diagnoses of osteopenia and osteoporosis. All classifiers showed good results, thus, given data, it is possible to produce a reasonably accurate estimate of the diagnosis.

  13. Using Remote Sensing Data to Evaluate Habitat Loss in the Mobile, Galveston, and Tampa Bay Watersheds

    Science.gov (United States)

    Steffen, Morgan; Estes, Maurice G.; Al-Hamdan, Mohammad

    2010-01-01

    The Gulf of Mexico has experienced dramatic wetland habitat area losses over the last two centuries. These losses not only damage species diversity, but contribute to water quality, flood control, and aspects of the Gulf coast economy. Overall wetland losses since the 1950s were examined using land cover/land use (LCLU) change analysis in three Gulf coast watershed regions: Mobile Bay, Galveston Bay, and Tampa Bay. Two primary causes of this loss, LCLU change and climate change, were then assessed using LCLU maps, U.S. census population data, and available current and historical climate data from NOAA. Sea level rise, precipitation, and temperature effects were addressed, with emphasis on analysis of the effects of sea level rise on salt marsh degradation. Ecological impacts of wetland loss, including fishery depletion, eutrophication, and hypoxia were addressed using existing literature and data available from NOAA. These ecological consequences in turn have had an affect on the Gulf coast economy, which was analyzed using fishery data and addressing public health impacts of changes in the environment caused by wetland habitat loss. While recent federal and state efforts to reduce wetland habitat loss have been relatively successful, this study implies a need for more aggressive action in the Gulf coast area, as the effects of wetland loss reach far beyond individual wetland systems themselves to the Gulf of Mexico as a whole.

  14. Chemical characteristics, deposition fluxes and source apportionment of precipitation components in the Jiaozhou Bay, North China

    Science.gov (United States)

    Xing, Jianwei; Song, Jinming; Yuan, Huamao; Li, Xuegang; Li, Ning; Duan, Liqin; Qu, Baoxiao; Wang, Qidong; Kang, Xuming

    2017-07-01

    To systematically illustrate the chemical characteristics, deposition fluxes and potential sources of the major components in precipitation, 49 rainwater and snow water samples were collected in the Jiaozhou Bay from June 2015 to May 2016. We determined the pH, electric conductivity (EC) and the concentrations of main ions (Na+, K+, Ca2 +, Mg2 +, NH4+, SO42 -, NO3-, Cl- and F-) as well as analyzed their source contributions and atmospheric transport. The results showed that the precipitation samples were severely acidified with an annual volume-weighted mean (VWM) pH of 4.77. The frequency of acid precipitation (pH components in the precipitation. Non-sea-salt SO42 - and NO3- were the primary acid components while NH4+ and non-sea-salt Ca2 + were the dominating neutralizing constituents. The comparatively lower rainwater concentration of Ca2 + in the Jiaozhou Bay than that in other regions in Northern China likely to be a cause for the strong acidity of precipitation. Based on the combined enrichment factor and correlation analysis, the integrated contributions of sea-salt, crustal and anthropogenic sources to the total ions of precipitation were estimated to be 28.7%, 14.5% and 56.8%, respectively. However, the marine source fraction of SO42 - may be underestimated as the contribution from marine phytoplankton was neglected. Therefore, the precipitation components in the Jiaozhou Bay present complex chemical characteristics under the combined effects of natural changes and anthropogenic activities.

  15. Influenza A virus: sampling of the unique shorebird habitat at Delaware Bay, USA.

    Science.gov (United States)

    Poulson, Rebecca L; Luttrell, Page M; Slusher, Morgan J; Wilcox, Benjamin R; Niles, Lawrence J; Dey, Amanda D; Berghaus, Roy D; Krauss, Scott; Webster, Robert G; Stallknecht, David E

    2017-11-01

    Delaware (DE) Bay, in the northeastern USA, has long been recognized as a hotspot for avian influenza A virus (IAV); every spring, this coastal region serves as a brief stopover site for thousands of long-distance migrating shorebirds, en route to breeding grounds in the Arctic. During these stopovers, IAV has been consistently recovered from ruddy turnstones (Arenaria interpres) that are likely to become infected as they feed by probing sand and cobble in search of food. In May 2010-2012, we successfully isolated 19 IAV from environmental samples (sand, n = 18; horseshoe crab eggs, n = 1) obtained from DE Bay sites. Two of these viruses were subjected to laboratory conditions similar to those in the DE Bay spring-time environment, and remained infectious for 7 days. Here, through the recovery of IAV from environmental samples, temperature monitoring at and below the sand surface and simulated laboratory trials, we provide evidence that the beach environment may enable localized transmission and short-term maintenance of IAV in this unique ecosystem.

  16. Ecological Forecasting in Chesapeake Bay: Using a Mechanistic-Empirical Modelling Approach

    Energy Technology Data Exchange (ETDEWEB)

    Brown, C. W.; Hood, Raleigh R.; Long, Wen; Jacobs, John M.; Ramers, D. L.; Wazniak, C.; Wiggert, J. D.; Wood, R.; Xu, J.

    2013-09-01

    The Chesapeake Bay Ecological Prediction System (CBEPS) automatically generates daily nowcasts and three-day forecasts of several environmental variables, such as sea-surface temperature and salinity, the concentrations of chlorophyll, nitrate, and dissolved oxygen, and the likelihood of encountering several noxious species, including harmful algal blooms and water-borne pathogens, for the purpose of monitoring the Bay's ecosystem. While the physical and biogeochemical variables are forecast mechanistically using the Regional Ocean Modeling System configured for the Chesapeake Bay, the species predictions are generated using a novel mechanistic empirical approach, whereby real-time output from the coupled physical biogeochemical model drives multivariate empirical habitat models of the target species. The predictions, in the form of digital images, are available via the World Wide Web to interested groups to guide recreational, management, and research activities. Though full validation of the integrated forecasts for all species is still a work in progress, we argue that the mechanistic–empirical approach can be used to generate a wide variety of short-term ecological forecasts, and that it can be applied in any marine system where sufficient data exist to develop empirical habitat models. This paper provides an overview of this system, its predictions, and the approach taken.

  17. Relative Sea Level Trends Along the Coast of the Bay of Bengal

    Science.gov (United States)

    Becker, M.; Calmant, S.; Papa, F.; Delebecque, C.; Islam, A. S.; Shum, C. K.

    2016-12-01

    In the coastal belt of the Bay of Bengal, the sea level rise is one of a major threat, linked to climate change, which drastically affects the livelihoods of millions of people. A comprehensive understanding of sea level trends and its variability in this region is therefore crucial and should help to anticipate the impacts of climate change and implement adaptation strategies. This region is bordered mostly by Bangladesh, India, Malaysia, Myanmar, and Thailand. Here, we revisit the sea level changes in the Bay of Bengal region from tide gauges and satellite altimetry over the period 1993-2014. The 23 monthly mean tide gauge records, used in this study, are retrieved from PSMSL (15 records) and supplemented with Bangladeshi observations (8 records). We show that, over the satellite altimetry era, the sea level interannual/decadal variability is mainly due to ocean thermal expansion variability driven by IOD/ENSO events and their low frequency modulation. We focus on relative sea level rise at major coastal cities and try to separate the climatic signal (long term trend plus interannual/decadal variability) from local effects, in particular vertical land movements. Results from GPS are analysed where available. When no such data exist, vertical land movements are deduced from the combined use of tide gauge and altimetry data. While the analysis is performed over the whole region, a particular attention is given to the low-lyingBangladesh's coastal area.

  18. GPU MrBayes V3.1: MrBayes on Graphics Processing Units for Protein Sequence Data.

    Science.gov (United States)

    Pang, Shuai; Stones, Rebecca J; Ren, Ming-Ming; Liu, Xiao-Guang; Wang, Gang; Xia, Hong-ju; Wu, Hao-Yang; Liu, Yang; Xie, Qiang

    2015-09-01

    We present a modified GPU (graphics processing unit) version of MrBayes, called ta(MC)(3) (GPU MrBayes V3.1), for Bayesian phylogenetic inference on protein data sets. Our main contributions are 1) utilizing 64-bit variables, thereby enabling ta(MC)(3) to process larger data sets than MrBayes; and 2) to use Kahan summation to improve accuracy, convergence rates, and consequently runtime. Versus the current fastest software, we achieve a speedup of up to around 2.5 (and up to around 90 vs. serial MrBayes), and more on multi-GPU hardware. GPU MrBayes V3.1 is available from http://sourceforge.net/projects/mrbayes-gpu/. © The Author 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  19. Shaded Relief with Height as Color, Manila Bay, Philippines

    Science.gov (United States)

    2002-01-01

    These two images show exactly the same area, Manila Bay and nearby volcanoes on Luzon Island in the Philippines. The image on the left was created using the best global topographic data set previously available, the U.S. Geological Survey's GTOPO30. In contrast, the much more detailed image on the right was generated with data from the Shuttle Radar Topography Mission, which collected enough measurements to map 80 percent of Earth's landmass at this level of precision.The city of Manila is on the eastern shore of Manila Bay at the right edge of the image. The large central plain to the north of the bay, irrigated by the Panpanga and Agno rivers, is the most important agricultural region in the Philippines. The Bataan Peninsula and volcanic Mt. Bataan at lower center along with the small island of Corregidor near the bottom edge became famous when the Allied forces made their last stand there during World War II. Dominating the upper left of the scene is 1,600 meter (5,249 foot) high Mt. Pinatubo, whose violent eruption on June 15, 1991, wrought widespread destruction on Luzon as well as injecting dust and gas into the atmosphere, which lowered global average temperatures for over a year.The image on the right combines two types of Shuttle Radar Topography Mission data. The image brightness corresponds to the strength of the radar signal reflected from the ground, while colors show the elevation measurements. Colors range from blue at the lowest elevations to brown and white at the highest elevations.For some parts of the globe, Shuttle Radar Topography Mission measurements are 30 times more precise than previously available topographical information, according to NASA scientists. Mission data will be a welcome resource for national and local governments, scientists, commercial enterprises, and members of the public alike. The applications are as diverse as earthquake and volcano, flood control, transportation, urban and regional planning, aviation, recreation, and

  20. Sediment sequences and palynology of outer South Bay, Manitoulin Island, Ontario: Connections to Lake Huron paleohydrologic phases and upstream Lake Agassiz events

    Science.gov (United States)

    Lewis, C. F. M.; Anderson, T. W.

    2017-10-01

    South Bay on the southern coast of Manitoulin Island is a fjord-like embayment connected to Lake Huron by a natural narrow gap in the bay's outer sill 6.5-14 m above the lake. A seismic profile, pollen, plant macrofossil, grain size analyses, and other sediment properties of two piston cores from a shallow outer basin of the bay document a 9 m-thick sediment section comprising rhythmically laminated clay under silty clay containing zones with small molluscan shells and marsh detritus. A sandy pebbly layer under soft silty clay mud overlies these sediments. This stratigraphy represents inundation by deep glacial Lake Algonquin followed by the shallowing Post Algonquin series of lakes, and exposure in the early Holocene by 5 Lake Stanley lowstands in the Lake Huron basin separated by 4 Lake Mattawa highstands. Overflow from South Bay in the first lowstand is thought to have eroded the outer sill gap. Marsh environments are inferred to have formed in the bay during subsequent lowstands. The Lake Mattawa highstands are attributed to outburst floods mainly from glacial Lake Agassiz. Palynological evidence of increased spruce occurrence, an apparent regional climate reversal, during the dry pine period is attributed to cold northwest winds from the Lake Superior basin and a lake effect from the Mattawa highstands in the Lake Huron basin. Lake waters transgressed South Bay following the pine period to form the Nipissing shore on Manitoulin Island. Transfer of Lake Huron basin drainage to southern outlets and continued glacioisostatic uplift of the region led to the present configuration of South Bay and Lake Huron.