WorldWideScience

Sample records for bights

  1. Different zooplankton structures in the German Bight

    Science.gov (United States)

    Martens, P.; Brockmann, U.

    1993-06-01

    In August 1982, a net of 48 stations with altogether 208 samples was investigated in the eastern German Bight with respect to temperature, salinity, as well as the amount and species composition of the mesozooplankton (>80 μm). The data were arranged into different structures by means of a cluster analysis. Four different clusters were found: (a) a “Wadden sea water” with few holoplankton organisms but a higher amount of spionid larvae; (b) a “German Bight water” with a maximum occurrence of turbellaria ( Alaurina composita) and medium concentrations of copepods; (c) a mixing area between these two water masses with highest amounts of Oikopleura dioica, Temora longicornis, Acartia sp., mussel larvae and larvae of the spionid worms; (d) a “North Sea water” mass with highest concentrations of Pseudocalanus elongatus, Paracalanus parvus und Oithona similis. The differences in the concentrations of the species mentioned between the four clusters were significant on the 0.1%-level.

  2. Dipole vortices in the Great Australian Bight

    DEFF Research Database (Denmark)

    Cresswell, George R.; Lund-Hansen, Lars C.; Nielsen, Morten Holtegaard

    2015-01-01

    Shipboard measurements from late 2006 made by the Danish Galathea 3 Expedition and satellite sea surface temperature images revealed a chain of cool and warm mushroom' dipole vortices that mixed warm, salty, oxygen-poor waters on and near the continental shelf of the Great Australian Bight (GAB...... denser than the cooler offshore waters. The field of dipoles evolved and distorted, but appeared to drift westwards at 5km day-1 over two weeks, and one new mushroom carried GAB water southwards at 7km day(-1). Other features encountered between Cape Leeuwin and Tasmania included the Leeuwin Current...

  3. Exchange studies in the Kiel Bight

    Energy Technology Data Exchange (ETDEWEB)

    Hubrich, L M; Schott, F

    1975-11-01

    The knowledge of exchange and mixing parameters and their dependence on meteorological and oceanographic factors in coastal waters plays a predominant role in the estimation of the capacity of those areas for waste water and waste heat. On this subject experimental investigations are carried out in the Kiel Bight, part of the Western Baltic. The paper reports about dye mixing experiments, about the development of a combined aircraft-ship measuring method and about experimental results with low wind velocities and low current velocities. On the basis of measured horizontal surface temperature distributions an estimation of the local heat load in the inner Kiel Fjord from the cooling water of a power plant is also given.

  4. Ecosystem responses to biogeochemical fronts in the South Brazil Bight

    Science.gov (United States)

    Brandini, Frederico P.; Tura, Pedro M.; Santos, Pedro P. G. M.

    2018-05-01

    Here we described the general hydrography in the South Brazil Bight (23-28°S) with emphasis on frontal processes and their role in the structure and functioning of the regional shelf ecosystem. One of the key roles of fronts for ecosystem dynamics is the injection of nutrients into the euphotic zone increasing primary production. Frontal systems also affect plankton biodiversity and fisheries. Physical mechanisms behind frontogenesis in this region are similar in the analogous western side of oceanic basins; their magnitude and seasonal dynamics, however, may differ due to peculiarities in shelf morphology, wind field, tidal circulation and continental drainage. Here we provide a reassessment of earlier and recent ecological and hydrographic studies for a better evaluation of the spatial and temporal dynamics of fronts and their regional ecological implications. Albeit in a fragmented manner, we give a more detailed conceptual framework about the ecosystem responses to the complex frontal system in the South Brazil Bight.

  5. Natural radionuclides in waters of the New York bight

    Energy Technology Data Exchange (ETDEWEB)

    Li, Y H; Santschi, P H; Feely, H W [Columbia Univ., Palisades, NY (USA). Lamont-Doherty Geological Observatory; Kaufman, A; Benninger, L K [Yale Univ., New Haven, CT (USA). Dept. of Geology and Geophysics

    1981-10-01

    The half removal time of /sup 228/Th from the surface waters by settling particles, tsub(c), does not change much with season, except in the winter when regenerated /sup 228/Th as well as /sup 210/Pb and /sup 210/Po were transported back to the surface water from the bottom water and/or near-shore sediments. The removal of /sup 228/Th and /sup 210/Pb from the surface waters of New York Bight by phytoplankton-zooplankton-fecal pellet route is not important in the shelf but is important in the slope areas. The removal of /sup 210/Po is almost entirely associated with the phytoplankton-zooplankton-fecal pellet pathway throughout the New York Bight.

  6. Coastal ocean transport patterns in the central Southern California Bight

    Science.gov (United States)

    Noble, M.A.; Rosenberger, K.J.; Hamilton, P.; Xu, J. P.

    2009-01-01

    In the past decade, several large programs that monitor currents and transport patterns for periods from a few months to a few years were conducted by a consortium of university, federal, state, and municipal agencies in the central Southern California Bight, a heavily urbanized section of the coastal ocean off the west coast of the United States encompassing Santa Monica Bay, San Pedro Bay, and the Palos Verdes shelf. These programs were designed in part to determine how alongshelf and cross-shelf currents move sediments, pollutants, and suspended material through the region. Analysis of the data sets showed that the current patterns in this portion of the Bight have distinct changes in frequency and amplitude with location, in part because the topography of the shelf and upper slope varies rapidly over small spatial scales. However, because the mean, subtidal, and tidal-current patterns in any particular location were reasonably stable with time, one could determine a regional pattern for these current fields in the central Southern California Bight even though measurements at the various locations were obtained at different times. In particular, because the mean near-surface flows over the San Pedro and Palos Verdes shelves are divergent, near-surface waters from the upper slope tend to carry suspended material onto the shelf in the northwestern portion of San Pedro Bay. Water and suspended material are also carried off the shelf by the mean and subtidal flow fields in places where the orientation of the shelf break changes abruptly. The barotropic tidal currents in the central Southern California Bight flow primarily alongshore, but they have pronounced amplitude variations over relatively small changes in alongshelf location that are not totally predicted by numerical tidal models. Nonlinear internal tides and internal bores at tidal frequencies are oriented more across the shelf. They do not have a uniform transport direction, since they move fine sediment

  7. Marine Ecosystems Analysis (MESA) Program, New York Bight Surficial Sediment Analyses

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Marine Ecosystems Analysis (MESA) Program, New York Bight Study was funded by NOAA and the Bureau of Land Management (BLM). The Atlas was a historical...

  8. Multibeam Mapping of the South Atlantic Bight: Georgia 2005, a Proposed MPA on the Continental Shelf

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA Fisheries laboratory in Panama City, Florida coordinated an acoustic survey at the new proposed Marine Protected Areas in the South Atlantic Bight area June...

  9. Biological processes in the water column of the South Atlantic bight

    Energy Technology Data Exchange (ETDEWEB)

    Paffenhoefer, G.A.; Yoder, J.A.

    1980-01-31

    Progress is reported on research conducted during 1979 on the biological oceanography of the South Atlantic Bight. The presentation consists of a number of published articles and abstracts of oral presentations. (ACR)

  10. Automated ocean color product validation for the Southern California Bight

    Science.gov (United States)

    Davis, Curtiss O.; Tufillaro, Nicholas; Jones, Burt; Arnone, Robert

    2012-06-01

    Automated match ups allow us to maintain and improve the products of current satellite ocean color sensors (MODIS, MERIS), and new sensors (VIIRS). As part of the VIIRS mission preparation, we have created a web based automated match up tool that provides access to searchable fields for date, site, and products, and creates match-ups between satellite (MODIS, MERIS, VIIRS), and in-situ measurements (HyperPRO and SeaPRISM). The back end of the system is a 'mySQL' database, and the front end is a `php' web portal with pull down menus for searchable fields. Based on selections, graphics are generated showing match-ups and statistics, and ascii files are created for downloads for the matchup data. Examples are shown for matching the satellite data with the data from Platform Eureka SeaPRISM off L.A. Harbor in the Southern California Bight.

  11. River plume patterns and dynamics within the Southern California Bight

    Science.gov (United States)

    Warrick, J.A.; DiGiacomo, P.M.; Weisberg, S.B.; Nezlin, N.P.; Mengel, M.; Jones, B.H.; Ohlmann, J.C.; Washburn, L.; Terrill, E.J.; Farnsworth, K.L.

    2007-01-01

    Stormwater river plumes are important vectors of marine contaminants and pathogens in the Southern California Bight. Here we report the results of a multi-institution investigation of the river plumes across eight major river systems of southern California. We use in situ water samples from multi-day cruises in combination with MODIS satellite remote sensing, buoy meteorological observations, drifters, and HF radar current measurements to evaluate the dispersal patterns and dynamics of the freshwater plumes. River discharge was exceptionally episodic, and the majority of storm discharge occurred in a few hours. The combined plume observing techniques revealed that plumes commonly detach from the coast and turn to the left, which is the opposite direction of Coriolis influence. Although initial offshore velocity of the buoyant plumes was ∼50 cm/s and was influenced by river discharge inertia (i.e., the direct momentum of the river flux) and buoyancy, subsequent advection of the plumes was largely observed in an alongshore direction and dominated by local winds. Due to the multiple day upwelling wind conditions that commonly follow discharge events, plumes were observed to flow from their respective river mouths to down-coast waters at rates of 20–40 km/d. Lastly, we note that suspended-sediment concentration and beam-attenuation were poorly correlated with plume salinity across and within the sampled plumes (mean r2=0.12 and 0.25, respectively), while colored dissolved organic matter (CDOM) fluorescence was well correlated (mean r2=0.56), suggesting that CDOM may serve as a good tracer of the discharged freshwater in subsequent remote sensing and monitoring efforts of plumes.

  12. Phytoplankton Assemblage Patterns in the Southern Mid-Atlantic Bight

    Science.gov (United States)

    Makinen, Carla; Moisan, Tiffany A. (Editor)

    2012-01-01

    As part of the Wallops Coastal Oceans Observing Laboratory (Wa-COOL) Project, we sampled a time-series transect in the southern Mid-Atlantic Bight (MAB) biweekly. Our 2-year time-series data included physical parameters, nutrient concentrations, and chlorophyll a concentrations. A detailed phytoplankton assemblage structure was examined in the second year. During the 2-year study, chlorophyll a concentration (and ocean color satellite imagery) indicated that phytoplankton blooms occurred in January/February during mixing conditions and in early autumn under stratified conditions. The chlorophyll a concentrations ranged from 0.25 microgram 1(exp -1) to 15.49 microgram 1(exp -1) during the 2-year period. We were able to discriminate approximately 116 different species under phase contrast microscopy. Dominant phytoplankton included Skeletonema costatum, Rhizosolenia spp., and Pseudo-nitzschia pungens. In an attempt to determine phytoplankton species competition/succession within the assemblage, we calculated a Shannon Weaver diversity index for our diatom microscopy data. Diatom diversity was greatest during the winter and minimal during the spring. Diatom diversity was also greater at nearshore stations than at offshore stations. Individual genera appeared patchy, with surface and subsurface patches appearing abruptly and persisting for only 1-2 months at a time. The distribution of individual species differed significantly from bulk variables of the assemblage (chlorophyll a ) and total phytoplankton assemblage (cells), which indicates that phytoplankton species may be limited in growth in ways that differ from those of the total assemblage. Our study demonstrated a highly diverse phytoplankton assemblage throughout the year, with opportunistic species dominating during spring and fall in response to seasonal changes in temperature and nutrients in the southern MAB.

  13. A system-level modelling perspective of the KwaZulu-Natal Bight ...

    African Journals Online (AJOL)

    Requirements to take the hydrodynamic, biogeochemical and first ecosystem modelling efforts towards a meaningful predictive capability are discussed. The importance of adopting a system-level view of the bight and its connected systems for realistic exploration of global change scenarios is highlighted. Keywords: ...

  14. Circulation of shelf waters in the KwaZulu-Natal Bight, South Africa ...

    African Journals Online (AJOL)

    Ship-based acoustic Doppler current profiler (S-ADCP) technology, used in survey mode, has enabled nearsynoptic views of the in situ 3-D current field in the KwaZulu-Natal (KZN) Bight to be elucidated for the first time. Data acquired by the research vessels RS Africana and RS Algoa in June 2005, September 2007, March ...

  15. Multibeam Mapping of the South Atlantic Bight: South Carolina 2005, a Proposed MPA on the Continental Shelf

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA Fisheries laboratory in Panama City, Florida coordinated an acoustic survey at the new proposed Marine Protected Areas in the South Atlantic Bight area June...

  16. Significant habitats and habitat complexes of the New York Bight watershed from 1971 to 1996 (NODC Accession 0071981)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This report focuses on the identification and description of essential habitats of key species inhabiting the New York Bight watershed study area. The study area...

  17. LIGHT TRANSMISSION and Other Data from MULTIPLE SHIPS From Great Australian Bight from 19660119 to 19941123 (NODC Accession 9500086)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The secchi disk data were collected from multiple ships in Great Australian Bight between January 1966 and November 1994 by Commonwealth Scientific and Industrial...

  18. Seasonal and spatial variability of major organic contaminants in solution and suspension of the Pomeranian Bight

    OpenAIRE

    Graeve, Martin; Wodarg, Dirk

    2003-01-01

    Studies of hexachlorocyclohexane-isomers (HCHs) and selected triazine herbicides in solution and suspension were carried out in the Pomeranian Bight in 1995. The concentrations of HCHs and triazines were determined by gas-liquid chromatography (GC) or by GC in connection with quadrupole mass spectrometry(GC/MS). Particulate and dissolved material were separated by means of an in-situ filtration/extraction system. The seasonal variability and regional distribution of the various component...

  19. Exploring the Circulation Dynamics of Mississippi Sound and Bight Using the CONCORDE Synthesis Model

    Science.gov (United States)

    Pan, C.; Dinniman, M. S.; Fitzpatrick, P. J.; Lau, Y.; Cambazoglu, M. K.; Parra, S. M.; Hofmann, E. E.; Dzwonkowski, B.; Warner, S. J.; O'Brien, S. J.; Dykstra, S. L.; Wiggert, J. D.

    2017-12-01

    As part of the modeling effort of the GOMRI (Gulf of Mexico Research Initiative)-funded CONCORDE consortium, a high resolution ( 400 m) regional ocean model is implemented for the Mississippi (MS) Sound and Bight. The model is based on the Coupled Ocean Atmosphere Wave Sediment Transport Modeling System (COAWST), with initial and lateral boundary conditions drawn from data assimilative 3-day forecasts of the 1km-resolution Gulf of Mexico Navy Coastal Ocean Model (GOM-NCOM). The model initiates on 01/01/2014 and runs for 3 years. The model results are validated with available remote sensing data and with CONCORDE's moored and ship-based in-situ observations. Results from a three-year simulation (2014-2016) show that ocean circulation and water properties of the MS Sound and Bight are sensitive to meteorological forcing. A low resolution surface forcing, drawn from the North America Regional Reanalysis (NARR), and a high resolution forcing, called CONCORDE Meteorological Analysis (CMA) ) that resolves the diurnal sea breeze, are used to drive the model to examine the sensitivity of the circulation to surface forcing. The model responses to the low resolution NARR forcing and to the high resolution CMA are compared in detail for the CONCORDE Fall and Spring field campaigns when contemporaneous in situ data are available, with a focus on how simulated exchanges between MS Sound and MS Bight are impacted. In most cases, the model shows higher simulation skill when it is driven by CMA. Freshwater plumes of the MS River, MS Sound and Mobile Bay influence the shelf waters of the MS Bight in terms of material budget and dynamics. Drifters and dye experiments near Mobile Bay demonstrate that material exchanges between Mobile Bay and the Sound, and between the Sound and Bight, are sensitive to the wind strength and direction. A model - data comparison targeting the Mobile Bay plume suggests that under both northerly and southerly wind conditions the model is capable of

  20. Determination of shell deposition rates of Arctica islandica from the New York Bight using natural 228Ra and 228Th and bomb-produced 14C

    International Nuclear Information System (INIS)

    Turekian, K.K.; Cochran, J.K.; Nozaki, Y.; Thompson, I.; Jones, D.S.

    1982-01-01

    Shell deposition rates of specimens of Arctica islandica (Mollusca: Bivalvia) from the New York Bight were determined using natural 228 Ra and 228 Th and bomb 14 C. The specimens from deep (>55 m) offshore waters show annual growth banding. A shell obtained from the inner bight at <30-m depth seems to be younger than indicated by band counting

  1. Long-term marine litter monitoring in the remote Great Australian Bight, South Australia.

    Science.gov (United States)

    Edyvane, K S; Dalgetty, A; Hone, P W; Higham, J S; Wace, N M

    2004-06-01

    The Anxious Bay beach litter clearance is the longest running annual survey of ocean-based litter in Australia. It's remoteness from centres of human population and location (with respect to prevailing winds and currents) make it an ideal place for monitoring ocean or ship-based litter in Australia's southern oceans and particularly, the Great Australian Bight. Over the 1991-1999 period, a large but gradual decline in the amount of beach washed litter was recorded (with minor peaks recorded during the 1992 and 1994 surveys). Beach washed litter decreased by approximately 86%, from 344 kg recorded in 1991 (13.2 kg/km) to 49 kg in 1999 (i.e. 1.9 kg/km), reaching a maximum of 390 kg in 1992 (or 15 kg/km of beach). However, a sharp increase in litter was recorded in 2000 (i.e. 252 kg or 9.7 kg/km). This increase in litter yield in 2000 is probably due to stronger than average onshore surface flow (or Ekman Transport) in the western Eyre Peninsula and Bight region. Prior to the survey in 2000, the results appeared to indicate that ocean litter on Anxious Bay beach was beginning to level out at around 50-70 kg/year (i.e. 2-3 kg/km). As the beach surveys involve the assumption that the beach is completely cleared of litter, this may represent a baseline level for ocean-based litter in the region. The yields and type of litter collected from the annual survey indicates that the majority of litter washed ashore originates from commercial fishing activities within the Great Australian Bight. Most of the fishing-related litter was directly sourced to the Southern Rock Lobster Fishery (i.e. bait buckets, baskets, pots), the Great Australian Bight Trawl Fishery (i.e. codends, trawl nets) and the Southern Shark Fishery (i.e. monofilament gillnets and longlines). Between 1994 and 1999, large reductions were observed in the amount of bait straps (77% reduction), lobster bait baskets/buckets (86% reduction), nets/ropes (62% reduction) and floats/buoys (83% reduction). Significantly

  2. Particulate Matter Resuspension in Mississippi Bight Evaluated with CONCORDE's Synthesis Model

    Science.gov (United States)

    O'Brien, S. J.; Quas, L. M.; Miles, T. N.; Pan, C.; Cambazoglu, M. K.; Soto Ramos, I. M.; Greer, A. T.; Church, I.; Wiggert, J. D.

    2017-12-01

    The CONsortium for oil spill exposure pathways in COastal River-Dominated Ecosystems (CONCORDE) was established to investigate the complex fine-scale biological, chemical and physical interactions in a marine system controlled by pulsed-river plume dynamics. During CONCORDE's spring 2016 field campaign, the In Situ Ichthyoplankton Imaging System (ISIIS) on the R/V Point Sur and the Scanfish on the R/V Pelican comprehensively characterized the physical and biological structure in the region. Increased suspended particulate matter was observed by the ISIIS, with concentrations at depth sufficient to completely occlude the in situ images of planktonic organisms. Data was also collected on the continental shelf during the spring cruise by the RU31 glider in the proximity of the Mississippi River Delta, east of the ISIIS / Scanfish transects. Backscatter and salinity observed by the Scanfish and glider showed elevated suspended particulate matter and increased salinity, suggesting a linkage to shoreward advection from the continental shelf of oceanic waters that are sufficiently energetic to drive sediment resuspension. As part of the CONCORDE research effort, a four-dimensional biogeochemical/lower trophic level synthesis model for Mississippi Sound and Bight has been developed, based on the Coupled Ocean-Atmosphere-Wave-Sediment Transport (COAWST) Modeling System. This study utilizes CONCORDE's synthesis model to investigate the physical forcing mechanisms affecting the increased suspended particulate matter concentration observed in the Mississippi Bight during spring 2016, and advection pathways between estuarine and shelf waters in the northern Gulf of Mexico. The results show that episodic, advection-driven resuspension is a critical aspect controlling suspended sediment distributions in Mississippi Bight, which has implications for observed spatio-temporal patterns of planktonic species.

  3. Iceland Scotland Overflow Water flow through the Bight Fracture Zone in June-July 2015

    Science.gov (United States)

    Mercier, Herle; Petit, Tillys; Thierry, Virginie

    2017-04-01

    ISOW (Iceland Scotland Overflow Water) is the densest water in the northern Iceland Basin and a main constituent of the lower limb of the meridional overturning circulation (MOC). ISOW is the product of mixing of dense water originating from the Nordic Seas with Atlantic Water and Labrador Sea Water during its crossing of the Iceland-Faroe-Scotland Ridge and downstream acceleration. In the northern Iceland Basin, ISOW is characterized by potential density σ0 > 27.8 and salinity > 34.94. Downstream of the Iceland-Scotland Ridge, ISOW flows southwestward in a Deep Western Boundary Current along the eastern flank of the Reykjanes Ridge. Models and float trajectories previously suggested that part of the ISOW flow could cross the Reykjanes Ridge through the Bight Fracture Zone. However, no direct observations of the ISOW flow through the Bight Fracture Zone are available that would allow us to quantify its transport and water mass transformation. This lack of direct observations also prevents understanding the dynamics of the throughflow. In this study, we analyzed a set of CTDO2 and LADCP stations acquired in June-July 2015 during the Reykjanes Ridge Experiment cruise and provide new insights on the ISOW flow through the Bight Fracture Zone. The evolution of the properties as well as the velocity measurements confirm an ISOW flow from the Iceland Basin to the Irminger Sea. A main constrain to the throughflow is the presence of two sills of about 2150 m depth and two narrows. With potential densities between 27.8-27.87 kg m-3 and near bottom potential temperature of 3.02°C and salinity of 34.98, only the lightest variety of ISOW is found at the entrance of the BFZ east of the sills. In the central part of the Bight Fracture Zone, the evolution of ISOW is characterized by a decrease of 0.015 kg m-3 in the near bottom density, ascribed to the blocking of the densest ISOW variety by the sills and/or diapycnal mixing. To the West, at the exit of the BFZ, ISOW overlays

  4. Seasonal dynamics and functioning of the Sylt-Rømø Bight, northern Wadden Sea

    Science.gov (United States)

    de la Vega, Camille; Horn, Sabine; Baird, Dan; Hines, David; Borrett, Stuart; Jensen, Lasse Fast; Schwemmer, Philipp; Asmus, Ragnhild; Siebert, Ursula; Asmus, Harald

    2018-04-01

    The Wadden Sea undergoes large seasonal changes in species abundance and biomass comprising its complex food web. This study examined four carbon food web models of the Sylt-Rømø Bight, one for each season. Each flow model consisted of 66 compartments depicting the respective biomass and energy budget of each ecosystem component and the flows between them. Ecological network analysis (ENA), a set of algorithms to evaluate the functioning of ecological networks, was used to assess the seasonal variability in the system properties of the Sylt-Rømø Bight food webs. We used an uncertainty analysis to quantitatively evaluate the significance of inter-seasonal differences. Clear seasonal variation was observed in most of the whole system indicators such as the flow diversity, the effective link density and the relative redundancy which varied by 12.8%, 17.3% and 10.3% respectively between the highest in summer and the lowest during fall and winter, whereas the relevant ascendency ratio was the highest in winter during the least active months. Other indices such as the average mutual information index, which fluctuated between 1.73 in fall and 1.79 in spring, showed no significant variation between seasons. Results from ENA have great potential for ecosystem management, as it provides a holistic assessment of the functioning of ecosystems.

  5. Some Hydroids (Cnidaria, Hydrozoa) from the Great Australian Bight in the collection of the South Australian Museum.

    Science.gov (United States)

    Watson, Jeanette E

    2018-04-16

    This report adds to knowledge of the shelf hydroid fauna of the Great Australian Bight. Hydroids were collected by the South Australian Museum and Department of Primary Industries of South Australia (PIRSA). Well known species are annotated, poorly known species are redescribed and four new species are described.

  6. Catchment-coastal zone interaction based upon scenario and model analysis: Elbe and the German Bight case study

    NARCIS (Netherlands)

    Hofmann, J.; Behrendt, H.; Gilbert, A.J.; Janssen, R.; Kannen, A.; Kappenberg, J.W.; Lenhart, H.; Lise, W.; Nunneri, C.; Windhorst, W.

    2005-01-01

    This paper presents a holistic strategy on the interaction of activities in the Elbe river basin and their effects on eutrophication in the coastal waters of the German Bight. This catchment-coastal zone interaction is the main target of the EUROCAT (EUROpean CATchments, catchment changes and their

  7. NOAA TIFF Image - 30m Backscatter, South Atlantic Bight - Deep Coral Priority Areas - Navy Pathfinder - (2003), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the bathymetry of several deep coral priority areas off the South Atlantic Bight,...

  8. NOAA TIFF Image - 10m Bathymetric Rugosity, South Atlantic Bight - Deep Coral Priority Areas - NOAA Ship Nancy Foster - (2007), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 10x10 meter cell size representing the rugosity of several deep coral priority areas off the South Atlantic Bight,...

  9. NOAA TIFF Image - 10m Multibeam Bathymetry, South Atlantic Bight - Deep Coral Priority Areas - NOAA Ship Nancy Foster - (2010), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 10x10 meter cell size representing the bathymetry of several deep coral priority areas off the South Atlantic Bight,...

  10. NOAA TIFF Image - 30m Multibeam Bathymetry, South Atlantic Bight - Deep Coral Priority Areas - Navy Pathfinder - (2003), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the bathymetry of several deep coral priority areas off the South Atlantic Bight,...

  11. NOAA TIFF Image - 10m Multibeam Bathymetry, South Atlantic Bight - Deep Coral Priority Areas - NOAA Ship Nancy Foster - (2007), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 10x10 meter cell size representing the bathymetry of several deep coral priority areas off the South Atlantic Bight,...

  12. Data collected in the Southern California Bight in order to understand the coastal waters ecological systems, 1977 - 1999 (NODC Accession 0001162)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Chemistry, fish species, atmospheric pollutants, and temperature profile were collected using CTD casts and other collection methods in the Southern California Bight...

  13. NOAA TIFF Image - 30m Rugosity, South Atlantic Bight - Deep Coral Priority Areas - Navy Pathfinder - (2003), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the bathymetry of several deep coral priority areas off the South Atlantic Bight,...

  14. NOAA TIFF Image - 10m Multibeam Bathymetry, South Atlantic Bight - Deep Coral Priority Areas - NOAA Ship Nancy Foster - (2009), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 10x10 meter cell size representing the bathymetry of several deep coral priority areas off the South Atlantic Bight,...

  15. Monitoring shipping emissions in the German Bight using MAX-DOAS measurements

    Science.gov (United States)

    Seyler, André; Wittrock, Folkard; Kattner, Lisa; Mathieu-Üffing, Barbara; Peters, Enno; Richter, Andreas; Schmolke, Stefan; Burrows, John P.

    2017-04-01

    Shipping is generally the most energy efficient transportation mode, but, at the same time, it accounts for four fifths of the worldwide total merchandise trade volume. As a result, shipping contributes a significant part to the emissions from the transportation sector. The majority of shipping emissions occurs within 400 km of land, impacting on air pollution in coastal areas and harbor towns. The North Sea has one of the highest ship densities in the world and the vast majority of ships heading for the port of Hamburg sail through the German Bight and into the river Elbe. A three-year time series of ground-based MAX-DOAS measurements of NO2 and SO2 on the island Neuwerk in the German Bight has been analyzed for contributions from shipping emissions. Measurements of individual ship plumes as well as of background pollution are possible from this location, which is 6-7 kilometers away from the main shipping lane towards the harbor of Hamburg. More than 2000 individual ship plumes have been identified in the data and analyzed for the emission ratio of SO2 to NO2, yielding an average ratio of 0.3 for the years 2013/2014. Contributions of ships and land-based sources to air pollution levels in the German Bight have been estimated, showing that despite the vicinity to the shipping lane, the contribution of shipping sources to air pollution is only about 40%. Since January 2015, much lower fuel sulfur content limits of 0.1% (before: 1.0%) apply in the North and Baltic Sea Emission Control Area (ECA). Comparing MAX-DOAS measurements from 2015/2016 (new regulation) to 2013/2014 (old regulation), a large reduction in SO2/NO2 ratios in shipping emissions and a significant reduction (by a factor of eight) in ambient coastal SO2 levels have been observed. In addition to that, selected shipping emission measurements from other measurement sites and campaigns are presented. This study is part of the project MeSMarT (Measurements of Shipping emissions in the Marine Troposphere

  16. Infestation of oysters and mussels by mytilicolid copepods: differences between natural coastal habitats and two offshore cultivation sites in the German Bight

    OpenAIRE

    Pogoda, Bernadette; Jungblut, Simon; Buck, Bela H.; Hagen, Wilhelm

    2012-01-01

    The aim of this study was to determine the macro-parasitic infestation level of oysters from the southern German Bight focussing on copepods of the genus Mytilicola. Crassostrea gigas, Ostrea edulis and Mytilus edulis were collected at five locations: three nearshore sites in the eastern Wadden Sea and two offshore cultivation sites in the German Bight. To reveal seasonal variations one sampling site was investigated in winter and summer. At the nearshore sites, Mytilicola orientalis was regu...

  17. Occurrence and distribution of triclosan in the German Bight (North Sea)

    Energy Technology Data Exchange (ETDEWEB)

    Zhiyong, Xie [GKSS Research Centre Geesthacht, Institute for Coastal Research, Max-Planck Strasse 1, D-21502 Geesthacht (Germany); Institute of Ecology and Environmental Chemistry, University of Lueneburg, Scharnhorststrasse 1, D-21335 Lueneburg (Germany)], E-mail: zhiyong.xie@gkss.de; Ebinghaus, Ralf; Floeser, Goetz; Caba, Armando [GKSS Research Centre Geesthacht, Institute for Coastal Research, Max-Planck Strasse 1, D-21502 Geesthacht (Germany); Ruck, Wolfgang [Institute of Ecology and Environmental Chemistry, University of Lueneburg, Scharnhorststrasse 1, D-21335 Lueneburg (Germany)

    2008-12-15

    The potential of triclosan (TCS) acting as an endocrine disruptor has led to growing concern about the presence of TCS in the environment. In this study, seawater samples were collected from the German Bight during sampling campaigns conducted with the German research ships Gauss and Ludwig Prandtl. TCS was determined both in the dissolved phase and in the suspended particulate matters with concentrations ranging 0.8-6870 pg L{sup -1} and <1-95 pg L{sup -1}, respectively. High concentrations of TCS were present in the estuaries of the Elbe and the Weser, indicating significant input of TCS by the river discharge. The correlation coefficient (R{sup 2}) between the dissolved concentration and salinity was 0.79 for the data obtained from the Gauss cruise, showing an obvious declining trend from the coast to the open sea. - Investigation with coastal survey reveals distribution of triclosan in marine waters.

  18. Occurrence and distribution of triclosan in the German Bight (North Sea)

    International Nuclear Information System (INIS)

    Xie Zhiyong; Ebinghaus, Ralf; Floeser, Goetz; Caba, Armando; Ruck, Wolfgang

    2008-01-01

    The potential of triclosan (TCS) acting as an endocrine disruptor has led to growing concern about the presence of TCS in the environment. In this study, seawater samples were collected from the German Bight during sampling campaigns conducted with the German research ships Gauss and Ludwig Prandtl. TCS was determined both in the dissolved phase and in the suspended particulate matters with concentrations ranging 0.8-6870 pg L -1 and -1 , respectively. High concentrations of TCS were present in the estuaries of the Elbe and the Weser, indicating significant input of TCS by the river discharge. The correlation coefficient (R 2 ) between the dissolved concentration and salinity was 0.79 for the data obtained from the Gauss cruise, showing an obvious declining trend from the coast to the open sea. - Investigation with coastal survey reveals distribution of triclosan in marine waters

  19. Cephalopods and cetaceans as indicators of offshore bioavailability of cadmium off Central South Brazil Bight

    Energy Technology Data Exchange (ETDEWEB)

    Dorneles, Paulo Renato [Laboratorio de Radioisotopos Eduardo Penna Franca, Instituto de Biofisica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro (UFRJ), 21941-900 Rio de Janeiro, RJ (Brazil) and Laboratorio de Mamiferos Aquaticos, Dept. Oceanografia, UERJ, 20550-013 Rio de Janeiro, RJ (Brazil)]. E-mail: dorneles@biof.ufrj.br; Lailson-Brito, Jose [Laboratorio de Radioisotopos Eduardo Penna Franca, Instituto de Biofisica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro (UFRJ), 21941-900 Rio de Janeiro, RJ (Brazil) and Laboratorio de Mamiferos Aquaticos, Dept. Oceanografia, UERJ, 20550-013 Rio de Janeiro, RJ (Brazil)]. E-mail: lailson@uerj.br; Aguiar dos Santos, Roberta [Centro de Pesquisa e Gestao de Recursos Pesqueiros do Litoral Sudeste e Sul, IBAMA, 88301-700 Itajai, SC (Brazil)]. E-mail: gibteuthis@yahoo.com.br; Silva da Costa, Paulo Alberto [Laboratorio de Dinamica de Populacoes Marinhas, UNIRIO, 22290-240 Rio de Janeiro, RJ (Brazil)]. E-mail: pauloascosta@uol.com.br; Malm, Olaf [Laboratorio de Radioisotopos Eduardo Penna Franca, Instituto de Biofisica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro (UFRJ), 21941-900 Rio de Janeiro, RJ (Brazil)]. E-mail: olaf@biof.ufrj.br; Azevedo, Alexandre Freitas [Laboratorio de Mamiferos Aquaticos, Dept. Oceanografia, UERJ, 20550-013 Rio de Janeiro, RJ (Brazil)]. E-mail: azevedo.alex@uol.com.br; Machado Torres, Joao Paulo [Laboratorio de Radioisotopos Eduardo Penna Franca, Instituto de Biofisica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro (UFRJ), 21941-900 Rio de Janeiro, RJ (Brazil)]. E-mail: jptorres@biof.ufrj.br

    2007-07-15

    Regarding Brazilian coast, industrial and urban developments are concentrated along Central South Brazil Bight. Samples from inshore and offshore species from the concerned area were analyzed, comprising 24 cetaceans (9 species) and 32 squids (2 species). Cadmium was determined by GFAAS and our results were in agreement with certified values (DOLT-2, NRCC). Mean cadmium concentration (in {mu}g/g, wet weight) observed in the digestive gland of sexually mature Argentine short-finned squids (Illex argentinus) was 1002.9. To our knowledge this is the highest cadmium level ever reported for a cephalopod. Concerning cetaceans, our results include one of the highest renal cadmium concentrations described for striped dolphins (71.29 {mu}g/g, wet weight). Anthropogenic action, upwelling and cannibalism of Argentine short-finned squid on the studied area are possible reasons for such remarkable cadmium concentrations. - Cd levels in ommastrephid squids from Brazil are the highest ever reported for cephalopods.

  20. Cephalopods and cetaceans as indicators of offshore bioavailability of cadmium off Central South Brazil Bight

    International Nuclear Information System (INIS)

    Dorneles, Paulo Renato; Lailson-Brito, Jose; Aguiar dos Santos, Roberta; Silva da Costa, Paulo Alberto; Malm, Olaf; Azevedo, Alexandre Freitas; Machado Torres, Joao Paulo

    2007-01-01

    Regarding Brazilian coast, industrial and urban developments are concentrated along Central South Brazil Bight. Samples from inshore and offshore species from the concerned area were analyzed, comprising 24 cetaceans (9 species) and 32 squids (2 species). Cadmium was determined by GFAAS and our results were in agreement with certified values (DOLT-2, NRCC). Mean cadmium concentration (in μg/g, wet weight) observed in the digestive gland of sexually mature Argentine short-finned squids (Illex argentinus) was 1002.9. To our knowledge this is the highest cadmium level ever reported for a cephalopod. Concerning cetaceans, our results include one of the highest renal cadmium concentrations described for striped dolphins (71.29 μg/g, wet weight). Anthropogenic action, upwelling and cannibalism of Argentine short-finned squid on the studied area are possible reasons for such remarkable cadmium concentrations. - Cd levels in ommastrephid squids from Brazil are the highest ever reported for cephalopods

  1. Ocean-atmosphere pollutant circulation processes: The Heligoland Bight ecosystem (PRISMA). 2. interim report (1991)

    International Nuclear Information System (INIS)

    1992-04-01

    The PRISMA BMFT project is an important stage on the way to a comprehensive knowledge of the impacts of pollutants on the North Sea/Heligoland Bight ecosystem. The overall project is dedicated to the development, verification and application of a complex shelf-sea model which provides qualitative and quantitative data about the causal interactions between the basic atmospheric conditions, the hydrodynamics and thermodynamics of the water, the chemical reactons in the air, in the water and the sediments, and the activity of organisms. The model comprises a compact set of formulae, process formulations, initial and marginal conditions and empirical parameters which serves to describe the origin, transport, reactions and final deposition of pollutants in the North Sea, helps to analyze and elucidate the present condition of the ecosystem and its spatial and temporal variability, and provides forecasts in accordance with the changing natural and anthropogenic environmental conditions. (orig.) [de

  2. Brazilian sardine (Sardinella brasiliensis spawning in the southeast Brazilian Bight over the period 1976-1993

    Directory of Open Access Journals (Sweden)

    Yasunobu Matsuura

    1998-01-01

    Full Text Available Based on sampling over the period 1976-1993 in the southeast Brazilian Bight, the distribution of spawning of the Brazilian sardine (Sardinella brasi/iensis is described in relation to environmental conditions. The area of intense spawning occurs in the southern part of the bight where coastal upwelling was less /Tequent. Spawning intensity showed high interannllal variation and the egg abundance in the survey area ranged /Tom 99 billion eggs in the January 1988 cruise to 4669 billion eggs in the January 1981 cruise. Peak spawning takes place one hour after midnight and eggs hatch . out within 19 hours with a water temperature of 24 °e.Baseado nos dados coletados durante nove cruzeiros oceanográficos realizados na região sudeste, as áreas de desova da sardinha-verdadeira (Sardinella brasiliensis foram apresentadas c discutidas em relação às condições oceanográficas. As áreas de desova intensiva foram localizadas na parte sul da área de investigação, onde a ressurgência costeira foi menos freqüente. A intensidade de desova demonstrou uma variação anual relativamente grande. A produção total de ovos da sardinha- ­verdadeira variou de 99 bilhões de ovos durante o cruzeiro de janeiro de 1988 para 4669 bilhões de ovos em janeiro de 1981. O pico de desova ocorre na camada de mistura de superfície uma hora após a meia noite e os ovos eclodem em 19 horas com a temperatura de água 24 °e.

  3. Impacts of stormwater runoff in the Southern California Bight: Relationships among plume constituents

    Science.gov (United States)

    Reifel, K.M.; Johnson, S.C.; DiGiacomo, P.M.; Mengel, M.J.; Nezlin, N.P.; Warrick, J.A.; Jones, B.H.

    2009-01-01

    The effects from two winter rain storms on the coastal ocean of the Southern California Bight were examined as part of the Bight '03 program during February 2004 and February-March 2005. The impacts of stormwater from fecal indicator bacteria, water column toxicity, and nutrients were evaluated for five major river discharges: the Santa Clara River, Ballona Creek, the San Pedro Shelf (including the Los Angeles, San Gabriel, and Santa Ana Rivers), the San Diego River, and the Tijuana River. Exceedances of bacterial standards were observed in most of the systems. However, the areas of impact were generally spatially limited, and contaminant concentrations decreased below California Ocean Plan standards typically within 2-3 days. The largest bacterial concentrations occurred in the Tijuana River system where exceedances of fecal indicator bacteria were noted well away from the river mouth. Maximum nitrate concentrations (~40 ??M) occurred in the San Pedro Shelf region near the mouth of the Los Angeles River. Based on the results of general linear models, individual sources of stormwater differ in both nutrient concentrations and the concentration and composition of fecal indicator bacteria. While nutrients appeared to decrease in plume waters due to simple mixing and dilution, the concentration of fecal indicator bacteria in plumes depends on more than loading and dilution rates. The relationships between contaminants (nutrients and fecal indicator bacteria) and plume indicators (salinity and total suspended solids) were not strong indicating the presence of other potentially important sources and/or sinks of both nutrients and fecal indicator bacteria. California Ocean Plan standards were often exceeded in waters containing greater than 10% stormwater (variables can be used as proxies to provide at least a qualitative, if not quantitative, evaluation of the distribution of the dissolved, as well as the particulate, components of stormwater plumes. In this context

  4. Assessment of the Water Levels and Currents at the Mississippi Bight During Hurricane Katrina.

    Science.gov (United States)

    Nwankwo, U. C.; Howden, S. D.; Dodd, D.; Wells, D. E.

    2017-12-01

    In an effort to extend the length of GPS baselines further offshore, the Hydrographic Science Research Center at the University of Southern Mississippi deployed a buoy which had a survey grade GPS receiver, an ADPC and a motion sensor unit in the Mississippi Bight in late 2004. The GPS data were initially processed using the Post Processed Kinematic technique with data from a nearby GPS base station on Horn Island. This processing technique discontinued when the storm (Hurricane Katrina) destroyed the base station in late August of 2005. However, since then a stand-alone positioning technique termed Precise Point Positioning (PPP) matured and allowed for the reprocessing of the buoy GPS data throughout Katrina. The processed GPS data were corrected for buoy angular motions using Tait Bryan transformation model. Tidal datums (Epoch 1983-2001) were transferred from the National Oceanic and Atmospheric Administration (NOAA) National Water Level at Waveland, Mississippi (Station ID 8747766) to the buoy using the Modified Range Ratio method. The maximum water level during the storm was found to be about 3.578m, relative to the transferred Mean Sea Level datum. The storm surge built over more than 24 hours, but fell back to normal levels in less than 3 hours. The maximum speed of the current with respect to the seafloor was recorded to be about 4knots towards the southeast as the storm surge moved back offshore.

  5. Developing a Pilot Maritime Spatial Plan for the Pomeranian Bight and Arkona Basin

    DEFF Research Database (Denmark)

    Käppeler, Bettina; Toben, Susan; Chmura, Grazyna

    2012-01-01

    This report presents the result of a pilot project carried out as part of the EU-­‐funded BaltSeaPlan project (2009-­‐2011). A team of experts with diverse professional backgrounds worked over a period of two years to draft a pilot transboundary maritime spatial plan for a sea area in the Pomeran......This report presents the result of a pilot project carried out as part of the EU-­‐funded BaltSeaPlan project (2009-­‐2011). A team of experts with diverse professional backgrounds worked over a period of two years to draft a pilot transboundary maritime spatial plan for a sea area...... in the Pomeranian Bight/Arkona Basin. The draft spatial plan is the result of a planning exercise which took place outside the formal planning processes as legally binding agreements already exist for the German EEZ and the territorial waters of Mecklenburg-­‐Vorpommern. Working with diverse stakeholders in Poland...... tangible output, the pilot project was also a test case of working with the MSP planning cycle across national borders, bringing together four different planning systems and traditions in the attempt to come to joint solutions in a sea area faced with multiple pressures. In line with the MSP planning cycle...

  6. Stormwater runoff plumes in the Southern California Bight: A comparison study with SAR and MODIS imagery.

    Science.gov (United States)

    Holt, Benjamin; Trinh, Rebecca; Gierach, Michelle M

    2017-05-15

    Stormwater runoff is the largest source of pollution in the Southern California Bight (SCB), resulting from untreated runoff and pollutants from urban watersheds entering the coastal waters after rainstorms. We make use of both satellite SAR and MODIS-Aqua ocean color imagery to examine two different components of runoff plumes, the surface slick and the sediment discharge. We expand on earlier satellite SAR studies by examining an extensive collection of multi-platform SAR imagery, spanning from 1992 to 2014, that provides a more comprehensive view of the plume surface slick characteristics, illustrated with distribution maps of the extent and flow direction of the plumes. The SAR-detected surface plumes are compared with coincident rain and runoff measurements, and with available measured shoreline fecal bacteria loads. We illustrate differences in the detection of SAR surface plumes with the sediment-related discharge plumes derived from MODIS imagery. A conceptual satellite stormwater runoff monitoring approach is presented. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Parameterization of synoptic weather systems in the South Atlantic Bight for modeling applications

    Science.gov (United States)

    Wu, Xiaodong; Voulgaris, George; Kumar, Nirnimesh

    2017-10-01

    An event based, long-term, climatological analysis is presented that allows the creation of coastal ocean atmospheric forcing on the coastal ocean that preserves both frequency of occurrence and event time history. An algorithm is developed that identifies individual storm event (cold fronts, warm fronts, and tropical storms) from meteorological records. The algorithm has been applied to a location along the South Atlantic Bight, off South Carolina, an area prone to cyclogenesis occurrence and passages of atmospheric fronts. Comparison against daily weather maps confirms that the algorithm is efficient in identifying cold fronts and warm fronts, while the identification of tropical storms is less successful. The average state of the storm events and their variability are represented by the temporal evolution of atmospheric pressure, air temperature, wind velocity, and wave directional spectral energy. The use of uncorrected algorithm-detected events provides climatologies that show a little deviation from those derived using corrected events. The effectiveness of this analysis method is further verified by numerically simulating the wave conditions driven by the characteristic wind forcing and comparing the results with the wave climatology that corresponds to each storm type. A high level of consistency found in the comparison indicates that this analysis method can be used for accurately characterizing event-based oceanic processes and long-term storm-induced morphodynamic processes on wind-dominated coasts.

  8. Seasonal occurrence and abundance of caridean shrimp larvae at Helgoland, German Bight

    Science.gov (United States)

    Wehrtmann, Ingo S.

    1989-03-01

    Plankton samples were collected from January 1985 to January 1986 three times per week at Helgoland to study seasonal occurrence and abundance of caridean shrimp larvae. A total of eleven species were obtained. Ninety-one % of all larvae collected during the sample period belonged to Crangon crangon L. and Crangon allmanni Kinahan, 6% to Philocheras trispinosus Hailstone and 3% to the remaining eight species. Collections were generally dominated by C. crangon larvae. However, C. allmanni larvae were most abundant in June coinciding with hatching activities of the population near Helgoland. C. allmanni was observed to have the highest density of all species with approximately 8 larvae per m3. Larvae of Eualus occultus (Lebour), Eualus pusiolus (Kroyer), Hippolyte varians Leach and Athanas nitescens Leach were most likely released by populations inhabiting the rocky intertidal zone around Helgoland. The presence of Processa modica Williamson & Rochanaburanon and Processa nouveli holthuisi Al-Adhub & Williamson in the German Bight was verified by observations of a series of different developmental stages. Larvae of the rare species Caridion steveni Lebour were also recorded. The observed shrimp species were placed into three different groups with respect to their seasonal occurrence. Possible advantages of the timing of larval dispersal relative to predation and food availability are given. The results on seasonal occurrence and relative abundance are discussed in relation to environmental factors (temperature, salinity) as well as to the geographical distribution of the species.

  9. Resolution of fine biological structure including small narcomedusae across a front in the Southern California Bight

    Science.gov (United States)

    McClatchie, Sam; Cowen, Robert; Nieto, Karen; Greer, Adam; Luo, Jessica Y.; Guigand, Cedric; Demer, David; Griffith, David; Rudnick, Daniel

    2012-04-01

    We sampled a front detected by SST gradient, ocean color imagery, and a Spray glider south of San Nicolas Island in the Southern California Bight between 14 and 18 October 2010. We sampled the front with an unusually extensive array of instrumentation, including the Continuous Underway Fish Egg Sampler (CUFES), the undulating In Situ Ichthyoplankton Imaging System (ISIIS) (fitted with temperature, salinity, oxygen, and fluorescence sensors), multifrequency acoustics, a surface pelagic trawl, a bongo net, and a neuston net. We found higher fluorescence and greater cladoceran, decapod, and euphausiid densities in the front, indicating increased primary and secondary production. Mesopelagic fish were most abundant in oceanic waters to the west of the front, market squid were abundant in the front associated with higher krill and decapod densities, and jack mackerel were most common in the front and on the shoreward side of the front. Egg densities peaked to either side of the front, consistent with both offshore (for oceanic squid and mesopelagic fish) and shelf origins (for white croaker and California halibut). We discovered unusually high concentrations of predatory narcomedusae in the surface layer of the frontal zone. Potential ichthyoplankton predators were more abundant either in the front (decapods, euphausiids, and squid) or shoreward of the front (medusae, chaetognaths, and jack mackerel). For pelagic fish like sardine, which can thrive in less productive waters, the safest place to spawn would be offshore because there are fewer potential predators.

  10. RNA-Based Assessment of Diversity and Composition of Active Archaeal Communities in the German Bight

    Directory of Open Access Journals (Sweden)

    Bernd Wemheuer

    2012-01-01

    Full Text Available Archaea play an important role in various biogeochemical cycles. They are known extremophiles inhabiting environments such as thermal springs or hydrothermal vents. Recent studies have revealed a significant abundance of Archaea in moderate environments, for example, temperate sea water. Nevertheless, the composition and ecosystem function of these marine archaeal communities is largely unknown. To assess diversity and composition of active archaeal communities in the German Bight, seven marine water samples were taken and studied by RNA-based analysis of ribosomal 16S rRNA. For this purpose, total RNA was extracted from the samples and converted to cDNA. Archaeal community structures were investigated by pyrosequencing-based analysis of 16S rRNA amplicons generated from cDNA. To our knowledge, this is the first study combining next-generation sequencing and metatranscriptomics to study archaeal communities in marine habitats. The pyrosequencing-derived dataset comprised 62,045 archaeal 16S rRNA sequences. We identified Halobacteria as the predominant archaeal group across all samples with increased abundance in algal blooms. Thermoplasmatales (Euryarchaeota and the Marine Group I (Thaumarchaeota were identified in minor abundances. It is indicated that archaeal community patterns were influenced by environmental conditions.

  11. Source and distribution of radon-222 and radium-226 within South Atlantic Bight waters

    International Nuclear Information System (INIS)

    Ramsey, E.

    1982-09-01

    Radon and radium concentrations were measured in South Atlantic Bight (SAB) waters during six weeks in the summer of 1981. Sampling was designed to coincide with subsurface intrusions of cold Gulf Stream water onto the continental shelf and was part of a large study of the SAB. The distinct zonation of sediment types within the SAB offered the possibility to use radon to trace advection of intruded bottom water. It was determined that the bottom excess radon concentrations, calculated from radon and radium data, were distributed into three groups. The first group of concentrations ranged from 320 to 732 dpm/100L (n=3) and was associated with water occupying the nearshore zone. The second set was sampled within intruded water in the midshelf region. These values ranged from 25.5 to 151.5 dpm/100L (n=35). The third range describes radon concentrations contained in water that is a potential source of upwelled Gulf Stream water. These shelf break concentrations ranged from -1.0 to 213.0 dpm/100L (n=13), and were found to differ significantly (P < 0.001) from the midshelf range of radon concentrations (Mann-Whitney test). The division of radon concentrations into three distinct zones within the SAB waters may provide an indicator of shelf and Gulf Stream water interactions. 55 references, 24 figures, 4 tables

  12. Beech forests in the Ruhr and in the Westphalian Bight. A comparative study. Buchenwaelder im Ruhrgebiet und in der Westfaelischen Bucht. Eine vergleichende Untersuchung

    Energy Technology Data Exchange (ETDEWEB)

    Wittig, R. (Frankfurt Univ. (Germany, F.R.). Fachbereich 16 - Biologie); Werner, W. (Trier Univ. (Germany, F.R.). Fachbereich 3 - Geographie/Geowissenschaften, Geschichte, Politikwissenschaft, Klassische Archaeologie, Aegyptologie, Kunstgeschichte, Papyrologie)

    1989-01-01

    The Ruhr district, one of the most industrialized and most densely populated regions of Germany, is part of the Westphalian Bight. The potential natural vegetation of the Ruhrgebiet are loess beech forests (Milio-Fagetum), which are also common in other parts of the Westphalian Bight. However, a comparison of the beech forests of the Ruhrgebiet with the Milio-Fagetum stands of other areas of the Westphalian Bight shows distinct differences in floristic composition of the herb layer as well as in C/N ratio and heavy metal contents of the upper 4 cm of the mineral soil. The differences can only be explained by the former long lasting immission load of the Ruhrdistrict. (orig.).

  13. Response of the Mississippi Bight and Sound to the Passage of Tropical Storm Cindy Through the Northern Gulf of Mexico

    Science.gov (United States)

    Hode, L. E.; Howden, S. D.; Diercks, A. R.; Cambazoglu, M. K.; Jones, E. B.; Martin, K. M.

    2017-12-01

    Damage inflicted by tropical storms and hurricanes on coastal communities and industries has become a growing concern in recent decades. Consequently, utilizing products from existing ocean observing platforms, ocean modeling forecasts and satellite data helps to identify the effects of individual storms on the northern Gulf of Mexico. Using data from the jointly-operated United States Geological Survey and Mississippi Department of Marine Resources (USGS-MDMR) hydrological stations, National Oceanic and Atmospheric Administration (NOAA) tide gages, and the Central Gulf of Mexico Ocean Observing System (CenGOOS) high frequency radar (HFR) network, we tracked temperature, salinity, water level and surface current changes in the Mississippi Sound and Bight during June 2017. We performed time series analyses and compared conditions during the buildup and passage of tropical storm Cindy to climatological values as well as to satellite observations and results from a regional application of the Navy Coastal Ocean Model (NCOM). Elevated salinities proceeded Cindy's landfall on June 22, 2017, while anomalously fresh water marked all Mississippi Sound stations afterwards. Onshore surface currents dominated the Mississippi Bight, and current speeds exceeded more than four times the climatological average in the southeastern Bight. Indeed, regions of enhanced current speeds were observed throughout the month of June 2017. Tidal ranges in the Mississippi Sound were on average half a meter higher than predicted, and Shell Beach (Louisiana) and the Bay Waveland Yacht Club (Mississippi) saw extended periods where tides exceeded one meter above predicted values. These results help to quantify the tidal inundation caused by Cindy but also illustrate the massive riverine discharge driven by the storm's precipitation. Model results provide information on areas of the study region not covered by measurements; additionally, comparing observations to model products helps estimate model

  14. Simulation of the 1979 spring bloom in the Mid-Atlantic Bight - A coupled physical/biological/optical model

    Science.gov (United States)

    Gregg, Watson W.; Walsh, John J.

    1992-01-01

    A coupled physical/biological/optical model is developed for studies of phytoplankton variability in the spring 1979 Mid-Atlantic Bight, as observed by CZCS imagery. The model incorporates advection, mixing, sinking, growth as a function of light, temperature, nutrient availability, and death as a function of ingestion. It produced chlorophyll concentrations within the first attenuated depth within 1 standard deviation of CZCS imagery on large scale. The primary production estimates obtained using this model were within reasonable agreement with those measured in situ.

  15. Numerical diagnostic of the circulation in the Santos Bight with COROAS hydrographic data

    Directory of Open Access Journals (Sweden)

    Mauro Cirano

    1996-01-01

    Full Text Available This work represents part of the analyses of the data generated during the first two mesoscale hydrographic cruises of COROAS Project: one during the Summer and the other during the Winter of 1993. The area surveyed during these cruises is the region of the South Brazil Bight (or Santos Bight limited at the coast by the cities of Ubatuba and Iguape, extending from the 50 m isobath to oceanic regions with depths greater than 2500 m. The main goal of this work consisted of the adaptation of the Princeton Ocean Model to the area of study, including realistic topography, observed thermohaline structure and open boundaries. Using this model, a set of diagnostic experiments was realized using density structures based on the COROAS hydrographic data. The baroclinic velocity fields obtained, as expected from preliminary analyses of the thermohaline structures, showed similar features for the Brazil Current in bOla seasonal cruises. The results show an intrusion of Tropical Water over the continental shelf in the region between Ubatuba and Santos, both during the Summer and the Winter cruises. The results also suggest the penetration of the South Atlantic Central Water, underneath the Tropical Water, to the external part of the continental shelf in both occasions.Este artigo representa parte das análises desenvolvidas com os dados hidrográficos coletados durante os dois primeiros cruzeiros do sub-projeto Hidrografia de Meso-escala (HM do Projeto COROAS: o primeiro no verão e o outro no inverno de 1993. A área amostrada nos dois cruzeiros é limitada na costa pelas cidades de Iguape e Ubatuba, estendendo-se da isóbata de 50 m até regiões oceânicas com mais de 2500 m de profundidade. O objetivo central deste trabalho resumiu-se na adaptação do Princeton Ocean Model para a região de estudo, incluindo batimetria real, os campos termohalinos observados e contornos abertos. Usando-se esse modelo, realizou-se um conjunto de experimentos diagn

  16. Provenance of Holocene calcareous beach-dune sediments, Western Eyre Peninsula, Great Australian Bight, Australia

    Science.gov (United States)

    James, Noel P.; Bone, Yvonne

    2017-07-01

    Much of western Eyre Peninsula adjacent to the Great Australian Bight is veneered with siliceous and calcareous Quaternary aeolian dunes. The lengthy coastline adjacent to this cool-water carbonate factory is a series of Precambrian crystalline bedrock-Pleistocene aeolianite headlands that separate many long, sweeping, Holocene carbonate sand beaches and their backbeach dunes. Incessant SW waves, rolling swells, and onshore winds have resulted in > 350 km of semi-continuous calcareous strandline aeolian sands. The sediment is composed of quartz grains, Cenozoic limestone clasts, and relict particles (extraclasts) but the deposits are overwhelmingly dominated by contemporaneous biofragments from offshore. These skeletal grains are, in order of relative abundance, molluscs > benthic foraminifers > coralline algae > bryozoans, and echinoids. Benthic foraminifers are mostly small (especially rotaliids and miliolids) but the large relict symbiont-bearing protistMarginopora vertebralis, which grew in the latter stages of MIS 2, is present locally. There are no significant onshore-offshore trends within individual beach-dune complexes. There is, however, a prominent spatial partitioning, with extraclast-rich sediments in the north and biofragment-rich deposits in the south. This areal trend is interpreted to result from more active seafloor carbonate production in the south, an area of conspicuous seasonal nutrient upwelling and profound nektic and benthic biological productivity. The overall system is strikingly similar to Holocene and Pleistocene aeolianites along the inboard margin of the Lacepede Shelf and Bonney Coast some 500 km to the southeast, implying a potential universality to the nature of cool-water carbonate aeolianite deposition. The composition of these cool-water aeolianites is more multifaceted than those formed on warm-water, shallow flat-topped platforms, largely because of the comparatively deep, temperate shelf, the high-energy wave and swell

  17. Chemical composition and cycling of dissolved organic matter in the Mid-Atlantic Bight

    Science.gov (United States)

    Aluwihare, Lihini I.; Repeta, Daniel J.; Chen, Robert F.

    This study focuses on the chemical characterization of high molecular-weight dissolved organic matter (HMW DOM) isolated from the Middle Atlantic Bight in April 1994 and March 1996. Using proton nuclear magnetic resonance spectroscopy ( 1HNMR) and monosaccharide analysis we compared both spatial and temporal variations in the chemical structure of HMW DOM across this region. Our analyses support the presence of at least two compositionally distinct components to HMW DOM. The major component is acyl polysaccharide (APS), a biopolymer rich in carbohydrates, acetate and lipid, accounting for between 50% and 80% of the total high molecular-weight dissolved organic carbon (HMW DOC) in surface samples. APS is most abundant in fully marine, surface-water samples, and is a product of autochthonous production. Organic matter with spectral properties characteristic of humic substances is the second major component of HMW DOM. Humic substances are most abundant (up to 49% of the total carbon) in samples collected from estuaries, near the coast, and in deep water, suggesting both marine and perhaps terrestrial sources. Radiocarbon analyses of neutral monosaccharides released by the hydrolysis of APS have similar and modern (average 71‰) Δ 14C values. Radiocarbon data support our suggestion that these sugars occur as part of a common macromolecule, with an origin via recent biosynthesis. Preliminary radiocarbon data for total neutral monosaccharides isolated from APS at 300 and 750 m show this fraction to be substantially enriched relative to total HMW DOC and DOC. The relatively enriched radiocarbon values of APS at depth suggest APS is rapidly transported into the deep ocean.

  18. Anthropogenic nutrient sources rival natural sources on small scales in the coastal waters of the Southern California Bight

    KAUST Repository

    Howard, Meredith D. A.

    2014-01-26

    Anthropogenic nutrients have been shown to provide significant sources of nitrogen (N) that have been linked to increased primary production and harmful algal blooms worldwide. There is a general perception that in upwelling regions, the flux of anthropogenic nutrient inputs is small relative to upwelling flux, and therefore anthropogenic inputs have relatively little effect on the productivity of coastal waters. To test the hypothesis that natural sources (e.g., upwelling) greatly exceed anthropogenic nutrient sources to the Southern California Bight (SCB), this study compared the source contributions of N from four major nutrient sources: (1) upwelling, (2) treated wastewater effluent discharged to ocean outfalls, (3) riverine runoff, and (4) atmospheric deposition. This comparison was made using large regional data sets combined with modeling on both regional and local scales. At the regional bight-wide spatial scale, upwelling was the largest source of N by an order of magnitude to effluent and two orders of magnitude to riverine runoff. However, at smaller spatial scales, more relevant to algal bloom development, natural and anthropogenic contributions were equivalent. In particular, wastewater effluent and upwelling contributed the same quantity of N in several subregions of the SCB. These findings contradict the currently held perception that in upwelling-dominated regions anthropogenic nutrient inputs are negligible, and suggest that anthropogenic nutrients, mainly wastewater effluent, can provide a significant source of nitrogen for nearshore productivity in Southern California coastal waters.

  19. Anthropogenic nutrient sources rival natural sources on small scales in the coastal waters of the Southern California Bight

    KAUST Repository

    Howard, Meredith D. A.; Sutula, Martha; Caron, David A.; Chao, Yi; Farrara, John D.; Frenzel, Hartmut; Jones, Burton; Robertson, George; McLaughlin, Karen; Sengupta, Ashmita

    2014-01-01

    Anthropogenic nutrients have been shown to provide significant sources of nitrogen (N) that have been linked to increased primary production and harmful algal blooms worldwide. There is a general perception that in upwelling regions, the flux of anthropogenic nutrient inputs is small relative to upwelling flux, and therefore anthropogenic inputs have relatively little effect on the productivity of coastal waters. To test the hypothesis that natural sources (e.g., upwelling) greatly exceed anthropogenic nutrient sources to the Southern California Bight (SCB), this study compared the source contributions of N from four major nutrient sources: (1) upwelling, (2) treated wastewater effluent discharged to ocean outfalls, (3) riverine runoff, and (4) atmospheric deposition. This comparison was made using large regional data sets combined with modeling on both regional and local scales. At the regional bight-wide spatial scale, upwelling was the largest source of N by an order of magnitude to effluent and two orders of magnitude to riverine runoff. However, at smaller spatial scales, more relevant to algal bloom development, natural and anthropogenic contributions were equivalent. In particular, wastewater effluent and upwelling contributed the same quantity of N in several subregions of the SCB. These findings contradict the currently held perception that in upwelling-dominated regions anthropogenic nutrient inputs are negligible, and suggest that anthropogenic nutrients, mainly wastewater effluent, can provide a significant source of nitrogen for nearshore productivity in Southern California coastal waters.

  20. Case study of conservation and community concerns for present and future multiple use of the Great Australian Bight

    Energy Technology Data Exchange (ETDEWEB)

    Flaherty, T. [Marine and Coastal Community Network, Henley Beach, SA (Australia)

    1996-12-31

    As part of the Australian National Strategy for ecologically sustainable development, State and Federal Governments have agreed to cooperate on action under the Ocean Rescue 2000 Program to develop a national representative system of Marine Protected Areas. As a component of this program an area of the Great Australian Bight has been the focus of a proposal for a large area multiple use marine park. Within the context of this workshop, however, the conservation and community considerations extend beyond this proposed area. There is a need for resolution of apparent and real conflict with conservation, fishing, tourism and mining objectives in the development of equitable policies in establishing a marine protected area for the significant region. In this paper current activities in the Great Australian Bight, conservation values and concerns, fisheries and conservation, and fisheries and potential conflict with future petroleum exploitation, are discussed. The marine animals of the area are outlined, and community conservation concerns are detailed. It is concluded that there is an increasing need for States to develop a strategic approach to marine management. The adoption of marine bio-regionalisation methodology to define areas of significant biodiversity, representative marine protected areas and the development of a marine conservation and management strategy can be seen as essential components in the management of the marine environment. (author). refs.

  1. Archive of Boomer Subbottom Data Collected During USGS Cruise SEAX 96004, New York Bight, 1 May - 9 June 1996

    Science.gov (United States)

    Hill, Jenna C.; Schwab, William C.; Foster, David S.

    2000-01-01

    Beginning in 1995, the USGS, in cooperation with the U.S Army Corps of Engineers (USACE), New York District, began a program to generate reconnaissance maps of the sea floor offshore of the New York-New Jersey metropolitan area, one of the most populated coastal regions of the United States. The goal of this mapping program is to provide a regional synthesis of the sea-floor environment, including a description of sedimentary environments, sediment texture, seafloor morphology, and geologic history to aid in understanding the impacts of anthropogenic activities, such as ocean dumping. This mapping effort differs from previous studies of this area by obtaining digital, sidescan sonar images that cover 100 percent of the sea floor.This investigation was motivated by the need to develop an environmentally acceptable solution for the disposal of dredged material from the New York - New Jersey Port, by the need to identify potential sources of sand for renourishment of the southern shore of Long island, and by the opportunity to develop a better understanding of the transport and long-term fate of contaminants by investigations of the present distribution of materials discharged into the New York Bight over the last 100+ years (Schwab and others, 1997). Data collected in 1996, USGS cruise SEAX 96004, augments data collected in 1995 with sidescan sonar and seismic reflection data collected within the New York Bight Apex region. This report is an archive of the boomer seismic reflection data collected in 1996.

  2. Archive of water gun subbottom data collected during USGS cruise SEAX 96004, New York Bight, 1 May - 9 June 1996

    Science.gov (United States)

    Hill, Jenna C.; Schwab, William C.; Foster, David S.

    2000-01-01

    Beginning in 1995, the USGS, in cooperation with the U.S Army Corps of Engineers (USACE), New York District, began a program to generate reconnaissance maps of the sea floor offshore of the New York-New Jersey metropolitan area, one of the most populated coastal regions of the United States. The goal of this mapping program is to provide a regional synthesis of the sea-floor environment, including a description of sedimentary environments, sediment texture, seafloor morphology, and geologic history to aid in understanding the impacts of anthropogenic activities, such as ocean dumping. This mapping effort differs from previous studies of this area by obtaining digital, sidescan sonar images that cover 100 percent of the sea floor.This investigation was motivated by the need to develop an environmentally acceptable solution for the disposal of dredged material from the New York - New Jersey Port, by the need to identify potential sources of sand for renourishment of the southern shore of Long island, and by the opportunity to develop a better understanding of the transport and long-term fate of contaminants by investigations of the present distribution of materials discharged into the New York Bight over the last 100+ years (Schwab and others, 1997). Data collected in 1996, USGS cruise SEAX 96004, augments data collected in 1995 with sidescan sonar and seismic reflection data collected within the New York Bight Apex region. This report is an archive of the water gun seismic reflection data collected in 1996.

  3. The assessment of optimal MERIS ocean colour products in the shelf waters of the KwaZulu-Natal Bight, South Africa

    CSIR Research Space (South Africa)

    Smith, ME

    2013-10-01

    Full Text Available The KwaZulu-Natal Bight is a highly variable bio-optical environment, where waters over the shelf can change from the oligotrophic case 1 conditions of the Agulhas Current to the case 2 inshore environment influenced by upwelling and riverine influx...

  4. Dissolved methane concentration and flux in the coastal zone of the Southern California Bight-Mexican sector: Possible influence of wastewater

    Science.gov (United States)

    We measured dissolved methane concentrations ([CH4]) in the coastal zone of the Southern California Bight-Mexican sector (SCBMex) during two cruises: S1 in the USA–Mexico Border Area (BA) during a short rainstorm and S2 in the entire SCBMex during a drier period a few days later....

  5. Terrestrially derived dissolved organic matter in the chesapeake bay and the middle atlantic bight

    Science.gov (United States)

    Mitra, Siddhartha; Bianchi, Thomas S.; Guo, Laodong; Santschi, Peter H.

    2000-10-01

    Concentrations of lignin-phenols were analyzed in high molecular weight dissolved organic matter (0.2 μm > HMW DOM > 1 kDa) isolated from surface waters of the Chesapeake Bay (C. Bay), and surface and bottom waters of the Middle Atlantic Bight (MAB). The abundance of lignin-phenols in HMW DOM was higher in the C. Bay (0.128 ± 0.06 μg L -1) compared to MAB surface waters (0.016 ± 0.004 μg L -1) and MAB bottom waters (0.005 ± 0.003 μg L -1). On an organic carbon-normalized basis, lignin-phenol abundances in the HMW DOM (i.e., Λ 6), were significantly higher ( p vanillin (Ad/Al) V in HMW DOM, indicative of lignin decay, ranged from 0.611 to 1.37 in C. Bay, 0.534 to 2.62 in MAB surface waters, and 0.435 to 1.96 in MAB bottom water. Ratios of S/V and (Ad/Al) V showed no significant differences between each environment, providing no evidence of any compositionally distinct input of terrestrial organic matter into each environment. When considering depth profiles of suspended particulate matter in the MAB, with C:N ratios, and bulk radiocarbon ages and stable carbon isotopic values in HMW DOM isolated from these areas, two scenarios present themselves regarding the sources and transport of terrestrially derived HMW DOM in the MAB. Scenario #1 assumes that a low amount of refractory terrestrial organic matter and old DOC are uniformly distributed in the oceans, both in surface and bottom waters, and that primary production in surface waters increases DOC with low lignin and younger DOC which degrades easily. In this case, many of the trends in age and biomarker composition likely reflect general patterns of Atlantic Ocean surface and bottom water circulation in the area of the MAB. Scenario 2 assumes terrestrial organic matter in bottom waters of the MAB may have originated from weathered shelf and slope sediments in nearshore areas via a combination of mechanisms (e.g., diffusion, recent resuspension events, and/or desorption of DOM from riverine POM buried deep

  6. Coastal observing and forecasting system for the German Bight – estimates of hydrophysical states

    Directory of Open Access Journals (Sweden)

    W. Petersen

    2011-09-01

    Full Text Available A coastal observing system for Northern and Arctic Seas (COSYNA aims at construction of a long-term observatory for the German part of the North Sea, elements of which will be deployed as prototype modules in Arctic coastal waters. At present a coastal prediction system deployed in the area of the German Bight integrates near real-time measurements with numerical models in a pre-operational way and provides continuously state estimates and forecasts of coastal ocean state. The measurement suite contributing to the pre-operational set up includes in situ time series from stationary stations, a High-Frequency (HF radar system measuring surface currents, a FerryBox system and remote sensing data from satellites. The forecasting suite includes nested 3-D hydrodynamic models running in a data-assimilation mode, which are forced with up-to-date meteorological forecast data. This paper reviews the present status of the system and its recent upgrades focusing on developments in the field of coastal data assimilation. Model supported data analysis and state estimates are illustrated using HF radar and FerryBox observations as examples. A new method combining radial surface current measurements from a single HF radar with a priori information from a hydrodynamic model is presented, which optimally relates tidal ellipses parameters of the 2-D current field and the M2 phase and magnitude of the radials. The method presents a robust and helpful first step towards the implementation of a more sophisticated assimilation system and demonstrates that even using only radials from one station can substantially benefit state estimates for surface currents. Assimilation of FerryBox data based on an optimal interpolation approach using a Kalman filter with a stationary background covariance matrix derived from a preliminary model run which was validated against remote sensing and in situ data demonstrated the capabilities of the pre-operational system. Data

  7. Temperature and other data collected using visual observations and other instruments in the Mid-Atlantic Bight and other Seas from GYRE from 01 August 1985 to 26 May 1990 (NODC Accession 9300074)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature and other data were collected using visual observations, bottle casts, and other instruments from GYRE and other platforms in the Mid-Atlantic Bight and...

  8. Physical, taxonomic code, and other data from current meter and other instruments in New York Bight from DOLPHIN and other platforms; 14 March 1971 to 03 August 1975 (NODC Accession 7601385)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Physical, taxonomic code, and other data were collected using current meter and other instruments from DOLPHIN and other platforms in New York Bight. Data were...

  9. Taxonomic code, physical, and other data collected from NOAA Ship DELAWARE II and other platforms in New York Bight from net casts and other instruments; 1973-02-20 to 1975-12-16 (NODC Accession 7601402)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Taxonomic Code, physical, and other data were collected using net casts and other instruments in the New York Bight from NOAA Ship DELAWARE II and other platforms....

  10. Physical trajectory profile data from glider ru23 deployed by Rutgers, the State University of New Jersey in the Mid-Atlantic Bight from 2012-10-25 to 2012-11-05 (NCEI Accession 0145723)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Slocum glider ru23 was deployed prior to the movement of Hurrican Sandy into the Mid-Atlantic Bight and was deployed to sample the sub-surface waters during the...

  11. HYDROCARBONS - TOTAL RESOLVED, CAS (CHEMICAL ABSTRACTS SERVICE) PARAMETER CODES and PCB, and other data from UNKNOWN in the New York Bight on 1901-01-01 (NODC Accession 8600271)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This submission contains the master data set assembled in a study called "Contaminant Body Burdens, Variability and Monitoring Implications for the New York Bight"....

  12. Food and feeding ecology of Brazilian sardine (Sardinella brasiliensis larvae from the southeastern Brazilian Bight

    Directory of Open Access Journals (Sweden)

    Frederico W. Kurtz

    2001-01-01

    Full Text Available Results from depth integrated and vertically stratified plankton samples collected in the southeastern Brazilian Bight were used to study the feeding behavior of Brazilian sardine (Sardinella brasiliensis larvae. Sampling of the ichthyoplankton was carried out with 60 cm Bongo nets in the Bight during the spawning seasons of 1991/92 and 1992/93. The sampling of microzooplankton was carried out in the coastal region off Ubatuba, using the closing-type plankton net, in December 1995. The feeding study was based on a total of 901 captured larvae. Gut content analysis of the sardine larvae showed a diurnal pattern of food intake. Copepod nauplii dominated the diet of the preflexion and flexion larvae, but they were the second in abundance for the postflexion larvae which fed preferentially on copepodites and adults of Oncaea spp. Averaged feeding incidence of the 901 larvae was 37.6%, but it increased to 58.5% for day-caught larvae. Seventy percent of the food particles were found in the mid-gut and food eaten showed a natural increase in digestion from fore-gut to hind-gut. Vertical distribution of microzooplankton revealed that copepod nauplii were present in densities of 10-20 ind. L-1, mainly in the upper mixed layer (0-20 m depth, but higher densities of copepodite and adult of Oncaea, Oithona and Paracalamis were found within and beneath the thermocline. These results show that Brazilian sardine larvae can successfully adapt their diet, feeding on the most abundant food particles in the upper mixed layer of the survey area.Plâncton amostrado na região sudeste do Brasil, em coletas integradas verticalmente e estratificadas, foi utilizado no estudo do comportamento alimentar das larvas de sardinha-verdadeira (Sardinella brasiliensis. As coletas de ictioplâncton foram realizadas com rede tipo Bongo de 60 cm de diâmetro durante os períodos de desova de 1991/92 e 1992/93. Microzooplâncton foi amostrado na região costeira ao largo de Ubatuba

  13. Ecological evaluation of proposed reference sites in the New York Bight, Great South Bay, and Ambrose Light, New York

    Energy Technology Data Exchange (ETDEWEB)

    Gardiner, W.W.; Barrows, E.S.; Word, J.Q. [Battelle Marine Research Lab., Sequim, WA (United States)

    1996-10-01

    The current reference site used in evaluations of dredged material proposed for open water disposal in the New York Bight is the Mud Dump Reference Site. The sediment at this reference site is predominantly sand. The US Army Corps of Engineers New York District is considering designation of a new reference site that (1) includes a fine-grained component, believed to be necessary for adequate amphipod survival in laboratory tests, (2) better reflects the physical characteristics of the fine-grained sediment dredged from the New York/New Jersey Harbor and (3) is further removed from the Mud Dump Site than the current Mud Dump Reference Site. The Battelle Marine Science Laboratory was requested to characterize sediment collected from seven candidate reference sites during two study phases. This report presents the results of physical, chemical, and toxicological characterizations of sediment from these sites in comparisons with those of the original Mud Dump Reference Site.

  14. Coastal flooding: impact of waves on storm surge during extremes – a case study for the German Bight

    Directory of Open Access Journals (Sweden)

    J. Staneva

    2016-11-01

    Full Text Available This study addresses the impact of wind, waves, tidal forcing and baroclinicity on the sea level of the German Bight during extreme storm events. The role of wave-induced processes, tides and baroclinicity is quantified, and the results are compared with in situ measurements and satellite data. A coupled high-resolution modelling system is used to simulate wind waves, the water level and the three-dimensional hydrodynamics. The models used are the wave model WAM and the circulation model GETM. The two-way coupling is performed via the OASIS3-MCT coupler. The effects of wind waves on sea level variability are studied, accounting for wave-dependent stress, wave-breaking parameterization and wave-induced effects on vertical mixing. The analyses of the coupled model results reveal a closer match with observations than for the stand-alone circulation model, especially during the extreme storm Xaver in December 2013. The predicted surge of the coupled model is significantly enhanced during extreme storm events when considering wave–current interaction processes. This wave-dependent approach yields a contribution of more than 30 % in some coastal areas during extreme storm events. The contribution of a fully three-dimensional model compared with a two-dimensional barotropic model showed up to 20 % differences in the water level of the coastal areas of the German Bight during Xaver. The improved skill resulting from the new developments justifies further use of the coupled-wave and three-dimensional circulation models in coastal flooding predictions.

  15. Sediment accumulation on the Southern California Bight continental margin during the twentieth century

    Science.gov (United States)

    Alexander, C.R.; Lee, H.J.

    2009-01-01

    Sediment discharged into the portion of the Southern California Bight extending from Santa Barbara to Dana Point enters a complex system of semi-isolated coastal cells, narrow continental shelves, submarine canyons, and offshore basins. On both the Santa Monica and San Pedro margins, 210Pb accumulation rates decrease in an offshore direction (from ??0.5 g cm-2yr-1 to 0.02 g cm-2yr -1), in concert with a fining in sediment grain size (from 4.5?? to 8.5??), suggesting that offshore transport of wave-resuspended material occurs as relatively dilute nepheloid layers and that hemiplegic sedimentation dominates the supply of sediment to the outer shelf, slope, and basins. Together, these areas are effectively sequestering up to 100% of the annual fluvial input. In contrast to the Santa Monica margin, which does not display evidence of mass wasting as an important process of sediment delivery and redistribution, the San Pedro margin does provide numerous examples of failures and mass wasting, suggesting that intraslope sediment redistribution may play a more important role there. Basin deposits in both areas exhibit evidence of turbidites tentatively associated with both major floods and earthquakes, sourced from either the Redondo Canyon (San Pedro Basin) or Dume Canyon (Santa Monica Basin). On the Palos Verdes shelf, sediment-accumulation rates decrease along and across the shelf away from the White's Point outfall, which has been a major source of contaminants to the shelf deposits. Accumulation rates prior to the construction of the outfall were ??0.2 g cm-2yr-1 and increased 1.5-3.7 times during peak discharges from the outfall in 1971. The distal rate of accumulation has decreased by ??50%, from 0.63 g cm -2yr-1 during the period 1971-1992 to 0.29 g cm -2yr-1 during the period 1992-2003. The proximal rate of accumulation, however, has only decreased ??10%, from 0.83 g cm -2yr-1 during the period 1971-1992 to 0.73 g cm -2yr-1 during the period 1992-2003. Effluent

  16. Wind effects on coastal zone color scanner chlorophyll patterns in the U.S. Mid-Atlantic Bight during spring 1979

    Science.gov (United States)

    Eslinger, David L.; Iverson, Richard L.

    1986-01-01

    Coastal zone color scanner (CZCS) chlorophyll concentration increases in the Mid-Atlantic Bight were associated with high wind speeds in continental shelf waters during March and May 1979. Maximum spring CZCS chlorophyll concentrations occurred during April when the water column was not thermally stratified and were spatially and temporally associated with reductions in wind speed both in onshelf and in offshelf regions. Increased chlorophyll concentrations in offshelf waters were associated with high wind speeds during May when a deep chlorophyll maximum was present. Chlorophyll patchiness was observed on length scales typical of those controlled by biological processes during the April low-wind period but not during March or May when wind speeds were greater. The spring CZCS chlorophyll maximum in the southern portion of the Mid-Atlantic Bight occurred in response to a reduction in mixed layer depth caused by decreased wind speeds and not by increased water column stratification.

  17. Inferring seawater temperature over the past 2,500 years in the Southern California Bight on the basis of brachiopods

    Science.gov (United States)

    Tomašových, Adam; Müller, Tamás; Kidwell, Susan M.

    2017-04-01

    Use of calcite δ18O in brachiopod shells in assessing past variations in seawater temperature remains poorly constrained in the absence of other methods due to vital effects and unknown variations in seawater density, salinity. Here, in order to evaluate past changes in seawater temperature of mainland shelf habitats off the Southern California Bight over the past 2,500 years, we analyze δ18O and Mg/Ca ratio of dead shells of the terebratulid brachiopod Laqueus erythraeus collected at 60-80 m water depths and age-dated by radiocarbon-calibrated amino acid racemization. These dead Holocene shells show excellent preservation (Mn concentrations < 10 ppm and Sr concentrations above 800 ppm). Although historical changes in sea-surface temperature in the southern California Bight were inferred on the basis of alkenones and δ18O in of planktonic foraminifers, temperature history of deeper shelf below storm wave base in this region remains unclear. First, we investigate thermal sensitivity of Mg/Ca ratio (using Laser Ablation Inductively Coupled Plasma Mass Spectrometry and wavelength-dispersive spectrometry) in the terebratulid brachiopod Laqueus erythraeus (collected in 1994 at Santa Catalina Island at 116 m water depth). At this depth, annual temperature range is relatively small (between 9-11°C), although at times of El Nino events in 1982-1983, 1986-1987, and 1992-1993, monthly temperature attained 13 °C. We find that δ18O measured along a growth profile of a shell precipitated in oxygen isotopic equilibrium with ambient seawater, and maxima in Mg/Ca ratio coincide with minima in δ18O, suggesting that fluctuations in Mg/Ca ratio trace temperature fluctuations, as observed also in other brachiopod species. Second, preliminary observations of Holocene shells show that Mg/Ca ratios show centennial-scale fluctuations but on average remain remarkably constant, with minima and maxima staying within intra-shell seasonal variations captured by extant specimens

  18. Nitrate Sources, Supply, and Phytoplankton Growth in the Great Australian Bight: An Eulerian-Lagrangian Modeling Approach

    Science.gov (United States)

    Cetina-Heredia, Paulina; van Sebille, Erik; Matear, Richard J.; Roughan, Moninya

    2018-02-01

    The Great Australian Bight (GAB), a coastal sea bordered by the Pacific, Southern, and Indian Oceans, sustains one of the largest fisheries in Australia but the geographical origin of nutrients that maintain its productivity is not fully known. We use 12 years of modeled data from a coupled hydrodynamic and biogeochemical model and an Eulerian-Lagrangian approach to quantify nitrate supply to the GAB and the region between the GAB and the Subantarctic Australian Front (GAB-SAFn), identify phytoplankton growth within the GAB, and ascertain the source of nitrate that fuels it. We find that nitrate concentrations have a decorrelation timescale of ˜60 days; since most of the water from surrounding oceans takes longer than 60 days to reach the GAB, 23% and 75% of nitrate used by phytoplankton to grow are sourced within the GAB and from the GAB-SAFn, respectively. Thus, most of the nitrate is recycled locally. Although nitrate concentrations and fluxes into the GAB are greater below 100 m than above, 79% of the nitrate fueling phytoplankton growth is sourced from above 100 m. Our findings suggest that topographical uplift and stratification erosion are key mechanisms delivering nutrients from below the nutricline into the euphotic zone and triggering large phytoplankton growth. We find annual and semiannual periodicities in phytoplankton growth, peaking in the austral spring and autumn when the mixed layer deepens leading to a subsurface maximum of phytoplankton growth. This study highlights the importance of examining phytoplankton growth at depth and the utility of Lagrangian approaches.

  19. Assessing Phytoplankton Nutritional Status and Potential Impact of Wet Deposition in Seasonally Oligotrophic Waters of the Mid-Atlantic Bight

    Science.gov (United States)

    Sedwick, P. N.; Bernhardt, P. W.; Mulholland, M. R.; Najjar, R. G.; Blumen, L. M.; Sohst, B. M.; Sookhdeo, C.; Widner, B.

    2018-04-01

    To assess phytoplankton nutritional status in seasonally oligotrophic waters of the southern Mid-Atlantic Bight, and the potential for rain to stimulate primary production in this region during summer, shipboard bioassay experiments were performed using natural seawater and phytoplankton collected north and south of the Gulf Stream. Bioassay treatments comprised iron, nitrate, iron + nitrate, iron + nitrate + phosphate, and rainwater. Phytoplankton growth was inferred from changes in chlorophyll a, inorganic nitrogen, and carbon-13 uptake, relative to unamended control treatments. Results indicated the greatest growth stimulation by iron + nitrate + phosphate, intermediate growth stimulation by rainwater, modest growth stimulation by nitrate and iron + nitrate, and no growth stimulation by iron. Based on these data and analysis of seawater and atmospheric samples, nitrogen was the proximate limiting nutrient, with a secondary limitation imposed by phosphorus. Our results imply that summer rain events increase new production in these waters by contributing nitrogen and phosphorus, with the availability of the latter setting the upper limit on rain-stimulated new production.

  20. Trophic model of the outer continental shelf and upper slope demersal community of the southeastern Brazilian Bight

    Directory of Open Access Journals (Sweden)

    Marcela C. Nascimento

    2012-10-01

    Full Text Available It is increasingly recognized that demersal communities are important for the functioning of continental shelf and slope ecosystems around the world, including tropical regions. Demersal communities are most prominent in areas of high detritus production and transport, and they link benthic and pelagic biological communities. To understand the structure and role of the demersal community on the southeastern Brazilian Bight, we constructed a trophodynamic model with 37 functional groups to represent the demersal community of the outer continental shelf and upper slope of this area, using the Ecopath with Ecosim 6 (EwE approach and software. The model indicates high production and biomass of detritus and benthic invertebrates, and strong linkages of these components to demersal and pelagic sub-webs. The level of omnivory indexes in this ecosystem was high, forming a highly connected trophic web reminiscent of tropical land areas. Although high levels of ascendency may indicate resistance and resilience to disturbance, recent and present fisheries trends are probably degrading the biological community and related ecosystem services.

  1. Spawning areas of Engraulis anchoita in the Southeastern Brazilian Bight during late-spring and early summer

    Science.gov (United States)

    del Favero, Jana M.; Katsuragawa, Mario; Zani-Teixeira, Maria de Lourdes; Turner, Jefferson T.

    2017-04-01

    Analysis of fish egg density and distribution is indispensable for the understanding of the adult stock variability, and is a powerful tool for fisheries management. Thus, the objective of the present study was to characterize the spatial-temporal spawning patterns of Engraulis anchoita in the Southeastern Brazilian Bight, in terms of geographic location and abiotic factors. We analyzed data of eggs sampled during ten years, from 1974 to 1993, to create maps of the mean and the standard deviation (sd) of the estimated probability of egg presence, through indicative kriging. Preferred, tolerated and avoided temperature, salinity, local depth and distance for spawning of E. anchoita were defined by the estimation of bootstrapped confidence intervals of the quotient values (Q). Despite not having identified any recurrent spawning sites, a few occasional and unfavorable spawning sites were identified, showing that the spawning habit of E. anchoita not only varied spatially, but also temporally. The largest occasional spawning site and with the highest probability of egg presence (0.6-0.7) was located around 27°S, close to Florianópolis (Santa Catarina state). On the other hand, a well-marked unfavorable spawning site was located off São Sebastião Island (São Paulo state), with the probability of egg presence between 0-0.1. Abiotic and biotic factors that could be related to the changes in the spawning areas of E. anchoita were discussed, with shelf width, mesoscale hydrodynamic features and biological interactions apparently playing important roles in defining spawning sites.

  2. Analysis of phytoplankton distribution and community structure in the German Bight with respect to the different size classes

    Science.gov (United States)

    Wollschläger, Jochen; Wiltshire, Karen Helen; Petersen, Wilhelm; Metfies, Katja

    2015-05-01

    Investigation of phytoplankton biodiversity, ecology, and biogeography is crucial for understanding marine ecosystems. Research is often carried out on the basis of microscopic observations, but due to the limitations of this approach regarding detection and identification of picophytoplankton (0.2-2 μm) and nanophytoplankton (2-20 μm), these investigations are mainly focused on the microphytoplankton (20-200 μm). In the last decades, various methods based on optical and molecular biological approaches have evolved which enable a more rapid and convenient analysis of phytoplankton samples and a more detailed assessment of small phytoplankton. In this study, a selection of these methods (in situ fluorescence, flow cytometry, genetic fingerprinting, and DNA microarray) was placed in complement to light microscopy and HPLC-based pigment analysis to investigate both biomass distribution and community structure of phytoplankton. As far as possible, the size classes were analyzed separately. Investigations were carried out on six cruises in the German Bight in 2010 and 2011 to analyze both spatial and seasonal variability. Microphytoplankton was identified as the major contributor to biomass in all seasons, followed by the nanophytoplankton. Generally, biomass distribution was patchy, but the overall contribution of small phytoplankton was higher in offshore areas and also in areas exhibiting higher turbidity. Regarding temporal development of the community, differences between the small phytoplankton community and the microphytoplankton were found. The latter exhibited a seasonal pattern regarding number of taxa present, alpha- and beta-diversity, and community structure, while for the nano- and especially the picophytoplankton, a general shift in the community between both years was observable without seasonality. Although the reason for this shift remains unclear, the results imply a different response of large and small phytoplankton to environmental influences.

  3. Assessing the effect of nutrient mitigation measures in the watersheds of the Southern Bight of the North Sea.

    Science.gov (United States)

    Thieu, Vincent; Garnier, Josette; Billen, Gilles

    2010-02-15

    The Seine, Somme, and Scheldt Rivers (France, Belgium, and Netherlands) are the major delivering rivers flowing into the continental coastal zone of the Southern Bight of the North Sea, an area regularly affected by eutrophication problems. In the present work, the Seneque-Riverstrahler model was implemented in a multi-regional case study in order to test several planned mitigation measures aimed at limiting stream nutrient contamination and restoring balanced nutrient ratios at the coastal zone. This modeling approach, which is spatially distributed at the basin scale, allows assessing the impact of any change in human activities, which widely differ over the three basins. Here, we define realistic scenarios based on currently proposed measures to reduce point and non-point sources, such as the upgrading of wastewater treatment, the introduction of catch crops, and the development of extensive farming. An analysis of the current situation showed that a 47-72% reduction in P point-source emissions within the three basins could be reached if the intended P treatment was generalized to the largest treatment plants. However, only an overall 14-23% reduction in N could be achieved at the outlet of the three basins, by combining improved wastewater treatment and land use with management measures aimed at regulating agricultural practices. Nonetheless, in spite of these efforts, N will still be exported in large excess with respect to the equilibrium defined by the Redfield ratios, even in the most optimistic hypothesis describing the long-term response of groundwater nitrate concentrations. A comprehensive assessment of these mitigation measures supports the need for additional reductions of nutrient losses from agriculture to control harmful algae development. It also stresses the relevance of this mechanistic approach, in which nutrient transfers from land to sea can be calculated, as an integrated strategy to test policy recommendations.

  4. Strongly-sheared wind-forced currents in the nearshore regions of the central Southern California Bight

    Science.gov (United States)

    Noble, Marlene A.; Rosenberger, Kurt; Robertson, George L.

    2015-01-01

    Contrary to many previous reports, winds do drive currents along the shelf in the central portion of the Southern California Bight (SCB). Winds off Huntington Beach CA are the dominant forcing for currents over the nearshore region of the shelf (water depths less than 20 m). Winds control about 50–70% of the energy in nearshore alongshelf surface currents. The wind-driven current amplitudes are also anomalously high. For a relatively weak 1 dyne/cm2 wind stress, the alongshelf surface current amplitudes in this region can reach 80 cm/s or more. Mid-depth current amplitudes for the same wind stress are around 30–40 cm/s. These wind-driven surface current amplitudes are much larger than previously measured over other nearshore shelf regions, perhaps because this program is one of the few that measured currents within a meter of the surface. The near-bed cross-shelf currents over the nearshore region of the Huntington Beach shelf have an Ekman response to winds in that they upwell (downwell) for down (up) coast winds. This response disappears further offshore. Hence, there is upwelling in the SCB, but it does not occur across the entire shelf. Subthermocline water in the nearshore region that may contain nutrients and plankton move onshore when winds are southeastward, but subthermocline water over the shelf break is not transported to the beach. The currents over the outer shelf are not predominately controlled by winds, consistent with previous reports. Instead, they are mainly driven by cross-shelf pressure gradients that are independent of local wind stress.

  5. Algorithm Development and Validation for Satellite-Derived Distributions of DOC and CDOM in the US Middle Atlantic Bight

    Science.gov (United States)

    Mannino, Antonio; Russ, Mary E.; Hooker, Stanford B.

    2007-01-01

    In coastal ocean waters, distributions of dissolved organic carbon (DOC) and chromophoric dissolved organic matter (CDOM) vary seasonally and interannually due to multiple source inputs and removal processes. We conducted several oceanographic cruises within the continental margin of the U.S. Middle Atlantic Bight (MAB) to collect field measurements in order to develop algorithms to retrieve CDOM and DOC from NASA's MODIS-Aqua and SeaWiFS satellite sensors. In order to develop empirical algorithms for CDOM and DOC, we correlated the CDOM absorption coefficient (a(sub cdom)) with in situ radiometry (remote sensing reflectance, Rrs, band ratios) and then correlated DOC to Rrs band ratios through the CDOM to DOC relationships. Our validation analyses demonstrate successful retrieval of DOC and CDOM from coastal ocean waters using the MODIS-Aqua and SeaWiFS satellite sensors with mean absolute percent differences from field measurements of cdom)(355)1,6 % for a(sub cdom)(443), and 12% for the CDOM spectral slope. To our knowledge, the algorithms presented here represent the first validated algorithms for satellite retrieval of a(sub cdom) DOC, and CDOM spectral slope in the coastal ocean. The satellite-derived DOC and a(sub cdom) products demonstrate the seasonal net ecosystem production of DOC and photooxidation of CDOM from spring to fall. With accurate satellite retrievals of CDOM and DOC, we will be able to apply satellite observations to investigate interannual and decadal-scale variability in surface CDOM and DOC within continental margins and monitor impacts of climate change and anthropogenic activities on coastal ecosystems.

  6. Organic storage of CO/sub 2/ on the continental slope off the mid-Atlantic bight, the southeastern Bering Sea, and the Peru coast

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, J.J.; Premuzic, E.T.; Gaffney, J.S.; Rowe, G.T.; Harbottle, G.; Stoenner, R.W.; Balsam, W.L.; Betzer, P.R.; Macko, S.A.

    1985-01-01

    A comparison is made of organic content, sedimentation rates derived from /sup 14/C and /sup 210/Pb analyses, /sup 13/C and /sup 15/N isotope ratios, amorphous silica, particle size, and calcium carbonate within sediments from slopes off the mid-Atlantic bight, the southeastern Bering Sea, and the Peru coast. These sediments are mainly marine, diatom-rich, and about one-third of the organic carbon is recent, reflecting a possible transient of shelf export in response to man's increased activities since the industrial revolution. Using a combination of sedimentation and mixing rates of carbon, the C:N ratio of sediments within the upper 50 cm, and the amount of nitrogen thought to be released from the coastal zone, independent estimates suggest a carbon loading to world slopes of approx. 0.3 to 0.5 x 10/sup 9/ tons C y/sup -1/. The Bering slope exhibits no anthropogenic transients, however, while increased carbon loading may have occurred off Peru in response to overfishing and off the mid-Atlantic bight in response to eutrophication. The generality of their results depends on which of the three systems is most representative of world slopes.

  7. Continental slope sea level and flow variability induced by lateral movements of the Gulf Stream in the Middle Atlantic Bight

    Science.gov (United States)

    Böhm, E.; Hopkins, T. S.; Pietrafesa, L. J.; Churchill, J. H.

    2006-08-01

    As described by [Csanady, G.T., Hamilton, P., 1988. Circulation of slope water. Continental Shelf Research 8, 565-624], the flow regime over the slope of the southern Middle Atlantic Bight (MAB) includes a current reversal in which southwestward flow over the upper and middle slope becomes entrained in the northeastward current adjacent to the Gulf Stream. In this paper we use satellite-derived data to quantify how lateral motions of the Gulf Stream impact this current system. In our analysis, the Gulf Stream’s thermal front is delineated using a two-year time series of sea surface temperature derived from NOAA/AVHRR satellite data. Lateral motions of the Gulf Stream are represented in terms of temporal variations of the area, east of 73°W, between the Gulf Stream thermal front and the shelf edge. Variations of slope water flow within this area are represented by anomalies of geostrophic velocity as derived from the time series of the sea level anomaly determined from TOPEX/POSEIDON satellite altimeter data. A strong statistical relationship is found between Gulf Stream displacements and parabathic flow over the continental slope. It is such that the southwestward flow over the slope is accelerated when the Gulf Stream is relatively far from the shelf edge, and is decelerated (and perhaps even reversed) when the Gulf Stream is close to the shelf edge. This relationship between Gulf Stream displacements and parabathic flow is also observed in numerical simulations produced by the Miami Isopycnic Coordinate Model. In qualitative terms, it is consistent with the notion that when the Gulf Stream is closer to the 200-m isobath, it is capable of entraining a larger fraction of shelf water masses. Alternatively, when the Gulf Stream is far from the shelf-break, more water is advected into the MAB slope region from the northeast. Analysis of the diabathic flow indicates that much of the cross-slope transport by which the southwestward flow entering the study region is

  8. Temporal and spatial patterns in wind stress and wind stress curl over the central Southern California Bight

    Science.gov (United States)

    Noble, Marlene A.; Rosenberger, Kurt J.; Rosenfeld, Leslie K.; Robertson, George L.

    2012-01-01

    In 2001, the U.S. Geological Survey, together with several other federal and municipal agencies, began a series of field programs to determine along and cross-shelf transport patterns over the continental shelves in the central Southern California Bight. As a part of these programs, moorings that monitor winds were deployed off the Palos Verdes peninsula and within San Pedro Bay for six 3–4 month summer and winter periods between 2001 and 2008. In addition, nearly continuous records of winds for this 7-year period were obtained from a terrestrial site at the coast and from a basin site offshore of the long-term coastal site. The mean annual winds are downcoast at all sites. The alongshelf components of wind stress, which are the largest part of the low-frequency wind stress fields, are well correlated between basin, shelf and coastal sites. On average, the amplitude of alongshelf fluctuations in wind stress are 3–4 times larger over the offshore basin, compared to the coastal site, irrespective of whether the fluctuations represent the total, or just the correlated portion of the wind stress field. The curl in the large-scale wind stress tends to be positive, especially in the winter season when the mean wind stress is downcoast and larger at the offshore basin site than at the beach. However, since the fluctuation in wind stress amplitudes are usually larger than the mean, periods of weak negative curl do occur, especially in the summer season when the largest normalized differences in the amplitude of wind stress fluctuations are found in the nearshore region of the coastal ocean. Even though the low-frequency wind stress field is well-correlated over the continental shelf and offshore basins, out to distances of 35 km or more from the coast, winds even 10 km inshore of the beach do not represent the coastal wind field, at least in the summer months. The seasonal changes in the spatial structures in wind stress amplitudes suggest that an assessment of the

  9. Variability of carbon monoxide and carbon dioxide apparent quantum yield spectra in three coastal estuaries of the South Atlantic Bight

    Directory of Open Access Journals (Sweden)

    H. E. Reader

    2012-11-01

    Full Text Available The photochemical oxidation of oceanic dissolved organic carbon (DOC to carbon monoxide (CO and carbon dioxide (CO2 has been estimated to be a significant process with global photoproduction transforming petagrams of DOC to inorganic carbon annually. To further quantify the importance of these two photoproducts in coastal DOC cycling, 38 paired apparent quantum yield (AQY spectra for CO and CO2 were determined at three locations along the coast of Georgia, USA over the course of one year. The AQY spectra for CO2 were considerably more varied than CO. CO AQY spectra exhibited a seasonal shift in spectrally integrated (260 nm–490 nm AQY from higher efficiencies in the autumn to less efficient photoproduction in the summer. While full-spectrum photoproduction rates for both products showed positive correlation with pre-irradiation UV-B sample absorption (i.e. chromophoric dissolved organic matter, CDOM as expected, we found no correlation between AQY and CDOM for either product at any site. Molecular size, approximated with pre-irradiation spectral slope coefficients, and aromatic content, approximated by the specific ultraviolet absorption of the pre-irradiated samples, were also not correlated with AQY in either data set. The ratios of CO2 to CO photoproduction determined using both an AQY model and direct production comparisons were 23.2 ± 12.5 and 22.5 ± 9.0, respectively. Combined, both products represent a loss of 2.9 to 3.2% of the DOC delivered to the estuaries and inner shelf of the South Atlantic Bight yearly, and 6.4 to 7.3% of the total annual degassing of CO2 to the atmosphere. This result suggests that direct photochemical production of CO and CO2 is a small, yet significant contributor to both DOC cycling and CO2 gas exchange in this coastal system.

  10. Temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from FRANKLIN in the Great Australian Bight and Indian Ocean from 1994-11-12 to 1994-12-05 (NODC Accession 0116716)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0116716 includes chemical, discrete sample, physical and profile data collected from FRANKLIN in the Great Australian Bight and Indian Ocean from...

  11. Dissolved inorganic carbon, alkalinity, temperature, salinity and other variables collected from discrete sample and profile observations using CTD, bottle and other instruments from the AURORA AUSTRALIS in the Great Australian Bight and Indian Ocean from 1998-02-28 to 1998-04-01 (NODC Accession 0115154)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115154 includes chemical, discrete sample, physical and profile data collected from AURORA AUSTRALIS in the Great Australian Bight and Indian Ocean...

  12. Dissolved inorganic carbon, total alkalinity, nutrients, and other variables collected from profile and discrete observations using Niskin bottle and other instruments from NOAA Ship Henry B. Bigelow in Gulf of Maine, Georges Bank, and Mid-Atlantic Bight from 2015-05-20 to 2015-06-02 (NCEI Accession 0157024)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This archival package contains profile discrete measurements of dissolved inorganic carbon, total alkalinity, nutrients, and chlorophyll a in Mid-Atlantic Bight and...

  13. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from underway - surface observations using Barometric pressure sensor, Carbon dioxide (CO2) gas analyzer and other instruments from the AURORA AUSTRALIS in the Great Australian Bight, Indian Ocean and others from 1992-10-19 to 2001-12-12 (NODC Accession 0115153)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115153 includes chemical, meteorological, physical and underway - surface data collected from AURORA AUSTRALIS in the Great Australian Bight, Indian...

  14. Dissolved inorganic carbon, total alkalinity, pH, nutrients, and other variables collected from surface discrete observations using flow-through pump and other instruments from NOAA Ship Henry B. Bigelow on the Northeast U.S. Shelf (Gulf of Maine and Mid-Atlantic Bight) from 2013-03-17 to 2013-05-09 (NCEI Accession 0154386)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This archival package contains surface discrete measurements of dissolved inorganic carbon, total alkalinity, pH and nutrients in the Mid-Atlantic Bight and Gulf of...

  15. The Paternal Landscape along the Bight of Benin - Testing Regional Representativeness of West-African Population Samples Using Y-Chromosomal Markers.

    Directory of Open Access Journals (Sweden)

    Maarten H D Larmuseau

    Full Text Available Patterns of genetic variation in human populations across the African continent are still not well studied in comparison with Eurasia and America, despite the high genetic and cultural diversity among African populations. In population and forensic genetic studies a single sample is often used to represent a complete African region. In such a scenario, inappropriate sampling strategies and/or the use of local, isolated populations may bias interpretations and pose questions of representativeness at a macrogeographic-scale. The non-recombining region of the Y-chromosome (NRY has great potential to reveal the regional representation of a sample due to its powerful phylogeographic information content. An area poorly characterized for Y-chromosomal data is the West-African region along the Bight of Benin, despite its important history in the trans-Atlantic slave trade and its large number of ethnic groups, languages and lifestyles. In this study, Y-chromosomal haplotypes from four Beninese populations were determined and a global meta-analysis with available Y-SNP and Y-STR data from populations along the Bight of Benin and surrounding areas was performed. A thorough methodology was developed allowing comparison of population samples using Y-chromosomal lineage data based on different Y-SNP panels and phylogenies. Geographic proximity turned out to be the best predictor of genetic affinity between populations along the Bight of Benin. Nevertheless, based on Y-chromosomal data from the literature two population samples differed strongly from others from the same or neighbouring areas and are not regionally representative within large-scale studies. Furthermore, the analysis of the HapMap sample YRI of a Yoruban population from South-western Nigeria based on Y-SNPs and Y-STR data showed for the first time its regional representativeness, a result which is important for standard population and forensic genetic applications using the YRI sample

  16. Variabilidad mensual de la velocidad de surgencia y clorofila a en la región del Panama Bight (Monthly rate variation upwelling and chlorophyll a in the region of Panama Bight

    Directory of Open Access Journals (Sweden)

    Nancy Villegas

    2016-09-01

    Full Text Available Las zonas de surgencia y la presencia de clorofila a en la región del Panamá Bight (golfo de Panamá fueron comparadas en una escala mensual. Las variables utilizadas fueron la velocidad vertical de surgencia estimada mediante el software EVA. V.2.0 y la concentración de clorofila a obtenida de imágenes satelitales SeaWifs. El estudio fue realizado para el área costera entre 6° 30’ y 2° N y en los tres principales focos de ascenso de agua, el primero ubicado entre 83-84° W y 1° 30’-2° 30’ N, el segundo entre 81-82° W y 1° 30’-2° 30’ N, y el tercero entre 82-83° W y 2° 30’-3° 30’ N. Los resultados muestran la asociación directa entre la concentración de clorofila a y la surgencia durante todo el año. El estudio también resalta que el desplazamiento de la zona de convergencia intertropical ZCIT determina la variabilidad estacional del proceso de ascenso, atenuándolo cuando pasa sobre el área de estudio y reforzándolo mientras se aleja. El análisis de correlación entre las variables bajo estudio dio como resultado coeficientes estadísticamente significativos entre 0.5 y 0.9 en los tres focos principales y valores no significativos en la zona costera. (Abstract. The influence of the migration of the ITCZ on the climatic variability of the upwelling vertical velocity (Vz and the spatial-temporal behavior of upwelling spots over the CPO was determined. This influence was corroborated by the presence of chlorophyll a in the upwelling zones. Vz values were calculated with EVA . V.2.0 software. The chlorophyll a content was extracted from satellite images for 1997-2000. A comparison between the upwelling zones distribution, the migration of ITCZ and chlorophyll a was made. This comparison was based on the correlation between variables of three upwelling focuses and a coastal upwelling. The first focus was located between 83-84° W and 1° 30’-2° 30’ N, the second one between 81-82° W and 1° 30’- 2° 30

  17. Analysis of Thematic Mapper data for studying the suspended matter distribution in the coastal area of the German Bight (North Sea)

    Science.gov (United States)

    Doerffer, R.; Fischer, J.; Stoessel, M.; Brockmann, C.; Grassl, H.

    1989-01-01

    Thematic Mapper data were analyzed with respect to its capability for mapping the complex structure and dynamics of suspended matter distribution in the coastal area of the German Bight (North Sea). Three independent pieces of information were found by factor analysis of all seven TM channels: suspended matter concentration, atmospheric scattering, and sea surface temperature. For the required atmospheric correction, the signal-to-noise ratios of Channels 5 and 7 have to be improved by averaging over 25 x 25 pixels, which also makes it possible to monitor the aerosol optical depth and aerosol type over cloud-free water surfaces. Near-surface suspended matter concentrations may be detected with an accuracy of factor less than 2 by using an algorithm derived from radiative transfer model calculation. The patchiness of suspended matter and its relation to underwater topography was analyzed with autocorrelation and cross-correlation.

  18. Biogeochemical and Optical Analysis of Coastal DOM for Satellite Retrieval of Terrigenous DOM in the U.S. Middle Atlantic Bight

    Science.gov (United States)

    Mannino, A.; Dyda, R. Y.; Hernes, P. J.; Hooker, Stan; Hyde, Kim; Novak, Mike

    2012-01-01

    Estuaries and coastal ocean waters experience a high degree of variability in the composition and concentration of particulate and dissolved organic matter (DOM) as a consequence of riverine/estuarine fluxes of terrigenous DOM, sediments, detritus and nutrients into coastal waters and associated phytoplankton blooms. Our approach integrates biogeochemical measurements (elemental content, molecular analyses), optical properties (absorption) and remote sensing to examine terrestrial DOM contributions into the U.S. Middle Atlantic Bight (MAB). We measured lignin phenol composition, DOC and CDOM absorption within the Chesapeake and Delaware Bay mouths, plumes and adjacent coastal ocean waters to derive empirical relationships between CDOM and biogeochemical measurements for satellite remote sensing application. Lignin ranged from 0.03 to 6.6 ug/L between estuarine and outer shelf waters. Our results demonstrate that satellite-derived CDOM is useful as a tracer of terrigenous DOM in the coastal ocean

  19. Response patterns of phytoplankton growth to variations in resuspension in the German Bight revealed by daily MERIS data in 2003 and 2004

    Directory of Open Access Journals (Sweden)

    Jian Su

    2015-10-01

    Full Text Available Chlorophyll (chl a concentration in coastal seas exhibits variability on various spatial and temporal scales. Resuspension of particulate matter can somewhat limit algal growth, but can also enhance productivity because of the intrusion of nutrient-rich pore water from sediments or bottom water layers into the whole water column. This study investigates whether characteristic changes in net phytoplankton growth can be directly linked to resuspension events within the German Bight. Satellite-derived chl a were used to derive spatial patterns of net rates of chl a increase/decrease (NR in 2003 and 2004. Spatial correlations between NR and mean water column irradiance were analysed. High correlations in space and time were found in most areas of the German Bight (R2 > 0.4, suggesting a tight coupling between light availability and algal growth during spring. These correlations were reduced within a distinct zone in the transition between shallow coastal areas and deeper offshore waters. In summer and autumn, a mismatch was found between phytoplankton blooms (chl a > 6 mg m−3 and spring-tidal induced resuspension events as indicated by bottom velocity, suggesting that there is no phytoplankton resuspension during spring tides. It is instead proposed here that frequent and recurrent spring-tidal resuspension events enhance algal growth by supplying remineralized nutrients. This hypothesis is corroborated by a lag correlation analysis between resuspension events and in-situ measured nutrient concentrations. This study outlines seasonally different patterns in phytoplankton productivity in response to variations in resuspension, which can serve as a reference for modelling coastal ecosystem dynamics.

  20. Priceless prices and marine food webs: Long-term patterns of change and fishing impacts in the South Brazil Bight as reflected by the seafood market

    Science.gov (United States)

    Pincinato, R. B. M.; Gasalla, M. A.

    2010-10-01

    The lack of market variables in fishery systems (i.e., prices and quantities) has often been cited as one reason for the particular difficulty of understanding whole marine ecosystem change and its management under a broader ecosystem perspective. This paper shows the results of efforts to tackle this problem in the South Brazil Bight by compiling and analyzing in-depth an unprecedented 40-year database from the region’s largest wholesale seafood market, based in the megacity of São Paulo. Fishery landings and market values for the period 1968-2007 were analyzed primarily by updated trophic level classes and multispecies indicators including the (1) marine trophic index (MTI), (2) weighted price, and (3) log relative price index (LRPI) which relates prices and trophic levels. Moreover, an inferential analysis of major seafood category statistical trends in market prices and quantities and their positive and negative correlations was undertaken. In general, these market trends contributed substantially to identifying and clarifying the changes that occurred. Considerations of the behavior of demand, supply and markets are included. In particular, while the MTI did not support a “fishing down the marine food web” hypothesis, other indicators did show the continued scarcity of major high trophic level categories and fisheries target species. Overall, the results indicate that the analysis of fishery landings, or of certain other indicators alone, can mask real changes. Rather, a joint ecological-econometric analysis provides better evidence of the direction of ecosystem pressures and stock health. This method for detecting market changes across the food web may be particularly helpful for systems considered data-poor but where fish market data have been archived. This study further elucidates historical changes and fishing impacts in the South Brazil Bight ecosystem.

  1. Applicability of a numerical model to predict vertical distribution of suspended sediment concentration along the depth in Dithmarschen Bight

    Science.gov (United States)

    Rahbani, M.

    2012-04-01

    A three dimensional numerical model of Delft3d-flow was developed to simulate the current velocity and sediment transport of Piep tidal channel system. This channel system is part of Dithmarschen Bight located in the German North Sea coast. It consists of two main channel namely Norderpiep, and Süderpiep. These two channels conjunct together to form Piep channel near the land on tidal flat. The source of the required field data for this study was those collected under "Prediction of Medium Term Coastal Morphodynamics", known as the PROMORPH project. It was executed during the period May 1999 to June 2002. Those measured data used for calibration and validation of the model were current velocity and suspended sediment concentration (SSC). Current velocities were collected using ADCP devise. Suspended sediment concentration data was prepared by converting the measured values of light transmission. These data was collected using transmissometer. On the basis of some in situ mechanical sampler data an equation was developed to convert light transmission to the SSC. Field data were carried out at several stations along the width of three cross sections from the surface to the bottom, taking into account the limitations. To verify the performance of the calibrated model, its results were compared with the field data. The comparison between the modeled and measured current velocity shows an accuracy of about 0.2 m/s. Factor of two of measured SSC were used to evaluate the performance of the model regarding these values. Some dissimilarity was found between the modeled SSC and those of the field data.To verify the cause of this dissimilarity, two comparing procedures were carried out. First the evolution of the vertical profile of the SSC from the model and those from the field were prepared and compared. In another procedure the snapshot of distribution of SSC at each cross section during different phases of a tidal cycle were prepared using the model results and

  2. Carbon, nitrogen and phosphorus dynamics in nine sub-systems of the Sylt-Rømø Bight ecosystem, German Wadden Sea

    Science.gov (United States)

    Baird, Dan; Asmus, Harald; Asmus, Ragnhild

    2011-01-01

    Flow networks of nine sub-systems consisting of 59 components each of the Sylt-Rømø Bight, German Wadden Sea, were constructed depicting the standing stocks and flows of material and energy within and between the sub-systems. Carbon, nitrogen and phosphorous were used as currencies for each sub-system, thus resulting in 27 network models, which were analyzed by ecological network analytical protocols. Results show substantial variability in the dynamics of these elements within and between the nine sub-systems, which differ in habitat structure, species diversity and in the standing stocks of their constituent living and non-living components. The relationship between the biodiversity and selected information indices and ratios, derived from ecological network analysis, of individual sub-systems is variable and differ substantially between them. Ecosystem properties such as the structure and magnitude of the recycling of these elements, number of cycles, and total sub-system activity were calculated and discussed, highlighting the differences between and complexity of the flow of C, N and P in a coastal marine ecosystem. The average number of cycles increase from 179 for C, to 16,923 and 20,580 for N and P respectively, while the average amount of recycled material, as measured by the Finn Cycling Index (FCI), increase from 17% for C, to 52% for P and to 61% for N. The number of cycles and the FCI vary considerably between the sub-systems for the different elements. The largest number of cycles of all three elements was observed in the muddy sand flat sub-system, but the highest FCIs were computed for both C (32%) and N (85%) in the Arenicola Flats, and in sparse Zostera noltii sea grass beds for P (67%). Indices reflecting on the growth, organization and resilience of the sub-systems also showed considerable variability between and within the inter-tidal ecosystems in the Bight. Indices such as, for example, the relative ascendency ratios increase on average

  3. Operational wave now- and forecast in the German Bight as a basis for the assessment of wave-induced hydrodynamic loads on coastal dikes

    Science.gov (United States)

    Dreier, Norman; Fröhle, Peter

    2017-12-01

    The knowledge of the wave-induced hydrodynamic loads on coastal dikes including their temporal and spatial resolution on the dike in combination with actual water levels is of crucial importance of any risk-based early warning system. As a basis for the assessment of the wave-induced hydrodynamic loads, an operational wave now- and forecast system is set up that consists of i) available field measurements from the federal and local authorities and ii) data from numerical simulation of waves in the German Bight using the SWAN wave model. In this study, results of the hindcast of deep water wave conditions during the winter storm on 5-6 December, 2013 (German name `Xaver') are shown and compared with available measurements. Moreover field measurements of wave run-up from the local authorities at a sea dike on the German North Sea Island of Pellworm are presented and compared against calculated wave run-up using the EurOtop (2016) approach.

  4. Assessing the Roles of Iron, Macronutrients and Wet deposition in Controlling Phytoplankton Growth in Seasonally Oligotrophic Waters of the Mid-Atlantic Bight

    Science.gov (United States)

    Sedwick, P.; Mulholland, M. R.; Najjar, R.; Bernhardt, P. W.; Price, L. M.; Sohst, B. M.; Sookhdeo, C.; Widner, B.

    2016-02-01

    The role of iron supply in regulating phytoplankton production in high-nutrient, low-chlorophyll ocean regions has been well established. Less clear, however, is the importance of iron for phytoplankton processes in other oceanic settings, such as coastal and oligotrophic waters, where differential changes in the supply and removal of dissolved iron (dFe) can result in limitation or co-limitation of growth due to iron deficiency. One such region of interest is the Mid-Atlantic Bight (MAB), where previous field experiments have provided some evidence of co-limitation of algal growth by nitrogen and iron. In summer 2014 we conducted field sampling and shipboard experiments to assess the role of iron and macronutrient availability in controlling primary production in seasonally oligotrophic waters over the MAB continental slope, with a focus on the the impacts of wet deposition. Our results indicate that nitrogen was the proximate limiting nutrient, with a secondary limitation imposed by availability of phosphorus; we found no evidence for a deficiency in dFe, which was present at concentrations in the range 0.3-0.9 nM. Phytoplankton growth was clearly stimulated by the addition of natural rainwater, suggesting that summer rain events stimulate primary production in the MAB by contributing new nitrogen (primarily as ammonium) and phosphorus, whilst maintaining iron-replete conditions.

  5. Seasonality and flux estimates of dissolved organic carbon in tidal wetlands and estuaries in the U.S. Mid- Atlantic Bight and Gulf of Mexico from ocean color

    Science.gov (United States)

    Cao, F.; Tzortziou, M.; Hu, C.; Najjar, R.

    2016-02-01

    Tidal wetlands and estuaries are dynamic features of coastal ocean and play critical roles in the global carbon cycle. Exchanges of dissolved organic carbon (DOC) between tidal wetlands and adjacent estuaries have important implications for carbon sequestration in tidal wetlands as well as biogeochemical cycling of wetlands derived material in the coastal zones. Recent studies demonstrated that the absorption coefficients of chromophoric dissolved organic matter at λ= 275 and 295 nm, which can be derived from satellite ocean color observations, can be used to accurately retrieve dissolved organic carbon (DOC) in some coastal waters. Based on a synthesis of existing field observations collected covering wide spatial and temporal variability in the Mid-Atlantic Bight and the Gulf of Mexico, here we developed and validated new empirical models to estimate coastal DOC from remotely sensed bio-optical properties of the surface water. We focused on the interfaces between tidal wetland-estuary and estuary-shelf water domains. The DOC algorithms were applied to SeaWiFs and MODIS observations to generate long-term climatological DOC distributions from 1998 to 2014. Empirical orthogonal function analysis revealed strong seasonality and spatial gradients in the satellite retrieved DOC in the tidal wetlands and estuaries. Combined with field observations and biogeochemical models, satellite retrievals can be used to scale up carbon fluxes from individual marshes and sub-estuaries to the whole estuarine system, and improve understanding of biogeochemical exchanges between terrestrial and aquatic ecosystems.

  6. Numerical simulations for the area of the German Bight in spring 1995; Numerische Simulationsrechnungen fuer das Gebiet der Deutschen Bucht am Beispiel des Fruehjahrs 1995

    Energy Technology Data Exchange (ETDEWEB)

    Lenz, C.J. [Hamburg Univ. (Germany). Meteorologisches Inst.

    1998-01-01

    The paper reports results of the mesoscale transport, chemism and flow model METRAS for the period from 22 April to 11 May 1995. During this period, a measurement campaign was carried out in the area of the German Bight under the ``KUSTOS`` springtime scheme (``Coastal mass and energy transport processes - The transition from land to sea in the south-eastern North Sea``). In order to take instationary and inhomogeneous weather situations into account, the modellings used data provided by the German weather service, which form part of its Germany model (DM), both to initialize and drive the METRAS data. The modelling results of METRAS are compared with routine readings taken by the German weather service in some selected measuring sites. (orig./KW) [Deutsch] In diesem Beitrag werden Ergebnisse des mesoskaligen Transport-, Chemie- und Stroemungsmodells METRAS fuer den Zeitraum vom 22. April bis zum 11. Mai 1995 vorgestellt, in dem die Messkampagne des KUSTOS-Fruehjahrsexperimentes (Kuestennahe Stoff- und Energietransporte - der Uebergang Land - Meer in der suedoestlichen Nordsee) im Bereich der Deutschen Bucht stattfand. Zur Beruecksichtigung instationaerer und inhomogener Wetterlagen bei den Modellrechnungen wurden sowohl zur Initialisierung als auch zum Antrieb von METRAS Daten des Deutschland-Modells (DM) des Deutschen Wetterdienstes verwendet. Die Modellergebnisse von METRAS werden mit Routinemessungen des Deutschen Wetterdienstes an einigen ausgewaehlten Messstationen verglichen. (orig./KW)

  7. On the dynamics of compound bedforms in high-energy tidal channels: field observations in the German Bight and the Danish Wadden Sea

    Science.gov (United States)

    Ernstsen, Verner B.; Winter, Christian; Becker, Marius; Bartholdy, Jesper

    2010-05-01

    Tidal inlets are a common feature along much of the world's coastlines. They interrupt the alongshore continuity of shoreline processes, and by being exposed to both wave and current forcing, tidal inlets belong to the morphologically most dynamic and complex coastal systems on Earth. The tidal channels in these inlets are characterized by high flow velocities and, accordingly, the channel beds are typically sandy and covered with bedforms. The bedform fields in nature are often complex systems with larger primary-bedforms superimposed by smaller secondary-bedforms (cf. Bartholdy et al., 2002). There is a considerable amount of detailed field investigations on the dynamics of primary-bedforms at various temporal scales, ranging from short- to long-term tide-related cycles to flood hydrographs to seasonality. However, Julien et al. (2002) stated that a composite analysis of primary- and secondary-bedforms is recommended for future studies on resistance to flow. Such knowledge on the behaviour of compound bedforms is still deficient. In this study, we combine the findings on the dynamics of primary- and secondary-bedform height from detailed field investigations carried out in two high-energy tidal channels during 2007 and 2008: the Knudedyb tidal inlet channel in the Danish Wadden Sea and the Innenjade tidal channel in the Jade Bay, German Bight (both survey areas being ebb-dominated). We provide process-based explanations of the bedform behaviour and present a conceptual model of compound bedform dynamics. The conducted field investigations comprised repetitive, simultaneous measurements of high-resolution swath bathymetry (using a multibeam echosounder system) and flow velocity (using an acoustic Doppler current profiler) in combination with detailed spatial mapping of bed material characteristics (from grab sampling of bed material). For an objective and discrete analysis of primary- and secondary-bedforms a modified version of the bedform tracking tool

  8. Combined analysis of field and model data: A case study of the phosphate dynamics in the German Bight in summer 1994

    Science.gov (United States)

    Pohlmann, Th.; Raabe, Th.; Doerffer, R.; Beddig, S.; Brockmann, U.; Dick, S.; Engel, M.; Hesse, K.-J.; König, P.; Mayer, B.; Moll, A.; Murphy, D.; Puls, W.; Rick, H.-J.; Schmidt-Nia, R.; Schönfeld, W.; Sündermann, J.

    1999-09-01

    The intention of this paper is to analyse a specific phenomenon observed during the KUSTOS campaigns in order to demonstrate the general capability of the KUSTOS and TRANSWATT approach, i.e. the combination of field and modelling activities in an interdisciplinary framework. The selected phenomenon is the increase in phosphate concentrations off the peninsula of Eiderstedt on the North Frisian coast sampled during four subsequent station grids of the KUSTOS summer campaign in 1994. First of all, a characterisation of the observed summer situation is given. The phosphate increase is described in detail in relation to the dynamics of other nutrients. In a second step, a first-order estimate of the dispersion of phosphate is discussed. The estimate is based on the box model approach and will focus on the effects of the river Elbe and Wadden Sea inputs on phosphate dynamics. Thirdly, a fully three-dimensional model system is presented, which was implemented in order to analyse the phosphate development. The model system is discussed briefly, with emphasis on phosphorus-related processes. The reliability of one of the model components, i.e. the hydrodynamical model, is demonstrated by means of a comparison of model results with observed current data. Thereafter, results of the German Bight seston model are employed to interpret the observed phosphate increase. From this combined analysis, it was possible to conclude that the phosphate increase during the first three surveys was due to internal transformation processes within the phosphorus cycle. On the other hand, the higher phosphate concentrations measured in the last station grid survey were caused by a horizontal transport of phosphate being remobilised in the Wadden Sea.

  9. Molecular Gut Content Profiling to Investigate the In Situ Grazing and Selectivity of Dolioletta gegenbauri in Summer Continental Shelf Intrusion Waters of the South Atlantic Bight, USA

    Science.gov (United States)

    Walters, T. L.; Frazier, L.; Gibson, D. M.; Paffenhofer, G. A.; Frischer, M. E.

    2016-02-01

    Gelatinous metazooplankton play a crucial role in marine planktonic food webs and it has been suggested that they may become increasingly important in the Future Ocean. However, largely due to methodological challenges and reliance on laboratory cultivation approaches, the in situ diet of zooplankton with complex life histories and diverse prey choices remains poorly investigated. This is particularly true for the gelatinous zooplankton including the pelagic tunicate, Dolioletta gegenbauri that form large blooms in productive subtropical continental shelf environments. To investigate the diet of D. gegenbauri we developed a molecular gut profiling approach based on the use of a Peptide Nucleic Acid (PNA) PCR blocker. Using a doliolid-specific PNA blocker, it was possible to enrich the amplification of prey and parasite DNA from whole animal DNA extracts of doliolids. Gut contents from the water column, wild and captive-fed doliolids were profiled after PNA-PCR by denaturing HPLC (dHPLC), clone library and next generation sequencing (NGS) approaches. Studies were conducted during 5 summer cruises in the mid-shelf of the South Atlantic Bight. Comparison of gut profiles to available prey in the water column revealed evidence of prey selection towards larger prey species, including diatoms, dinoflagelletes and also metazoan prey that were likely captured as larvae and eggs. Wild-caught doliolids contained significantly more metazoan sequences than did the captive-fed doliolids. Ingestion of metazoan prey suggests that metazoans may contribute both the nutrition of doliolids and the potential role of doliolids as trophic cascade agents in continental shelf pelagic food webs.

  10. The role of remote wind forcing in the subinertial current variability in the central and northern parts of the South Brazil Bight

    Science.gov (United States)

    Dottori, Marcelo; Castro, Belmiro Mendes

    2018-05-01

    Data analysis of continental shelf currents and coastal sea level, together with the application of a semi-analytical model, are used to estimate the importance of remote wind forcing on the subinertial variability of the current in the central and northern areas of the South Brazil Bight. Results from both the data analysis and from the semi-analytical model are robust in showing subinertial variability that propagates along-shelf leaving the coast to the left in accordance with theoretical studies of Continental Shelf Waves (CSW). Both the subinertial variability observed in along-shelf currents and sea level oscillations present different propagation speeds for the narrow northern part of the SBB ( 6-7 m/s) and the wide central SBB region ( 11 m/s), those estimates being in agreement with the modeled CSW propagation speed. On the inner and middle shelf, observed along-shelf subinertial currents show higher correlation coefficients with the winds located southward and earlier in time than with the local wind at the current meter mooring position and at the time of measurement. The inclusion of the remote (located southwestward) wind forcing improves the prediction of the subinertial currents when compared to the currents forced only by the local wind, since the along-shelf-modeled currents present correlation coefficients with observed along-shelf currents up to 20% higher on the inner and middle shelf when the remote wind is included. For most of the outer shelf, on the other hand, this is not observed since usually, the correlation between the currents and the synoptic winds is not statistically significant.

  11. Downscaling, 2-way Nesting, and Data Assimilative Modeling in Coastal and Shelf Waters of the U.S. Mid-Atlantic Bight and Gulf of Maine

    Science.gov (United States)

    Wilkin, J.; Levin, J.; Lopez, A.; Arango, H.

    2016-02-01

    Coastal ocean models that downscale output from basin and global scale models are widely used to study regional circulation at enhanced resolution and locally important ecosystem, biogeochemical, and geomorphologic processes. When operated as now-cast or forecast systems, these models offer predictions that assist decision-making for numerous maritime applications. We describe such a system for shelf waters of the Mid-Atlantic Bight (MAB) and Gulf of Maine (GoM) where the MARACOOS and NERACOOS associations of U.S. IOOS operate coastal ocean observing systems that deliver a dense observation set using CODAR HF-radar, autonomous underwater glider vehicles (AUGV), telemetering moorings, and drifting buoys. Other U.S. national and global observing systems deliver further sustained observations from moorings, ships, profiling floats, and a constellation of satellites. Our MAB and GoM re-analysis and forecast system uses the Regional Ocean Modeling System (ROMS; myroms.org) with 4-dimensional Variational (4D-Var) data assimilation to adjust initial conditions, boundary conditions, and surface forcing in each analysis cycle. Data routinely assimilated include CODAR velocities, altimeter satellite sea surface height (with coastal corrections), satellite temperature, in situ CTD data from AUGV and ships (NMFS Ecosystem Monitoring voyages), and all in situ data reported via the WMO GTS network. A climatological data assimilative analysis of hydrographic and long-term mean velocity observations specifies the regional Mean Dynamic Topography that augments altimeter sea level anomaly data and is also used to adjust boundary condition biases that would otherwise be introduced in the process of downscaling from global models. System performance is described with respect to the impact of satellite, CODAR and in situ observations on analysis skill. Results from a 2-way nested modeling system that adds enhanced resolution over the NSF OOI Pioneer Array in the central MAB are also

  12. A numerical analysis of shipboard and coastal zone color scanner time series of new production within Gulf Stream cyclonic eddies in the South Atlantic Bight

    Science.gov (United States)

    Pribble, J. Raymond; Walsh, John J.; Dieterle, Dwight A.; Mueller-Karger, Frank E.

    1994-01-01

    Eddy-induced upwelling occurs along the western edge of the Gulf Stream between Cape Canaveral, Florida, and Cape Hatteras, North Carolina, in the South Atlantic Bight (SAB). Coastal zone color scanner images of 1-km resolution spanning the period April 13-21, 1979, were processed to examine these eddy features in relation to concurrent shipboard and current/temperature measurements at moored arrays. A quasi-one-dimensional (z), time dependent biological model, using only nitrate as a nutrient source, has been combined with a three-dimensional physical model in an attempt to replicate the observed phytoplankton field at the northward edge of an eddy. The model is applicable only to the SAB south of the Charleston Bump, at approximately 31.5 deg N, since no feature analogous to the bump exists in the model bathymetry. The modeled chlorophyll, nitrate, and primary production fields of the euphotic zone are very similar to those obtained from the satellite and shipboard data at the leading edges of the observed eddies south of the Charleston Bump. The horizontal and vertical simulated fluxes of nitrate and chlorophyll show that only approximately 10% of the upwelled nitrate is utilized by the phytoplankton of the modeled grid box on the northern edge of the cyclone, while approximately 75% is lost horizontally, with the remainder still in the euphotic zone after the 10-day period of the model. Loss of chlorophyll due to sinking is very small in this strong upwelling region of the cyclone. The model is relatively insensitive to variations in the sinking parameterization and the external nitrate and chlorophyll fields but is very sensitive to a reduction of the maximum potential growth rate to half that measured. Given the success of this model in simulating the new production of the selcted upwelling region, other upwelling regions for which measurements or successful models of physical and biological quantities and rates exist could be modeled similarly.

  13. Body growth and reproduction of individuals of the sciaenid fish Stellifer rastrifer in a shallow tropical bight: A cautionary tale for assumptions regarding population parameters

    Science.gov (United States)

    Pombo, Maíra; Denadai, Márcia Regina; Turra, Alexander

    2013-05-01

    Knowledge of population parameters and the ability to predict their responses to environmental changes are useful tools to aid in the appropriate management and conservation of natural resources. Samples of the sciaenid fish Stellifer rastrifer were taken from August 2003 through October 2004 in shallow areas of Caraguatatuba Bight, southeastern Brazil. The results showed a consistent presence of length-frequency classes throughout the year and low values of the gonadosomatic index of this species, indicating that the area is not used for spawning or residence of adults, but rather shelters individuals in late stages of development. The results may serve as a caveat for assessments of transitional areas such as the present one, the nursery function of which is neglected compared to estuaries and mangroves. The danger of mismanaging these areas by not considering their peculiarities is emphasized by using these data as a study case for the development of some broadly used population-parameter analyses. The individuals' body growth parameters from the von Bertalanffy model were estimated based on the most common approaches, and the best values obtained from traditional quantification methods of selection were very prone to bias. The low gonadosomatic index (GSI) estimated during the period was an important factor in stimulating us to select more reliable parameters of body growth (L∞ = 20.9, K = 0.37 and Z = 2.81), which were estimated based on assuming the existence of spatial segregation by size. The data obtained suggest that the estimated mortality rate included a high rate of migration of older individuals to deeper areas, where we assume that they completed their development.

  14. Highly dynamic biological seabed alterations revealed by side scan sonar tracking of Lanice conchilega beds offshore the island of Sylt (German Bight)

    Science.gov (United States)

    Heinrich, C.; Feldens, P.; Schwarzer, K.

    2017-06-01

    Hydroacoustic surveys are common tools for habitat investigation and monitoring that aid in the realisation of the aims of the EU Marine Directives. However, the creation of habitat maps is difficult, especially when benthic organisms densely populate the seafloor. This study assesses the sensitivity of entropy and homogeneity image texture parameters derived from backscatter strength data to benthic habitats dominated by the tubeworm Lanice conchilega. Side scan sonar backscatter surveys were carried out in 2010 and 2011 in the German Bight (southern North Sea) at two sites approx. 20 km offshore of the island of Sylt. Abiotic and biotic seabed facies, such as sorted bedforms, areas of fine to medium sand and L. conchilega beds with different tube densities, were identified and characterised based on manual expert analysis and image texture analysis. Ground truthing was performed by grab sampling and underwater video observations. Compared to the manual expert analysis, the k- means classification of image textures proves to be a semi-automated method to investigate small-scale differences in a biologically altered seabed from backscatter data. The texture parameters entropy and homogeneity appear linearly interrelated with tube density, the former positively and the latter negatively. Reinvestigation of one site after 1 year showed an extensive change in the distribution of the L. conchilega-altered seabed. Such marked annual fluctuations in L. conchilega tube cover demonstrate the need for dense time series and high spatial coverage to meaningfully monitor ecological patterns on the seafloor with acoustic backscatter methods in the study region and similar settings worldwide, particularly because the sand mason plays a pivotal role in promoting biodiversity. In this context, image texture analysis provides a cost-effective and reproducible method to track biologically altered seabeds from side scan sonar backscatter signatures.

  15. Sex-ratio, seasonality and long-term variation in maturation and spawning of the brown shrimp Crangon crangon (L.) in the German Bight (North Sea)

    Science.gov (United States)

    Siegel, V.; Damm, U.; Neudecker, T.

    2008-12-01

    Aspects of the reproductive and maturation biology of the brown shrimp Crangon crangon (L.) were studied in various subareas of the German Bight (North Sea). The size-specific sex ratio of C. crangon was examined based on length frequency distribution data. The sex ratio for the smallest size groups at which sex was determined was typically around 0.5, indicating an even ratio between males and females. The proportion of females decreased in the 30-45 mm size range. In length classes larger than 50 mm, the proportion of females constantly increases to 100% at around 60 mm total length. We concluded that sex reversal from male to female may not occur in C. crangon. Size at sexual maturity was determined from the proportion of ovigerous females. Size at maturity ( L 50) was estimated as 55.4 and 62.0 mm total length for spring and winter data, respectively. The seasonal spawning cycle was studied over the period 1958-2005. Between mid February and late June and for size classes larger than 65 mm ovigerous shrimps exceeded 80% and reached up to 100% of the females in the population. This period can be seen as the core spawning season. From early August to early December the proportion of ovigerous shrimps in the female population is very low. Interannual differences in the seasonal process are obvious with a dramatic decline in C. crangon reproductive success in the late 1980s. Various options are discussed for the reasons of the decline and recovery of the reproductive performance.

  16. Parasites of the flounder Platichthys flesus (L.) from the German Bight, North Sea, and their potential use in ecosystem monitoring. A. Infection characteristics of potential indicator species

    Science.gov (United States)

    Schmidt, V.; Zander, S.; Körting, W.; Steinhagen, D.

    2003-10-01

    As part of integrated biological-effect monitoring, the parasite fauna of the flounder Platichthys flesus (L.) was investigated at five locations in the German Bight, with a view to using parasite species as bio-indicators. Over a period of 6 years, parasites from 30 different taxa were identified, but only 7 taxa of the parasite community occurred regularly at all locations and in sufficient abundance that they could be considered as potential indicator species. These species were the ciliophoran Trichodina spp., the copepods Acanthochondria cornuta, Lepeophtheirus pectoralis and Lernaeocera branchialis, the helminths Zoogonoides viviparus and Cucullanus heterochrous and metacercaria of an unidentified digenean species. Infection characteristics of these parasites are presented, with a comparison of the results from individual sampling periods and those of the long-term data set. Natural influences on the infection levels, such as temporal variations, habitat conditions and host-related factors, were evaluated. All of these parasite species showed significant differences in their infection levels between the Elbe estuary, as the most polluted site, and the less polluted coastal and marine locations: Helgoland, Outer Eider estuary and Spiekeroog, especially in the long-term data set. Gradual differences between the Elbe, the Outer Eider and Helgoland, which were not detected in individual sampling periods, also became evident in the pooled-data set. These were found in the prevalence of Trichodina spp., A. cornuta, Z. viviparus and C. heterochrous. Although salinity is considered as the most important natural factor, influencing the distribution pattern of the majority of the potential indicator species, infection levels of most of these species differed between locations with similar salinity conditions. Infection levels corresponded to a contamination gradient (Elbe > Inner Eider, Outer Eider > Helgoland) established across the locations. Seasonal variation in

  17. Carbon dynamics and CO2 air-sea exchanges in the eutrophied coastal waters of the Southern Bight of the North Sea: a modelling study

    Directory of Open Access Journals (Sweden)

    N. Gypens

    2004-01-01

    Full Text Available A description of the carbonate system has been incorporated in the MIRO biogeochemical model to investigate the contribution of diatom and Phaeocystis blooms to the seasonal dynamics of air-sea CO2 exchanges in the Eastern Channel and Southern Bight of the North Sea, with focus on the eutrophied Belgian coastal waters. For this application, the model was implemented in a simplified three-box representation of the hydrodynamics with the open ocean boundary box ‘Western English Channel’ (WCH and the ‘French Coastal Zone’ (FCZ and ‘Belgian Coastal Zone’ (BCZ boxes receiving carbon and nutrients from the rivers Seine and Scheldt, respectively. Results were obtained by running the model for the 1996–1999 period. The simulated partial pressures of CO2 (pCO2 were successfully compared with data recorded over the same period in the central BCZ at station 330 (51°26.05′ N; 002°48.50′ E. Budget calculations based on model simulations of carbon flow rates indicated for BCZ a low annual sink of atmospheric CO2 (−0.17 mol C m-2 y-1. On the opposite, surface water pCO2 in WCH was estimated to be at annual equilibrium with respect to atmospheric CO2. The relative contribution of biological, chemical and physical processes to the modelled seasonal variability of pCO2 in BCZ was further explored by running model scenarios with separate closures of biological activities and/or river inputs of carbon. The suppression of biological processes reversed direction of the CO2 flux in BCZ that became, on an annual scale, a significant source for atmospheric CO2 (+0.53 mol C m-2 y-1. Overall biological activity had a stronger influence on the modelled seasonal cycle of pCO2 than temperature. Especially Phaeocystis colonies which growth in spring were associated with an important sink of atmospheric CO2 that counteracted the temperature-driven increase of pCO2 at this period of the year. However, river inputs of organic and inorganic carbon were

  18. A new 0.9 Ma oxygen isotope stratigraphy for a shallow-water sedimentary transect across three IODP 317 sites in the Canterbury Bight of southwest Pacific Ocean

    Science.gov (United States)

    Ding, Xuan; Wu, YingYing

    2016-04-01

    Sedimentary records in shallow-water environment provide unique opportunity to further our understanding on the regional relative sea level changes in relation to global climate change. Here we present a new 0.9 Ma oxygen isotope stratigraphy for a shallow-water sedimentary transect across three IODP 317 sites in the Canterbury Bight of southwest Pacific Ocean. The three sites are located on the eastern margin of the South Island of New Zealand, including a continental slope site, IODP317-U1352 and two continental shelf sites, IODP317-U1354 and IODP317-U1351. We first generated high resolution benthic foraminifers (Nonionella flemingi) δ18O records for the three sites and a planktonic (Globigerina bulloides) record for the U1352B. An initial chronological framework for the benthic δ18O record of the U1352B was constructed using 8 accelerator mass spectrometry (AMS) radiocarbon dates and 4 biostratigraphic events. Then a refined age model was established by correlating the U1352B benthic δ18O record with the EDC δD record on the AICC2012 time-scale, and the LR04 benthic δ18O stack. Although the U1354B and U1351B have lower sedimentation rates, their benthic δ18O records correlate well with that of U1352B. In order to ensure the accuracy of the chronostratigraphic framework established, we also analyzed the characteristics of sedimentary grain size and the planktonic and benthic δ18O values. In accord with the adjacent sites, the results show that the melt of Southern Alps glaciers due to the warming climate during MIS 11 and 5.5 led to the increased fresh water delivery, with massive terrigenous deposit; and the warm SST during the MIS7 is related with the STF migration, which led to strong current activity, with coarser grain size. Meanwhile, records of benthic δ18O, sedimentation rate and content of >63μm coarse fraction of site U1352 all indicate the MIS 20 was indeed a colder interval compared to subsequent glacial times.

  19. Isotopic evidence for dead fish maintenance of Florida red tides, with implications for coastal fisheries over both source regions of the West Florida shelf and within downstream waters of the South Atlantic Bight

    Science.gov (United States)

    Walsh, J. J.; Weisberg, R. H.; Lenes, J. M.; Chen, F. R.; Dieterle, D. A.; Zheng, L.; Carder, K. L.; Vargo, G. A.; Havens, J. A.; Peebles, E.; Hollander, D. J.; He, R.; Heil, C. A.; Mahmoudi, B.; Landsberg, J. H.

    2009-01-01

    Toxic Florida red tides of the dinoflagellate Kareniabrevis have downstream consequences of 500-1000 km spatial extent. Fish stocks, shellfish beds, and harmful algal blooms of similar species occupy the same continental shelf waters of the southeastern United States, amounting to economic losses of more than 25 million dollars in some years. Under the aegis of the Center for Prediction of Red tides, we are now developing coupled biophysical models of the conditions that lead to red tides and impacted coastal fisheries, from the Florida Panhandle to Cape Hatteras. Here, a nitrogen isotope budget of the coastal food web of the West Florida shelf (WFS) and the downstream South Atlantic Bight (SAB) reaffirms that diazotrophs are the initial nutrient source for onset of red tides and now identifies clupeid fish as the major recycled nutrient source for their maintenance. The recent isotope budget of WFS and SAB coastal waters during 1998-2001 indicates that since prehistoric times of Timacua Indian settlements along the Georgia coast during 1075, ∼50% of the nutrients required for large red tides of >1 μg chl l -1 of K.brevis have been derived from nitrogen-fixers, with the other half from decomposing dead sardines and herrings. During 2001, >90% of the harvest of WFS clupeids was by large ichthyotoxic red tides of >10 μg chl l -1 of K.brevis, rather than by fishermen. After onset of the usual red tides in summer of 2006 and 2007, the simulated subsequent fall exports of Florida red tides in September 2007 to North Carolina shelf waters replicate observations of just ∼1 μg chl l -1 on the WFS that year. In contrast, the earlier red tides of >10 μg chl l -1 left behind off West Florida during 2006, with less physical export, are instead 10-fold larger than those of 2007. Earlier, 55 fish kills were associated with these coastal red tides during September 2006, between Tampa and Naples. Yet, only six fish kills were reported there in September 2007. With little

  20. Task 1: Whole-body concentrations of elements in kelp bass (Paralabrax clathratus), kelp rockfish (Sebastes atrovirens), and Pacific sanddab (Citharichthys sordidus) from offshore oil platforms and natural areas in the Southern California Bight

    Science.gov (United States)

    Love, Milton S.

    2009-01-01

    Resource managers are concerned that offshore oil platforms in the Southern California Bight may be contributing to environmental contaminants accumulated by marine fishes. To examine this possibility, 18 kelp bass (Paralabrax clathratus), 80 kelp rockfish (Sebastes atrovirens), and 98 Pacific sanddab (Citharichthys sordidus) were collected from five offshore oil platforms and 10 natural areas during 2005-2006 for whole-body analysis of 63 elements. The natural areas, which served as reference sites, were assumed to be relatively uninfluenced by contaminants originating from platforms. Forty-two elements were excluded from statistical comparisons for one of three reasons: they consisted of major cations that were unlikely to accumulate to potentially toxic concentrations under ambient exposure conditions; they were not detected by the analytical procedures; or they were detected at concentrations too low to yield reliable quantitative measurements. The remaining 21 elements consisted of aluminum, arsenic, barium, cadmium, chromium, cobalt, copper, gallium, iron, lead, lithium, manganese, mercury, nickel, rubidium, selenium, strontium, tin, titanium, vanadium, and zinc. Statistical comparisons of these 21 elements indicated that none consistently exhibited higher concentrations at oil platforms than at natural areas. Eight comparisons yielded significant interaction effects between total length (TL) of the fish and the two habitat types (oil platforms and natural areas). This indicated that relations between certain elemental concentrations (i.e., copper, rubidium, selenium, tin, titanium, and vanadium) and habitat type varied by TL of affected fish species. To better understand these interactions, we examined elemental concentrations in very small and very large individuals of affected species. Although significant interactions were detected for rubidium, tin, and selenium in kelp rockfish, the concentrations of these elements did not differ significantly between

  1. Cape Lookout Bight sea turtle survey

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Seasonal capture efforts were conducted to evaluate patterns of catch rates, species and size compisition. Acoustic and satellite telemetry were used to evaluate...

  2. New York Bight Study: Report 5, NY Bight Biological Review Program

    Science.gov (United States)

    1994-05-01

    final cap has been recolonized due to changes in granulome - tVy and stress from chronic burial. The procedure and information available for examining this...34 Linear oceanographic features: A focus for research on recruitment processes," Australian Journal of Ecology 15, 391-401. Kiorboe, T., Munk, P., Richardson

  3. The legacy of sewage sludge disposal in New York bight

    Energy Technology Data Exchange (ETDEWEB)

    Buchholtz ten Brink, M.; Casso, M.A. [Geological Survey, Woods Hole, MA (United States); Allison, M.A. [Texas A and M Univ., Galveston, TX (United States); Schleel, J.S.

    1995-12-31

    From 1924 until 1987, New York City disposed of sewage sludge by dumping at the 12-mile dumpsite in 20 m of water off the New York-New Jersey coast. Approximately 125 {times} 10{sup 6} m{sup 3} was deposited, peaking in the early 1980`s. The dumpsite is at the head of the Hudson Shelf Valley, a submerged river channel crossing the continental shelf, in a region of sandy sediments that are regularly reworked by wave action. The introduction of the chemically and texturally distinct `sludge` sediment provides a tracer to study how accumulated anthropogenic deposits are dispersed throughout the region or transferred off the shelf. This work, begun in 1992, focuses on the fate of the material in the valley, ``downstream`` from the dumpsite. Geophysical, chemical, and radiological tools were used to delineate the sedimentary processes, the extent of contaminant dispersal, and the longterm fate of the dump spoils. Sediment derived from the sewage sludge has preferentially deposited on the valley floor relative to the surrounding shelf, resulting in unnaturally high accumulation rates in the upper valley. Dark, sludge-derived sediment is being covered by cleaner deposits from 0 to 26 km downvalley from the dumpsite, but ongoing resuspension and transport of the sediment results in a sewage signal in the uppermost sediments up to 80 km from the dumpsite. Both buried and surface ``sludge`` is subject to biological mixing. The patchy occurrence of the black sediment and interbedded sand layers observed downvalley suggest that resuspension and transport occur episodically, probably during major storm events.

  4. New York Bight sub-estuaries Study following Hurricane Sandy

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Polychlorinated biphenyls (PCBs), organochlorine pesticides, polybrominated diphenyl ethers (PBDEs), polycyclic aromatic hydrocarbons (PAHs) and alkylated PAHs,...

  5. Trace element geochemistry of the South Atlantic Bight: Progress report

    International Nuclear Information System (INIS)

    Windom, H.L.

    1987-12-01

    Our major field effort involved participation in FLEX. Approximately 350 samples were collected for trace metal analyses. All of the SPREX data has been reduced and interpreted. One proposed paper describes a model for the flux of particulate material across the continental shelf. This model was applied to the particulate aluminum data collected during SPREX and will be used to estimate cross-shelf fluxes of particulate trace metals. The model will also serve as a basis for developing further models for freshwater, PON and POC fluxes during SPREX and FLEX. Another manuscript describes the estuarine behavior of plutonium and lead 210. A third manuscript describes trace metal behavior in the Savannah River estuary. All analyses and data reduction for Phase 1 and 2 sediment sampling campaigns have been completed. One paper, submitted for publication, shows that the major metal bearing phase in these sediments is aluminosilicate minerals. We will be interpreting these results during the coming year to estimate nearshore sediment removal of trace metals and nutrients and their cycling. Analyses of all pre-FLEX suspended sediment samples have been completed and will be used, with SPREX and FLEX data, to elucidate temporal variability on the composition of nearshore particles. Phase 3 sediments that were collected during our pre-FLEX Blue Fin cruise have been partially completed. 1 fig

  6. Trace element geochemistry of the South Atlantic Bight. Progress report

    International Nuclear Information System (INIS)

    Windom, H.L.; Wallace, G.T.

    1980-03-01

    This report summarizes research conducted during the past year under DOE Contract EY-76-S-09-0890. During this time, studies have been continued in the mid to outer continental shelf region. We have also initiated nearshore studies designed to elucidate processes influencing the fate of trace elements in estuaries and the coastal frontal zone. A smaller effort has been concerned with preliminary geochemical studies of uranium-thorium natural decay series radionuclides and with improvement, calibration, and expansion of our trace element laboratory procedures

  7. Trace element geochemistry of the South Atlantic Bight. Progress report, June 1, 1976--May 31, 1977

    International Nuclear Information System (INIS)

    Windom, H.L.

    1977-01-01

    Ten major rivers of the southeastern United States have been sampled monthly over a year period for copper and for six months for nickel and zinc. One year's data has also been obtained for mercury and arsenic. The locations of the Atlantic Ocean continental shelf surface water samples collected during the past year are shown. During the same cruises atmospheric samples were also collected. The data indicate that: the most important input mechanism for trace elements to the continental shelf is intrusions with the possible exception of mercury which has an equally important input via the atmosphere; the residence times of all the trace elements studied in continental shelf waters are similar (about 0.26 yr) but different from that of water (0.37 yr); a portion of trace elements transported to the shelf by rivers may be lost by incorporation onto particles that are swept off the shelf or deposited on the bottom; and trace elements are apparently regenerated at depth in the Gulf Stream and off shelter waters, and increased levels may be correlated with nutrient concentrations. A list is included of published papers that report the results in detail

  8. Estimation of The Physico-Chemical Parameters in Marine Environment (Yumurtalik Bight- Iskenderun Bay

    Directory of Open Access Journals (Sweden)

    Gökhan Tamer Kayaalp

    2016-02-01

    Full Text Available The study was carried out to estimate the temperature, light intensity, salinity, Dissolved O2 (DO, pH values and the biotic parameter chlorophyll- a in the water column related with the depth. Because, the physico-chemical parameters affect greatly both primary and secondary producers in marine life. For this purpose the physico-chemical properties were determined day and night for 40 meter depth during the eight days. The means were compared by using the analysis of variance method and Duncan’s Multiple Comparison Test. Also physico-chemical parameters were estimated by using the analysis of regression and correlation. The effect of temperature and salinity were found significant according to the result of the analysis of variance during the day. Also the similar results were found for the night. While the effect of the depth on the chloropyll-a a was significant in the night, the effect of the depth on the DO was not significant in the day and night. The correlations among the depth and the parameters were defined. It was found the negative correlation between the depth and the temperature and light intensity. Determination coefficient of the model for salinity was also found different for day time. The correlation values among the depth and the temperature, salinity and pH were found different for the night.

  9. Ecological and political issues surrounding decommissioning of offshore oil facilities in the Southern California Bight

    Science.gov (United States)

    Schroeder, Donna M.; Love, Milton S.

    2004-01-01

    To aid legislators, resource managers, and the general public, this paper summarizes and clarifies some of the issues and options that the federal government and the state of California face in decommissioning offshore oil and gas production platforms, particularly as these relate to platform ecology. Both local marine ecology and political climate play a role in decommissioning offshore oil production platforms. Compared to the relatively supportive political climate in the Gulf of Mexico for “rigs-to-reefs” programs, conflicting social values among stakeholders in Southern California increases the need for understanding ecological impacts of various decommissioning alternatives (which range from total removal to allowing some or all of platform structure to remain in the ocean). Additional scientific needs in the decommissioning process include further assessment of platform habitat quality, estimation of regional impacts of decommissioning alternatives to marine populations, and determination of biological effects of any residual contaminants. The principal management need is a ranking of environmental priorities (e.g. species-of-interest and marine habitats). Because considerable numbers of economically important species reside near oil platforms, National Oceanic and Atmospheric Administration Fisheries should consider the consequences of decommissioning alternatives in their overall management plans. Management strategies could include designating reefed platforms as marine protected areas. The overarching conclusion from both ecological and political perspectives is that decommissioning decisions should be made on a case-by-case basis.

  10. Modeling of Habitat and Foraging Behavior of Beaked Whales in the Southern California Bight

    Science.gov (United States)

    2015-09-30

    a species label. Data from acoustic line-transect surveys (2008-2011) carried out by NOAA Southwest Fisheries Science Center (Jay Barlow ) in...published, refereed] Baumann-Pickering S, Yack TM, Barlow J, Wiggins SM, Hildebrand JA (2013) Baird’s beaked whale echolocation signals. J Acoust Soc Am 133...4321-4331 [published, refereed] Yack TM, Barlow J, Calambokidis J, Southall B, and Coates S (2013) Identification of previously unknown beaked

  11. Phytoplankton biomass and primary production in Delagoa Bight Mozambique: Application of remote sensing

    Digital Repository Service at National Institute of Oceanography (India)

    Kyewalyanga, M.S.; Naik, R.; Hegde, S.; Raman, M.; Barlow, R.; Roberts, M.

    @rediffmail.com (R. Naik), hegdesahana@rediffmail. com (S. Hegde), mraman@sac.isro.gov.in (M. Raman), rgbarlow@deat.gov. za (R. Barlow), squid@metroweb.co.za (M. Roberts). 0272-7714/$ - see front matter C211 2007 Elsevier Ltd. All rights reserved. doi:10.1016/j...

  12. History of metal pollution in the Southern California Bight: an update

    International Nuclear Information System (INIS)

    Finney, B.P.; Huh, C.

    1989-01-01

    Box cores collected in 1985 and 1986 along an offshore transect in the Santa Monica Basin, CA, were analyzed for organic carbon, calcium carbonate, U-series radionuclides, and a suite of major and minor elements. Downcore profiles of metals and organic carbon reflect anthropogenic influence and diagenetic processes. The deep basin cores show pronounced subsurface maxima in Pb, Zn, Cr, and organic carbon during the time interval 1960-1970. Increases from the base of the core to this time horizon are consistent with increasing anthropogenic inputs to the Santa Monica Basin. The near-surface decreases in heavy-metal accumulation reflect recent improvements in waste water treatment. Sediment compositions cannot be fully explained by simple mixtures of sewage particles and natural sediment because of factors such as diagenesis of sewage during transport and sedimentation, additional metal sources, and variations in surface water productivity. The yellow-brown surface layer in deep basin cores is relatively enriched in Fe, Co, Cu, and P. This layer forms by reduction of Fe followed by upward diffusion and precipitation as amorphous oxyhydroxides; P, Cu, and Co, released during early diagenesis, are associated with this phase

  13. Delft3D-Modelling of Hydrodynamic and Water Quality Processes in San Diego Bight

    Science.gov (United States)

    2010-09-30

    Terrill (SIO Scripps), Dr. Lyle Hibler ( PNL ) and Mark Moline (CalPoly) who are funded separately. LONG-TERM GOALS The long-term goal of this effort is...October 3, 2002. RELATED PROJECTS This work is a cooperation with Dr. Eric Terrill (SIO Scripps), Dr. Lyle Hibler ( PNL ) and Mark Moline (CalPoly) who are funded separately. 5

  14. EPXMA survey of shelf sediments (Southern Bight, North Sea): A glance beyond the XRD-invisible

    NARCIS (Netherlands)

    De Maeyer-Worobiec, A.; Dekov, V.M.; Laane, R.W.P.M.; van Grieken, R.

    2009-01-01

    Shelf sediments of the southern North Sea, were studied with a microanalytical [electron probe X-ray microanalysis (EPXMA)] and two bulk [X-ray diffraction (XRD) and X-ray fluorescence (XRF)] techniques. The investigation proved that the promptness of the microanalytical method is combined with a

  15. Sediment waves with a biogenic twist in Pleistocene cool water carbonates, Great Australian Bight

    DEFF Research Database (Denmark)

    Anderskouv, Kresten; Surlyk, Finn; Huuse, Mads

    2010-01-01

    -parallel to contours immediately off the shelf–slope break. They are asymmetrical, showing up-slope migration, and mainly occur in trains. The sediment waves were drilled during ODP leg 182 in 1998, and were interpreted as biogenic reef mounds. New high-quality seismic and multibeam bathymetry data were acquired...... involved growth in glacial periods only. Bryozoans influenced the depositional environment by adding sediment, trapping fine-grained particles, and stabilizing the muddy sea floor. This caused the sediment waves to gain a more prominent sea floor relief than most muddy siliciclastic sediment waves formed...

  16. Environmental factors affecting methane distribution and bacterial methane oxidation in the German Bight (North Sea)

    Czech Academy of Sciences Publication Activity Database

    Osudar, R.; Matoušů, Anna; Alawi, M.; Wagner, D.; Bussmann, I.

    2015-01-01

    Roč. 160, July (2015), s. 10-21 ISSN 0272-7714 R&D Projects: GA ČR(CZ) GA13-00243S Institutional support: RVO:60077344 Keywords : methanotrophy * estuary * Elbe River Subject RIV: DA - Hydrology ; Limnology Impact factor: 2.335, year: 2015

  17. CHROMOPHORIC DISSOLVED ORGANIC MATTER (CDOM) SOURCE CHARACTERIZATION IN THE LOUISIANA BIGHT

    Science.gov (United States)

    Chromophoric dissolved organic matter (CDOM) in the Mississippi plume region may have several distinct sources: riverine (terrestrial soils), wetland (terrestrial plants), biological production (phytoplankton, zooplankton, microbial), and sediments. Complex mixing, photodegradati...

  18. Statistics of AUV's Missions for Operational Ocean Observation at the South Brazilian Bight.

    Science.gov (United States)

    dos Santos, F. A.; São Tiago, P. M.; Oliveira, A. L. S. C.; Barmak, R. B.; Miranda, T. C.; Guerra, L. A. A.

    2016-02-01

    The high costs and logistics limitations of ship-based data collection represent an obstacle for a persistent in-situ data collection. Satellite-operated Autonomous Underwater Vehicles (AUV's) or gliders (as these AUV's are generally known by the scientific community) are presented as an inexpensive and reliable alternative to perform long-term and real-time ocean monitoring of important parameters such as temperature, salinity, water-quality and acoustics. This work is focused on the performance statistics and the reliability for continuous operation of a fleet of seven gliders navigating in Santos Basin - Brazil, since March 2013. The gliders performance were evaluated by the number of standby days versus the number of operating days, the number of interrupted missions due to (1) equipment failure, (2) weather, (3) accident versus the number of successful missions and the amount and quality of data collected. From the start of the operations in March 2013 to the preparation of this work (July 2015), a total of 16 glider missions were accomplished, operating during 728 of the 729 days passed since then. From this total, 11 missions were successful, 3 missions were interrupted due to equipment failure and 2 gliders were lost. Most of the identified issues were observed in the communication with the glider (when recovery was necessary) or the optode sensors (when remote settings solved the problem). The average duration of a successful mission was 103 days while interrupted ones ended on average in 7 days. The longest mission lasted for 139 days, performing 859 continuous profiles and covering a distance of 2734 Km. The 2 projects performed together 6856 dives, providing an average of 9,5 profiles per day or one profile every 2,5 hours each day during 2 consecutive years.

  19. Interannual variability of sorted bedforms in the coastal German Bight (SE North Sea)

    Science.gov (United States)

    Mielck, F.; Holler, P.; Bürk, D.; Hass, H. C.

    2015-12-01

    Sorted bedforms are ubiquitous on the inner continental shelves worldwide. They are described as spatially-grain-size-sorted features consisting of small rippled medium-to-coarse sand and can remain stable for decades. However, the knowledge about their genesis and development is still fragmentary. For this study, a representative investigation area (water depthwinnowing and focusing processes take place during periodically recurring storm surges, which change the shapes of the features. Moreover, variations in alignments and sizes of the small ripple formations were detected. They seem to indicate the directions and intensities of previous storm events.

  20. Characterisation of hard-substrate habitats in the German Bight (SE North Sea) from video observation

    Science.gov (United States)

    Michaelis, Rune; Mielck, Finn; Papenmeier, Svenja; Sander, Lasse; Hass, H. Christian

    2017-04-01

    Accumulations of cobble- to boulder-sized material provide important habitat functions for many plant and animal species in the marine environment. These include nursery for fish, anchor point for sessile marine species and feeding ground for many different organisms. Detailed knowledge of such reef habitats and their properties is thus crucial for the determination of marine protected areas and consequently also for the management of the North Sea. As stones and boulders usually cannot be recovered from the seafloor to be investigated in the lab most analyses have to rely on non-invasive methods like e.g. underwater video- and diver-observation data. Due to these limitations these habitats are not well understood with regard to their spatial distribution, temporal development and ecology. Furthermore, there is no standardized way to assess the structure and cover of biological communities on such hard-substrates, which discourages comparison of data between different regions. We here present a standardized workflow to analyse underwater videos of hard-substrate habitats recorded in different areas of the North Sea. The idea is to combine these detailed information with an area-wide habitat classification based on sidescan sonar data. For image-based evaluation, the videos are transformed into single frames, extracted every five seconds of video running time and imported into a self-developed image analysis script. This script allows the user to select and count different descriptors in numerical categories. These include amongst others the different size classes of stones, the areal coverage of sessile marine organisms, the surrounding sediment properties or the presence of grazers. These semi-quantitative data are subsequently statistically analysed to produce a set of standardized characteristics of the hard-substrate habitats and the controlling factors of their current state and development. Preliminary results show that boulders in sandy environments are predominantly covered by sessile invertebrate organisms (e.g. the soft coral Alcyonium digitatum and the sea-anemone Metridium senile), while cobbles are largely uncovered. In muddy areas, however, even cobbles show a higher amount of sessile coverage though at an earlier or reduced state of development. The proposed method allows to obtain detailed data on the distribution, kind and composition of marine sessile organisms populating hard-substrate habitats in the North Sea. Already at this stage, the practical assumption of many investigations that stones are all and always inhabited by the typical organisms, which is utilized in many investigations can hardly be supported. Our research further shows the need to develop methodologies to upscale these observations to be able to assess spatial patterns between and within larger reef complexes. The video analysis presents a valuable first step towards a full-scale characterization of hard-substrate habitats under difficult survey conditions.

  1. Southern California Hook and Line Survey - Annual So. CA Bight hook and line data collection/survey

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is an annual, fishery-independent survey aimed at collecting abundance and biological data for use in the stock assessments of several key rockfish species...

  2. Impact of Hurricane Irma in the post-recovery of Matthew in South Carolina, the South Atlantic Bight (Western Atlantic)

    Science.gov (United States)

    Harris, M. S.; Levine, N. S.; Jaume, S. C.; Hendricks, J. K.; Rubin, N. D.; Hernandez, J. L.

    2017-12-01

    The impacts on the Southeastern United States (SEUS, Western Atlantic) from Hurricane Irma in Sept 2017 were felt primarily on the active coastline with the third highest inland storm surge in Charleston and Savannah since the 19th Century. Coastal geometry, waves, and wind duration had a strong influence on the storm surge and coastal erosion impacts regionally. To the North and immediate South, impacts were much less. A full year after the 2016 hurricane season (Hurricane Matthew), the lack of regional recovery reduced protection against Irma. The most devastating impacts of Irma in the SAB occurred from 300 to 500 km away from the eye, on the opposite side of the Floridian peninsula. As Irma devastated the Caribbean, winds started to increases off the SAB on September 8 in the early morning, continuing for the next 3 days and blowing directly towards the SC and GA coasts. Tide gauges started to respond the night of September 8, while waves started arriving in the SEUS around Sept 6. Coastal erosion pre- and post-Irma has been calculated for Central SC using vertical and oblique aerial photos. Citizen Science initiatives through the Charleston Resilience Network have provided on-the-ground data during storms when transportation infrastructures were closed, and allow for ground-truth post-storm of surge and impacts. Said information was collected through Facebook, Google, and other social media. Pictures with timestamps and water heights were collected and are validating inundation flood maps generated for the Charleston SC region. The maps have 1-m horizontal and 7- to 15-cm vertical accuracy. Inundation surfaces were generated at MHHW up to a maximum surge in 6 inch increments. The flood extents of the modeled surge and the photographic evidence show a high correspondence. Storm surge measurements from RTK-GPS provide regional coverage of surge elevations from the coast, inland, and allow for testing of modeled results and model tuning. With Hurricane Irma hitting the SEUS at barely tropical storm power, the level of impact only amplifies the need for more extensive understanding of increased sea-level rise, of poorly understood coastal dynamics in the region, and of infrastructure exposed to more extreme conditions, as our beaches continue to collapse in the face of poor coastal management paradigms.

  3. Autotrophic and heterotrophic activity in Arctic first-year sea-ice: Seasonal study from Marlene Bight, SW Greenland

    DEFF Research Database (Denmark)

    Søgaard, Dorte Haubjerg; Kristensen, Morten; Rysgaard, Søren

    2010-01-01

    in situ in plastic bags with subsequent melting and measurements of changes in total O-2 concentrations. The standard incubations showed that the annual succession followed a distinctive pattern, with a low, almost balancing heterotrophic and autotrophic activity during February and March. This period...

  4. Multiple Stressors at the Land-Sea Interface: Cyanotoxins at the Land-Sea Interface in the Southern California Bight.

    Science.gov (United States)

    Tatters, Avery O; Howard, Meredith D A; Nagoda, Carey; Busse, Lilian; Gellene, Alyssa G; Caron, David A

    2017-03-09

    Blooms of toxic cyanobacteria in freshwater ecosystems have received considerable attention in recent years, but their occurrence and potential importance at the land-sea interface has not been widely recognized. Here we present the results of a survey of discrete samples conducted in more than fifty brackish water sites along the coastline of southern California. Our objectives were to characterize cyanobacterial community composition and determine if specific groups of cyanotoxins (anatoxins, cylindrospermopsins, microcystins, nodularins, and saxitoxins) were present. We report the identification of numerous potentially harmful taxa and the co-occurrence of multiple toxins, previously undocumented, at several locations. Our findings reveal a potential health concern based on the range of organisms present and the widespread prevalence of recognized toxic compounds. Our results raise concerns for recreation, harvesting of finfish and shellfish, and wildlife and desalination operations, highlighting the need for assessments and implementation of monitoring programs. Such programs appear to be particularly necessary in regions susceptible to urban influence.

  5. The mud deposits and the high turbidity in the Belgian-Dutch coastal zone, Southern Bight of the North Sea

    OpenAIRE

    Fettweis, M.; Van den Eynde, D.

    2003-01-01

    The suspended sediment processes and the mudfields found in the Belgian/Dutch coastal area (Southern North Sea) are discussed by presenting an integrated data-modelling approach of the suspended sediment transport along the Belgian-Dutch coast, using a fine-grid coupled 2D hydrodynamic and sediment transport model and existing field and literature data. These mudfields and turbidity maxima are situated in a well-mixed, highly energetic hydrodynamic environment. In the past the occurrence of t...

  6. Distributions and habitat associations of deep-water corals in Norfolk and Baltimore Canyons, Mid-Atlantic Bight, USA

    NARCIS (Netherlands)

    Brooke, S.D.; Watts, M.W.; Heil, A.D.; Rhode, M.; Mienis, F.; Duineveld, G.C.A.; Davies, A.J.; Ross, S.W.

    2017-01-01

    A multi-disciplinary study of two major submarine canyons, Baltimore Canyon and Norfolk Canyon, off the US mid-Atlantic coast focused on the ecology and biology of canyon habitats, particularly those supporting deep-sea corals. Historical data on deep-sea corals from these canyons were sparse with

  7. Small scale patches of suspended matter and phytoplankton in the Elbe river estuary, German Bight and tidal flats

    Energy Technology Data Exchange (ETDEWEB)

    Doerffer, R; Fischer, J; Stoessel, M; Brockmann, C [GKSS-Forschungszentrum Geesthacht GmbH, Geesthacht-Tesperhude (Germany, F.R.); Grassl, H [Max-Planck-Institut fuer Meteorologie, Hamburg (Germany, F.R.)

    1989-01-01

    Thematic mapper and ship data has been used to study small scale features in coastal waters of the North Sea. Three independent pieces of informations from all 7 TM channels were found with factor analysis: suspended matter concentration, atmospheric scattering and sea surface temperature. Near surface suspended matter concentrations may be detected within a factor of 2. For the required atmospheric correction the signal-to-noise ratio of the channels 5 and 7 has to be improved by averaging over 25 x 25 pixels. Thus TM allows to monitor aerosol optical depth and aerosol type over cloudfree water surfaces. Sea surface temperature is retrievable with an absolute accuracy of 1.0 K as long as radiosonde data are available for the correction of atmospheric effects, while relative temperature variations of 0.5 K are detectable. The patchiness of suspended matter and its relation to underwater topography was analysed with auto- and crosscorrelation: horizontal lengths, where the suspended matter concentration of single pixels are significantly correlated either with each another or with water depth, are < 800 m. (orig.).

  8. NOAA TIFF Image - 4m Bathymetric Depth of Red Snapper Research Areas in the South Atlantic Bight, 2010

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains unified Bathymetric Depth GeoTiffs with 4x4 meter cell resolution describing the topography of 15 areas along the shelf edge off the South...

  9. NOAA TIFF Image - 4m Bathymetric Curvature of Red Snapper Research Areas in the South Atlantic Bight, 2010

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains unified Bathymetric Curvature GeoTiffs with 4x4 meter cell resolution describing the topography of 15 areas along the shelf edge off the South...

  10. NOAA TIFF Image - 4m Bathymetric Mean Depth of Red Snapper Research Areas in the South Atlantic Bight, 2010

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains unified Bathymetric Mean Depth GeoTiffs with 4x4 meter cell resolution describing the topography of 15 areas along the shelf edge off the South...

  11. NOAA TIFF Image - 4m Bathymetric Depth Range of Red Snapper Research Areas in the South Atlantic Bight, 2010

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains unified Bathymetric Depth Range GeoTiffs with 4x4 meter cell resolution describing the topography of 15 areas along the shelf edge off the...

  12. NOAA TIFF Image - 4m Multibeam Backscatter for Red Snapper Research Areas in the South Atlantic Bight, 2010

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains unified Multibeam Backscatter GeoTiffs with 4x4 meter cell resolution describing the geomorphology of 15 areas along the shelf edge off the...

  13. Comparison of the diel and spatial distribution patterns of ichthyoplankton and ichthyoneuston in the Southeastern Brazilian Bight

    Directory of Open Access Journals (Sweden)

    Mario Katsuragawa

    1990-12-01

    Full Text Available Fish larvae were collected by neuston and bongo nets, in the Southeastern Brazil, during four océanographie cruises (January 1980; January 1981; October 1981; and March 1982. The results are compared and analyzed in order to study the patterns of diel vertical distributions of fish larvae and to detect sampling problems. Larvae collected with neuston net were quite different in types and size composition, when compared with those collected with bongo net in oblique tows. Clear tendency of stratification in size composition at the uppermost layer can be observed on juveniles ( > 19 mm of Sardinella brasiliensis which also showed day time avoidance. Most of the neustonic taxa were also caught in the deeper layers, although some groups, e.g. Mugilidae, Mullidae, and Gerreidae, were more abundant at the surface. Density of ichthyoneuston is much higher than those observed in the Northwest Atlantic and number of fish larvae collected during the day by neuston net exceeded that of night samples.Larvas de peixes foram coletadas com rede de nêuston e rede bongô, na costa sudeste do Brasil, durante quatro cruzeiros oceanográficos (Jan/1980; Jan/1981; Out/1981; Mar/1982. São estudados os padrões de distribuição diária de larvas e problemas de amostragem. Numa comparação entre coletas de superfície e coletas oblíquas, observam-se diferenças em composição, tanto em termos de espécies como de tamanho de larvas. Pode ser observada uma clara tendência de estratificação por composição de tamanho para Sardinella brasiliensis em que espécimes juvenis (> 19 mm ocorreram preferencialmente na camada superficial. Estes juvenis também apresentaram maior capacidade de fuga da boca da rede durante o período diurno. A maioria dos táxons de ocorrência neustônica foi também capturada em camadas mais profundas, mas alguns grupos como Mugilidae, Mullidae e Gerreidae predomiram na camada superficial. A densidade do ictionêuston é mais elevada na nossa região do que a observada no Atlântico noroeste, e o numero de larvas de peixes da coleta diuna com rede de nêuston excedeu o da coleta noturna.

  14. Spatio-Temporal Distribution of Particulate and CDOM in the Mississippi River Bight (MRB) from Optical Measurements

    Science.gov (United States)

    D'Sa, Eurico; Miller, Richard; DelCastillo, Carlos

    2004-01-01

    NASA's projects for the Mississippi River Coastal Margin Study include Mississippi River Interdisciplinary Research (MiRIR) and NASA Experimental Program to Stimulate Competitive Research (EPSCoR). These projects, undertaken with the help of Tulane University and the Louisiana Universities Marine Consortium (LUMCON) sampled water in the Gulf of Mexico to measure colored dissolved organic matter (CDOM). This viewgraph presentation contains images of each program's sampling strategy and equipment.

  15. South Atlantic Bight Habitat Mapping on NOAA Ship Nancy Foster in North Atlantic Ocean between 20070626 and 20070702

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This expedition on the NOAA Ship Nancy Foster used the recently-developed National Undersea Research Center for the North Atlantic and Great Lakes (NURC-NAGL) ROV...

  16. Export of a Winter Shelf Phytoplankton Bloom at the Shelf Margin of Long Bay (South Atlantic Bight, USA)

    Science.gov (United States)

    Nelson, J.; Seim, H.; Edwards, C. R.; Lockhart, S.; Moore, T.; Robertson, C. Y.; Amft, J.

    2016-02-01

    A winter 2012 field study off Long Bay (seaward of Myrtle Beach, South Carolina) investigated exchange processes along the shelf margin. Topics addressed included mechanisms of nutrient input (upper slope to outer shelf), phytoplankton blooms and community characteristics (mid-to-outer shelf), and possible export of shelf bloom material (transport to and across the shelf break to the upper slope). Observations utilized three moorings (mid-shelf, shelf break, upper slope), two gliders and ship operations (repeat cruises with profiling, water sampling and towed body surveys) along with satellite SST and ocean color imagery and near-by NOAA buoy records. Here we focus on the late January to early February period, when a mid-shelf bloom of Phaeocystis globosa (which forms large gelatinous colonies) was transported to the shelf break. The presence of Phaeocystis colonies resulted in strong spiking in chlorophyll (chl) fluorescence profiles. A partitioning approach was adapted to estimate chl in colonies (spikes) and small forms (baseline signal) and to account for an apparent difference in measured in vivo fluorescence per unit chl (lower in colonies). Up to 40-50% of chl in the bloom (surface to bottom on the mid-shelf) was estimated to be in the colonies. In late January, there a pronounced seaward slumping of relatively dense mid-shelf water along the bottom under warmer surface water derived from the inshore edge of a broad jet of Gulf Stream water flowing southwestward along the upper slope. We describe the evolution of this event and the conditions which set up this mechanism for episodic near-bed transport of fresh bloom material produced on the shelf to the upper slope off Long Bay. Down-slope transport may have been enhanced in this case by the high phytoplankton biomass in gelatinous colonies, which appeared to be settling in the water column on the shelf prior to the transport event.

  17. Tidal-controlled variations of primary- and secondary bedform height: Innenjade tidal channel (Jade Bay, German Bight)

    DEFF Research Database (Denmark)

    Ernstsen, Verner B.; Winter, C.; Becker, M.

    2010-01-01

    Coastal, estuarine, fluvial and submarine morphodynamics encompass some of the leading processes shaping our planet. They stem mainly, but not only, from the interaction of water in motion and movable sediment boundaries, resulting in morphological changes produced by erosion, transport and depos......Coastal, estuarine, fluvial and submarine morphodynamics encompass some of the leading processes shaping our planet. They stem mainly, but not only, from the interaction of water in motion and movable sediment boundaries, resulting in morphological changes produced by erosion, transport...... and deposition of sediments that generate a variety of landscapes and seascapes over time. Morphodynamics allows for a better understanding and interpretation of self adjustments in drainage basins, longitudinal river profiles and shorelines shapes, as well as characteristic features such as beach cusps, bed...... forms such as dunes, and channel patterns. This collection of about 150 contributions should be invaluable to wetland ecologists, fish biologists, engineers, geomorphologists, fluvial engineers, coastal scientists , as well as to scientists interested in processes responsible for earth-surface landscape...

  18. Environmental survey of two interim dumpsites, Middle Atlantic Bight from 05 November 1973 to 10 November 1973 (NODC Accession 7501280)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A second oceanographic survey cruise was made to an interim municipal sludge dumpsite and initially to an interim dumpsite for the disposal of industrial acid waste...

  19. Photosynthesis, respiration, and carbon turnover in sinking marine snow from surface waters of Southern California Bight: implications for the carbon cycle in the ocean

    DEFF Research Database (Denmark)

    Ploug, H.; Grossart, HP; Azam, F.

    1999-01-01

    aggregate in darkness, which yielded a turnover time of 8 to 9 d for the total organic carbon in aggregates. Thus, marine snow is not only a vehicle for vertical flux of organic matter; the aggregates are also hotspots of microbial respiration which cause a fast and efficient respiratory turnover...... of particulate organic carbon in the sea....

  20. NOAA TIFF Image - 3m Multibeam Bathymetry, Miami, South Atlantic Bight - Deep Coral Priority Areas - Lost Coast Explorer - (2010), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 3x3 meter cell size representing the bathymetry of the continental shelf off of Jacksonville, FL in the South Atlantic...

  1. NOAA TIFF Image - 10m Bathymetric Slope, South Atlantic Bight - Deep Coral Priority Areas - NOAA Ship Nancy Foster - (2009), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 10x10 meter cell size representing the slope (in degrees) of several deep coral priority areas off the South Atlantic...

  2. Ensemble perturbation smoother for optimizing tidal boundary conditions by assimilation of High-Frequency radar surface currents – application to the German Bight

    Directory of Open Access Journals (Sweden)

    A. Barth

    2010-02-01

    Full Text Available High-Frequency (HF radars measure the ocean surface currents at various spatial and temporal scales. These include tidal currents, wind-driven circulation, density-driven circulation and Stokes drift. Sequential assimilation methods updating the model state have been proven successful to correct the density-driven currents by assimilation of observations such as sea surface height, sea surface temperature and in-situ profiles. However, the situation is different for tides in coastal models since these are not generated within the domain, but are rather propagated inside the domain through the boundary conditions. For improving the modeled tidal variability it is therefore not sufficient to update the model state via data assimilation without updating the boundary conditions. The optimization of boundary conditions to match observations inside the domain is traditionally achieved through variational assimilation methods. In this work we present an ensemble smoother to improve the tidal boundary values so that the model represents more closely the observed currents. To create an ensemble of dynamically realistic boundary conditions, a cost function is formulated which is directly related to the probability of each boundary condition perturbation. This cost function ensures that the boundary condition perturbations are spatially smooth and that the structure of the perturbations satisfies approximately the harmonic linearized shallow water equations. Based on those perturbations an ensemble simulation is carried out using the full three-dimensional General Estuarine Ocean Model (GETM. Optimized boundary values are obtained by assimilating all observations using the covariances of the ensemble simulation.

  3. Benthic and biological data in the New York Bight from 2010-06-01 to 2012-05-31 (NCEI Accession 0128996)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data sets show the distribution of key species and habitats, such as seabirds, bathymetry, surficial sediments, deep sea corals, and oceanographic habitats....

  4. BACTERIA - BACTERIAL DENSITY and Other Data from FIXED STATIONS From New York Bight and Others from 19680610 to 19901206 (NODC Accession 9100200)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The accession contains New York City Department Harbor Survey Data from years 1968 to 1990. Station data was collected as part of the NYC Department of Environmental...

  5. NOAA TIFF Image - 4m Bathymetric Principal Component Analysis (PCA) of Red Snapper Research Areas in the South Atlantic Bight, 2010

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains unified Bathymetric PCA GeoTiffs with 4x4 meter cell resolution describing the topography of 15 areas along the shelf edge off the South...

  6. Projected 21st century coastal flooding in the Southern California Bight. Part 2: Tools for assessing climate change-driven coastal hazards and socio-economic impacts

    Science.gov (United States)

    Erikson, Li; Barnard, Patrick; O'Neill, Andrea; Wood, Nathan J.; Jones, Jeanne M.; Finzi Hart, Juliette; Vitousek, Sean; Limber, Patrick; Hayden, Maya; Fitzgibbon, Michael; Lovering, Jessica; Foxgrover, Amy C.

    2018-01-01

    This paper is the second of two that describes the Coastal Storm Modeling System (CoSMoS) approach for quantifying physical hazards and socio-economic hazard exposure in coastal zones affected by sea-level rise and changing coastal storms. The modelling approach, presented in Part 1, downscales atmospheric global-scale projections to local scale coastal flood impacts by deterministically computing the combined hazards of sea-level rise, waves, storm surges, astronomic tides, fluvial discharges, and changes in shoreline positions. The method is demonstrated through an application to Southern California, United States, where the shoreline is a mix of bluffs, beaches, highly managed coastal communities, and infrastructure of high economic value. Results show that inclusion of 100-year projected coastal storms will increase flooding by 9–350% (an additional average 53.0 ± 16.0 km2) in addition to a 25–500 cm sea-level rise. The greater flooding extents translate to a 55–110% increase in residential impact and a 40–90% increase in building replacement costs. To communicate hazards and ranges in socio-economic exposures to these hazards, a set of tools were collaboratively designed and tested with stakeholders and policy makers; these tools consist of two web-based mapping and analytic applications as well as virtual reality visualizations. To reach a larger audience and enhance usability of the data, outreach and engagement included workshop-style trainings for targeted end-users and innovative applications of the virtual reality visualizations.

  7. Disturbance of Essential Fish Habitat by Commercial Passive Fishing Gear in the Delaware, Maryland, and Virginia region of the Mid-Atlantic Bight

    Science.gov (United States)

    Schweitzer, C.

    2016-02-01

    Trap fishing is one of the oldest methods utilized to capture fish, and fish traps are currently one of the most dominant fishing gears utilized by commercial fishermen in the DelMarVa (Delaware, Maryland, Virginia) region. Impacts of traps on benthic habitat and emergent epifauna have become an increasing concern since the 1990's, but despite this, there is little published data regarding trap-habitat interactions. Any substrate necessary for fish spawning, breeding, feeding, or growth to maturity is deemed Essential Fish Habitat (EFH) and in order to increase capture success, traps are often deployed near or on EFH. We assessed the degree of trap impacts via video observations from commercial traps at four common fishing sites in the DelMarVa region, 27-36 km off the coast, at depths of 20-30 m. Two traps within a 20 trap rig were customized by attaching GoPro® cameras to give views in front of the trap, toward the trap front, and to the rear of the trap. Analysis of 123 trap deployments shows that traps often drag across the ocean floor and habitats during the retrieval process. Duration of the dragging phase is strongly correlated with trap position on the line (r2=0.6; p<0.001); traps farther down the line drag significantly longer than traps closer to the boat and first retrieved (1st vs last trap: p<0.01). Dragging significantly increases trap-habitat interactions. Traps with minimal drag have <1% chance of contacting EFH but dragging increases the proportion of traps interacting with EFH to 46%. Observed trap-habitat interactions include: damaging and breaking coral, and running over sea stars, anemones, and bryozoans. Essential fish habitats located off the DelMarVa coast are highly fragmented and sparse, and adverse impacts of passive fishing gear probably affect a large portion of the available habitat.

  8. NOAA TIFF Image - 30m Slope, South Atlantic Bight - Deep Coral Priority Areas - USNS Pathfinder - (2003), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the slope (in degrees) of the 2003 multibeam bathymetry of the Charleston Bump off of...

  9. NOAA TIFF Image - 10m Bathymetry Mosaic, South Atlantic Bight - Deep Coral Priority Areas - NOAA Ron Brown - (2010), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 10x10 meter cell size representing the bathymetry (depth) of several deep coral priority areas off the South Atlantic...

  10. NOAA TIFF Image - 10m Backscatter Mosaic, South Atlantic Bight - Deep Coral Priority Areas - NOAA Ship Nancy Foster - (2009), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 10x10 meter cell size representing the backscatter (intensity) of several deep coral priority areas off the South...

  11. NOAA TIFF Image - 10m Bathymetric Slope, South Atlantic Bight - Deep Coral Priority Areas - NOAA Ship Ron Brown - (2010), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 10x10 meter cell size representing the slope (in degrees) of several deep coral priority areas off the South Atlantic...

  12. NOAA TIFF Image - 30m Slope, South Atlantic Bight - Deep Coral Priority Areas - Thomas Jefferson - (2007), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the slope (in degrees) of the multibeam bathymetry of the Charleston Bump off of the...

  13. NOAA TIFF Image - 10m Backscatter Mosaic, South Atlantic Bight - Deep Coral Priority Areas - NOAA Ship Nancy Foster - (2010), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 10x10 meter cell size representing the backscatter (intensity) of several deep coral priority areas off the South...

  14. NOAA TIFF Image - 5m Backscatter Mosaic, South Atlantic Bight - Deep Coral Priority Areas - NOAA Ship Nancy Foster - (2007), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 5x5 meter cell size representing the backscatter (intensity) of several deep coral priority areas off the South Atlantic...

  15. Projected 21st century coastal flooding in the Southern California Bight. Part 1: Development of the third generation CoSMoS model

    Science.gov (United States)

    O'Neill, Andrea; Erikson, Li; Barnard, Patrick; Limber, Patrick; Vitousek, Sean; Warrick, Jonathan; Foxgrover, Amy C.; Lovering, Jessica

    2018-01-01

    Due to the effects of climate change over the course of the next century, the combination of rising sea levels, severe storms, and coastal change will threaten the sustainability of coastal communities, development, and ecosystems as we know them today. To clearly identify coastal vulnerabilities and develop appropriate adaptation strategies due to projected increased levels of coastal flooding and erosion, coastal managers need local-scale hazards projections using the best available climate and coastal science. In collaboration with leading scientists world-wide, the USGS designed the Coastal Storm Modeling System (CoSMoS) to assess the coastal impacts of climate change for the California coast, including the combination of sea-level rise, storms, and coastal change. In this project, we directly address the needs of coastal resource managers in Southern California by integrating a vast range of global climate change projections in a thorough and comprehensive numerical modeling framework. In Part 1 of a two-part submission on CoSMoS, methods and the latest improvements are discussed, and an example of hazard projections is presented.

  16. Dredging Operations Technical Support Program. Evaluation of the 1980 Capping Operations at the Experimental Mud Dump Site, New York Bight Apex.

    Science.gov (United States)

    1983-10-01

    Christiaensen Basin e. NW Quad.-Dredge I4at’l Dump Site ( DMD ) f. 1 naut. mi. due W of DM0 Site - o . Stock Population from Cape Kay x. Capping Site (DM0...was 0.5 ppm. Cadmium contamination of the marine environment can be traced to a K wide range of industrial sources, including photography, lithography ...DDT,.in (birds interferes with calcium metabolism and results in thin egg shells, thereby increasing mortality among unhatched birds. Butler (1972

  17. On the dynamics of compound bedforms in high-energy tidal channels: field observations in the German Bight and the Danish Wadden Sea

    DEFF Research Database (Denmark)

    Ernstsen, Verner Brandbyge; Winter, Christian; Becker, Marius

    2010-01-01

    erosion in the trough is due to a combination of low flow velocity and the development of an armour layer of shell lag-deposits. Regarding secondary-bedform height, both tidal channels displayed a general increase with increasing mean flow velocity and a general decrease with decreasing mean flow velocity...

  18. Photosynthesis, respiration, and carbon turnover in sinking marine snow from surface waters of Southern California Bight: implications for the carbon cycle in the ocean

    DEFF Research Database (Denmark)

    Ploug, Helle; Grossart, Hans-Peter; Azam, F.

    1999-01-01

    Photosynthesis and respiration were measured in 1 to 6 mm large aggregates (marine snow) collected in the Southern Californian Eight, USA. The aggregates were freely sinking in a vertical flow system with an upward flow velocity which opposed the sinking velocity of individual aggregates during...... techniques. Both the respiration rate per aggregate volume and the bacterial densities decreased with increasing aggregate size. The respiration rates normalized to the number of bacteria in single aggregates were 7.4 to 70 fmol C cell(-1) d(-1). The aggregate community respired 433 to 984 ng C d(-1) per...... aggregate in darkness, which yielded a turnover time of 8 to 9 d for the total organic carbon in aggregates. Thus, marine snow is not only a vehicle for vertical flux of organic matter; the aggregates are also hotspots of microbial respiration which cause a fast and efficient respiratory turnover...

  19. Thematic mapper research in the earth sciences: Small scale patches of suspended matter and phytoplankton in the Elbe River Estuary, German Bight and Tidal Flats

    Science.gov (United States)

    Grassl, H.; Doerffer, R.; Fischer, J.; Brockmann, C.; Stoessel, M.

    1987-01-01

    A Thematic Mapper (TM) field experiment was followed by a data analysis to determine TM capabilities for analysis of suspended matter and phytoplankton. Factor analysis showed that suspended matter concentration, atmospheric scattering, and sea surface temperature can be retrieved as independent factors which determine the variation in the TM data over water areas. Spectral channels in the near infrared open the possibility of determining the Angstrom exponent better than for the coastal zone color scanner. The suspended matter distribution may then be calculated by the absolute radiance of channel 2 or 3 or the ratio of both. There is no indication of whether separation of chlorophyll is possible. The distribution of suspended matter and sea surface temperature can be observed with the expected fine structure. A good correlation between water depth and suspended matter distribution as found from ship data can now be analyzed for an entire area by the synoptic view of the TM scenes.

  20. The Partitioning of Carbon Biomass among the Pico- and Nano-plankton Community in the South Brazilian Bight during a Strong Summer Intrusion of South Atlantic Central Water

    Directory of Open Access Journals (Sweden)

    Natascha M. Bergo

    2017-07-01

    Full Text Available To investigate how pico- and nano-plankton respond to oceanographic conditions in the Southwestern Atlantic Ocean, we assessed the influence of a summer intrusion of the South Atlantic Central Water (SACW on the spatial and vertical dynamics of planktonic abundance and carbon biomass across environmental gradients. Seawater samples were collected from six depths within the euphotic zone at nine oceanographic stations in a transect on the Brazilian continental shelf in January 2013. The abundance of pico- and nano-plankton populations was determined by flow cytometry, and carbon biomass was calculated based on conversion factors from the literature. The autotrophic Synechococcus spp., picoeukaryotes, and nanoeukaryotes were more abundant in the surface layers of the innermost stations influenced by Coastal Water (maximum of 1.19 × 105, 1.5 × 104, and 8.61 × 103 cell·mL−1, respectively, whereas Prochlorococcus spp. dominated (max. of 6.57 × 104 cell·mL−1 at the outermost stations influenced by Tropical Water and in the uplifting layers of the SACW around a depth of 100 m. Numerically, heterotrophic bacterial populations were predominant, with maximum concentrations (2.11 × 106 cell·mL−1 recorded in the surface layers of the inner and mid shelves in Coastal Water and the upper limits of the SACW. Nutrient-rich (high silicate and phosphate and relatively less saline waters enhanced the picoeukaryotic biomass, while Synechococcus and heterotrophic bacteria were linked to higher temperatures, lower salinities, and higher inputs of ammonia and dissolved organic carbon. The relative importance of each group to carbon biomass partitioning under upwelling conditions is led by heterotrophic bacteria, followed by picoeukaryotes, Synechococcus and Prochlorococcus, and when the SACW is not as influential, the relative contribution of each phytoplanktonic group is more evenly distributed. In addition to habitat preferences, the physical structure of oligotrophic waters has a large impact on the vertical and spatial distribution patterns of picoplankton, reflecting the strong effect of the SACW intrusion.

  1. Geologic Seafloor Mapping Defines Extensive Paleochannel Network Offshore of the Delmarva Peninsula, U.S.A: Implications for Mid-Atlantic Bight Evolution since the Pliocene

    Science.gov (United States)

    Brothers, L. L.; Foster, D. S.; Pendleton, E. A.; Thieler, E. R.; Baldwin, W. E.; Sweeney, E. M.

    2017-12-01

    Nearly 10,000 km of geophysical data and seafloor grab samples along with photo and video data from more than 200 seafloor stations are used to interpret seafloor and shallow subsurface geology on the Delmarva Peninsula's inner continental shelf. These USGS data are supplemented with existing National Oceanic Atmospheric Administration hydrographic survey data and Bureau of Ocean Energy Management Wind Energy Area seismic reflection profile data to support one of the most data-rich and extensive inner continental shelf studies on the U.S. Atlantic coast. Using chirp, multi-channel boomer and sparker seismic reflection profile data, we map an extensive paleochannel network from 500 meters to 30 kilometers offshore of the modern Delmarva coastline. Fluvial erosional surfaces relating to six sea-level lowstands are identified at two-way travel times between 0.01 and 0.12 ms. Paleochannels exhibit up to 30 meters of relief and the discrete complexes can be >25 kilometers wide. Based on areal distribution, stratigraphic relationships and amino acid dating results from earlier borehole studies, we interpret the infilled channels as Late Tertiary and Quaternary courses of the Delaware, Susquehanna, Potomac and York Rivers. Our study generates a detailed illustration of major river systems' paleochannel frequency, distribution and geometry and provides new insight into how coastal river systems evolve in low-gradient passive margins.

  2. The first historic record of a humpback whale (Megaptera novaeangliae) from the Low Countries (Southern Bight of the North Sea)

    OpenAIRE

    Haelters, J.; Kerckhof, F.; Camphuysen, K.C.J.

    2010-01-01

    In 1751 the corpse of a large whale was found floating at sea near Blankenberge (currently Belgium). The case was illustrated at the time by a water-colour of the whale and of an associated barnacle. In earlier publications, this whale has been regarded as a northern right whale (Eubalaena glacialis). However, morphological characteristics depicted in the original water-colour, published here for the first time, and in a copy of the original, point towards a humpback whale (Megaptera novaeang...

  3. NOAA TIFF Image - 10m Bathymetric Slope, South Atlantic Bight - Deep Coral Priority Areas - NOAA Ship Nancy Foster - (2007), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 10x10 meter cell size representing the slope (in degrees) of several deep coral priority areas off the South Atlantic...

  4. Turbidity, SOLAR RADIATION - ATMOSPHERIC and other data from UNKNOWN in the New York Bight and Long Island Sound from 1972-08-01 to 1973-09-20 (NODC Accession 9000039)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This accession consists of nutrient data from Long Island Sound provided by Mr. Robert N. Reid from NOAA/NMFS Sandy Hook Laboratory. The data were collected from...

  5. Physical trajectory profile data from glider ud_134 deployed by University of Delaware in the Mid-Atlantic Bight from 2016-08-30 to 2016-09-07 (NCEI Accession 0156682)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The scales of the sensing and prediction of bioluminescence represent a significant research challenge. Relevant scales range from 10s-1000s of meters and time...

  6. Physical trajectory profile data from glider ru28 deployed by Rutgers, the State University of New Jersey in the Mid-Atlantic Bight from 2016-09-01 to 2016-09-22 (NCEI Accession 0156659)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Deployment of a Slocum glider to perform surveys of dissolved oxygen concentrations in the shallow coastal waters of New Jersey. This dataset currently provides only...

  7. Current measurements from five ARGOS-tracked drifters in the Mid-Atlantic Bight, April 2003, in support of investigations of across-margin transport of biologically, geological, and chemically important materials (NODC Accession 0002346)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data collectors: Dr. Richard Garvine, University of Delaware, College of Marine Studies and Dr. Charles Tilburg, University of Georgia

  8. Current meter - direction and other data from FIXED PLATFORMS in support of the MESA New York Bight (MESA-NYB) project from 1979-04-03 to 1979-07-11 (NODC Accession 8000011)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Current meter - direction and other data were collected from FIXED PLATFORMS from 03 April 1979 to 11 July 1979. Data were collected by the National Ocean Service...

  9. Physical trajectory profile data from glider ru28 deployed by Rutgers, the State University of New Jersey in the Mid-Atlantic Bight from 2014-08-15 to 2014-09-05 (NCEI Accession 0145663)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Deployment to measure dissolved oxygen levels in the shallow coastal waters of New Jersey. The National Centers for Environmental Information (NCEI) received the...

  10. Physical trajectory profile data from glider ru28 deployed by Rutgers, the State University of New Jersey in the Mid-Atlantic Bight from 2016-07-14 to 2016-07-20 (NCEI Accession 0156658)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Deployment of a Slocum glider to perform surveys of dissolved oxygen concentrations in the shallow coastal waters of New Jersey. This dataset currently provides only...

  11. Physical trajectory profile data from glider ru28 deployed by Rutgers, the State University of New Jersey in the Mid-Atlantic Bight from 2013-08-16 to 2013-08-27 (NCEI Accession 0145660)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Deployment to measure dissolved oxygen levels in the shallow coastal waters of New Jersey. The National Centers for Environmental Information (NCEI) received the...

  12. Physical trajectory profile data from glider ru30 deployed by Rutgers, the State University of New Jersey in the Mid-Atlantic Bight from 2016-09-01 to 2016-09-26 (NCEI Accession 0156681)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Slocum glider dataset gathered as part of the TEMPESTS (The Experiment to Measure and Predict East coast STorm Strength), funded by NOAA through CINAR (Cooperative...

  13. Physical trajectory profile data from glider whoi_406 deployed by Woods Hole Oceanographic Institution in the Mid-Atlantic Bight from 2016-09-02 to 2016-09-20 (NCEI Accession 0156640)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Slocum glider dataset gathered as part of the TEMPESTS (The Experiment to Measure and Predict East coast STorm Strength), funded by NOAA through CINAR (Cooperative...

  14. Physical trajectory profile data from glider ru23 deployed by Rutgers, the State University of New Jersey in the Mid-Atlantic Bight from 2014-08-14 to 2014-09-06 (NCEI Accession 0137967)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — U.S. IOOS Mid-Atlantic Regional Consortium of Ocean Observing Systems (MARACOOS) glider deployment to survey the physical and biological properties of Mid-Atlantic...

  15. Physical trajectory profile data from glider ru23 deployed by Rutgers, the State University of New Jersey in the Mid-Atlantic Bight from 2013-03-05 to 2013-03-23 (NCEI Accession 0137964)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — U.S. IOOS Mid-Atlantic Regional Consortium of Ocean Observing Systems (MARACOOS) glider deployment to survey the physical and biological properties of Mid-Atlantic...

  16. Physical trajectory profile data from glider ru23 deployed by Rutgers, the State University of New Jersey in the Mid-Atlantic Bight from 2014-09-16 to 2014-09-29 (NCEI Accession 0137968)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — U.S. IOOS Mid-Atlantic Regional Consortium of Ocean Observing Systems (MARACOOS) glider deployment to survey the physical and biological properties of Mid-Atlantic...

  17. Physical trajectory profile data from glider blue deployed by University of Massachusetts; University of Massachusetts - Dartmouth in the Mid-Atlantic Bight from 2016-08-18 to 2016-08-22 (NCEI Accession 0156657)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — U.S. IOOS Mid-Atlantic Regional Association Coastal Ocean Observing System (MARACOOS) glider deployment. This is the second of a series of yearly seasonal...

  18. Physical trajectory profile data from glider ru23 deployed by Rutgers, the State University of New Jersey in the Mid-Atlantic Bight from 2015-10-08 to 2015-10-27 (NCEI Accession 0153545)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — U.S. IOOS Mid-Atlantic Regional Consortium of Ocean Observing Systems (MARACOOS) glider deployment to survey the physical and biological properties of Mid-Atlantic...

  19. Physical trajectory profile data from glider ru23 deployed by Rutgers, the State University of New Jersey in the Mid-Atlantic Bight from 2013-10-17 to 2013-11-06 (NCEI Accession 0137966)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — U.S. IOOS Mid-Atlantic Regional Consortium of Ocean Observing Systems (MARACOOS) glider deployment to survey the physical and biological properties of Mid-Atlantic...

  20. Physical trajectory profile data from glider ru32 deployed by Rutgers, the State University of New Jersey in the Mid-Atlantic Bight from 2016-08-10 to 2016-08-19 (NCEI Accession 0156390)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Deployment of a Slocum glider to perform surveys of dissolved oxygen concentrations in the shallow coastal waters of New Jersey. This dataset currently provides only...

  1. Physical trajectory profile data from glider ru28 deployed by Rutgers, the State University of New Jersey in the Mid-Atlantic Bight from 2015-09-17 to 2015-10-07 (NCEI Accession 0145711)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Deployment of a Slocum glider to perform surveys of dissolved oxygen concentrations in the shallow coastal waters of New Jersey. This dataset currently provides only...

  2. Physical trajectory profile data from glider ru28 deployed by Rutgers, the State University of New Jersey in the Mid-Atlantic Bight from 2015-08-18 to 2015-09-09 (NCEI Accession 0145710)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Deployment of a Slocum glider to perform surveys of dissolved oxygen concentrations in the shallow coastal waters of New Jersey. This dataset currently provides only...

  3. Current meter - direction and other data from FIXED PLATFORMS in support of the MESA New York Bight (MESA-NYB) project from 1976-11-30 to 1977-04-25 (NODC Accession 7700712)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Current meter - direction and other data were collected from FIXED PLATFORMS from 30 November 1976 to 25 April 1977. Data were collected by the National Ocean...

  4. HYDROCARBONS - TOTAL RESOLVED, CAS (CHEMICAL ABSTRACTS SERVICE) PARAMETER CODES and PCB, and other data from VARIOUS SMALL VESSELS in the New York Bight from 1984-06-24 to 1984-09-06 (NODC Accession 9100099)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data collected for the New York City Department Of Environmental Protection for submission to US Environmental Protection Agency as part of the application for...

  5. A comparison of observed extreme water levels at the German Bight elaborated through an extreme value analysis (EVA) with extremes derived from a regionally coupled ocean-atmospheric climate model (MPI-OM)

    Science.gov (United States)

    Möller, Jens; Heinrich, Hartmut

    2017-04-01

    As a consequence of climate change atmospheric and oceanographic extremes and their potential impacts on coastal regions are of growing concern for governmental authorities responsible for the transportation infrastructure. Highest risks for shipping as well as for rail and road traffic originate from combined effects of extremes of storm surges and heavy rainfall which sometimes lead to insufficient dewatering of inland waterways. The German Ministry of Transport and digital Infrastructure therefore has tasked its Network of Experts to investigate the possible evolutions of extreme threats for low lands and especially for Kiel Canal, which is an important shortcut for shipping between the North and Baltic Seas. In this study we present results of a comparison of an Extreme Value Analysis (EVA) carried out on gauge observations and values derived from a coupled Regional Ocean-Atmosphere Climate Model (MPI-OM). High water levels at the coasts of the North and Baltic Seas are one of the most important hazards which increase the risk of flooding of the low-lying land and prevents such areas from an adequate dewatering. In this study changes in the intensity (magnitude of the extremes) and duration of extreme water levels (above a selected threshold) are investigated for several gauge stations with data partly reaching back to 1843. Different methods are used for the extreme value statistics, (1) a stationary general Pareto distribution (GPD) model as well as (2) an instationary statistical model for better reproduction of the impact of climate change. Most gauge stations show an increase of the mean water level of about 1-2 mm/year, with a stronger increase of the highest water levels and a decrease (or lower increase) of the lowest water levels. Also, the duration of possible dewatering time intervals for the Kiel-Canal was analysed. The results for the historical gauge station observations are compared to the statistics of modelled water levels from the coupled atmosphere-ocean climate model MPI-OM for the time interval from 1951 to 2000. We demonstrate that for high water levels the observations and MPI-OM results are in good agreement, and we provide an estimate on the decreasing dewatering potential for Kiel Canal until the end of the 21st century.

  6. Physical trajectory profile data from glider blue deployed by University of Massachusetts; University of Massachusetts - Dartmouth in the Mid-Atlantic Bight from 2016-05-18 to 2016-06-06 (NCEI Accession 0153544)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — U.S. IOOS Mid-Atlantic Regional Association Coastal Ocean Observing System (MARACOOS) glider deployment. This is the first of a series of yearly seasonal deployments...

  7. Physical trajectory profile data from glider ru28 deployed by Rutgers, the State University of New Jersey in the Mid-Atlantic Bight from 2014-07-17 to 2014-08-06 (NCEI Accession 0145662)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Deployment to measure dissolved oxygen levels in the shallow coastal waters of New Jersey. The National Centers for Environmental Information (NCEI) received the...

  8. Physical trajectory profile data from glider ru28 deployed by Rutgers, the State University of New Jersey in the Mid-Atlantic Bight from 2013-09-12 to 2013-10-24 (NCEI Accession 0145661)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Deployment to measure dissolved oxygen levels in the shallow coastal waters of New Jersey. The National Centers for Environmental Information (NCEI) received the...

  9. Uncovering hidden biodiversity in the Cryptophyta: Clone library studies at the Helgoland Time Series Site in the Southern German Bight indentifies the cryptophycean clade potentially responsible for the majority of its genetic diversity during the spring bloom.

    Czech Academy of Sciences Publication Activity Database

    Medlin, L.K.; Piwosz, Kasia; Metfies, K.

    2017-01-01

    Roč. 67, č. 1 (2017), s. 27-32 ISSN 0240-8759 Institutional support: RVO:61388971 Keywords : CRYPTOPHYTES * DIVERSITY * PICOPHYTOPLANKTON Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 0.343, year: 2016

  10. Water physics and chemistry data from moored current meter and bottle casts in the Coastal Waters of New Jersey as part of the Mesa New York Bight (MESA - NYB) project, 09 April 1979 - 23 August 1979 (NODC Accession 8100440)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water physics and chemistry data were collected using moored current meter and bottle casts in the Coastal Waters of New Jersey from April 9, 1979 to August 23,...

  11. Multibeam Collection for Multibeam Mapping of the South Atlantic Bight: Georgia 2005, a Proposed MPA on the Continential Shelf on the R/V Cape Fear in the North Atlantic Ocean between June 13, 2005 and July 7, 2005

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Library Catalog may include: Data Management Plans, Cruise Plans, Cruise Summary Reports, Scientific "Quick Look Reports", Video Annotation Logs, Image Collections,...

  12. Nutrients, chlorophyll, and other data from Northeast Water Column Monitoring cruises in the Mid-Atlantic Bight for the Northeast Monitoring Program (NEMP), 21 April 1980 to 24 April 1984 (NODC Accession 8800171)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multiple cruise reports for the Northeast Monitoring Program (NEMP) describe the data collection activities, analyses and tabular data from multiple NEMP cruises in...

  13. NOAA TIFF Image - 50m Backscatter, Charleston Bump - Deep Coral Priority Areas - Nancy Foster - (2006), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the backscatter intensity of the Charleston Bump off of the South Atlantic Bight,...

  14. NOAA TIFF Image - 30m Rugosity, Charleston Bump - Deep Coral Priority Areas - Thomas Jefferson - (2007), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the bathymetry of the Charleston Bump off of the South Atlantic Bight, derived from...

  15. NOAA TIFF Image - 50m Rugosity, Charleston Bump - Deep Coral Priority Areas - Whiting - (2001), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 50x50 meter cell size representing the bathymetry of the Charleston Bump off of the South Atlantic Bight, derived from...

  16. NOAA TIFF Image - 50m Rugosity, Charleston Bump - Deep Coral Priority Areas - Whiting - (2000), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 50x50 meter cell size representing the bathymetry of the Charleston Bump off of the South Atlantic Bight, derived from...

  17. NOAA TIFF Image - 50m Backscatter, Charleston Bump - Deep Coral Priority Areas - NOAA Ship Thomas Jefferson - (2007), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the backscatter intensity of the Charleston Bump off of the South Atlantic Bight,...

  18. NOAA TIFF Image - 50m Singlebeam Slope, Charleston Bump - Deep Coral Priority Areas - Whiting - (2000), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 50x50 meter cell size representing the slope of the Charleston Bump off of the South Atlantic Bight, derived from...

  19. Primary Productivity (PP_Master)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set included primary production for each subregion in the study (Georges Bank, Gulf of Maine, Southern New England, Middle Atlantic Bight) . The data came...

  20. Wind_Speeds_Master

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set included wind speeds for each subregion in the study (Georges Bank, Gulf of Maine, Southern New England, Middle Atlantic Bight) . The data came from...

  1. Chlorophyll_Master

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set included chlorophyll for each subregion in the study (Georges Bank, Gulf of Maine, Southern New England, Middle Atlantic Bight) . The data came from...

  2. Turbidity, SOLAR RADIATION - ATMOSPHERIC and other data from NOAA Ship DELAWARE II in the Gulf of Mexico, NW Atlantic and other waters from 1991-01-04 to 1994-12-06 (NODC Accession 9600123)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Conductivity, Temperature and Depth (CTD) and other data were collected in Gulf of Mexico, Mid-Atlantic Bight, and NW Atlantic (limit-40 W) using NOAA Ship...

  3. PRESSURE - WATER and Other Data from EASTWARD and Other Platforms From Gulf of Mexico from 19750311 to 19770509 (NCEI Accession 8000017)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Microfiche publication of the Mississippi Delta Bight Studies, Offshore Primary Production (R/E-5), Louisiana Sea Grant Program, was submitted by R.E. Turner and...

  4. NOAA TIFF Image - 50m Multibeam Bathymetry, Charleston Bump - Deep Coral Priority Areas - Little Hales - (2003), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the bathymetry of the Charleston Bump off of the South Atlantic Bight, derived from...

  5. NOAA TIFF Image - 50m Singlebeam Bathymetry, Charleston Bump - Deep Coral Priority Areas - Whiting - (2000), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 50x50 meter cell size representing the bathymetry of the Charleston Bump off of the South Atlantic Bight, derived from...

  6. NOAA TIFF Image - 50m Multibeam Bathymetry, Charleston Bump - Deep Coral Priority Areas - Whiting - (2001), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 50x50 meter cell size representing the bathymetry of the Charleston Bump off of the South Atlantic Bight, derived from...

  7. NOAA TIFF Image - 30m Multibeam Bathymetry, Charleston Bump - Deep Coral Priority Areas - Nancy Foster - (2006), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the bathymetry of the Charleston Bump off of the South Atlantic Bight, derived from...

  8. NOAA TIFF Image - 50m Slope, Charleston Bump - Deep Coral Priority Areas - Whiting - (2001), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 50x50 meter cell size representing the bathymetry Bight, derived from data collected in 2001 by the of the Charleston...

  9. Analyses of otoliths from juvenile black sea bass collected from estuaries in SC, FL, NJ, and NY: 2008-2009.

    Data.gov (United States)

    Baruch Institute for Marine and Coastal Sciences, Univ of South Carolina — Snappers/Groupers have traditionally been some of the most desired demersal fishes in the South Atlantic Bight and are the most abundant and diverse group of large...

  10. Turbidity, SOLAR RADIATION - ATMOSPHERIC and other data from unknown platforms in the Bismarck Sea, Solomon Sea and other waters from 1990-07-01 to 1992-07-31 (NODC Accession 9500124)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Hydrology Bottle data in this accession was collected in Great Australian Bight as part of Global Ocean Data Archeaology and Rescue (GODAR) project from RV...

  11. NOAA's Web Service for the New York Offshore Biogeographic Assessment

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This web service provides key ecological data layers in the New York Bight via the Internet and which can be loaded into client side GIS software. The web service...

  12. Conductivity, temperature, depth, water quality and pigment data from R/V Bellows cruise BE-1311, 2012-12-12 to 2012-12-14 (NCEI Accession 0159411)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains conductivity, temperature, and depth data collected during R/V Bellows cruise BE-1311 of the offshore shelf of the Florida Panhandle Bight at...

  13. NOAA TIFF Image - 30m Rugosity, Charleston Bump - Deep Coral Priority Areas - Nancy Foster - (2006), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the 2006 multibeam bathymetry of the Charleston Bump off of the South Atlantic Bight,...

  14. NOAA TIFF Image - 30m Multibeam Bathymetry, Charleston Bump - Deep Coral Priority Areas - Thomas Jefferson - (2007), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the bathymetry of the Charleston Bump off of the South Atlantic Bight, derived from...

  15. NOAA TIFF Image - 30m Slope, Charleston Bump - Deep Coral Priority Areas - R/V Maurice Ewing - (1997), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the backscatter intensity of the Charleston Bump off of the South Atlantic Bight,...

  16. NOAA TIFF Image - 30m Backscatter, Charleston Bump - Deep Coral Priority Areas - NOAA Ship Thomas Jefferson - (2007), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the backscatter intensity of the Charleston Bump off of the South Atlantic Bight,...

  17. NOAA TIFF Image - 30m Rugosity, Charleston Bump - Deep Coral Priority Areas - R/V Maurice Ewing - (1997), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the backscatter intensity of the Charleston Bump off of the South Atlantic Bight,...

  18. CMS: Simulated Physical-Biogeochemical Data, SABGOM Model, Gulf of Mexico, 2005-2010

    Data.gov (United States)

    National Aeronautics and Space Administration — This dataset contains monthly mean ocean surface physical and biogeochemical data for the Gulf of Mexico simulated by the South Atlantic Bight and Gulf of Mexico...

  19. The Formation of Small Particles and Aggregates in the Rhine Estuary

    NARCIS (Netherlands)

    Eisma, D.; Kalf, J.; Veenhuis, M.

    1980-01-01

    Particulate matter in suspension in the Southern Bight of the North Sea consists mainly of more or less round, often loose aggregates (particles glued together with organic matter) and further of single mineral grains, some small (

  20. CTD, water quality, and phytoplankton data from the R/V Bellows cruise BE-1322 in the Gulf of Mexico from 2013-06-02 to 2013-06-04 (NCEI Accession 0161217)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains conductivity, temperature, and depth data from R/V Bellows cruise BE-1322 of the offshore shelf of the Florida Panhandle Bight at the head of...

  1. Delayed XBT data collected by Royal Australian Navy and submitted to NODC for the Global Temperature-Salinity Profile Program (GTSPP), dates range from January 18, 2011 to October 02, 2011 (NODC Accession 0086909)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profiles were collected from XBT casts in the Arafura Sea, Bass Strait, Coral Sea, Great Australian Bight, Gulf of Thailand, Indian ocean, South China...

  2. Delayed XBT data collected by the Royal Australian Navy and submitted to NODC for the Global Temperature-Salinity Profile Program (GTSPP), dates range from September 15 2009 to October 25 2010 (NODC Accession 0085726)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profiles were collected from XBT casts in the Great Australian Bight, Gulf of Thailand, Indian ocean, South China Sea, and Tasman Sea. Data were...

  3. Local habitat drivers of macrobenthos in the northern, central and ...

    African Journals Online (AJOL)

    Local habitat drivers of macrobenthos in the northern, central and southern KwaZulu-Natal Bight, South Africa. ... African Journal of Marine Science ... and bottom water physico-chemistry were determined at a significantly larger spatial scale.

  4. NYHOPS Forecast Model Results

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — 3D Marine Nowcast/Forecast System for the New York Bight NYHOPS subdomain. Currents, waves, surface meteorology, and water conditions.

  5. Current direction, bathythermograph (xbt), CTD, and other data from moored current meter casts and other instruments in the Gulf of Mexico during the Gulf of Mexico Physical Oceanography (GMPO) project, 1985-06-11 to 1986-09-03 (NODC Accession 8700196)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Current direction, bathythermograph (xbt), CTD, and other data were collected using moored current meter casts and other instruments in the Mid-Atlantic Bight and NW...

  6. EX1305: Summer Ecosystem Monitoring Survey on NOAA Ship Okeanos Explorer between 20130821 and 20130901

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The survey consists of 120 random stratified stations in the Middle Atlantic Bight, Southern New England, Georges Bank and the Gulf of Maine. Depending on the...

  7. Sediment toxicity data from stations in U.S. coastal waters from 19910318 to 19930303 (NCEI Accession 9400004)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The accession contains Sediment Toxicity data collected from Gulf of Mexico, Hudson Bay, New York Bight, North American Coastline-North, and Pamlico Sound as part of...

  8. Temperature and salinity profile data collected by the research vessels Agulhas and Meiring Naude off the southeast coast of Africa, April - July 1989 (NODC Accession 9400100)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Conductivity, Temperature and Depth (CTD) and other data were collected as part of MOES and Natal bight project in Prince Edward Islands. Data was collected from...

  9. Delayed XBT data collected by Royal Australian Navy and submitted to NODC for the Global Temperature-Salinity Profile Program (GTSPP), dates range from 2009-2011 (NODC Accession 0089585)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profiles were collected from XBT casts in the Arafura Sea, Bass Strait, Coral Sea, Great Australian Bight, Indian Ocean, Molukka Sea, North Pacific...

  10. CTD, water quality, and pigment data collected from R/V Bellows cruise BE-1317 in the Gulf of Mexico from 2013-04-06 to 2013-04-08 (NCEI Accession 0160919)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset reports conductivity, temperature, and depth data collected during R/V Bellows cruise BE-1317 of the offshore shelf of the Florida Panhandle Bight at...

  11. NOAA TIFF Image - 30m Rugosity, Charleston Bump - Deep Coral Priority Areas - R/V Maurice Ewing - (1997), UTM 17N NAD83

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains a unified GeoTiff with 30x30 meter cell size representing the bathymetry of the Charleston Bump off of the South Atlantic Bight, derived from...

  12. Initial studies of submarine groundwater discharge in Mississippi coastal waters

    Science.gov (United States)

    Shiller, A. M.; Moore, W. S.; Joung, D. J.; Box, H.; Ho, P.; Whitmore, L. M.; Gilbert, M.; Anderson, H.

    2017-12-01

    Submarine groundwater discharge (SGD) is a critical component of coastal ecosystems, affecting biogeochemistry and productivity. The SGD flux and effect on the ecosystem of the Mississippi (MS) Bight has not previously been studied. We have determined Ba, δ18O of water, and Ra-isotopes, together with nutrients, chlorophyll, and dissolved oxygen (DO) during multiple cruises from fall 2015 to summer 2016. Water isotope distributions (δ18O) show that, although the MS River Delta bounds the western side of the Bight, nonetheless, Mobile Bay and other local rivers are the Bight's dominant freshwater sources. But elevated dissolved Ba and Ra isotopes cannot be explained by river input. Spatially, SGD in the MS Bight occurs over a wide area, with hot spots near the barrier islands (e.g., Chandeleurs, Horn and Dauphin Islands) and the mouth of Mobile Bay, probably in association with old buried river channels, or dredged ship channels. Based on their high concentrations in saline groundwaters sampled on the barrier islands, the elevated Ba and Ra in MS Bight water are likely due to SGD. In subsurface waters, long-lived Ra isotopes were negatively correlated with DO during spring and summer 2016, suggesting direct discharge of DO-depleted groundwater and/or accumulation of SGD-derived Ra and microbial DO consumption under strongly stratified conditions. Our ongoing study suggests that seasonal variability in flushing, water stratification, and SGD input play important roles in biological production and bottom water hypoxia in the MS Bight.

  13. Water physics and chemistry data from moored current meter and bottle casts in the Coastal Waters of New Jersey as part of the Marine EcoSystems Analysis - New York Bight (MESA - NYB) project, 1973-08-27 to 1974-11-27 (NODC Accession 7600777)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water physics and chemistry data were collected using moored current meter and bottle casts in the Coastal Waters of New Jersey from August 27, 1973 to November 7,...

  14. Water physics and chemistry data from moored current meter and bottle casts in the Coastal Waters of New Jersey as part of the Mesa New York Bight (MESA - NYB) project, 1974-03-08 to 1974-05-13 (NODC Accession 7501210)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water physics and chemistry data were collected using moored current meter and bottle casts in the Coastal Waters of New Jersey from March 8, 1974 to May 13, 1974....

  15. Physical trajectory profile data from glider ru28 deployed by Rutgers, The State University of New Jersey; Center for Ocean Observing Leadership in the Mid-Atlantic Bight from 2017-04-24 to 2017-05-11 (NCEI Accession 0164191)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Deployment of a Slocum glider to perform surveys of dissolved oxygen concentrations in the shallow coastal waters of New Jersey. This deployment is part of the New...

  16. Chemical data from moored current meter, bottle casts, and other instruments in the Coastal Waters of New Jersey as part of the Mesa New York Bight (MESA - NYB) project, 1978-05-18 to 1978-10-19 (NODC Accession 7900280)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Chemical data were collected using moored current meter, bottle casts, and other instruments in the Coastal Waters of New Jersey from May 18, 1978 to October 19,...

  17. Water physics and chemistry data from moored current meter and bottle casts in the Coastal Waters of New Jersey as part of the Mesa New York Bight (MESA - NYB) project, 1963-05-21 to 1975-07-08 (NODC Accession 7601561)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water physics and chemistry data were collected using moored current meter and bottle casts in the Coastal Waters of New Jersey from May 21, 1963 to July 8, 1975....

  18. Physical trajectory profile data from glider ru28 deployed by Rutgers, The State University of New Jersey; Center for Ocean Observing Leadership in the Mid-Atlantic Bight from 2016-10-03 to 2016-10-17 (NCEI Accession 0162480)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Deployment of a Slocum glider to perform surveys of dissolved oxygen concentrations in the shallow coastal waters of New Jersey. This dataset currently provides only...

  19. Water physics and chemistry data from moored current meter and bottle casts in the Coastal Waters of New Jersey as part of the Mesa New York Bight (MESA - NYB) project, 1975-01-15 to 1975-12-08 (NODC Accession 7700136)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water physics and chemistry data were collected using moored current meter and bottle casts in the Coastal Waters of New Jersey from January 15, 1975 to December 8,...

  20. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from underway - surface observations using Carbon dioxide (CO2) gas analyzer, Shower head chamber equilibrator for autonomous carbon dioxide (CO2) measurement and other instruments from the SOUTHERN SURVEYOR in the Coral Sea, Great Australian Bight and others from 2011-04-06 to 2011-11-26 (NODC Accession 0115708)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115708 includes chemical, meteorological, physical and underway - surface data collected from SOUTHERN SURVEYOR in the Coral Sea, Great Australian...

  1. Origins of the deep-sea sediments and their variations with time. Annual progress report No. 6, May 1975

    International Nuclear Information System (INIS)

    Biscaye, P.E.

    1975-05-01

    Techniques for studying water mass mixing and sediment transport in the benthic layer of the deep sea and the effects of these processes on the continental shelf specifically in the New York Bight were studied. Results are presented for the first major combined geochemistry-physical oceanography cruise. Data on the nature of the bottom sediments are presented principally in context of their potential as sources of both radon and methane in the lower water column. Preliminary data on the nature and composition of suspended particulates also indicate potential for tracing the mechanisms of solids dispersal in the Bight. (PCS)

  2. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from time series observations using Bubble type equilibrator for autonomous carbon dioxide (CO2) measurement, Carbon dioxide (CO2) gas analyzer and other instruments from HERON ISLAND, KANGAROO ISLAND and others in the Coral Sea, Great Australian Bight and Tasman Sea from 2009-10-09 to 2012-11-28 (NODC Accession 0100062)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0100062 includes chemical, meteorological, physical and time series data collected from HERON ISLAND, KANGAROO ISLAND, MARIA ISLAND, MOORING_HERON...

  3. Ammonia, silicate, phosphate, nitrite+nitrate, dissolved oxygen, and other variables collected from profile and discrete sample observations using CTD, nutrient autoanalyzer, and other instruments from NOAA Ship Delaware II, NOAA Ship Gordon Gunter, NOAA Ship Henry B. Bigelow, NOAA Ship Okeanos Explorer, and NOAA Ship Pisces in the Gulf of Maine, Georges Bank, and Mid-Atlantic Bight from 2009-11-03 to 2016-08-19 (NCEI Accession 0127524)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains nutrient concentrations, temperature, salinity, density and dissolved oxygen values measured by CTD profiles on the U.S. Northeast Continental...

  4. Ocean waste disposal. Volume 2. 1977-July, 1978 (a bibliography with abstracts). Report for 1977-July 1978

    International Nuclear Information System (INIS)

    Brown, R.J.

    1978-07-01

    The majority of the cited topics cover the ocean disposal of sewage, sewage sludge, and dredged material, although reports on the disposal of radioactive wastes, brines, and industrial wastes are also included. The ecological affects are given, as is research on the pollution of the New York Bight. However, studies on the discharge of heated effluents are excluded

  5. 75 FR 55692 - Proposed Research Area Within the Gray's Reef National Marine Sanctuary

    Science.gov (United States)

    2010-09-14

    ... Georgia, Southeast Georgia Conference Center, 3700 Altama Avenue, Brunswick, GA. ADDRESSES: You may submit... accessible. Do not submit confidential business information or otherwise sensitive or protected information... Bight). GRNMS protects 16.68 square nautical miles of open ocean and submerged lands of particularly...

  6. Ocean waste disposal. A bibliography with abstracts. Search period covered 1964--May 1975

    International Nuclear Information System (INIS)

    1975-01-01

    The majority of the cited topics discuss the ocean disposal of sewage, sewage sludge, and dredged material, although reports on the disposal of radioactive wastes, brines, and industrial wastes are also covered. The ecological effects are included, as is research on the pollution of the New York Bight. However, studies on the discharge of heated effluents is excluded. Contains 164 abstracts. (auth)

  7. Distribution of diatom Pseudo-nitzschia and dinoflagellates of Dinophysis spp along coast off Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Alkawri, A.A.S.; Ramaiah, N.

    .A. Schaffner, B. Stauffer, B. Jones, S.B. Weisberg, P.M. DiGiacomo, W. Berelson and D.A. Caron: Blooms of Pseudo-nitzschia and domoic acid in the San Pedro Channel and Los Angeles harbor areas of the Southern California Bight, 2003-2004. Harmful Algae, 6, 372...

  8. 77 FR 29449 - Toyota Motor Corporation, Inc., Grant of Petition for Decision of Inconsequential Noncompliance

    Science.gov (United States)

    2012-05-17

    ... to consumers and would not impair a consumer's ability to locate the lower anchorages. (2) Paragraph... consumers' ability to find the LATCH anchorages. While anchor bars are permitted to be as short as 25 mm in... longitudinal vertical plane tangent to the side of the anchorage bar. If a person were to probe the seat bight...

  9. morphometric features of a low-elevation urban catchment

    African Journals Online (AJOL)

    PROF EKWUEME

    River basin morphometric is a geomorphological tool that applies to physical ... Harcourt region's drainage as it pertains to flooding described the area as ... floods in several sub-basins of a river that posed risks to ... Bight of Bonny, off the Gulf of Guinea into the Atlantic ..... the extreme; because such forest will be thick and.

  10. Phosphorus binding by poorly crystalline iron oxides in North Sea sediments

    NARCIS (Netherlands)

    Slomp, C.P.; Gaast, S. J. van der; Raaphorst, W. van

    1996-01-01

    Differential X-ray powder diffraction (DXRD) and extraction procedures were used to characterize the iron oxides present in four sediments from contrasting environments in the North Sea. Stations were located in depositional areas on the southern shelf (German Bight) and on the north-eastern

  11. analytical overview of agricultural conditions in nigeria

    African Journals Online (AJOL)

    PC USER

    2015-01-01

    Jan 1, 2015 ... Nigeria (fig.1) is bounded in the south by the Atlantic ... Guinea (Bights of Benin and Biafra); the inland frontiers .... Guinea savanna starts in the middle belt, or southern part ... The concept of land has been defined as the area.

  12. Benthic organic matter supply and metabolism at dispositional and non-depositional areas in the North Sea

    NARCIS (Netherlands)

    Boon, A.R.; Duineveld, G.C.A.; Kok, A.

    1999-01-01

    In 1994, four stations in the southern North Sea, the German Bight and the Skagerrak were visited with the aim to get insight into spatial and temporal variation in the supply of fresh organic matter to the benthos and its subsequent metabolic reaction. Stations were chosen on the basis of

  13. Enhanced benthic activity in sandy sublittoral sediments: Evidence from 13C tracer experiments

    NARCIS (Netherlands)

    Bühring, S.I.; Ehrenhauss, S.; Kamp, A.; Moodley, L.; Prof. Witte, U.

    2006-01-01

    In situ and on-board pulse-chase experiments were carried out on a sublittoral fine sand in the German Bight (southern North Sea) to investigate the hypothesis that sandy sediments are highly active and have fast turnover rates. To test this hypothesis, we conducted a series of experiments where we

  14. Undulator based scanning microscope at the National Synchrotron Light Source

    International Nuclear Information System (INIS)

    Rarback, H.; Shu, D.; Ade, H.; Jacobsen, C.; Kirz, J.; McNulty, I.; Rosser, R.

    1986-01-01

    A second generation scanning soft x-ray microscope is under construction, designed to utilize the dramatic increase in source bightness available at the soft x-ray undulator. The new instrument is expected to reduce image acquisition time by a factor of about 100, and to improve resolution, stability, and reproducibility

  15. Impact of salinity on the production of tomato along the coastal areas ...

    African Journals Online (AJOL)

    The coast of Benin lies on a wide bay in the Gulf of Guinea called the Bight of Benin, about 125 km between Togo and Nigeria. The coastal areas of Benin cover part of the cultivable lands of the country. A total of 15 tomato varieties were recorded in the areas of study. The characteristics of each variety grown under salinity ...

  16. Author Details

    African Journals Online (AJOL)

    Huggett, JA. Vol 19 (1998) - Articles Weekly variability of clupeoid eggs and larvae in the Benguela jet current: implications for recruitment. Abstract PDF · Vol 38, No 1s (2016): Supplementary - Articles Summer and winter differences in zooplankton biomass, distribution and size composition in the KwaZulu-Natal Bight, ...

  17. De invloed van predatie op de zomerafname van het herbivoor zooplankton in de Zuidelijke Bocht van de Noordzee

    NARCIS (Netherlands)

    Kuiters, L.

    1980-01-01

    Numerous predator species were found in the Southern Bight of the North Sea during the period June 18-July 26 (1979). Four subareas distinguished differed in predator density, assumingly due to the abundance of the Scyphomedusa Cyanea lamarckii in both coastal areas. It is not clear how the

  18. Saliniteit, nutriënten en planktonpigment in open zee en in de brandingszone van de Zuidelijke Bocht in voorjaar en zomer 1974

    NARCIS (Netherlands)

    Van Hattum, B.; de Voogt, P.; van Tilburg, P.

    1976-01-01

    The distribution of salinity and nutrients in the eastern part of the Southern Bight of the North Sea was compared with their distribution in a one mile wide area along the Dutch beach, called "beach-zone". A special sampling program was established, consisting of a general survey in the eastern

  19. Recent shoreline changes in the Volta River delta, West Africa: the ...

    African Journals Online (AJOL)

    Spit growth has been accompanied by a wave of erosion over the last century of the immediate downdrift sector of the bight coast, endangering the town of Keta. Erosion since the 1960s may have been aggravated by the construction of the Akosombo hydropower dam. The tip of the spit has recently welded to the shoreline, ...

  20. The Pleistocene reindeer of the North Sea - initial palaeontological data and archaeological remarks

    NARCIS (Netherlands)

    Glimmerveen, J; Mol, D; van der Plicht, H

    The interdisciplinary North Sea Project aims at investigating the biotic history of the Pleistocene in the Southern Bight of the North Sea. Humans were part of these biotopes too as Palaeolithic flint artefacts prove. Based on a large fossil record and radiocarbon dating, it becomes clear that

  1. Multi-year Current Observations on the Shelf Slope off Cape Hatteras, NC

    Science.gov (United States)

    Muglia, M.

    2017-12-01

    As part of an observing and modeling effort by the North Carolina Renewable Ocean Energy Program to determine if the Gulf Stream is a viable marine hydrokinetic energy resource for the state, upper continental slope current measurements were made over a period of nearly four years off of Cape Hatteras, NC. Velocity profiles were measured by a near-bottom, upward-looking, 150-kHz Acoustic Doppler Current Profiler deployed at a depth of 230-260 m. The mooring was sited at the location where water from the Gulf Stream, Middle Atlantic Bight, South Atlantic Bight, and Slope Sea all converge. Measured tidal amplitudes here are 2 m. These observations are used to consider the temporal variability and vertical structure of the currents at this location at tidal to interannual periods at this complex location. Concurrent near-bottom water mass properties are considered.

  2. Occurrence of contaminants of emerging concern along the California coast (2009-10) using passive sampling devices

    Science.gov (United States)

    Alvarez, David A.; Maruya, Keith A.; Dodder, Nathan G.; Lao, Wenjian; Furlong, Edward T.; Smalling, Kelly L.

    2014-01-01

    Three passive sampling devices (PSDs), polar organic chemical integrative samplers (POCIS), polyethylene devices (PEDs), and solid-phase microextraction (SPME) samplers were used to sample a diverse set of chemicals in the coastal waters of San Francisco Bay and the Southern California Bight. Seventy one chemicals (including fragrances, phosphate flame retardants, pharmaceuticals, PAHs, PCBs, PBDEs, and pesticides) were measured in at least 50% of the sites. The chemical profile from the San Francisco Bay sites was distinct from profiles from the sites in the Southern California Bight. This distinction was not due to a single compound or class, but by the relative abundances/concentrations of the chemicals. Comparing the PSDs to mussel (Mytilus spp.) tissues, a positive correlation exists for the 25 and 26 chemicals in common for the PEDs and SPME, respectively. Diphenhydramine was the only common chemical out of 40 analyzed in both POCIS and tissues detected at a common site.

  3. The Coastal Observing System for Northern and Arctic Seas (COSYNA)

    OpenAIRE

    Baschek, Burkard; Schroeder, Friedhelm; Brix, Holger; Riethmüller, Rolf; Badewien, Thomas H.; Breitbach, Gisbert; Brügge, Bernd; Colijn, Franciscus; Doerffer, Roland; Eschenbach, Christiane; Friedrich, Jana; Fischer, Philipp; Garthe, Stefan; Horstmann, Jochen; Krasemann, Hajo

    2017-01-01

    The Coastal Observing System for Northern and Arctic Seas (COSYNA) was established in order to better understand the complex interdisciplinary processes of northern seas and the Arctic coasts in a changing environment. Particular focus is given to the German Bight in the North Sea as a prime example of a heavily used coastal area, and Svalbard as an example of an Arctic coast that is under strong pressure due to global change. The COSYNA automated observing and modelling system is designed...

  4. National Guidebook for Application of Hydrogeomorphic Assessment to Tidal Fringe Wetlands

    Science.gov (United States)

    1998-12-01

    valleys, barrier islands, lagoons , fjords, and other coastal waterways; receive their water primarily from marine or estuarine sources; and are...range 1-3 m, e.g., the Georgia Bight) (3) Tidally restricted lagoons (e.g., Indian River Lagoon ) d. South Florida (Indian River, Florida, to Cedar...Organic constituents include plant detrital material, benthic micro- and macroinvertebrates , organic films, and animal fecal pellets (Kastler and

  5. SAR Product Improvements and Enhancements - SARprises

    Science.gov (United States)

    2013-09-30

    paper on current fields at Orkney, Scotland, was accepted for publication in IEEE - TGARS and is currently in press (available on IEEE Xplore as Early...Sea surface velocity vector retrieval using dual-beam interferometry: First demonstration, IEEE TGARS, 43, 2494- 2502, 2005. [2] Chapron, B., F...Bight by airborne along-track interferometric SAR, Proc. IGARSS 2002, 1822-1824, IEEE , 2002. [4] Bjerklie, D.M., S.L. Dingman, C.J. Vorosmarty, C.H

  6. Ocean waste disposal (a bibliography with abstracts). Report for 1964--Jun 1976

    International Nuclear Information System (INIS)

    Brown, R.J.

    1976-07-01

    The majority of the cited topics discuss the ocean disposal of sewage, sewage sludge, and dredged material, although reports on the disposal of radioactive wastes, brines and industrial wastes are also covered. The ecological affects are included as is research on the pollution of the New York Bight. However, studies on the discharge of heated effluents are excluded. (This updated bibliography contains 231 abstracts, 67 of which are new entries to the previous edition.)

  7. Caractéristiques ecohydrodynamiques de la Baie Sud de la Mer du Nord en régime d'été

    OpenAIRE

    Hecq, J.H.; Mingelbier, M.; Goffart, A.; Brylinski, J.-M.; Djendi, S.

    1992-01-01

    On the basis of the hydrological context, an optimal sarnpling network bas been set up to obtain a synoptic picture of temperature. Salinity, nutrients, chlorophyll and zooplankton distributions in the Southem Bight of the North Sea. The data confirm the general tendency of isolines to be para11el to the coast. The plankton distribution shows the influence of Scheldt water farer to the south-west than proposed by previous models and observations.

  8. Sediment-water chemical exchange in the coastal zone traced by in situ radon-222 flux measurements

    International Nuclear Information System (INIS)

    Martens, C.S.; Kipphut, G.W.; Klump, J.V.

    1980-01-01

    In situ radon-222 flux experiments conducted in benthic chambers in Cape Lookout Bight, a small marine basin on the North Carolina coast, reveal that enhanced chemical transport across the sediment-water interface during summer months is caused by abiogenic bubble tube structures. Transport rates for dissolved radon, methane, and ammonium more than three times greater than those predicted on the basis of molecular diffusion occur when open tubes are maintained by semidiurnal low-tide bubbling

  9. Relationship Between Physical and Biological Properties on the Microscale: A Cross-Comparison Between Differing Coastal Domains

    Science.gov (United States)

    2013-09-01

    persistent layers of particulate matter (defined by turbidity or chlorophyll); DISTRIBUTION STATEMENT A. Approved for public release; distribution...mesoscale physical processes on thin zooplankton layers at four sites along the west coast of the U.S. Estuaries and Coasts. 30: 575-590 Dekshenieks...Nash and J.N. Moum (2013), Stratification and mixing regimes in biological thin layers over the Mid- Atlantic bight, submitted to Limnol. Oceanogr

  10. New perspectives on Natal Pulses from satellite observations

    CSIR Research Space (South Africa)

    Rouault, MJ

    2011-07-01

    Full Text Available that on their journey from the Natal Bight to Port Elizabeth, Natal Pulses systematically interact with the coastal topography to generate upstream perturbations. These upstream offshore meanders occur when the trailing edge of the original Natal Figure 2. SST daily... SST which have a relatively low tem- poral resolution (daily) can also prove difficult due to the extensive and persistent cloud coverage above the Agulhas Current [Rouault et al., 2000]. [5] High�frequency data acquisitions from the geostation...

  11. Water type quantification in the Skagerrak, the Kattegat and off the Jutland west coast

    Directory of Open Access Journals (Sweden)

    Trond Kristiansen

    2015-04-01

    Full Text Available An extensive data series of salinity, nutrients and coloured dissolved organic material (CDOM was collected in the Skagerrak, the northern part of the Kattegat and off the Jutland west coast in April each year during the period 1996–2000, by the Institute of Marine Research in Norway. In this month, after the spring bloom, German Bight Water differs from its surrounding waters by a higher nitrate content and higher nitrate/phosphate and nitrate/silicate ratios. The spreading of this water type into the Skagerrak is of special interest with regard to toxic algal blooms. The quantification of the spatial distributions of the different water types required the development of a new algorithm for the area containing the Norwegian Coastal Current, while an earlier Danish algorithm was applied for the rest of the area. From the upper 50 m a total of 2227 observations of salinity and CDOM content have been used to calculate the mean concentration of water from the German Bight, the North Sea (Atlantic water, the Baltic Sea and Norwegian rivers. The Atlantic Water was the dominant water type, with a mean concentration of 79%, German Bight Water constituted 11%, Baltic Water 8%, and Norwegian River Water 2%. At the surface the mean percentages of these water types were found to be 68%, 15%, 15%, and 3%, respectively. Within the northern part of the Skagerrak, closer to the Norwegian coast, the surface waters were estimated to consist of 74% Atlantic Water, 20% Baltic Water, and 7% Norwegian River Water. The analysis indicates that the content of German Bight Water in this part is less than 5%.

  12. Atlantic Coastal Experiment VI: R/V KNORR cruise, 23 August--11 September 1980, data report

    Energy Technology Data Exchange (ETDEWEB)

    Behrens, W.; von Bock, K. (eds)

    1983-01-01

    An investigation of the influence of estuaries on the ecosystem of the Mid-Atlantic Bight was undertaken. Data were collected from excursions into the Hudson, Delaware and Chesapeake estuaries, three across-shelf and one along-shelf transects, and two time series stations. In all, 139 stations were occupied and 164 XBT soundings were taken. In addition to standard hydrographic measurements, nutrient , chlorophyll, particulate carbon and nitrogen, 14C, 15N, DNA, particle size, FTD, phytoplankton and zooplankton analyses were made.

  13. Marine ecoregion and Deepwater Horizon oil spill affect recruitment and population structure of a salt marsh snail

    Science.gov (United States)

    Pennings, Steven C.; Zengel, Scott; Oehrig, Jacob; Alber, Merryl; Bishop, T. Dale; Deis, Donald R.; Devlin, Donna; Hughes, A. Randall; Hutchens, John J.; Kiehn, Whitney M.; McFarlin, Caroline R.; Montague, Clay L.; Powers, Sean P.; Proffitt, C. Edward; Rutherford, Nicolle; Stagg, Camille L.; Walters, Keith

    2016-01-01

    Marine species with planktonic larvae often have high spatial and temporal variation in recruitment that leads to subsequent variation in the ecology of benthic adults. Using a combination of published and unpublished data, we compared the population structure of the salt marsh snail, Littoraria irrorata, between the South Atlantic Bight and the Gulf Coast of the United States to infer geographic differences in recruitment and to test the hypothesis that the Deepwater Horizon oil spill led to widespread recruitment failure of L. irrorata in Louisiana in 2010. Size-frequency distributions in both ecoregions were bimodal, with troughs in the distributions consistent with a transition from sub-adults to adults at ~13 mm in shell length as reported in the literature; however, adult snails reached larger sizes in the Gulf Coast. The ratio of sub-adults to adults was 1.5–2 times greater in the South Atlantic Bight than the Gulf Coast, consistent with higher recruitment rates in the South Atlantic Bight. Higher recruitment rates in the South Atlantic Bight could contribute to higher snail densities and reduced adult growth in this region. The ratio of sub-adults to adults in Louisiana was lower in 2011 than in previous years, and began to recover in 2012–2014, consistent with widespread recruitment failure in 2010, when large expanses of spilled oil were present in coastal waters. Our results reveal an important difference in the ecology of a key salt marsh invertebrate between the two ecoregions, and also suggest that the Deepwater Horizon oil spill may have caused widespread recruitment failure in this species and perhaps others with similar planktonic larval stages.

  14. Bolsa Bay, California, Proposed Ocean Entrance System Study. Report 2. Comprehensive Shoreline Response Computer Simulation, Bolsa Bay, California

    Science.gov (United States)

    1990-04-01

    Southern California Bight is affected by a land-sea breeze pattern. A variation in flow is caused by the heating of the land surface during the day, and...1980). 27. The success of the inlet channel at Agua Hedionda indicates that a stable non-navigable entrance at Bolsa Chica could be feasible provided a...dual jetty system similar to Agua Hedionda is incorporated into the design. However, structures that penetrate into the active surf zone are expected

  15. A multi-level adaptation model of circulation for the western Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Shaji, C.; Bahulayan, N.; Dube, S.K.; Rao, A.D.

    and diffusion terms in the momentum equations and also in the resultant vorticity balance. The results of the calculation indicated realistic climatological Gulf Stream behaviour in the South Atlantic Bight. Sarmiento and Bryan [7] also developed a robust... be balanced. In case the volume flux or the velocities are not balanced, appropriate corrections should be applied to the velocity fields at the boundary so that the velocities are balanced to the maximum extent possible. We have used a quasi-geostrophic model...

  16. On action- and affectpsychology of human reliability. An access by training simulators for complex man-machine systems

    International Nuclear Information System (INIS)

    Schuette, M.

    2002-02-01

    Theoretical part and its topics: errors at the interface between man and machine; reliability analysis for man; the psychological explanation of action reliability of man (intention and control); a paradigma for human reliability (frustration and regression). Empirical part: Control room in a nuclear power plant: Influences on repeated blockages on component care in case of start-up operation; ship bridge: Frustration and regression while steering in a bight. Appendix: analysis of a social interaction.(GL)

  17. KONTUR - research vessel 'Meteor' voyage No. 58

    International Nuclear Information System (INIS)

    KONTUR strategy is to provide different types of measurements simultaneously: (i) a radiosonde network to provide the mean meteorological field, especially divergences and baroclinicity, (ii) air-craft missions to study convection as well as turbulence, and (iii) tethered ballon and surface equipment to provide vertical profiles of turbulent quantities throughout the atmospheric boundary layer. The experiment is carried out in the area of the German Bight. (orig./HP) [de

  18. Optical measurements in the North Sea-Baltic Sea transition zone. I. On the origin of the deep water in the Kattegat

    Science.gov (United States)

    Højerslev, N. K.; Holt, N.; Aarup, T.

    1996-08-01

    In the North Sea-Baltic Sea region, several studies have shown that yellow substance can be treated as a quasi-conservative parameter that is negatively correlated with salinity. A review of more than 5000 historic and recently gathered yellow substance absorption and salinity measurements from the transition zone between the North Sea and the Baltic Sea have been analyzed for the purpose of water mass identification. Salinity-yellow substance scatter plots show that three water masses can be identified in the area: (1) North Sea water (high salinity, low yellow substance content); (2) Baltic Sea water (low salinity, intermediate-high yellow substance content); and (3) German Bight/Southern North Sea water (intermediate-high salinity, high yellow substance content). Based on the volume flow estimates used in a two-layer box-model of the Kattegat (Jørgensen, Continental Shelf Research, 12, 103-114, 1992) and conservation of yellow substance, it is argued that the long-term average composition of the bottom layer inflow to the Kattegat from the Skagerrak consists of about 90% North Sea/Atlantic water and 10% German Bight/Southern North Sea water. The German Bight content estimate is substantially lower than the ones given in earlier studies (50-67%) and implies that the Jutland Coastal Current only has a small impact on the water quality of the Kattegat.

  19. Seasonal Variation of Harbor Seal's Diet from the Wadden Sea in Relation to Prey Availability.

    Directory of Open Access Journals (Sweden)

    Camille de la Vega

    Full Text Available The Wadden Sea has an important role for marine mammals in terms of resting, nursing and foraging. Harbor seal is the most abundant marine mammal species in this area. The use of the food resources of the Wadden Sea by seals is not clear, and previous studies showed that this species can travel kilometers away from their haul-outs to forage in the North Sea. In this study, we analyzed the stable isotopes of vibrissae from 23 dead harbor seals found on the island of Sylt to investigate their diet. The predator´s carbon and nitrogen isotope compositions were compared to the compositions of different potential prey items from the Sylt-Rømø Bight and from the North Sea in order to study seasonal pattern in the diet and in the foraging location. In parallel, seasonal variation of abundance and biomass of the potential prey items from the Sylt-Rømø Bight were studied and compare to their contribution to the seal´s diet. The results revealed a change in the seal´s diet from pelagic sources in spring to a benthic based diet in summer, and an increasing use of the North Sea resources in fall and winter in accordance with the seasonal variation of the availability of prey in the Sylt-Rømø Bight.

  20. SOSIAL EKONOMI PEREMPUAN MIGRAN KEMBALI (RETURN MIGRANT JORONG KAPUH, NAGARI SUMANI, KAB. SOLOK

    Directory of Open Access Journals (Sweden)

    Yuliana Nengrum

    2014-06-01

    Full Text Available Marantau is a tradition in Minangkabaunes. Such as with Jorong Kapuh society it is economic factor and behavior as support their to do it. In the bight economic factor homogeny and less economic to get daily want until 70% in that condition. The aims based on resolution of the problem are: first, to describe a woman knowledge about bight, second, to describe the reason a woman can do it, third, to describe the reason a woman as a brighter and return migrant, fourth, to describe economic social condition us return migrant. Research counducted with qualitative approach with descriptive method. Informant chosed using purposive. The result of this research conclusion of bight woman is studied, couple research, socialization with another society. Social economic condition have two differences variable, first, economic variable (their physic necessity, health for economic physic, second, social variable (long life need, the appreciate of society, help another, success in their life. Merantau merupakan tradisi masyarakat Minangkabau. Demikian halnya dengan masyarakat Jorong Kapuh, selain dari merantau menjadi suatu tradisi faktor ekonomi dan keadaan alam juga sebagai pendorong bagi masyarakat Jorong Kapuh untuk merantau. Berdasarkan rumusan masalah terdapat empat tujuan penelitian yaitu: pertama, mendeskripsikan pengetahuan perempuan tentang merantau, kedua, mendeskripsikan alasan perempuan merantau, ketiga, mendeskripsikan alasan perempuanperantau, kembali kekampunghalamannya, keempat, mendeskripsikan kondisi sosiale konomi perempuan perantau pasca migrasi sebagai migrant kembali. Penelitian dilakukan dengan pendekatan kualitatif dengan metode penelitian deskriptif. Teknik pengambilan informan dilakukan dengancara purposive sampling. Hasil dari penelitian ini, dapat disimpulkan bahwa perempuan merantau yaitu mencari pengalaman hidup, perubahan ekonomi yang lebih baik, mencari jodoh, menuntut ilmu, bersosialisasi dengan masyarakat di rantau. Kondisi

  1. Modelling the fate of the Tijuana River discharge plume

    Science.gov (United States)

    van Ormondt, M.; Terrill, E.; Hibler, L. F.; van Dongeren, A. R.

    2010-12-01

    After rainfall events, the Tijuana River discharges excess runoff into the ocean in a highly turbid plume. The runoff waters contain large suspended solids concentrations, as well as high levels of toxic contaminants, bacteria, and hepatitis and enteroviruses. Public health hazards posed by the effluent often result in beach closures for several kilometers northward along the U.S. shoreline. A Delft3D model has been set up to predict the fate of the Tijuana River plume. The model takes into account the effects of tides, wind, waves, salinity, and temperature stratification. Heat exchange with the atmosphere is also included. The model consists of a relatively coarse outer domain and a high-resolution surf zone domain that are coupled with Domain Decomposition. The offshore boundary conditions are obtained from the larger NCOM SoCal model (operated by the US Navy) that spans the entire Southern California Bight. A number of discharge events are investigated, in which model results are validated against a wide range of field measurements in the San Diego Bight. These include HF Radar surface currents, REMUS tracks, drifter deployments, satellite imagery, as well as current and temperature profile measurements at a number of locations. The model is able to reproduce the observed current and temperature patterns reasonably well. Under calm conditions, the model results suggest that the hydrodynamics in the San Diego Bight are largely governed by internal waves. During rainfall events, which are typically accompanied by strong winds and high waves, wind and wave driven currents become dominant. An analysis will be made of what conditions determine the trapping and mixing of the plume inside the surfzone and/or the propagation of the plume through the breakers and onto the coastal shelf. The model is now also running in operational mode. Three day forecasts are made every 24 hours. This study was funded by the Office of Naval Research.

  2. Invasion of Asian tiger shrimp, Penaeus monodon Fabricius, 1798, in the western north Atlantic and Gulf of Mexico

    Science.gov (United States)

    Fuller, Pam L.; Knott, David M.; Kingsley-Smith, Peter R.; Morris, James A.; Buckel, Christine A.; Hunter, Margaret E.; Hartman, Leslie D.

    2014-01-01

    After going unreported in the northwestern Atlantic Ocean for 18 years (1988 to 2006), the Asian tiger shrimp, Penaeus monodon, has recently reappeared in the South Atlantic Bight and, for the first time ever, in the Gulf of Mexico. Potential vectors and sources of this recent invader include: 1) discharged ballast water from its native range in Asia or other areas where it has become established; 2) transport of larvae from established non-native populations in the Caribbean or South America via ocean currents; or 3) escape and subsequent migration from active aquaculture facilities in the western Atlantic. This paper documents recent collections of P. monodon from the South Atlantic Bight and the Gulf of Mexico, reporting demographic and preliminary phylogenetic information for specimens collected between North Carolina and Texas from 2006 through 2012. The increased number of reports in 2011 and 2012, ranging from 102 mm to 298 mm total length, indicates that an adult population is present in densities sufficient for breeding, which is indicative of incipient establishment. Based on these reports of P. monodon, its successful invasion elsewhere, and its life history, we believe that this species will become common in the South Atlantic Bight and Gulf of Mexico in less than 10 years. Penaeus monodon is an aggressive predator in its native range and, if established, may prey on native shrimps, crabs, and bivalves. The impacts of an established P. monodon population are potentially widespread (e.g., alterations in local commercial fisheries, direct and indirect pressures on native shrimp, crab and bivalve populations, and subsequent impacts on the populations of other predators of those organisms) and should be considered by resource managers. The impacts of P. monodon on native fauna and the source(s) or vector(s) of the invasion, however, remain unknown at this time.

  3. Contaminants and nutrients in variable sea areas (Canvas). Application of automatic monitoring stations in the German marine environment

    International Nuclear Information System (INIS)

    Nies, H.; Bruegge, B.; Sterzenbach, D.; Knauth, H.D.; Schroeder, F.

    1999-01-01

    Permanent observation of parameters at sea stations can only be obtained by automatic sampling. The MERMAID technique developed in former projects provides a possibility to run automatic stations within the German MARNET measuring stations to obtain data on nutrients concentration on line and to collect organic micropollutants and the radionuclide 137 Cs by solid phase extraction from seawater and subsequent analysis in the laboratory. The BSH MARNET consists of ten stations located in the German Bight sector of the North Sea and the western Baltic. First results from the time series of nutrient and organic micropollutant concentrations has been presented

  4. Fate of nuclides in natural water systems. Annual progress report, October 1, 1978-September 30, 1979

    International Nuclear Information System (INIS)

    Turekian, K.K.

    1979-01-01

    Results of estuarine and coastal studies in the Long Island Sound and the New York Bight areas are summarized briefly. 234 Th and 228 Th were used to determine the residence time of thorium in the water column as a function of distance from the Long Island-New Jersey coast. Results indicate that virtually all of the 234 Th is taken to the sediment column on a very short time scale. Paths for the redistribution of metals in the sediment column are outlined. Studies on the sources and properties of organic carbon delivered to the estuarine systems are reviewed briefly

  5. CHEMTAX-derived phytoplankton community structure associated with temperature fronts in the northeastern Arabian Sea..

    Digital Repository Service at National Institute of Oceanography (India)

    Roy, R; Chitari, R; Kulkarni, V.; Krishna, M.S.; Sarma, V.V.S.S.; Anil, A.C.

    and northern Arabian Sea. Deep-Sea Res. I 34, 713-723. Barlow, R., Kyewalyanga, M., Sessions, H., Van den Berg, M., Morris, T., 2008. Phytoplankton pigments, functional types, and absorption properties in the Delagoa and Natal Bights of the Agulhas... for Prochlorococcus sp. in low-light suboxic environments in the Arabian Sea and the Eastern Tropical North Pacific. Deep-Sea Res. I. 47, 1183-1205. Grasshoff, K., Erhardt, M., Kremiling, K., 1983. Methods of seawater analysis, Verlag Chemie. 419 Haynes, R...

  6. Distribution of the early larval stages of cod, plaice and lesser sandeel across haline fronts in the North Sea

    DEFF Research Database (Denmark)

    Munk, Peter; Wright, P.J.; Pihl, Niels Jørgen

    2002-01-01

    A number of commercially important fish species spawn in the coastal areas of the North Sea in the late winter, including cod (Gadus morhua), plaice (Pleuronectes platessa) and lesser sandeel (Ammodytes marinus). The distribution of the early stages of these species overlap to some extent...... Influence (ROFI), predominantly in the Dogger Bank and German Bight areas. There was a high degree of overlap between the distributions of cod and plaice, while the maximal abundance of lesser sandeel was found inshore of the other species. Larval distributions were to a large extent confined by the frontal...

  7. Atlantic Coastal experiment III, FRV Delaware II cruise, 17-27 May 1977 and R/V ONRUST cruise, 28-30, June 1977. Data report

    Energy Technology Data Exchange (ETDEWEB)

    Malloy, S.; Stoddard, A.; von Bock, K. (eds.)

    1980-09-01

    The DELAWARE II and ONRUST cruises, continuations of Atlantic Coastal Experiment III, were made during May and late June, 1977, to compare seasonal changes in chlorophyll a, nitrogen nutrient, dissolved oxygen and phytoplankton composition within the mid-Atlantic and New York Bights. Data from 106 stations and 3300 km of surface mapping are reported as classical hydrographic listings, areal and/or vertical contours of chlorophyll a, inorganic nitrogen and salinity, and listings of phytoplankton species abun- dance. Temperature profiles from 100 stations are included, as well as res- piration experiments [ETS assay] for the dinoflagellate, Ceratium tripos.

  8. Illuminating cancer health disparities using ethnogenetic layering (EL) and phenotype segregation network analysis (PSNA).

    Science.gov (United States)

    Jackson, Fatimah L C

    2006-01-01

    Resolving cancer health disparities continues to befuddle simplistic racial models. The racial groups alluded to in biomedicine, public health, and epidemiology are often profoundly substructured. EL and PSNA are computational assisted techniques that focus on microethnic group (MEG) substructure. Geographical variations in cancer may be due to differences in MEG ancestry or similar environmental exposures to a recognized carcinogen. Examples include breast and prostate cancers in the Chesapeake Bay region and Bight of Biafra biological ancestry, hypertension and stroke in the Carolina Coast region and Central African biological ancestry, and pancreatic cancer in the Mississippi Delta region and dietary/medicinal exposure to safrol from Sassafras albidum.

  9. 210Pb and 210Po as tracers of particle transport mechanisms on continental margins

    International Nuclear Information System (INIS)

    Radakovitch, O.; Heussner, S.; Biscaye, P.; Abassi, A.

    1997-01-01

    The natural radionuclides 210 Po and 210 Pb, members of the 238 U decay chain, are particularly helpful to the understanding of particle transport processes in the ocean. These isotopes were analysed on sediment trap particles collected during 3 one-year experiments on continental margins. In the Bay of Biscay (Northeastern Atlantic) and in the Gulf of Lion (Northwestern Mediterranean Sea) both as part of the French ECOMARGE programme, and in the Middle Atlantic Bight (Northwestern Atlantic) as part of the SEEP programme. They yielded great insights into scenarios of particle transfer at each site, mainly based on the spatial and temporal distribution of 210 Pb particulate concentrations and fluxes. (author)

  10. Chromophoric dissolved organic matter export from U.S. rivers

    Science.gov (United States)

    Spencer, Robert G. M.; Aiken, George R.; Dornblaser, Mark M.; Butler, Kenna D.; Holmes, R. Max; Fiske, Greg; Mann, Paul J.; Stubbins, Aron

    2013-04-01

    Chromophoric dissolved organic matter (CDOM) fluxes and yields from 15 major U.S. rivers draining an assortment of terrestrial biomes are presented. A robust relationship between CDOM and dissolved organic carbon (DOC) loads is established (e.g., a350 versus DOC; r2 = 0.96, p CDOM yields are also correlated to watershed percent wetland (e.g. a350; r2 = 0.81, p CDOM export from ungauged watersheds. A large variation in CDOM yields was found across the rivers. The two rivers in the north-eastern U.S. (Androscoggin and Penobscot), the Edisto draining into the South Atlantic Bight, and some rivers draining into the Gulf of Mexico (Atchafalaya and Mobile) exhibit the highest CDOM yields, linked to extensive wetlands in these watersheds. If the Edisto CDOM yield is representative of other rivers draining into the South Atlantic Bight, this would result in a CDOM load equivalent to that of the Mississippi from a region of approximately 10% of the Mississippi watershed, indicating the importance of certain regions with respect to the role of terrigenous CDOM in ocean color budgets.

  11. Trace metal fluxes to ferromanganese nodules from the western Baltic Sea as a record for long-term environmental changes

    Energy Technology Data Exchange (ETDEWEB)

    Hlawatsch, S.; Garbe-Schonberg, C.D.; Lechtenberg, F.; Manceau, A.; Tamura, N.; Kulik, D.A.; Suess, E.; Kersten, M.

    2002-03-12

    Trace element profiles in ferromanganese nodules from the western Baltic Sea were analyzed with laser ablation inductively coupled plasma mass spectroscopy (LA-ICP-MS) and synchrotron-based micro-X-ray radiation techniques (fluorescence: mSXRF, and diffraction: mXRD) at high spatial resolution in growth direction. Of the trace elements studied (Zn, Cu, Cd, Ni, Co, Mo, Ba), Zn showed the most significant enrichment, with values in the outermost surface layers of up to six-fold higher than those found in older core parts. The high-resolution Zn profiles provide the necessary temporal resolution for a dating method analogous to dendrochronology. Profiles in various samples collected during two decades were matched and the overlapping sections used for estimation of the accretion rates. Assuming a continuous accretion of these relatively fast growing nodules (on average 20 mm a-1) over the last century, the Zn enrichment was thus assessed to have commenced around 1860/70 in nodules from the Kiel Bight and in 1880/90 from Mecklenburg Bight, reflecting the enhanced heavy metal emissions with rising industrialization in Europe. Apart from the obvious success with Zn, only As and Co show significant but only 1.5-fold enrichments in the most recent growth layers of the nodules. Other anthropogenic trace metals like Cu and Cd are not at all enriched, which, together with the distinct early-diagenetic Fe/Mn banding, weakens the potential of the nodules for retrospective monitoring.

  12. Decadal Declines of Mercury in Adult Bluefish (1972-2011) from the Mid-Atlantic Coast of the U.S.A.

    Science.gov (United States)

    Cross, Ford A; Evans, David W; Barber, Richard T

    2015-08-04

    Concentrations of total mercury were measured in muscle of adult bluefish (Pomatomus saltatrix) collected in 2011 off North Carolina and compared with similar measurements made in 1972. Concentrations of mercury decreased by 43% in the fish between the two time periods, with an average rate of decline of about 10% per decade. This reduction is similar to estimated reductions of mercury observed in atmospheric deposition, riverine input, seawater, freshwater lakes, and freshwater fish across northern North America. Eight other studies between 1973 and 2007 confirm the decrease in mercury levels in bluefish captured in the Mid-Atlantic Bight. These findings imply that (1) reductions in the release of mercury across northern North America were reflected rather quickly (decades) in the decline of mercury in adult bluefish; (2) marine predatory fish may have been contaminated by anthropogenic sources of mercury for over 100 years; and (3) if bluefish are surrogates for other predators in the Mid-Atlantic Bight, then a reduction in the intake of mercury by the fish-consuming public has occurred. Finally, with global emissions of mercury continuing to increase, especially from Asia, it is important that long-term monitoring programs be conducted for mercury in marine fish of economic importance.

  13. Interdisciplinary approach to the demography of Jamaica.

    Science.gov (United States)

    Deason, Michael L; Salas, Antonio; Newman, Simon P; Macaulay, Vincent A; St A Morrison, Errol Y; Pitsiladis, Yannis P

    2012-02-23

    The trans-Atlantic slave trade dramatically changed the demographic makeup of the New World, with varying regions of the African coast exploited differently over roughly a 400 year period. When compared to the discrete mitochondrial haplotype distribution of historically appropriate source populations, the unique distribution within a specific source population can prove insightful in estimating the contribution of each population. Here, we analyzed the first hypervariable region of mitochondrial DNA in a sample from the Caribbean island of Jamaica and compared it to aggregated populations in Africa divided according to historiographically defined segments of the continent's coastline. The results from these admixture procedures were then compared to the wealth of historic knowledge surrounding the disembarkation of Africans on the island. In line with previous findings, the matriline of Jamaica is almost entirely of West African descent. Results from the admixture analyses suggest modern Jamaicans share a closer affinity with groups from the Gold Coast and Bight of Benin despite high mortality, low fecundity, and waning regional importation. The slaves from the Bight of Biafra and West-central Africa were imported in great numbers; however, the results suggest a deficit in expected maternal contribution from those regions. When considering the demographic pressures imposed by chattel slavery on Jamaica during the slave era, the results seem incongruous. Ethnolinguistic and ethnographic evidence, however, may explain the apparent non-random levels of genetic perseverance. The application of genetics may prove useful in answering difficult demographic questions left by historically voiceless groups.

  14. Chromophoric dissolved organic matter export from U.S. rivers

    Science.gov (United States)

    Spencer, Robert G. M.; Aiken, George R.; Dornblaser, Mark M.; Butler, Kenna D.; Holmes, R. Max; Fiske, Greg; Mann, Paul J.; Stubbins, Aron

    2013-01-01

    Chromophoric dissolved organic matter (CDOM) fluxes and yields from 15 major U.S. rivers draining an assortment of terrestrial biomes are presented. A robust relationship between CDOM and dissolved organic carbon (DOC) loads is established (e.g., a350 versus DOC; r2 = 0.96, p CDOM yields are also correlated to watershed percent wetland (e.g. a350; r2 = 0.81, p CDOM export from ungauged watersheds. A large variation in CDOM yields was found across the rivers. The two rivers in the north-eastern U.S. (Androscoggin and Penobscot), the Edisto draining into the South Atlantic Bight, and some rivers draining into the Gulf of Mexico (Atchafalaya and Mobile) exhibit the highest CDOM yields, linked to extensive wetlands in these watersheds. If the Edisto CDOM yield is representative of other rivers draining into the South Atlantic Bight, this would result in a CDOM load equivalent to that of the Mississippi from a region of approximately 10% of the Mississippi watershed, indicating the importance of certain regions with respect to the role of terrigenous CDOM in ocean color budgets.

  15. Do Continental Shelves Act as an Atmospheric CO2 Sink?

    Science.gov (United States)

    Cai, W.

    2003-12-01

    Recent air-to-sea CO2 flux measurements at several major continental shelves (European Atlantic Shelves, East China Sea and U.S. Middle Atlantic Bight) suggest that shelves may act as a one-way pump and absorb atmospheric CO2 into the ocean. These observations also favor the argument that continental shelves are autotrophic (i.e., net production of organic carbon, OC). The U.S. South Atlantic Bight (SAB) contrasts these findings in that it acts as a strong source of CO2 to the atmosphere while simultaneously exporting dissolved inorganic carbon (DIC) to the open ocean. We report pCO2, DIC, and alkalinity data from the SAB collected in 8 cruises along a transect from the shore to the shelf break in the central SAB. The shelf-wide net heterotrophy and carbon exports in the SAB are subsidized by the export of OC from the abundant intertidal marshes, which are a sink for atmospheric CO2. It is proposed here that the SAB represents a marsh-dominated heterotrophic ocean margin as opposed to river-dominated autotrophic margins. To further investigate why margins may behave differently in term of CO2 sink/source, the physical and biological conditions of several western boundary current margins are compared. Based on this and other studies, DIC export flux from margins to the open ocean must be significant in the overall global ocean carbon budget.

  16. Trace metal fluxes to ferromanganese nodules from the western Baltic Sea as a record for long-term environmental changes

    International Nuclear Information System (INIS)

    Hlawatsch, S.; Garbe-Schonberg, C.D.; Lechtenberg, F.; Manceau, A.; Tamura, N.; Kulik, D.A.; Suess, E.; Kersten, M.

    2002-01-01

    Trace element profiles in ferromanganese nodules from the western Baltic Sea were analyzed with laser ablation inductively coupled plasma mass spectroscopy (LA-ICP-MS) and synchrotron-based micro-X-ray radiation techniques (fluorescence: mSXRF, and diffraction: mXRD) at high spatial resolution in growth direction. Of the trace elements studied (Zn, Cu, Cd, Ni, Co, Mo, Ba), Zn showed the most significant enrichment, with values in the outermost surface layers of up to six-fold higher than those found in older core parts. The high-resolution Zn profiles provide the necessary temporal resolution for a dating method analogous to dendrochronology. Profiles in various samples collected during two decades were matched and the overlapping sections used for estimation of the accretion rates. Assuming a continuous accretion of these relatively fast growing nodules (on average 20 mm a-1) over the last century, the Zn enrichment was thus assessed to have commenced around 1860/70 in nodules from the Kiel Bight and in 1880/90 from Mecklenburg Bight, reflecting the enhanced heavy metal emissions with rising industrialization in Europe. Apart from the obvious success with Zn, only As and Co show significant but only 1.5-fold enrichments in the most recent growth layers of the nodules. Other anthropogenic trace metals like Cu and Cd are not at all enriched, which, together with the distinct early-diagenetic Fe/Mn banding, weakens the potential of the nodules for retrospective monitoring

  17. One Dimensional Backstripping Results from IODP Expedition 318, Site U1356: Tectonic Implications for the Wilkes Land Margin of Antarctica

    Science.gov (United States)

    Hayden, T. G.; Kominz, M. A.; González, J. J.; Escutia, C.; Brinkhuis, H.; Scientific Party of IODP Expedition 318

    2011-12-01

    The Wilkes Land margin of Antarctica is the conjugate margin of the Great Australian Bight, which underwent extension, thinning and rifting from ~160 Ma until breakup at ~83 Ma. Both Wilkes Land and the Great Australian Bight are considered passive margins, and were thought to be tectonically inactive since breakup at 83 Ma. We have backstripped the U1356 Core recovered from the continental rise off Wilkes Land, Antarctica by IODP Expedition 318. Backstripping input included lithological and sedimentary analysis, paleo-environmental indicators, combined paleomagnetic and biostratigraphic chronologies, and physical properties measurements. Tectonic subsidence shows a major event between 50 and 33.6 Ma, a time represented by a hiatus in the U1356 core. The magnitude of subsidence requires it to be tectonic in origin, and the timing matches with a reorganization of plate motions that represents the transition from slow spreading to fast spreading between Antarctica and Australia, which occurred at approximately 43 Ma. Coupled with a regional seismic framework, and using other Expedition 318 site analyses, the Wilkes Land margin is shown to be far more complex then the simple passive margin currently assumed. We explore several possible mechanisms for the subsidence and erosion observed; including thermal uplift due to continental insulation of the asthenosphere and it's interaction with a recently rifted margin, asthenospheric convection, transtensional or transpressional basin development and loading, and edge-driven asthenospheric convection.

  18. Meteo-marine parameters for highly variable environment in coastal regions from satellite radar images

    Science.gov (United States)

    Pleskachevsky, A. L.; Rosenthal, W.; Lehner, S.

    2016-09-01

    The German Bight of the North Sea is the area with highly variable sea state conditions, intensive ship traffic and with a high density of offshore installations, e.g. wind farms in use and under construction. Ship navigation and the docking on offshore constructions is impeded by significant wave heights HS > 1.3 m. For these reasons, improvements are required in recognition and forecasting of sea state HS in the range 0-3 m. Thus, this necessitates the development of new methods to determine the distribution of meteo-marine parameters from remote sensing data with an accuracy of decimetres for HS. The operationalization of these methods then allows the robust automatic processing in near real time (NRT) to support forecast agencies by providing validations for model results. A new empirical algorithm XWAVE_C (C = coastal) for estimation of significant wave height from X-band satellite-borne Synthetic Aperture Radar (SAR) data has been developed, adopted for coastal applications using TerraSAR-X (TS-X) and Tandem-X (TD-X) satellites in the German Bight and implemented into the Sea Sate Processor (SSP) for fully automatic processing for NRT services. The algorithm is based on the spectral analysis of subscenes and the model function uses integrated image spectra parameters as well as local wind information from the analyzed subscene. The algorithm is able to recognize and remove the influence of non-sea state produced signals in the Wadden Sea areas such as dry sandbars as well as nonlinear SAR image distortions produced by e.g. short wind waves and breaking waves. Also parameters of very short waves, which are not visible in SAR images and produce only unsystematic clutter, can be accurately estimated. The SSP includes XWAVE_C, a pre-filtering procedure for removing artefacts such as ships, seamarks, buoys, offshore constructions and slicks, and an additional procedure performing a check of results based on the statistics of the whole scene. The SSP allows an

  19. Photographs of the Sea floor Offshore of New York and New Jersey

    Science.gov (United States)

    Butman, Bradford; Gutierrez, Benjamin T.; Buchholtz ten Brink, Marilyn R.; Schwab, William S.; Blackwood, Dann S.; Mecray, Ellen L.; Middleton, Tammie J.

    2003-01-01

    This DVD-ROM contains photographs of the sea floor and sediment texture data collected as part of studies carried out by the U.S. Geological Survey (USGS) in the New York Bight (Figure 1a (PDF format)). The studies were designed to map the sea floor (Butman, 1998, URL: http://pubs.usgs.gov/fs/fs133-98/) and to develop an understanding of the transport and long-term fate of sediments and associated contaminants in the region (Mecray and others, 1999, URL: http://pubs.usgs.gov/fs/fs114-99/). The data were collected on four research cruises carried out between 1996 and 2000 (Appendix I). The images and texture data were collected to provide direct observations of the sea floor geology and to aid in the interpretation of backscatter intensity data obtained from sidescan sonar and multibeam surveys of the sea floor. Preliminary descriptions of the sea floor geology in this region may be found in Schwab and others (2000, URL: http://pubs.usgs.gov/of/of00-295/; 2003), Butman and others (1998, URL: http://pubs.usgs.gov/of/of98-616/.), and Butman and others (2002, URL: http://pubs.usgs.gov/of/of00-503/). Schwab and others (2000 URL: http://pubs.usgs.gov/of/of00-295/; 2003) have identified 11 geologic units in New York Bight (Figure 2 (PDF format)). These units identify areas of active sediment transport, extensive anthropogenic influence on the sea floor, and various geologic units. Butman and others (2003) and Harris and others (in press) present the results of a moored array experiment carried out in the Hudson Shelf Valley to investigate the transport of sediments during winter. Summaries of these and other studies may be found at USGS studies in the New York Bight (URL: http://woodshole.er.usgs.gov/project-pages/newyork/). This DVD-ROM contains digital images of bottom still photographs, images digitized from videos, sediment grain-size analysis results, and short QuickTime movies from video transects. The data are presented in tabular form and in an ESRI (Environmental

  20. Controls of multi-modal wave conditions in a complex coastal setting

    Science.gov (United States)

    Hegermiller, Christie; Rueda, Ana C.; Erikson, Li H.; Barnard, Patrick L.; Antolinez, J.A.A.; Mendez, Fernando J.

    2017-01-01

    Coastal hazards emerge from the combined effect of wave conditions and sea level anomalies associated with storms or low-frequency atmosphere-ocean oscillations. Rigorous characterization of wave climate is limited by the availability of spectral wave observations, the computational cost of dynamical simulations, and the ability to link wave-generating atmospheric patterns with coastal conditions. We present a hybrid statistical-dynamical approach to simulating nearshore wave climate in complex coastal settings, demonstrated in the Southern California Bight, where waves arriving from distant, disparate locations are refracted over complex bathymetry and shadowed by offshore islands. Contributions of wave families and large-scale atmospheric drivers to nearshore wave energy flux are analyzed. Results highlight the variability of influences controlling wave conditions along neighboring coastlines. The universal method demonstrated here can be applied to complex coastal settings worldwide, facilitating analysis of the effects of climate change on nearshore wave climate.

  1. An evaluation of the concept of assimilative capacity as applied to marine waters

    International Nuclear Information System (INIS)

    Krom, M.D.

    1986-01-01

    The concept of assimilative capacity has been suggested as a basis for permitting the controlled disposal of anthropogenic wastes in the ocean. It is suggested in this study that the term assimilative is a misnomer since there is no benefit for the receiving body of water from the addition of pollutants. The term accommodative capacity (AC) is suggested in its place. This procedure has been applied to the disposal of radioactive wastes, mercury and bacteria. In addition, two examples where the AC approach has been extended to the overall health of the ecosystem are considered: PCB's in the New York Bight and the disposal of sewage effluent off the coast of Southern California. From these examples, three schemes are put forward to implement the concept of AC on the basis of a) public health considerations, b) effects on the marine ecosystem and c) experimental strategies

  2. The effects of environmental parameters on zooplankton assemblages in tropical coastal estuary, South-west, Nigeria

    Directory of Open Access Journals (Sweden)

    Waidi O. Abdul

    2016-09-01

    Full Text Available The present study was carried out to examine the distribution and assemblage structure of zooplankton in relation to environmental parameters of tropical coastal estuarine ecosystem impounding Bight of Benin, Nigeria. The estuarine water samples were collected between January and December, 2014 from three sampling zones (Brushpark, Open water and Wetland then were fixed in 4% formalin. A total of twenty-eight (28 species belonging to four (4 groups were recorded in this study. These groups were rotifera, copepoda, cladocerans and ostracodas, and were all widely distributed in the three investigated zones. Higher richness, dominance and abundance indices were recorded in Zone I when compared to both Zones II and III. Cluster analysis showed five distinct species communities. The canonical correspondence analysis (CCA showed a distinct smattering positive and negative correlation on the distribution of zooplankton indicating that the relative abundance of any species was dependent on specific environmental variables.

  3. The "Tsunami Earthquake" of 13 April 1923 in Northern Kamchatka: Seismological and Hydrodynamic Investigations

    Science.gov (United States)

    Salaree, Amir; Okal, Emile A.

    2018-04-01

    We present a seismological and hydrodynamic investigation of the earthquake of 13 April 1923 at Ust'-Kamchatsk, Northern Kamchatka, which generated a more powerful and damaging tsunami than the larger event of 03 February 1923, thus qualifying as a so-called "tsunami earthquake". On the basis of modern relocations, we suggest that it took place outside the fault area of the mainshock, across the oblique Pacific-North America plate boundary, a model confirmed by a limited dataset of mantle waves, which also confirms the slow nature of the source, characteristic of tsunami earthquakes. However, numerical simulations for a number of legitimate seismic models fail to reproduce the sharply peaked distribution of tsunami wave amplitudes reported in the literature. By contrast, we can reproduce the distribution of reported wave amplitudes using an underwater landslide as a source of the tsunami, itself triggered by the earthquake inside the Kamchatskiy Bight.

  4. Detecting relationships between the interannual variability in climate records and ecological time series using a multivariate statistical approach - four case studies for the North Sea region

    Energy Technology Data Exchange (ETDEWEB)

    Heyen, H. [GKSS-Forschungszentrum Geesthacht GmbH (Germany). Inst. fuer Gewaesserphysik

    1998-12-31

    A multivariate statistical approach is presented that allows a systematic search for relationships between the interannual variability in climate records and ecological time series. Statistical models are built between climatological predictor fields and the variables of interest. Relationships are sought on different temporal scales and for different seasons and time lags. The possibilities and limitations of this approach are discussed in four case studies dealing with salinity in the German Bight, abundance of zooplankton at Helgoland Roads, macrofauna communities off Norderney and the arrival of migratory birds on Helgoland. (orig.) [Deutsch] Ein statistisches, multivariates Modell wird vorgestellt, das eine systematische Suche nach potentiellen Zusammenhaengen zwischen Variabilitaet in Klima- und oekologischen Zeitserien erlaubt. Anhand von vier Anwendungsbeispielen wird der Klimaeinfluss auf den Salzgehalt in der Deutschen Bucht, Zooplankton vor Helgoland, Makrofauna vor Norderney, und die Ankunft von Zugvoegeln auf Helgoland untersucht. (orig.)

  5. Atmospheric input of trace substances into the North Sea and the Baltic Sea. Stoffeintrag in Nord- und Ostsee ueber die Atmosphaere

    Energy Technology Data Exchange (ETDEWEB)

    Grassl, H; Eppel, D; Petersen, G; Schneider, B; Weber, H; Gandrass, J; Reinhardt, K H; Wodarg, D; Fliess, J

    1989-01-01

    The concentrations and deposition of atmospheric trace substances were measured over the Kiel Bight and the Southern North Sea. A European longrange-transport model was used to calculate the atmospheric concentrations of trace metals and their deposition into the North Sea and the Baltic Sea. Natural and anthropogenic emitted element concentrations could be separated definitely by the measurements, and preferred transport directions of anthropogenic contributions could be found. Concentrations measured over the North Sea could be related to the surrounding emission areas by airmass trajectory analyses. The deposition measurements show that the main removal process is due to deposition by precipitation. Calculated and measured concentrations at several receptor points agreed well. The model results confirm the dominating role of wet deposition. It could be shown that extrapolations from measurements at coastal stations to the whole sea area tend to overestimate the total deposition into North Sea and Baltic Sea. (orig.) With 78 refs., 26 tabs., 85 figs.

  6. Nearshore transport processes affecting dilution and fate of energy-related contaminants. Final report, 8 August 1977-30 September 1979

    International Nuclear Information System (INIS)

    Blanton, J.O.

    1979-01-01

    This report summarizes the findings and work completed under contract DE-AS09-77SR01025-3. The principal efforts consisted of (1) editing, analysis and plotting of oceanographic data obtained at the Savannah River Navigational Light Tower (SNLT), (2) the synthesis of data from a pilot experiment on transport of trace elements, and (3) the planning of an autumn 1979 experiment. The final report is organized into products that show what was done on these three tasks plus additional smaller tasks specified in Appendix A of the contract. Data are presented from the following specific subject areas: (1) oceanographic and meteorologial data 15 km off the coast of Georgia; (2) oceanographic and meteorological data from Savannah Navigational Light Tower: 9-11 May 1978 Experiment; (3) data report on sea level fluctuations in the South Atlantic Bight; (4) oceanographic and meteorological data 15 km off the coast of Georgia

  7. Transport and transfer rates in the waters of the continental shelf. Annual report

    International Nuclear Information System (INIS)

    Biscaye, P.E.; Broecker, W.S.; Feely, H.W.; Gerard, R.D.

    1976-04-01

    The report is to the Energy Research and Development Administration on accomplishments of the Lamont-Doherty Geological Observatory geochemistry and physical oceanography groups during the 1975-1976 funding period on grant E(11-1)2185. Goals are to obtain detailed, quantitative knowledge of the rates of mixing within coastal waters of the New York Bight and across the continental slope and the exchange of water masses and species transported within them between shelf and Atlantic Ocean waters. The research is aimed at understanding the chemical, physical, and biological processes which control the origin, dispersal, and fate of particulate matter and trace metals, and to ultimately model the impact of energy related pollutants on the continental shelf

  8. Enhanced benthic activity in sandy sublittoral sediments: Evidence from 13C tracer experiments

    DEFF Research Database (Denmark)

    Bühring, Solveig I.; Ehrenhauss, Sandra; Kamp, Anja

    2006-01-01

    In situ and on-board pulse-chase experiments were carried out on a sublittoral fine sand in the German Bight (southern North Sea) to investigate the hypothesis that sandy sediments are highly active and have fast turnover rates. To test this hypothesis, we conducted a series of experiments where we...... investigated the pathway of settling particulate organic carbon through the benthic food web. The diatom Ditylum brightwellii was labelled with the stable carbon isotope 13C and injected into incubation chambers. On-board incubations lasted 12, 30 and 132 h, while the in situ experiment was incubated for 32 h....... The study revealed a stepwise short-term processing of a phytoplankton bloom settling on a sandy sediment. After the 12 h incubation, the largest fraction of recovered carbon was in the bacteria (62%), but after longer incubation times (30 and 32 h in situ) the macrofauna gained more importance (15 and 48...

  9. The impact of temperature change on the activity and community composition of sulfate-reducing bacteria in arctic versus temperate marine sediments

    DEFF Research Database (Denmark)

    Robador, Alberto; Brüchert, Volker; Jørgensen, Bo Barker

    2009-01-01

    Arctic regions may be particularly sensitive to climate warming and, consequently, rates of carbon mineralization in warming marine sediment may also be affected. Using long-term (24 months) incubation experiments at 0°C, 10°C and 20°C, the temperature response of metabolic activity and community...... composition of sulfate-reducing bacteria were studied in the permanently cold sediment of north-western Svalbard (Arctic Ocean) and compared with a temperate habitat with seasonally varying temperature (German Bight, North Sea). Short-term 35S-sulfate tracer incubations in a temperature-gradient block...... (between -3.5°C and +40°C) were used to assess variations in sulfate reduction rates during the course of the experiment. Warming of arctic sediment resulted in a gradual increase of the temperature optima (Topt) for sulfate reduction suggesting a positive selection of psychrotolerant/mesophilic sulfate...

  10. Increase in dimethylsulfide (DMS emissions due to eutrophication of coastal waters offsets their reduction due to ocean acidification.

    Directory of Open Access Journals (Sweden)

    Nathalie eGypens

    2014-04-01

    Full Text Available Available information from manipulative experiments suggested that the emission of dimethylsulfide (DMS would decrease in response to the accumulation of anthropogenic CO2 in the ocean (ocean acidification. However, in coastal environments, the carbonate chemistry of surface waters was also strongly modified by eutrophication and related changes in biological activity (increased primary production and change in phytoplankton dominance during the last 50 years. Here, we tested the hypothesis that DMS emissions in marine coastal environments also strongly responded to eutrophication in addition to ocean acidification at decadal timescales. We used the R-MIRO-BIOGAS model in the eutrophied Southern Bight of the North Sea characterized by intense blooms of Phaeocystis that are high producers of dimethylsulfoniopropionate (DMSP, the precursor of DMS. We showed that, for the period from 1951 to 2007, eutrophication actually led to an increase of DMS emissions much stronger than the response of DMS emissions to ocean acidification.

  11. {sup 210}Pb and {sup 210}Po as tracers of particle transport mechanisms on continental margins

    Energy Technology Data Exchange (ETDEWEB)

    Radakovitch, O.; Heussner, S. [Perpignan Univ., 66 (France). Lab. de Sedimentologie et Geochimie Marines; Biscaye, P.; Abassi, A. [Columbia Univ., Palisades, NY (United States). Lamont Doherty Earth Observatory

    1997-12-31

    The natural radionuclides {sup 210}Po and {sup 210}Pb, members of the {sup 238}U decay chain, are particularly helpful to the understanding of particle transport processes in the ocean. These isotopes were analysed on sediment trap particles collected during 3 one-year experiments on continental margins. In the Bay of Biscay (Northeastern Atlantic) and in the Gulf of Lion (Northwestern Mediterranean Sea) both as part of the French ECOMARGE programme, and in the Middle Atlantic Bight (Northwestern Atlantic) as part of the SEEP programme. They yielded great insights into scenarios of particle transfer at each site, mainly based on the spatial and temporal distribution of {sup 210}Pb particulate concentrations and fluxes. (author) 11 refs.

  12. Vertical activity distribution of dissimilatory nitrate reduction in coastal marine sediments

    DEFF Research Database (Denmark)

    Behrendt, A.; de Beer, D.; Stief, P.

    2013-01-01

    The relative importance of two dissimilatory nitrate reduction pathways, denitrification (DEN) and dissimilatory nitrate reduction to ammonium (DNRA), was investigated in intact sediment cores from five different coastal marine field sites (Dorum, Aarhus Bight, Mississippi Delta, Limfjord...... reduction was clearly dominated by DEN (59-131% of the total NO3- reduced) rather than by DNRA, irrespective of the sedimentary inventories of electron donors such as organic carbon, sulfide, and iron. Highest ammonium production via DNRA, accounting for up to 8.9% of the total NO3- reduced, was found...... was detected accounting for 37-77% of the total NO3- reduced. These contradictory results might be explained by enhanced NO3- availability for DNRA bacteria in the sediment slurries compared to the core-incubated sediments in which diffusion of NO3- from the water column may only reach DEN bacteria...

  13. GEM 10B Satellite gravity data and Nigerian oil prospects

    International Nuclear Information System (INIS)

    Garde, S.C.; Kim, W.Y.

    1984-11-01

    Extension of the hydrocarbon rich Benue depression and the Niger delta basin in the bight of Benin is construed from the gravity data of Gravity Earth Model (GEM) 10B Satellite, published by NASA, Godard Space Flight Centre in 1977. This interpretation is based on the supposition that: i) the depth of a buried horizontal cylinder can be estimated by the Fourier transform of the vertical gravity field [Odegard and Berg, Geophys., 30, No. 3, 424-438 (1965)]; and ii) the oil horizons of southern Nigeria are basically connected to the separation of South American and African plates [Burke et al., African Geology, Ibadan Univ. Press, Ibadan, Nigeria, p. 187-204 (1970)]. (author)

  14. Subsurface seeding of surface harmful algal blooms observed through the integration of autonomous gliders, moored environmental sample processors, and satellite remote sensing in southern California

    KAUST Repository

    Seegers, Bridget N.

    2015-04-01

    An observational study was performed in the central Southern California Bight in Spring 2010 to understand the relationship between seasonal spring phytoplankton blooms and coastal processes that included nutrient input from upwelling, wastewater effluent plumes, and other processes. Multi-month Webb Slocum glider deployments combined with MBARI environmental sample processors (ESPs), weekly pier sampling, and ocean color data provided a multidimensional characterization of the development and evolution of harmful algal blooms (HABs). Results from the glider and ESP observations demonstrated that blooms of toxic Pseudo-nitzschia sp. can develop offshore and subsurface prior to their manifestation in the surface layer and/or near the coast. A significant outbreak and surface manifestation of the blooms coincided with periods of upwelling, or other processes that caused shallowing of the pycnocline and subsurface chlorophyll maximum. Our results indicate that subsurface populations can be an important source for “seeding” surface Pseudo-nitzschia HAB events in southern California.

  15. Trace metal fronts in European shelf waters

    International Nuclear Information System (INIS)

    Kremling, K.

    1983-01-01

    The Hebrides shelf edge area is characterized by strong horizontal salinity gradients (fronts) which mark the boundary between Scottish coastal and oceanic waters. The results presented here, obtained in summer 1981 on a transect between the open north Atlantic and the German Bight, confirm that the hydrographical front is accompanied by dramatic increases in inorganic nutrients (phosphate, silicate) and dissolved trace elements such as Cd, Cu, Mn, and 226 Ra. These data (together with measurements from North Sea regions) suggest that the trace metals are mobilized from partly reduced (organic-rich) sediments and vertically mixed into the surface waters. The regional variations evident from the transect are interpreted as being the result of the hydrography prevailing in waters around the British Isles. (author)

  16. A numerical model investigation of the formation and persistence of an erosion hotspot

    Science.gov (United States)

    Hansen, Jeff E.; Elias, Edwin; List, Jeffrey H.; Barnard, Patrick L.

    2011-01-01

    A Delft3D-SWAN coupled flow and wave model was constructed for the San Francisco Bight with high-resolution at 7 km-long Ocean Beach, a high-energy beach located immediately south of the Golden Gate, the sole entrance to San Francisco Bay. The model was used to investigate tidal and wave-induced flows, basic forcing terms, and potential sediment transport in an area in the southern portion of Ocean Beach that has eroded significantly over the last several decades. The model predicted flow patterns that were favorable for sediment removal from the area and net erosion from the surf-zone. Analysis of the forcing terms driving surf-zone flows revealed that wave refraction over an exposed wastewater outfall pipe between the 12 and 15 m isobaths introduces a perturbation in the wave field that results in erosion-causing flows. Modeled erosion agreed well with five years of topographic survey data from the area.

  17. Historical polycyclic aromatic and petrogenic hydrocarbon loading in Northern Central Gulf of Mexico shelf sediments.

    Science.gov (United States)

    Overton, E B; Ashton, B M; Miles, M S

    2004-10-01

    The distribution of selected hydrocarbons within ten dated sediment cores taken from the Mississippi River Bight off coastal Louisiana suggests a chronic contaminant loading from several sources including the river itself, oil and gas exploration in the central Gulf of Mexico (GOM) shelf area, and natural geologic hydrocarbon seeps. Data were grouped as either total polycyclic aromatic hydrocarbons (PAH's), which were indicative of pyrogenic PAH's; or estimated total hopanes (indicative of petrogenic hydrocarbons). The total PAH concentrations and estimated total hopanes begin increasing above background levels (approximately 200 ng g(-1)) after the 1950s. The distribution of these hydrocarbons and hopanes within the dated sediment cores suggests that the Mississippi River is a regional source of pyrogenic PAH's, and that the hopanes are from natural geologic hydrocarbon seeps, oil and gas exploration in the GOM, or both.

  18. The population dynamics of the parasitic copepode Lernaeocera lusci (Bassett-Smith, 1896) on its definitive host

    Science.gov (United States)

    van Damme, P. A.; Hamerlynck, O.; Ollevier, F.

    1996-06-01

    The mesoparasitic copepod Lernaeocera lusci (Bassett-Smith, 1896) was recovered from first-year bib ( Trisopterus luscus L.) in the Voordelta (Southern Bight of the North Sea) from May until December 1989. Analysis of the seasonal abundance and of the population structure showed that transmission of infective stages to bib mainly occurred from June to September. From September to December the overall prevalence fluctuated around 70%. Maximum parasite population size (47/104m2) and the highest total egg number were recorded in September and October, respectively. It was found that total parasite mortality was significantly influenced by mortality of hosts carrying parasites. Natural mortality probably contributed a small percentage to total parasite mortality. Calculation of the temporal mean-variance regression equation revealed that the parasites were aggregated within the definitive host population.

  19. Contesting "Le corps militaire": Antimilitarism, Pacificism, Anarcho-Communism and 'Le Douanier' Rousseau's La Guerre

    Directory of Open Access Journals (Sweden)

    Brauer, Fae

    2012-07-01

    Full Text Available When the 1889 Military Law was passed, it established three-year universal conscription and a greater army of citizens to boost military preparedness for war in French colonies and against Germany.Far from its ramifications being of no concern to neo-impressionists, it was the subject of bightingly bitter antimilitarist cartoons by Maximilien Luce and antimilitarist paintings by the neo-impressionist outsider, 'Le douanier' Rousseau. Far from picturing the patriotic honor of becoming a soldier and the victories of war, as did Edouard Detaille, Rousseau did the opposite. In the heat of military slaughter of families at Fourmies, Rousseau revealed how conscription would transform French citizens into le corps militaire to fight not just against their arch-enemy with machine-like precision but against their very own people.

  20. A carbon isotope budget for an anoxic marine sediment

    International Nuclear Information System (INIS)

    Boehme, S.E.; Blair, N.E.

    1991-01-01

    A carbon isotope budget has been determined for the coastal marine site, Cape Lookout Bight, NC. Isotope measurements of methane and σCO 2 fluxing out and buried in these sediments were applied to previously measured flux data (Martens et al., in press) to predict the isotopic composition of the incoming metabolizable organic matter. Methane leaves the sediment predominantly via ebullition with an isotopic composition of -60 per mil. Less than 2% of the methane produced is buried with an average diffusional flux value of -17 per mil and a burial value of +11 per mil. The isotope budget predicts a metabolizable organic carbon isotope signature of -19.3 per mil which is in excellent agreement with the measured total organic carbon value of -19.2 ± 0.3 per mil implying that the dominant remineralization processes have been identified

  1. Genome-wide Ancestry and Demographic History of African-Descendant Maroon Communities from French Guiana and Suriname.

    Science.gov (United States)

    Fortes-Lima, Cesar; Gessain, Antoine; Ruiz-Linares, Andres; Bortolini, Maria-Cátira; Migot-Nabias, Florence; Bellis, Gil; Moreno-Mayar, J Víctor; Restrepo, Berta Nelly; Rojas, Winston; Avendaño-Tamayo, Efren; Bedoya, Gabriel; Orlando, Ludovic; Salas, Antonio; Helgason, Agnar; Gilbert, M Thomas P; Sikora, Martin; Schroeder, Hannes; Dugoujon, Jean-Michel

    2017-11-02

    The transatlantic slave trade was the largest forced migration in world history. However, the origins of the enslaved Africans and their admixture dynamics remain unclear. To investigate the demographic history of African-descendant Marron populations, we generated genome-wide data (4.3 million markers) from 107 individuals from three African-descendant populations in South America, as well as 124 individuals from six west African populations. Throughout the Americas, thousands of enslaved Africans managed to escape captivity and establish lasting communities, such as the Noir Marron. We find that this population has the highest proportion of African ancestry (∼98%) of any African-descendant population analyzed to date, presumably because of centuries of genetic isolation. By contrast, African-descendant populations in Brazil and Colombia harbor substantially more European and Native American ancestry as a result of their complex admixture histories. Using ancestry tract-length analysis, we detect different dates for the European admixture events in the African-Colombian (1749 CE; confidence interval [CI]: 1737-1764) and African-Brazilian (1796 CE; CI: 1789-1804) populations in our dataset, consistent with the historically attested earlier influx of Africans into Colombia. Furthermore, we find evidence for sex-specific admixture patterns, resulting from predominantly European paternal gene flow. Finally, we detect strong genetic links between the African-descendant populations and specific source populations in Africa on the basis of haplotype sharing patterns. Although the Noir Marron and African-Colombians show stronger affinities with African populations from the Bight of Benin and the Gold Coast, the African-Brazilian population from Rio de Janeiro has greater genetic affinity with Bantu-speaking populations from the Bight of Biafra and west central Africa. Copyright © 2017 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  2. Impact of climate change on freshwater resources in a heterogeneous coastal aquifer of Bremerhaven, Germany: A three-dimensional modeling study.

    Science.gov (United States)

    Yang, Jie; Graf, Thomas; Ptak, Thomas

    2015-01-01

    Climate change is expected to induce sea level rise in the German Bight, which is part of the North Sea, Germany. Climate change may also modify river discharge of the river Weser flowing into the German Bight, which will alter both pressure and salinity distributions in the river Weser estuary. To study the long-term interaction between sea level rise, discharge variations, a storm surge and coastal aquifer flow dynamics, a 3D seawater intrusion model was designed using the fully coupled surface-subsurface numerical model HydroGeoSphere. The model simulates the coastal aquifer as an integral system considering complexities such as variable-density flow, variably saturated flow, irregular boundary conditions, irregular land surface and anthropogenic structures (e.g., dyke, drainage canals, water gates). The simulated steady-state groundwater flow of the year 2009 is calibrated using PEST. In addition, four climate change scenarios are simulated based on the calibrated model: (i) sea level rise of 1m, (ii) the salinity of the seaside boundary increases by 4 PSU (Practical Salinity Units), (iii) the salinity of the seaside boundary decreases by 12 PSU, and (iv) a storm surge with partial dyke failure. Under scenarios (i) and (iv), the salinized area expands several kilometers further inland during several years. Natural remediation can take up to 20 years. However, sudden short-term salinity changes in the river Weser estuary do not influence the salinized area in the coastal aquifer. The obtained results are useful for coastal engineering practices and drinking water resource management. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Gene expression and physiological changes of different populations of the long-lived bivalve Arctica islandica under low oxygen conditions.

    Directory of Open Access Journals (Sweden)

    Eva E R Philipp

    Full Text Available The bivalve Arctica islandica is extremely long lived (>400 years and can tolerate long periods of hypoxia and anoxia. European populations differ in maximum life spans (MLSP from 40 years in the Baltic to >400 years around Iceland. Characteristic behavior of A. islandica involves phases of metabolic rate depression (MRD during which the animals burry into the sediment for several days. During these phases the shell water oxygen concentrations reaches hypoxic to anoxic levels, which possibly support the long life span of some populations. We investigated gene regulation in A. islandica from a long-lived (MLSP 150 years German Bight population and the short-lived Baltic Sea population, experimentally exposed to different oxygen levels. A new A. islandica transcriptome enabled the identification of genes important during hypoxia/anoxia events and, more generally, gene mining for putative stress response and (anti- aging genes. Expression changes of a antioxidant defense: Catalase, Glutathione peroxidase, manganese and copper-zinc Superoxide dismutase; b oxygen sensing and general stress response: Hypoxia inducible factor alpha, Prolyl hydroxylase and Heat-shock protein 70; and c anaerobic capacity: Malate dehydrogenase and Octopine dehydrogenase, related transcripts were investigated. Exposed to low oxygen, German Bight individuals suppressed transcription of all investigated genes, whereas Baltic Sea bivalves enhanced gene transcription under anoxic incubation (0 kPa and, further, decreased these transcription levels again during 6 h of re-oxygenation. Hypoxic and anoxic exposure and subsequent re-oxygenation in Baltic Sea animals did not lead to increased protein oxidation or induction of apoptosis, emphasizing considerable hypoxia/re-oxygenation tolerance in this species. The data suggest that the energy saving effect of MRD may not be an attribute of Baltic Sea A. islandica chronically exposed to high environmental variability (oxygenation

  4. Anthropogenic and climatic influences on carbon fluxes from eastern North America to the Atlantic Ocean: A process-based modeling study

    Science.gov (United States)

    Tian, Hanqin; Yang, Qichun; Najjar, Raymond G.; Ren, Wei; Friedrichs, Marjorie A. M.; Hopkinson, Charles S.; Pan, Shufen

    2015-04-01

    The magnitude, spatiotemporal patterns, and controls of carbon flux from land to the ocean remain uncertain. Here we applied a process-based land model with explicit representation of carbon processes in streams and rivers to examine how changes in climate, land conversion, management practices, atmospheric CO2, and nitrogen deposition affected carbon fluxes from eastern North America to the Atlantic Ocean, specifically the Gulf of Maine (GOM), Middle Atlantic Bight (MAB), and South Atlantic Bight (SAB). Our simulation results indicate that the mean annual fluxes (±1 standard deviation) of dissolved organic carbon (DOC), particulate organic carbon (POC), and dissolved inorganic carbon (DIC) in the past three decades (1980-2008) were 2.37 ± 0.60, 1.06 ± 0.20, and 3.57 ± 0.72 Tg C yr-1, respectively. Carbon export demonstrated substantial spatial and temporal variability. For the region as a whole, the model simulates a significant decrease in riverine DIC fluxes from 1901 to 2008, whereas there were no significant trends in DOC or POC fluxes. In the SAB, however, there were significant declines in the fluxes of all three forms of carbon, and in the MAB subregion, DIC and POC fluxes declined significantly. The only significant trend in the GOM subregion was an increase in DIC flux. Climate variability was the primary cause of interannual variability in carbon export. Land conversion from cropland to forest was the primary factor contributing to decreases in all forms of C export, while nitrogen deposition and fertilizer use, as well as atmospheric CO2 increases, tended to increase DOC, POC, and DIC fluxes.

  5. The Carbon Budget of Coastal Waters of Eastern North America

    Science.gov (United States)

    Najjar, R.; Boyer, E. W.; Burdige, D.; Butman, D. E.; Cai, W. J.; Canuel, E. A.; Chen, R. F.; Friedrichs, M. A.; Griffith, P. C.; Herrmann, M.; Kemp, W. M.; Kroeger, K. D.; Mannino, A.; McCallister, S. L.; McGillis, W. R.; Mulholland, M. R.; Salisbury, J.; Signorini, S. R.; Tian, H.; Tzortziou, M.; Vlahos, P.; Wang, A. Z.; Zimmerman, R. C.; Pilskaln, C. H.

    2015-12-01

    Observations and the output of numerical and statistical models are synthesized to construct a carbon budget of the coastal waters of eastern North America. The domain extends from the head of tide to (roughly) the continental shelf break and from southern Florida to southern Nova Scotia. The domain area is 2% tidal wetlands, 19% estuarine open water, and 78% shelf water. Separate budgets are constructed for inorganic and organic carbon; for tidal wetlands, estuaries, and shelf waters; and for three main subregions: the Gulf of Maine, the Mid-Atlantic Bight, and the South Atlantic Bight. Net primary production for the study region is about 150 Tg C yr-1, with 12% occurring in tidal wetlands and 7% in estuaries. Though respiration and photosynthesis are nearly balanced in most systems and regions, tidal wetlands and shelf waters are each found to be net autotrophic whereas estuaries are net heterotrophic. The domain as a whole is a sink of 5 Tg C yr-1 of atmospheric CO2, with tidal wetlands and shelf waters taking up 10 Tg C yr-1 (split roughly equally) and estuaries releasing 5 Tg C yr-1 to the atmosphere. Carbon burial is about 3 Tg C yr-1, split roughly equally among tidal wetlands, estuaries, and shelf waters. Rivers supply 6-7 Tg C yr-1 to estuaries, about 2/3 of which is organic. Tidal wetlands supply an additional 4 Tg C yr-1 to estuaries, about half of which is organic. Carbon in organic and inorganic forms is exported from estuaries to shelf waters and from shelf waters to the open ocean. In summary, tidal wetlands and estuaries, though small in area, contribute substantially to the overall carbon budget of the region.

  6. Distribution of N2O in the Baltic Sea during transition from anoxic to oxic conditions

    Directory of Open Access Journals (Sweden)

    S. Walter

    2006-01-01

    Full Text Available In January 2003, a major inflow of cold and oxygen-rich North Sea Water terminated an ongoing stagnation period in parts of the central Baltic Sea. In order to investigate the role of North Sea Water inflow in the production of nitrous oxide (N2O, we measured dissolved and atmospheric N2O at 26 stations in the southern and central Baltic Sea in October 2003. At the time of our cruise, water renewal had proceeded to the eastern Gotland Basin, whereas the western Gotland Basin was still unaffected by the inflow. The deep water renewal was detectable in the distributions of temperature, salinity, and oxygen concentrations as well as in the distribution of the N2O concentrations: Shallow stations in the Kiel Bight and Pomeranian Bight were well-ventilated with uniform N2O concentrations near equilibrium throughout the water column. In contrast, stations in the deep basins, such as the Bornholm and the Gotland Deep, showed a clear stratification with deep water affected by North Sea Water. Inflowing North Sea Water led to changed environmental conditions, especially enhanced oxygen (O2 or declining hydrogen sulphide (H2S concentrations, thus, affecting the conditions for the production of N2O. Pattern of N2O profiles and correlations with parameters like oxygen and nitrate differed between the basins. Because of the positive correlation between ΔN2O and AOU in oxic waters the dominant production pathway seems to be nitrification rather than denitrification. Advection of N2O by North Sea Water was found to be of minor importance. A rough budget revealed a significant surplus of in situ produced N2O after the inflow. However, due to the permanent halocline, it can be assumed that the N2O produced does not reach the atmosphere. Hydrographic aspects therefore are decisive factors determining the final release of N2O produced to the atmosphere.

  7. Final Technical Report: DOE-Biological Ocean Margins Program. Microbial Ecology of Denitrifying Bacteria in the Coastal Ocean.

    Energy Technology Data Exchange (ETDEWEB)

    Lee Kerkhof

    2013-01-01

    The focus of our research was to provide a comprehensive study of the bacterioplankton populations off the coast of New Jersey near the Rutgers University marine field station using terminal restriction fragment polymorphism analysis (TRFLP) coupled to 16S rRNA genes for large data set studies. Our three revised objectives to this study became: (1) to describe bacterioplankton population dynamics in the Mid Atlantic Bight using TRFLP analysis of 16S rRNA genes. (2) to determine whether spatial and temporal factors are driving bacterioplankton community dynamics in the MAB using monthly samping along our transect line over a 2-year period. (3) to identify dominant members of a coastal bacterioplankton population by clonal library analysis of 16S rDNA genes and sequencing of PCR product corresponding to specific TRFLP peaks in the data set. Although open ocean time-series sites have been areas of microbial research for years, relatively little was known about the population dynamics of bacterioplankton communities in the coastal ocean on kilometer spatial and seasonal temporal scales. To gain a better understanding of microbial community variability, monthly samples of bacterial biomass were collected in 1995-1996 along a 34-km transect near the Long-Term Ecosystem Observatory (LEO-15) off the New Jersey coast. Surface and bottom sampling was performed at seven stations along a transect line with depths ranging from 1 to 35m (n=178). The data revealed distinct temporal patterns among the bacterioplankton communities in the Mid-Atlantic Bight rather than grouping by sample location or depth (figure 2-next page). Principal components analysis models supported the temporal patterns. In addition, partial least squares regression modeling could not discern a significant correlation from traditional oceanographic physical and phytoplankton nutrient parameters on overall bacterial community variability patterns at LEO-15. These results suggest factors not traditionally

  8. Seasonal variation of assemblage and feeding guild structure of fish species in a boreal tidal basin

    Science.gov (United States)

    Kellnreitner, Florian; Pockberger, Moritz; Asmus, Harald

    2012-08-01

    Species composition, abundance, feeding relationships and guild structure of the fish assemblage in the Sylt-Rømø bight, a tidal basin in the northern Wadden Sea, were investigated to show seasonal differences and the importance of functional groups in this area. The tidal flats and in shallow subtidal areas were sampled using a beach seine and a bottom trawl net was used for deeper subtidal areas and tidal gullies. Species richness of fish was highest in summer where 26 species were caught, while the lowest richness was recorded in winter (17 species). Clear differences in species richness and abundance were found between shallow areas and deeper parts of the bight. Clupea harengus and Ammodytes tobianus were the most abundant species in deeper areas, while Pomatoschistus microps and Pomatoschistus minutus dominated shallower waters. Gut contents of 27 fish species were identified and the guild structure analyzed by UPGMA clustering of niche overlaps. Calanoid copepods (19.9%), Crangon crangon (18.2%) and mysid shrimps (8.4%) were the most abundant prey items of all fish species combined. Seven feeding guilds were present in the fall and winter, and eight and six in spring and summer, respectively. Fish feeding on calanoid copepods and C. crangon were present year round, whereas the occurrence of other guilds varied between seasons. Species composition of prey changed through seasons and, for some fish species, even the feeding mode itself varied with season. Most noticeable, 11 fish species changed guilds between seasons. We found a convergence in summer towards abundant prey items, whereas in winter diet overlap was lower. This is the first investigation of guild structure of almost all fish species present in a Wadden Sea area, and shows that consideration of seasonal differences is essential when determining feeding relationships of fish in temperate areas.

  9. Meteorological Aspects of the Eastern North American Pattern with Impacts on Long Island Sound Salinity

    Directory of Open Access Journals (Sweden)

    Justin A. Schulte

    2017-07-01

    Full Text Available The eastern North American sea level pressure dipole (ENA pattern is a recently identified teleconnection pattern that has been shown to influence mid-Atlantic United States (U.S streamflow variability. Because the pattern was only recently identified, its impacts on U.S. precipitation and estuaries on daily to seasonal timescales is unknown. Thus, this paper presents the first seasonal investigation of ENA relationships with global atmospheric fields, U.S. precipitation, and mid-Atlantic estuarine salinity. We show that the ENA pattern explains up to 25–36% of precipitation variability across Texas and the western U.S. We also show that, for the Northeast U.S, the ENA pattern explains up to 65% of precipitation variability, contrasting with previous work showing how well-known climate indices can only explain a modest amount of precipitation variability. The strongest ENA-precipitation relationships are in the spring and fall. The relationships between the ENA pattern and precipitation across remote regions reflect the upper-atmospheric Rossby wave pattern associated with the ENA pattern that varies seasonally. The El-Nino/Southern Oscillation (ENSO is related to the spring ENA pattern, indicating that extended outlooks of the ENA pattern may be possible. We also show that the ENA index is strongly correlated with salinity and vertical haline stratification across coastal portions of the mid-Atlantic Bight so that hypoxia forecasts based on the ENA index may be possible. Statistical connections between vertical salinity gradient and ENSO were identified at lags of up two years, further highlighting the potential for extended hypoxia outlooks. The strong connection between anomalies for precipitation and mid-Atlantic Bight salinity suggests that the ENA pattern may be useful at an interdisciplinary level for better understanding historical regional climate variability and future impacts of climate change on regional precipitation and the

  10. Spatially-Resolved Influence of Temperature and Salinity on Stock and Recruitment Variability of Commercially Important Fishes in the North Sea.

    Directory of Open Access Journals (Sweden)

    Anna Akimova

    Full Text Available Understanding of the processes affecting recruitment of commercially important fish species is one of the major challenges in fisheries science. Towards this aim, we investigated the relation between North Sea hydrography (temperature and salinity and fish stock variables (recruitment, spawning stock biomass and pre-recruitment survival index for 9 commercially important fishes using spatially-resolved cross-correlation analysis. We used high-resolution (0.2° × 0.2° hydrographic data fields matching the maximal temporal extent of the fish population assessments (1948-2013. Our approach allowed for the identification of regions in the North Sea where environmental variables seem to be more influential on the fish stocks, as well as the regions of a lesser or nil influence. Our results confirmed previously demonstrated negative correlations between temperature and recruitment of cod and plaice and identified regions of the strongest correlations (German Bight for plaice and north-western North Sea for cod. We also revealed a positive correlation between herring spawning stock biomass and temperature in the Orkney-Shetland area, as well as a negative correlation between sole pre-recruitment survival index and temperature in the German Bight. A strong positive correlation between sprat stock variables and salinity in the central North Sea was also found. To our knowledge the results concerning correlations between North Sea hydrography and stocks' dynamics of herring, sole and sprat are novel. The new information about spatial distribution of the correlation provides an additional help to identify mechanisms underlying these correlations. As an illustration of the utility of these results for fishery management, an example is provided that incorporates the identified environmental covariates in stock-recruitment models.

  11. Derivation of the Photosynthetically Available Radiation from METEOSAT data

    Energy Technology Data Exchange (ETDEWEB)

    Schiller, K. [GKSS-Forschungszentrum Geesthacht GmbH (Germany). Inst. fuer Hydrophysik

    2001-07-01

    Two different models, a Physical Model and a Neural Net, are used for the derivation of the photosynthetically available radiation (PAR) from METEOSAT data in the German Bight. Both models are constructed for the calculation of PAR in the German Bight in terms of an easily accessible time series of PAR fields; advantages and disadvantages of both models are discussed. A software package was generated in IDL for the realisation on the computer, its structure is motivated and physic background informations are given. With slight modifications all programs can be applied for the calculation of PAR for arbitary regions (but not over land). A zip file containing all programs and classes used, the technical html documentation and this report can be obtained from http://gfesunl.gkss.de/software/meteosat2par. (orig.) [German] Zur Ableitung der zur Photosynthese zur Verfuegung stehenden Strahlung (PAR) in der Deutschen Bucht aus METEOSAT-Daten werden zwei verschiedene Modelle, ein Physikalisches Modell und ein Neuranales Netz, benutzt. Beide Modelle sind darauf ausgelegt, PAR in der Deutschen Bucht in Form einer einfach zugaenglichen Zeitreihe von PAR-Feldern zu berechnen; Vor- und Nachteile beider Modelle werden diskutiert. Zur Realisierung auf dem Computer wurde ein Programmpaket in IDL erstellt, dessen Struktur motiviert wird und physikalische Hintergruende erlaeutert werden. Alle Programme sind so angelegt, dass sie sich durch geringfuegige Modifikationen eignen, PAR auch fuer andere Gebiete (aber nicht ueber Land) zu berechnen. Ein Zip-File aller benutzter Programme, Klassen, der technischen Html-Dokumentation und dieses Berichtes kann bei http://gfesunl.gkss.de/software/meteosat2par bezogen werden. (orig.)

  12. Characteristics of storms driving wave-induced seafloor mobility on the U.S. East Coast continental shelf

    Science.gov (United States)

    Dalyander, P. Soupy; Butman, Bradford

    2015-01-01

    This study investigates the relationship between spatial and temporal patterns of wave-driven sediment mobility events on the U.S. East Coast continental shelf and the characteristics of the storms responsible for them. Mobility events, defined as seafloor wave stress exceedance of the critical stress of 0.35 mm diameter sand (0.2160 Pa) for 12 or more hours, were identified from surface wave observations at National Data Buoy Center buoys in the Middle Atlantic Bight (MAB) and South Atlantic Bight (SAB) over the period of 1997-2007. In water depths ranging from 36-48 m, there were 4-9 mobility events/year of 1-2 days duration. Integrated wave stress during events (IWAVES) was used as a combined metric of wave-driven mobility intensity and duration. In the MAB, over 67% of IWAVES was caused by extratropical storms, while in the SAB, greater than 66% of IWAVES was caused by tropical storms. On average, mobility events were caused by waves generated by storms located 800+ km away. Far-field hurricanes generated swell 2-4 days before the waves caused mobility on the shelf. Throughout most of the SAB, mobility events were driven by storms to the south, east, and west. In the MAB and near Cape Hatteras, winds from more northerly storms and low-pressure extratropical systems in the mid-western U.S. also drove mobility events. Waves generated by storms off the SAB generated mobility events along the entire U.S. East Coast shelf north to Cape Cod, while Cape Hatteras shielded the SAB area from swell originating to the north offshore of the MAB.

  13. Transport and Fate of Nutrients Along the U.S. East Coast

    Science.gov (United States)

    Hofmann, E. E.; Narvaez, D.; Friedrichs, M. A. M.; Najjar, R.; Tian, H.; Hyde, K.; Mannino, A.; Signorini, S. R.; Wilkin, J.; St-Laurent, P.

    2017-12-01

    As part of a NASA-funded multi-investigator project, a land-estuarine-ocean biogeochemical modeling system was implemented and verified with remote sensing and in situ data to examine processes controlling fluxes on land, their coupling to riverine systems, the delivery of materials to estuaries and the coastal ocean, and marine ecosystem responses to these changing riverine inputs and changing climate forcing. This modeling system is being used to develop nutrient budgets for the U.S. east coast continental shelf and to examine seasonal and interannual variability in nutrient fluxes. An important aspect of these nutrient budgets is the transport and fate of nutrients released along the inner shelf. Results from a five-year simulation (2004 to 2008) that used tracer releases from the main rivers along the Middle Atlantic Bight (MAB) and South Atlantic Bight (SAB) provide insights into transport pathways that connect the inner and outer continental shelf. Tracers released along the inner MAB spread along the shelf with a general southward and offshore transport. Inner shelf inputs from the large estuarine systems are transported to the mid and outer MAB shelf. Tracers that reach the mid to outer shelf can be entrained in the Gulf Stream. Export from the MAB to the SAB occurs during periods of southerly winds. Transport processes along the SAB are similar, but Gulf Stream entrainment is a larger component of tracer transport. Superimposed on the MAB and SAB transport patterns is considerable seasonal and interannual variability. The results from these retrospective simulations improve understanding of the coupling at the land-water interface and shelf-wide transport patterns that advance the ability to predict the effects of localized human impacts and broader-scale climate-related impacts on the U.S. east coast continental shelf system.

  14. Great Earthquakes, Gigantic Landslides, and the Continuing Enigma of the April Fool's Tsunami of 1946

    Science.gov (United States)

    Fryer, G. J.; Tryon, M. D.

    2005-12-01

    Paleotsunami studies can extend the record of great earthquakes back into prehistory, but what if the historical record itself is ambiguous? There is growing controversy about whether great earthquakes really occur along the Shumagin and Unimak segments of the Alaska-Aleutian system. The last great tsunami there was April 1, 1946, initiated by an earthquake whose magnitude has variously been reported from 7.1 to 8.5. Okal et al (BSSA, 2003) surveyed the near-field runup and concluded there were two sources: a magnitude 8.5 earthquake, which generated a Pacific-wide tsunami but which produced near-field runups no more than 18 m, and an earthquake-triggered slump whose tsunami reached 42 m at Scotch Cap Light near the western end of Unimak Island, but with runup rapidly decaying eastwards. An M8.5 earthquake, however, is incompatible with GPS strain measurements, which indicate that the maximum earthquake size off Unimak is M7.5. We have long contended that near- and far-field tsunamis were the result of a single earthquake-triggered debris avalanche down the Aleutian slope. In 2004 we were part of an expedition to map and explore the landslide, whose location seemed to be very tightly constrained by the known tsunami travel time to Scotch Cap Light. We found that neither our giant landslide nor Okal et al's smaller slump exist within 100 km of the presumed location. The explanation is obvious in retrospect: the tsunami was so large that it crossed the shallow Aleutian shelf as a bore travelling faster than the theoretical long-wave speed (which we had used to fix the location). Any landslide could only have occurred in an unsurveyed area farther east, off Unimak Bight, the central coast of Unimak Island. That location, however, conflicts with Okal et al's measurements of smaller runup along the Bight. We are now convinced that Okal et al confused the 1946 debris line with the lower line left by the 1957 tsunami. They were apparently unaware that the 1946 tsunami

  15. Comparison of aliphatic hydrocarbons, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, polybrominated diphenylethers, and organochlorine pesticides in Pacific sanddab (Citharichthys sordidus) from offshore oil platforms and natural reefs along the California coast

    Science.gov (United States)

    Gale, Robert W.; Tanner, Michael J.; Love, Milton S.; Nishimoto, Mary M.; Schroeder, Donna M.

    2013-01-01

    Recently, the relative exposure of Pacific sanddab (Citharichthys sordidus) to polycyclic aromatic hydrocarbons (PAHs) at oil-production platforms was reported, indicating negligible exposure to PAHs and no discernible differences between exposures at platforms and nearby natural areas sites. In this report, the potential for chronic PAH exposure in fish is reported, by measurement of recalcitrant, higher molecular weight PAHs in tissues of fish previously investigated for PAH metabolites in bile. A total of 34 PAHs (20 PAHs, 11 alkylated PAHs, and 3 polycyclic aromatic thiophenes) were targeted. In addition, legacy contaminants—polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs),—and current contaminants, polybrominated diphenylethers (PBDEs) linked to endocrine disruption, were measured by gas chromatography with electron-capture or mass spectrometric detection, to form a more complete picture of the contaminant-related status of fishes at oil production platforms in the Southern California Bight. No hydrocarbon profiles or unresolved complex hydrocarbon background were found in fish from platforms and from natural areas, and concentrations of aliphatics were low less than 100 nanograms per gram (ng/g) per component]. Total-PAH concentrations in fish ranged from 15 to 37 ng/g at natural areas and from 8.7 to 22 ng/g at platforms. Profiles of PAHs were similar at all natural and platform sites, consisting mainly of naphthalene and methylnaphthalenes, phenanthrene, fluoranthene, and pyrene. Total-PCB concentrations (excluding non-ortho-chloro-substituted congeners) in fish were low, ranging from 7 to 22 ng/g at natural areas and from 10 to 35 ng/g at platforms. About 50 percent of the total-PCBs at all sites consisted of 11 congeners: 153 > 138/163/164 > 110 > 118 > 15 > 99 > 187 > 149 > 180. Most OCPs, except dichlorodiphenyltrichloroethane (DDT)-related compounds, were not detectable or were at concentrations of less than 1 ng/g in fish. p

  16. Epifauna dynamics at an offshore foundation--implications of future wind power farming in the North Sea.

    Science.gov (United States)

    Krone, Roland; Gutow, Lars; Joschko, Tanja J; Schröder, Alexander

    2013-04-01

    In the light of the introduction of thousands of large offshore wind power foundations into the North Sea within the next decades, this manuscript focuses on the biofouling processes and likely reef effects. The study explores the macrozoobenthos (biofouling) colonization at an offshore platform which is comparable to offshore wind turbine foundations. A total of 183 single samples were taken and the parameters water depth and time were considered comparing biofouling masses and communities. The blue mussel Mytilus edulis, Anthozoa and the Amphipoda Jassa spp. were the dominant species. The community from the 1 m zone and those from the 5 and 20-28 m zones can clearly be differentiated. The 10 m zone community represents the transition between the M. edulis dominated 1 m and 5 m zones and the Anthozoa dominated 20-28 m zone. In the future offshore wind farms, thousands of wind turbine foundations will provide habitat for a hard bottom fauna which is otherwise restricted to the sparse rocky habitats scattered within extensive sedimentary soft bottoms of the German Bight. However, offshore wind power foundations cannot be considered natural rock equivalents as they selectively increase certain natural hard bottom species. The surface of the construction (1280 m²) was covered by an average of 4300 kg biomass. This foundation concentrates on its footprint area (1024 m²) 35 times more macrozoobenthos biomass than the same area of soft bottom in the German exclusive economic zone (0.12 kg m(-2)), functioning as a biomass hotspot. Concerning the temporal biomass variation, we assume that at least 2700 kg biomass was exported on a yearly basis. 345 × 10(4) single mussel shells of different sizes were produced during the study period. It is anticipated that the M. edulis abundance will increase in the North Sea due to the expansion of the offshore wind farm development. This will result in the enhanced production of secondary hard substrate (mussel shells

  17. Benthic community structures in the North Sea

    Science.gov (United States)

    Heip, C.; Craeymeersch, J. A.

    1995-03-01

    Coherent assemblages of marine benthic species have been recognized from the early twentieth century, and the classical papers of Petersen (1914, 1918) were based on studies of limited areas in the North Sea. In 1986, a synoptic survey of the North Sea north to 57°N was undertaken by a group of ten laboratories from seven North Sea countries. The results of this survey have recently been published (Heip et al., 1992a, b; Künitzer et al., 1992; Huys et al., 1992), and some of the results are summarized in this paper. The analysis of the macrofauna is based on slightly more than 700 taxa. In general, the North Sea macrofauna consists of northern species extending south to the northern margins of the Dogger Bank, and southern species extending north to the 100 m depth line. The central North Sea is an area of overlap of southern and northern species, especially around the 70 m depth contour. Consistent groupings of species are recognized that were summarized in seven faunal groupings. Macrofaunal body weight, density and diversity increase linearly towards the north. Macrofaunal biomass for the whole area averages 7 g adwt. m-2 and decreases from south to north. Distribution patterns and trends within the meiofauna were very different. Nematodes, which are the dominant taxon overall, are least abundant in the sandy sediments of the Southern Bight, then increase to a maximum around 53° 30' N and slowly decrease again towards the north. Copepod density and diversity are highest in the Southern Bight, due to the presence of many interstitial species. A large number of species new to science were recorded by the North Sea Benthos Survey and about 1500 species are expected to occur. Copepods show very distinct assemblages according to water depth and sediment type. The contrasting patterns in latitudinal gradients of body weight and number of species of macro- and meiofauna can be only partially explained. Latitude and sediment characteristics, such as grain size and

  18. Inner-shelf ocean dynamics and seafloor morphologic changes during Hurricane Sandy

    Science.gov (United States)

    Warner, John C.; Schwab, William C.; List, Jeffrey H.; Safak, Ilgar; Liste, Maria; Baldwin, Wayne

    2017-04-01

    Hurricane Sandy was one of the most destructive hurricanes in US history, making landfall on the New Jersey coast on October 30, 2012. Storm impacts included several barrier island breaches, massive coastal erosion, and flooding. While changes to the subaerial landscape are relatively easily observed, storm-induced changes to the adjacent shoreface and inner continental shelf are more difficult to evaluate. These regions provide a framework for the coastal zone, are important for navigation, aggregate resources, marine ecosystems, and coastal evolution. Here we provide unprecedented perspective regarding regional inner continental shelf sediment dynamics based on both observations and numerical modeling over time scales associated with these types of large storm events. Oceanographic conditions and seafloor morphologic changes are evaluated using both a coupled atmospheric-ocean-wave-sediment numerical modeling system that covered spatial scales ranging from the entire US east coast (1000 s of km) to local domains (10 s of km). Additionally, the modeled response for the region offshore of Fire Island, NY was compared to observational analysis from a series of geologic surveys from that location. The geologic investigations conducted in 2011 and 2014 revealed lateral movement of sedimentary structures of distances up to 450 m and in water depths up to 30 m, and vertical changes in sediment thickness greater than 1 m in some locations. The modeling investigations utilize a system with grid refinement designed to simulate oceanographic conditions with progressively increasing resolutions for the entire US East Coast (5-km grid), the New York Bight (700-m grid), and offshore of Fire Island, NY (100-m grid), allowing larger scale dynamics to drive smaller scale coastal changes. Model results in the New York Bight identify maximum storm surge of up to 3 m, surface currents on the order of 2 ms-1 along the New Jersey coast, waves up to 8 m in height, and bottom stresses

  19. Inner-shelf ocean dynamics and seafloor morphologic changes during Hurricane Sandy

    Science.gov (United States)

    Warner, John C.; Schwab, William C.; List, Jeffrey; Safak, Ilgar; Liste, Maria; Baldwin, Wayne E.

    2017-01-01

    Hurricane Sandy was one of the most destructive hurricanes in US history, making landfall on the New Jersey coast on Oct 30, 2012. Storm impacts included several barrier island breaches, massive coastal erosion, and flooding. While changes to the subaerial landscape are relatively easily observed, storm-induced changes to the adjacent shoreface and inner continental shelf are more difficult to evaluate. These regions provide a framework for the coastal zone, are important for navigation, aggregate resources, marine ecosystems, and coastal evolution. Here we provide unprecedented perspective regarding regional inner continental shelf sediment dynamics based on both observations and numerical modeling over time scales associated with these types of large storm events. Oceanographic conditions and seafloor morphologic changes are evaluated using both a coupled atmospheric-ocean-wave-sediment numerical modeling system and observation analysis from a series of geologic surveys and oceanographic instrument deployments focused on a region offshore of Fire Island, NY. The geologic investigations conducted in 2011 and 2014 revealed lateral movement of sedimentary structures of distances up to 450 m and in water depths up to 30 m, and vertical changes in sediment thickness greater than 1 m in some locations. The modeling investigations utilize a system with grid refinement designed to simulate oceanographic conditions with progressively increasing resolutions for the entire US East Coast (5-km grid), the New York Bight (700-m grid), and offshore of Fire Island, NY (100-m grid), allowing larger scale dynamics to drive smaller scale coastal changes. Model results in the New York Bight identify maximum storm surge of up to 3 m, surface currents on the order of 2 ms-1 along the New Jersey coast, waves up to 8 m in height, and bottom stresses exceeding 10 Pa. Flow down the Hudson Shelf Valley is shown to result in convergent sediment transport and deposition along its axis

  20. Sediment movement along the U.S. east coast continental shelf—II. Modelling suspended sediment concentration and transport rate during storms

    Science.gov (United States)

    Lyne, Vincent D.; Butman, Bradford; Grant, William D.

    1990-05-01

    Long-term near-bottom wave and current observations and a one-dimensional sediment transport model are used to calculate the concentration and transport of sediment during winter storms at 60-80 m water depth along the southern flank of Georges Bank and in the Mid-Atlantic Bight. Calculations are presented for five stations, separated by more than 600 km alongshelf, that have different bottom sediment texture, bedforms and current conditions. A modified version of the sediment transport model presented by GRANT and GLENN (1983, Technical Report to the American Gas Association), GLENN (1983, D.Sc. Thesis, M.I.T.), and GLENN and GRANT (1987, Journal of Geophysical Research, 92, 8244-8264) is used to examine the influence of wave-current interaction, sediment stratification, and limitations on the erodibility of the bottom sediments on the concentration of sediment in the water column and on transport. Predicted suspended sediment concentrations are higher than observed, based on beam transmissometer measurements, unless an erosion limit of order a few millimeters for sediments finer than 94 μm is imposed. The agreement between predicted and measured beam attenuation is better at stations that have significant amounts of silt plus clay in the surficial sediments than for stations with sandy sediments. Sediment concentrations during storms estimated by MOODYet al. (1987, Continental Shelf Research, 7, 609-628) are within 50% of the model predictions. Sediment transport rates for sediments 94 μm and finer are determined largely by the concentrations in the surficial sediment and the erosion depth limit. Large alongshelf transports in the direction of storm-driven currents are inferred for stations in the Mid-Atlantic Bight. During a 115-day period in winter 1979-1980, the net transport of sediment along the shelf was westward; benthic storms (defined as periods when the bottom wave stress exceeded the current stress by 2 dyn cm -2) occurred between 23 and 73% of the

  1. Marine habitat mapping, classification and monitoring in the coastal North Sea: Scientific vs. stakeholder interests

    Science.gov (United States)

    Hass, H. Christian; Mielck, Finn; Papenmeier, Svenja; Fiorentino, Dario

    2016-04-01

    Producing detailed maps of the seafloor that include both, water depth and simple textural characteristics has always been a challenge to scientists. In this context, marine habitat maps are an essential tool to comprehend the complexity, the spatial distribution and the ecological status of different seafloor types. The increasing need for more detail demands additional information on the texture of the sediment, bedforms and information on benthic sessile life. For long time, taking samples and videos/photographs followed by interpolation over larger distances was the only feasible way to gain information about sedimentary features such as grain-size distribution and bedforms. While ground truthing is still necessary, swath systems such as multibeam echo sounders (MBES) and sidescan sonars (SSS), as well as single beam acoustic ground discrimination systems (AGDS) became available to map the seafloor area-wide (MBES, SSS), fast and in great detail. Where area-wide measurements are impossible or unavailable point measurements are interpolated, classified and modeled. To keep pace with environmental change in the highly dynamic coastal areas of the North Sea (here: German Bight) monitoring that utilizes all of the mentioned techniques is a necessity. Since monitoring of larger areas is quite expensive, concepts for monitoring strategies were developed in scientific projects such as "WIMO" ("Scientific monitoring concepts for the German Bight, SE North Sea"). While instrumentation becomes better and better and interdisciplinary methods are being developed, the gap between basic scientific interests and stakeholder needs often seem to move in opposite directions. There are two main tendencies: the need to better understand nature systems (for theoretical purposes) and the one to simplify nature (for applied purposes). Science trends to resolve the most detail in highest precision employing soft gradients and/or fuzzy borders instead of crisp demarcations and

  2. By the Light of the Moon: North Pacific Dolphins Optimize Foraging with the Lunar Cycle

    Science.gov (United States)

    Simonis, Anne Elizabeth

    The influence of the lunar cycle on dolphin foraging behavior was investigated in the productive, southern California Current Ecosystem and the oligotrophic Hawaiian Archipelago. Passive acoustic recordings from 2009 to 2015 were analyzed to document the presence of echolocation from four dolphin species that demonstrate distinct foraging preferences and diving abilities. Visual observations of dolphins, cloud coverage, commercial landings of market squid (Doryteuthis opalescens) and acoustic backscatter of fish were also considered in the Southern California Bight. The temporal variability of echolocation is described from daily to annual timescales, with emphasis on the lunar cycle as an established behavioral driver for potential dolphin prey. For dolphins that foraged at night, the presence of echolocation was reduced during nights of the full moon and during times of night that the moon was present in the night sky. In the Southern California Bight, echolocation activity was reduced for both shallow- diving common dolphins (Delphinus delphis) and deeper-diving Risso's dolphins (Grampus griseus) during times of increased illumination. Seasonal differences in acoustic behavior for both species suggest a geographic shift in dolphin populations, shoaling scattering layers or prey switching behavior during warm months, whereby dolphins target prey that do not vertically migrate. In the Hawaiian Archipelago, deep-diving short-finned pilot whales (Globicephala macrorhynchus) and shallow-diving false killer whales (Pseudorca crassidens) also showed reduced echolocation behavior during periods of increased lunar illumination. In contrast to nocturnal foraging in the northwestern Hawaiian Islands, false killer whales in the main Hawaiian Islands mainly foraged during the day and the lunar cycle showed little influence on their nocturnal acoustic behavior. Different temporal patterns in false killer whale acoustic behavior between the main and northwestern Hawaiian

  3. On the predictability of high water level along the US East Coast: can the Florida Current measurement be an indicator for flooding caused by remote forcing?

    Science.gov (United States)

    Ezer, Tal; Atkinson, Larry P.

    2017-06-01

    Recent studies show that in addition to wind and air pressure effects, a significant portion of the variability of coastal sea level (CSL) along the US East Coast can be attributed to non-local factors such as variations in the Gulf Stream and the North Atlantic circulation; these variations can cause unpredictable coastal flooding. The Florida Current transport (FCT) measurement across the Florida Straits monitors those variations, and thus, the study evaluated the potential of using the FCT as an indicator for anomalously high water level along the coast. Hourly water level data from 12 tide gauge stations over 12 years are used to construct records of maximum daily water levels (MDWL) that are compared with the daily FCT data. An empirical mode decomposition (EMD) approach is used to divide the data into high-frequency modes (periods T anti-correlated with MDWL in high-frequency modes but positively correlated with MDWL in low-frequency modes. FCC on the other hand is always anti-correlated with MDWL for all frequency bands, and the high water signal lags behind FCC for almost all stations, thus providing a potential predictive skill (i.e., whenever a weakening trend is detected in the FCT, anomalously high water is expected along the coast over the next few days). The MDWL-FCT correlation in the high-frequency modes is maximum in the lower Mid-Atlantic Bight, suggesting influence from the meandering Gulf Stream after it separates from the coast. However, the correlation in low-frequency modes is maximum in the South Atlantic Bight, suggesting impact from variations in the wind pattern over subtropical regions. The middle-frequency and low-frequency modes of the FCT seem to provide the best predictor for medium to large flooding events; it is estimated that ˜10-25% of the sea level variability in those modes can be attributed to variations in the FCT. An example from Hurricane Joaquin (September-October, 2015) demonstrates how an offshore storm that never made

  4. 150 years of ecosystem evolution in the North Sea - from pristine conditions to acidification

    Science.gov (United States)

    Pätsch, Johannes; Lorkowski, Ina; Kühn, Wilfried; Moll, Andreas; Serna, Alexandra

    2010-05-01

    The 3-d coupled physical-biogeochemical model ECOHAM was applied to the Northwest European Shelf (47° 41‘ - 63° 53' N, 15° 5' W - 13° 55' E) for the years 1860, 1960 and continuously for the time interval 1970 - 2006. From stable nitrogen isotope analysis in sediment cores of the German Bight in the southeastern part of the North Sea (inner shelf) we found the period before 1860 unaffected by anthropogenic river inputs of nitrogen. After this period the delta15N-ratios significantly increased from ~6 per mil to more than 8 per mil in recent sediments indicating eutrophication by anthropogenic nitrate mainly from intensive agriculture fertilization. We deduced from the successful simulation of delta15N patterns in recent sediments that during pristine conditions nitrogen loads of the main continental rivers were about 10% of the modern input while the deposition of inorganic atmospheric nitrogen was 28% of the recent atmospheric flux. The 1960-sediment exhibited similar delta15N-values as the recent sediment which allows the conclusion that eutrophication in the German Bight predates the 1960 period of rapidly increasing river loads. By comparing model results with observational data in the North Sea we analyzed the variability of simulated carbon fluxes (1970-2006) constituting the so called "shelf pump" which transports atmospheric CO2 via biological fixation, vertical export and advection into the adjacent North Atlantic. Even though the highly variable North Atlantic water-inflow which correlated with the North Atlantic Oscillation Index (NAOI) supplied the northern North Sea with strongly varying nutrient inputs, the interannual variability of the strength of the shelf pump was mainly governed by the variability of the southern basin's biological productivity. The net ecosystem production (NEP) in the southern North Sea varies around zero inducing CO2 exchange with the atmosphere which is near equilibrium. In the northern North Sea the strong positive

  5. Reply to: Terry, J. and Goff, J. comment on “Late Cenozoic sea level and the rise of modern rimmed atolls” by Toomey et al. (2016), Palaeogeography, Palaeoclimatology, Palaeoecology 4 51: 73–83.

    Science.gov (United States)

    Toomey, Michael; Ashton, Andrew; Raymo, Maureen E.; Perron, J. Taylor

    2017-01-01

    We appreciate Terry and Goff's thoughtful comment in response to our proposed atoll development model. Flank collapse of reef-built slopes likely does affect plan-form atoll morphology in some locations and potentially poses a tsunami hazard to low-lying Pacific islands (Terry and Goff, 2013). However, given the often rapid rates of lagoon infill (> 1 mm/yr; Montaggioni, 2005), such failure events would likely need to be frequent and widespread in order to leave a morphologic imprint on modern western Pacific atoll lagoon depths. Few atoll flank collapse features have been dated but many of the arcuate bight-like structures (ABLS) identified could be inherited from scars incised into the initial volcanic edifice (e.g. Terry and Goff, 2013 and refs. therein) — submarine mass wasting has been extensively documented on young hotspot islands (e.g. Hawaiian Islands: Moore et al., 1989; Reunion: Oehler et al., 2008). Atolls in the Marshall Islands, where our main study site Enewetak Atoll is located, are likely ~ 50–100 million years old (Larson et al., 1995) and dating of adjacent deep-water turbidite aprons in the Nauru Basin (DSDP Site 462; Schlanger and Silva, 1986) suggests that large atoll flank collapse events have been relatively infrequent there since the mid-Miocene (wasting events, will be essential for exploring the plan-form and 3D shapes of atolls. To our knowledge, no quantitative model of long-term atoll development has explicitly linked lagoon restriction/sedimentation to episodic flank collapse events (e.g. Montaggioni et al., 2015; Paterson et al., 2006; Quinn, 1991; Warrlich et al., 2002). Testing Terry and Goff's proposed conceptual model for how rim failure processes affect atoll morphology in a numerical context will require deep drilling along arcuate bight-like structures, as well as adjacent, unaffected, rim and lagoon areas, in order quantify how often failures occur and how quickly the rim/lagoon is rebuilt afterwards. The model we present

  6. Satellite-Derived Distributions, Inventories and Fluxes of Dissolved and Particulate Organic Matter Along the Northeastern U.S. Continental Margin

    Science.gov (United States)

    Mannino, A.; Hooker, S. B.; Hyde, K.; Novak, M. G.; Pan, X.; Friedrichs, M.; Cahill, B.; Wilkin, J.

    2011-01-01

    Estuaries and the coastal ocean experience a high degree of variability in the composition and concentration of particulate and dissolved organic matter (DOM) as a consequence of riverine and estuarine fluxes of terrigenous DOM, sediments, detritus and nutrients into coastal waters and associated phytoplankton blooms. Our approach integrates biogeochemical measurements, optical properties and remote sensing to examine the distributions and inventories of organic carbon in the U.S. Middle Atlantic Bight and Gulf of Maine. Algorithms developed to retrieve colored DOM (CDOM), Dissolved (DOC) and Particulate Organic Carbon (POC) from NASA's MODIS-Aqua and SeaWiFS satellite sensors are applied to quantify the distributions and inventories of DOC and POC. Horizontal fluxes of DOC and POC from the continental margin to the open ocean are estimated from SeaWiFS and MODIS-Aqua distributions of DOC and POC and horizontal divergence fluxes obtained from the Northeastern North Atlantic ROMS model. SeaWiFS and MODIS imagery reveal the importance of estuarine outflow to the export of CDOM and DOC to the coastal ocean and a net community production of DOC on the shelf.

  7. Apparent Minimum Free Energy Requirements for Methanogenic Archaea and Sulfate-Reducing Bacteria in an Anoxic Marine Sediment

    Science.gov (United States)

    Hoehler, Tori M.; Alperin, Marc J.; Albert, Daniel B.; Martens, Christopher S.; DeVincenzi, Don (Technical Monitor)

    2000-01-01

    Among the most fundamental constraints governing the distribution of microorganisms in the environment is the availability of chemical energy at biologically useful levels. To assess the minimum free energy yield that can support microbial metabolism in situ, we examined the thermodynamics of H2-consuming processes in anoxic sediments from Cape Lookout Bight, NC, USA. Depth distributions of H2 partial pressure, along with a suite of relevant concentration data, were determined in sediment cores collected in November (at 14.5 C) and August (at 27 C) and used to calculate free energy yields for methanogenesis and sulfate reduction. At both times of year, and for both processes, free energy yields gradually decreased (became less negative) with depth before reaching an apparent asymptote. Sulfate reducing bacteria exhibited an asymptote of -19.1 +/- 1.7 kj(mol SO4(2-)(sup -1) while methanogenic archaea were apparently supported by energy yields as small as -10.6 +/- 0.7 kj(mol CH4)(sup -1).

  8. Cetacean mother-calf behavior observed from a small aircraft off Southern California. Animal Behavior and Cognition

    Directory of Open Access Journals (Sweden)

    Mari A. Smultea

    2017-02-01

    Full Text Available During early developmental stages, cetacean calves are dependent on their mothers for survival. Protection of young whales engaged in behaviors that are biologically important is critical for population recovery, so that appropriate management actions can be taken to minimize human disturbance. However, the occurrence and frequency of whale nursing and calves back-riding their mothers (both considered important to calf survival have rarely been observed nor adequately quantified or defined. Therefore, it may not always be clear when disruption is occurring. We used extended behavioral observations, still photography, and video camera footage obtained during aircraft surveys in the Southern California Bight in 2008 – 2013 to characterize cetacean mother-calf interactions. Based on observations of four mother/calf pairs (two gray whale, Eschrichtius robustus, one fin whale, Balaenoptera physalus, and one blue whale, B. musculus and one killer whale presumed mother/yearling pair (Orcinus orca, we describe bouts of nursing and calves riding on the backs of their presumed mothers, including activity duration, frequency, and relative body positioning. We conclude with specific definitions useful to wildlife conservation agencies authorizing and establishing restrictions to certain human activities when they might constitute behavioral disruptions.

  9. Simulations and observation of nonlinear internal waves on the continental shelf: Korteweg–de Vries and extended Korteweg–de Vries solutions

    Directory of Open Access Journals (Sweden)

    K. O'Driscoll

    2017-09-01

    Full Text Available Numerical solutions of the Korteweg–de Vries (KdV and extended Korteweg–de Vries (eKdV equations are used to model the transformation of a sinusoidal internal tide as it propagates across the continental shelf. The ocean is idealized as being a two-layer fluid, justified by the fact that most of the oceanic internal wave signal is contained in the gravest mode. The model accounts for nonlinear and dispersive effects but neglects friction, rotation and mean shear. The KdV model is run for a number of idealized stratifications and unique realistic topographies to study the role of the nonlinear and dispersive effects. In all model solutions the internal tide steepens forming a sharp front from which a packet of nonlinear solitary-like waves evolve. Comparisons between KdV and eKdV solutions are made. The model results for realistic topography and stratification are compared with observations made at moorings off Massachusetts in the Middle Atlantic Bight. Some features of the observations compare well with the model. The leading face of the internal tide steepens to form a shock-like front, while nonlinear high-frequency waves evolve shortly after the appearance of the jump. Although not rank ordered, the wave of maximum amplitude is always close to the jump. Some features of the observations are not found in the model. Nonlinear waves can be very widely spaced and persist over a tidal period.

  10. A Holocene progradation record from Okains Bay, Banks Peninsula, Canterbury, New Zealand

    International Nuclear Information System (INIS)

    Stephenson, W.; Shulmeister, J.

    1999-01-01

    Fifty-eight distinct ridges are preserved on the Holocene progradation plain in Okains Bay, Banks Peninsula, Canterbury. Of these, 48 represent beach berm and foredune complexes and the remaining 10 are transverse dune ridges. Periods of rapid coastal progradation are marked by multiple beach berm preservation, whereas intervening periods of lower sediment accumulation result in a stable coastline and transverse dune formation. Infilling of the bay began following sea-level stabilisation in the mid Holocene. The fill is dominantly fine sand, which is derived from sediment carried around Banks Peninsula in the Southland Current and washed into Okains Bay by wave action. Variations in the progradation rate are therefore proxy indicators of coastal erosion in the Canterbury Bight. We demonstrate that there is little progradational fill preserved between c. 6500 and 2000 yr BP. This implies significant changes in sediment delivery to the Southland Current within the last 2000 yr, which we attribute to increased coastal erosion in South Canterbury. We speculate that this increasing erosion resulted from increased wave energy regimes, which in turn may relate to increasing Southern Hemisphere seasonality following the precessional cycle. (author). 32 refs., 4 figs., 3 tabs

  11. Stochastic Ocean Predictions with Dynamically-Orthogonal Primitive Equations

    Science.gov (United States)

    Subramani, D. N.; Haley, P., Jr.; Lermusiaux, P. F. J.

    2017-12-01

    The coastal ocean is a prime example of multiscale nonlinear fluid dynamics. Ocean fields in such regions are complex and intermittent with unstationary heterogeneous statistics. Due to the limited measurements, there are multiple sources of uncertainties, including the initial conditions, boundary conditions, forcing, parameters, and even the model parameterizations and equations themselves. For efficient and rigorous quantification and prediction of these uncertainities, the stochastic Dynamically Orthogonal (DO) PDEs for a primitive equation ocean modeling system with a nonlinear free-surface are derived and numerical schemes for their space-time integration are obtained. Detailed numerical studies with idealized-to-realistic regional ocean dynamics are completed. These include consistency checks for the numerical schemes and comparisons with ensemble realizations. As an illustrative example, we simulate the 4-d multiscale uncertainty in the Middle Atlantic/New York Bight region during the months of Jan to Mar 2017. To provide intitial conditions for the uncertainty subspace, uncertainties in the region were objectively analyzed using historical data. The DO primitive equations were subsequently integrated in space and time. The probability distribution function (pdf) of the ocean fields is compared to in-situ, remote sensing, and opportunity data collected during the coincident POSYDON experiment. Results show that our probabilistic predictions had skill and are 3- to 4- orders of magnitude faster than classic ensemble schemes.

  12. Environmental impact assessment. Investigation of marine mammals in relation to the establishment of a marine wind farm on Horns Reef

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-02-15

    Elsamproject has decided to carry out an environmental impact assessment with the aim to investigate whether the establishment of a marine wind farm on Horns Reef may impact on breeding and non-breeding marine mammals, particularly harbour porpoise Phocoena phocoena and common seal Phoca vitulina. The marine mammals of the northern part of the German Bight can be characterised by a regular occurrence of harbour porpoise and common seal throughout the year, an irregular occurrence of grey seal Halichoerus grypus and white-beaked dolphin Lagenorhynchus albirostris and rare occurrences of white-sided dolphin Lagenorhynchus acutus, minke whale Balaenoptera acutorostrata, sperm whale Physeter macrocephalus, long-finned pilot whale Globicephala melas and killer whale Orcinus orca. The environment impact assessment therefore focuses on the evaluation of the possible effects on harbour porpoise and common seal. The investigation constitutes the first phase of a before-after-control-impact (BACI) analysis of the occurrence of harbour porpoise before, during and after the construction of the wind farm. (au)

  13. How phosphorus limitation can control climatic gas sources and sinks

    Science.gov (United States)

    Gypens, Nathalie; Borges, Alberto V.; Ghyoot, Caroline

    2017-04-01

    Since the 1950's, anthropogenic activities severely increased river nutrient loads in European coastal areas. Subsequent implementation of nutrient reduction policies have considerably reduced phosphorus (P) loads from mid-1980's, while nitrogen (N) loads were maintained, inducing a P limitation of phytoplankton growth in many eutrophied coastal areas such as the Southern Bight of the North Sea (SBNS). When dissolved inorganic phosphorous (DIP) is limiting, most phytoplankton organisms are able to indirectly acquire P from dissolved organic P (DOP). We investigate the impact of DOP use on the importance of phytoplankton production and atmospheric fluxes of CO2 and dimethylsulfide (DMS) in the SBNS from 1951 to 2007 using an extended version of the R-MIRO-BIOGAS model. This model includes a description of the ability of phytoplankton organisms to use DOP as a source of P. Results show that primary production can increase up to 70% due to DOP uptake in limiting DIP conditions. Consequently, simulated DMS emissions double while CO2 emissions to the atmosphere decrease, relative to the reference simulation without DOP uptake. At the end of the simulated period (late 2000's), the net direction of air-sea CO2 annual flux, changed from a source to a sink for atmospheric CO2 in response to use of DOP and increase of primary production.

  14. How phosphorus limitation can control climate-active gas sources and sinks

    Science.gov (United States)

    Gypens, Nathalie; Borges, Alberto V.; Ghyoot, Caroline

    2017-06-01

    Since the 1950's, anthropogenic activities have increased nutrient river loads to European coastal areas. Subsequent implementation of nutrient reduction policies have led to considerably reduction of phosphorus (P) loads from the mid-1980's, while nitrogen (N) loads were maintained, inducing a P limitation of phytoplankton growth in many eutrophied coastal areas such as the Southern Bight of the North Sea (SBNS). When dissolved inorganic phosphorus (DIP) is limiting, most phytoplankton organisms are able to indirectly acquire P from dissolved organic P (DOP). We investigate the impact of DOP use on phytoplankton production and atmospheric fluxes of CO2 and dimethylsulfide (DMS) in the SBNS from 1951 to 2007 using an extended version of the R-MIRO-BIOGAS model. This model includes a description of the ability of phytoplankton organisms to use DOP as a source of P. Results show that primary production can increase up to 30% due to DOP uptake under limiting DIP conditions. Consequently, simulated DMS emissions also increase proportionally while CO2 emissions to the atmosphere decrease, relative to the reference simulation without DOP uptake.

  15. Number One Reef: An overstepped segmented lagoon complex on the KwaZulu-Natal continental shelf

    Directory of Open Access Journals (Sweden)

    Godfrey Vella

    2012-07-01

    Full Text Available This study of the bathymetry of the mid-shelf of the Durban Bight, KwaZulu-Natal revealed a series of previously undocumented seafloor features. These features were mapped using a high-resolution multibeam bathymetric echosounder and a detailed map of the seafloor topography was produced. We recognised several features that closely resemble features of contemporary segmented lagoon and lake systems: semicircular seafloor depressions, arcuate ridges, cuspate spits and prograding submerged barriers. Based on the striking similarity in morphology to Kosi Bay – a segmented lagoon system from the sandy northern KwaZulu-Natal coastal plain – a similar evolutionary model is proposed. This model is of an incised valley formed following a sea level lowering to the Last Glacial Maximum at about 18 000 BP. Thereafter, continued transgressive infilling occurred to a point where an extensive lagoon and back-barrier system was established. At this point, sea levels remained static, causing the net segmentation of the system and the slow closure of the tidal basins or circular depressions. This type of seafloor topography is rarely preserved and is the result of fortuitous cementation after deposition and the later removal of sediment that would ordinarily bury such features.

  16. Blue whales respond to anthropogenic noise.

    Directory of Open Access Journals (Sweden)

    Mariana L Melcón

    Full Text Available Anthropogenic noise may significantly impact exposed marine mammals. This work studied the vocalization response of endangered blue whales to anthropogenic noise sources in the mid-frequency range using passive acoustic monitoring in the Southern California Bight. Blue whales were less likely to produce calls when mid-frequency active sonar was present. This reduction was more pronounced when the sonar source was closer to the animal, at higher sound levels. The animals were equally likely to stop calling at any time of day, showing no diel pattern in their sensitivity to sonar. Conversely, the likelihood of whales emitting calls increased when ship sounds were nearby. Whales did not show a differential response to ship noise as a function of the time of the day either. These results demonstrate that anthropogenic noise, even at frequencies well above the blue whales' sound production range, has a strong probability of eliciting changes in vocal behavior. The long-term implications of disruption in call production to blue whale foraging and other behaviors are currently not well understood.

  17. British battleships of world war one new revised edition

    CERN Document Server

    Burt, R A

    2012-01-01

    This superb reference book achieved the status of 'classic' soon after its first publication in 1986; it was soon out of print and is now one of the most sought-after naval reference books on the secondhand market.
It presents, in one superb volume, the complete technical history of British capital ship design and construction during the dreadnought era. One hundred years ago at Jutland, Dogger Bank, Heligoland Bight and the first battle for the Falklands, might squadrons of these great armoured ships fought their German counterparts for command of the seas. Beginning with Dreadnought, the book continues to the end of the First World War, and all of the fifty dreadnoughts, 'super-dreadnoughts' and battlecruisers that served the Royal Navy during this era are described and superbly illustrated with photographs and line drawings. 
Each class of ship is described in detail so that design origins, and technical and operational factors, are discussed alongside characteristics, with special emphasis on armament...

  18. Natural isotopic composition of nitrogen as a tracer of origin for suspended organic matter in the Scheldt estuary

    International Nuclear Information System (INIS)

    Mariotti, A.; Lancelot, C.; Billen, G.

    1984-01-01

    The natural isotopic composition of suspended particulate organic nitrogen was determined in the Southern Bight of the North Sea and in the Scheldt estuary. These data show that delta 15 N constitutes a convenient tracer of the origin of the suspended matter. In the winter, in the absence of intensive primary production, the suspended organic matter of the Scheldt estuary is a mixture of two components: a continental detrital component characterized by a low delta value of 1.5per mille and a marine component with a mean delta value of 8per mille. During the phytoplankton flowering period, lasting from early May to October, intensive primary production occurs throughout the estuary giving rise to a third source of organic matter. This material is characterized by high delta values reflecting the isotopic composition of ammonia, the nitrogenous nutrient assimilated by phytoplankton in the estuary. The nitrification process occuring in the mixing area of the Scheldt estuary leads to higher downstream delta values of ammonia (> 20per mille) which permits the distinction between estuarine from fresh-water phytoplankton. Simple isotopic budget calculations show that, both in the upstream part and in the downstream part, autochthonous phytoplanktonic material contributes a major part of the total suspended matter in the Scheldt estuary during summer. (author)

  19. Microbial degradation of dissolved proteins in seawater

    International Nuclear Information System (INIS)

    Hollibaugh, J.T.; Azam, F.

    1983-01-01

    An experimental protocol using radiolabeled proteins was developed to investigate the rates and mechanisms whereby dissolved proteins are degraded in natural marine plankton communities. The results of field observations and laboratory experiments indicate that proteins are degraded by a particle-bound, thermolabile system, presumably bacteria-associated enzymes, with an apparent half-saturation constant of ca. 25 μg bovine serum albumin (BSA) per liter. Gel permeation chromatography indicated that peptides of chain length intermediate between BSA and the final products of degradation (MW<700) do not accumulate in the medium. Competition experiments indicate that the system is relatively nonspecific. Turnover rates for the protein pool in samples collected in the Southern California Bight were of the same order of magnitude as the turnover rate of the L-leucine pool and were correlated with primary productivity, chlorophyll a concentrations, bacterial abundance and biomass, and L-leucine turnover rate. These data suggest that amino acids derived from proteins are utilized preferentially and do not completely mix with the amino acids in the bulk phase

  20. Linking Compositional and Functional Predictions to Decipher the Biogeochemical Significance in DFAA Turnover of Abundant Bacterioplankton Lineages in the North Sea

    Directory of Open Access Journals (Sweden)

    Bernd Wemheuer

    2017-11-01

    Full Text Available Deciphering the ecological traits of abundant marine bacteria is a major challenge in marine microbial ecology. In the current study, we linked compositional and functional predictions to elucidate such traits for abundant bacterioplankton lineages in the North Sea. For this purpose, we investigated entire and active bacterioplankton composition along a transect ranging from the German Bight to the northern North Sea by pyrotag sequencing of bacterial 16S rRNA genes and transcripts. Functional profiles were inferred from 16S rRNA data using Tax4Fun. Bacterioplankton communities were dominated by well-known marine lineages including clusters/genera that are affiliated with the Roseobacter group and the Flavobacteria. Variations in community composition and function were significantly explained by measured environmental and microbial properties. Turnover of dissolved free amino acids (DFAA showed the strongest correlation to community composition and function. We applied multinomial models, which enabled us to identify bacterial lineages involved in DFAA turnover. For instance, the genus Planktomarina was more abundant at higher DFAA turnover rates, suggesting its vital role in amino acid degradation. Functional predictions further indicated that Planktomarina is involved in leucine and isoleucine degradation. Overall, our results provide novel insights into the biogeochemical significance of abundant bacterioplankton lineages in the North Sea.

  1. Linking Compositional and Functional Predictions to Decipher the Biogeochemical Significance in DFAA Turnover of Abundant Bacterioplankton Lineages in the North Sea.

    Science.gov (United States)

    Wemheuer, Bernd; Wemheuer, Franziska; Meier, Dimitri; Billerbeck, Sara; Giebel, Helge-Ansgar; Simon, Meinhard; Scherber, Christoph; Daniel, Rolf

    2017-11-05

    Deciphering the ecological traits of abundant marine bacteria is a major challenge in marine microbial ecology. In the current study, we linked compositional and functional predictions to elucidate such traits for abundant bacterioplankton lineages in the North Sea. For this purpose, we investigated entire and active bacterioplankton composition along a transect ranging from the German Bight to the northern North Sea by pyrotag sequencing of bacterial 16S rRNA genes and transcripts. Functional profiles were inferred from 16S rRNA data using Tax4Fun. Bacterioplankton communities were dominated by well-known marine lineages including clusters/genera that are affiliated with the Roseobacter group and the Flavobacteria . Variations in community composition and function were significantly explained by measured environmental and microbial properties. Turnover of dissolved free amino acids (DFAA) showed the strongest correlation to community composition and function. We applied multinomial models, which enabled us to identify bacterial lineages involved in DFAA turnover. For instance, the genus Planktomarina was more abundant at higher DFAA turnover rates, suggesting its vital role in amino acid degradation. Functional predictions further indicated that Planktomarina is involved in leucine and isoleucine degradation. Overall, our results provide novel insights into the biogeochemical significance of abundant bacterioplankton lineages in the North Sea.

  2. Particulate and dissolved spectral absorption on the continental shelf of the southeastern United States

    Science.gov (United States)

    Nelson, James R.; Guarda, Sonia

    1995-05-01

    Visible absorption spectra of particulate and dissolved materials were characterized on the continental shelf off the southeastern United States (the South Atlantic Bight), emphasizing cross-shelf and seasonal variability. A coastal front separates turbid coastal waters from clearer midshelf waters. Spatial and seasonal patterns were evident in absorption coefficients for phytoplankton, detritus, and colored dissolved organic matter (CDOM); spectral shape parameters for CDOM and detritus; and phytoplankton chlorophyll-specific absorption. The magnitude of CDOM absorption reflected seasonal differences in freshwater discharge and the salinity of the midshelf waters. In the spring of 1993 (high discharge), CDOM absorption at 443 nm was >10 times that of total particulate absorption between 12 and 50 km offshore (0.28-0.69 m-1 versus 0.027-0.062 m-1) and up to 10 times the CDOM absorption measured in the previous summer (low discharge). Phytoplankton chlorophyll-specific absorption in the blue increased with distance from shore (from shift in phytoplankton species composition (from predominantly diatoms inshore to a cyanobacteria-dominated assemblage midshelf in summer), pigment packaging, and higher carotenoid:chlorophyll with distance from shore.

  3. A 3000 yr paleostorm record from St. Catherines Island, Georgia

    Science.gov (United States)

    Braun, Erick; Meyer, Brian; Deocampo, Daniel; Kiage, Lawrence M.

    2017-09-01

    Tropical cyclones (hurricanes in the northern hemisphere) are amongst the most devastating of the world's natural disasters and cause billions of dollars in damage every year. Data on the likelihood of a coastal site being struck by a major hurricane strike can potentially aid in planning and mitigation efforts that could save money and lives. However, forecasting requires data that are currently insufficient for the Georgia Bight. This study provides information to enhance the paleohurricane record by analysis of a 467 cm thick vibracore raised from St. Catherines Island, GA. Sediment geochemistry and foraminiferal assemblages indicate deposits attributable to seven paleohurricane events, five of which were likely major hurricanes when they made landfall on St. Catherines. Magnitudes were estimated by comparison to the overwash deposit left by ;The Sea Islands hurricane of 1893;, a major hurricane recorded by the recent sediment of St. Catherines Island. The St. Catherines record also shows a change in the activity levels on the Georgia coast with two distinct activity regimes over the past 3000 years.

  4. The influence of Pacific Equatorial Water on fish diversity in the southern California Current System

    Science.gov (United States)

    McClatchie, Sam; Thompson, Andrew R.; Alin, Simone R.; Siedlecki, Samantha; Watson, William; Bograd, Steven J.

    2016-08-01

    The California Undercurrent transports Pacific Equatorial Water (PEW) into the Southern California Bight from the eastern tropical Pacific Ocean. PEW is characterized by higher temperatures and salinities, with lower pH, representing a source of potentially corrosive (aragonite,Ωaragonite saturation with depth. Although there is substantial variability in PEW presence as measured by spice on the 26.25-26.75 isopycnal layer, as well as in pH and aragonite saturation, we found fish diversity to be stable over the decades 1985-1996 and 1999-2011. We detected significant difference in species structure during the 1998 La Niña period, due to reduced species evenness. Species richness due to rare species was higher during the 1997/1998 El Niño compared to the La Niña but the effect on species structure was undetectable. Lack of difference in the species abundance structure in the decade before and after the 1997/1999 ENSO event showed that the assemblage reverted to its former structure following the ENSO perturbation, indicating resilience. While the interdecadal species structure remained stable, the long tail of the distributions shows that species richness increased between the decades consistent with intrusion of warm water with more diverse assemblages into the southern California region.

  5. Advertising displays of male Musk Ducks indicate population subdivision across the Nullarbor Plain of Australia

    Science.gov (United States)

    McCracken, K.G.; Fullagar, P.J.; Slater, E.C.; Paton, D.C.; Afton, A.D.

    2002-01-01

    Acoustic advertising displays (n=75) of male Musk Ducks Biziura lobata were analysed at ten widely spaced geographic localities in South Australia, Victoria, and Western Australia. Vocalisations differed in a fixed, non-overlapping pattern between allopatric Musk Duck populations in southeastern and southwestern Australia. These findings suggest that Musk Duck populations are subdivided by the Nullarbor Plain, the arid treeless desert at the head of the Great Australian Bight. Three vocalisations performed by male Musk Ducks not previously reported in the literature were documented also. Vocalisations of captive Musk Ducks collected from different geographic regions (southeast and southwest) differed between regions from which captives originally were collected and were unlike those performed by wild birds. Based on calls of immature Musk Ducks, acoustic variation within regional populations and the apparent inability of captive Musk Ducks reared in isolation to develop the wild type adult call, regional dialects seemingly are acquired in a social context by repeated observance of adult males and some combination of social imprinting, learning, or practice.

  6. A numerical model for the whole Wadden Sea: results on the hydrodynamics

    Science.gov (United States)

    Gräwe, Ulf; Duran-Matute, Matias; Gerkema, Theo; Flöser, Götz; Burchard, Hans

    2015-04-01

    A high-resolution baroclinic three-dimensional numerical model for the entire Wadden Sea of the German Bight in the southern North Sea is first validated against field data for surface elevation, current velocity, temperature and salinity at selected stations and then used to calculate fluxes of volume, heat and salt inside the Wadden Sea and the exchange between the Wadden Sea and the adjacent North Sea through the major tidal inlets. The General Estuarine Transport Model (GETM) is simulating the reference years 2009-2011. The numerical grid has a resolution of 200x200m and 30 adaptive vertical layers. It is the final stage of a multi-nested setup, starting from the North Atlantic. The atmospheric forcing is taken from the operational forecast of the German Weather Service. Additionally, the freshwater discharge of 23 local rivers and creeks are included. For validation, we use observations from a ship of opportunity measuring sea surface properties, tidal gauge stations, high frequency of salinity and volume transport estimates for the Mardiep and Spiekeroog inlet. Finally, the estuarine overturning circulation in three tidal gulleys is quantified. Regional differences between the gullies are assessed and drivers of the estuarine circulation are identified. Moreover, we will give a consistent estimate of the tidal prisms for all tidal inlets in the entire Wadden Sea.

  7. Multidecadal fCO2 Increase Along the United States Southeast Coastal Margin

    Science.gov (United States)

    Reimer, Janet J.; Wang, Hongjie; Vargas, Rodrigo; Cai, Wei-Jun

    2017-12-01

    Coastal margins could be hotspots for acidification due to terrestrial-influenced CO2 sources. Currently there are no long-term (>20 years) records from biologically important coastal environments that could demonstrate sea surface CO2 fugacity (fCO2) and pH trends. Here, multidecadal fCO2 trends are calculated from underway and moored time series observations along the United States southeast coastal margin, also referred to as the South Atlantic Bight (SAB). fCO2 trends across the SAB, derived from ˜26 years of cruises and ˜9.5 years from a moored time series, range from 3.0 to 4.5 µatm yr-1, and are greater than the open ocean increases. The pH decline related to the fCO2 increases could be as much as -0.004 yr-1; a rate greater than that expected from atmospheric-influenced pH alone. We provide evidence that fCO2 increases and pH decreases on an ocean margin can be faster than those predicted for the open ocean from atmospheric influence alone. We conclude that a substantial fCO2 increase across the marginal SAB is due to both increasing temperature on the middle and outer shelves, but to lateral land-ocean interactions in the coastal zone and on inner shelf.

  8. Oceanography at coastal scales: Introduction to the special issue on results from the EU FP7 FIELD_AC project

    Science.gov (United States)

    Sánchez-Arcilla, Agustín; Wolf, Judith; Monbaliu, Jaak

    2014-09-01

    The high-resolution and coupled forecasting of wind, waves and currents, in restricted coastal domains, offer a number of important challenges; these limit the quality of predictions, in the present state-of-the-art. This paper presents the main results obtained for such coastal domains, with reference to a variety of modelling suites and observing networks for: a) Liverpool Bay; b) German Bight; c) Gulf of Venice; and d) the Catalan coast. All of these areas are restricted domains, where boundary effects play a significant role in the resulting inner dynamics. This contribution addresses also the themes of the other papers in this Special Issue, ranging from observations to simulations. Emphasis is placed upon the physics controlling such restricted areas. The text deals also with the transfer to end-users and other interested parties, since the requirements on resolution, accuracy and robustness must be linked to their applications. Finally, some remarks are included on the way forward for coastal oceanography and the synergetic combination of in-situ and remote measurements, with high-resolution 3D simulations.

  9. Distribution of POC, PON and particulate Al, Cd, Cr, Cu, Pb, Ti, Zn and δ13C in the English Channel and adjacent areas

    International Nuclear Information System (INIS)

    Dauby, P.; Frankignoulle, M.; Gobert, S.; Bouquegneau, J.M.

    1994-01-01

    A study of the spatial distribution of the total suspended matter and of its elemental composition (C, N and trace metals) has been performed in the English Channel. The Celtic Sea, and the Southern Bight of the North Sea in June and October 1991. South-west to north-east gradients of suspended matter mass and of lithogenic components (Ti an Al) linked to riverine inputs and to depth shallowing, are observed; organic carbon and nitrogen display an opposite distribution pattern and reach a maximum in the Biscay oceanic waters. Cu, Pb and Zn concentrations are highest near industrialized areas and large estuaries, showing the importance of river inputs. In contrast, Cd, Cu and Cr concentrations are markedly elevated in organic-rich suspended matter from waters in which suspended matter loadings are low, suggesting a significant biological uptake. Finally, 13 C/ 12 C analyses reveal the relative importance of coastal or continental inputs in the north-eastern Channel and in the North Sea. (authors). 56 refs., 12 figs., 3 tabs

  10. Reverse transcriptase directs viral evolution in a deep ocean methane seep

    Science.gov (United States)

    Paul, B. G.; Bagby, S. C.

    2013-12-01

    Deep ocean methane seeps are sites of intense microbial activity, with complex communities fueled by aerobic and anaerobic methanotrophy. Methane consumption in these communities has a substantial impact on the global carbon cycle, yet little is known about their evolutionary history or their likely evolutionary trajectories in a warming ocean. As in other marine systems, viral predation and virally mediated horizontal gene transfer are expected to be major drivers of evolutionary change in these communities; however, the host cells' resistance to cultivation has impeded direct study of the viral population. We conducted a metagenomic study of viruses in the anoxic sediments of a deep methane seep in the Santa Monica Basin in the Southern California Bight. We retrieved 1660 partial viral genomes, tentatively assigning 1232 to bacterial hosts and 428 to archaea. One abundant viral genome, likely hosted by Clostridia species present in the sediment, was found to encode a diversity-generating retroelement (DGR), a module for reverse transcriptase-mediated directed mutagenesis of a distal tail fiber protein. While DGRs have previously been described in the viruses of human pathogens, where diversification of viral tail fibers permits infection of a range of host cell types, to our knowledge this is the first description of such an element in a marine virus. By providing a mechanism for massively broadening potential host range, the presence of DGRs in these systems may have a major impact on the prevalence of virally mediated horizontal gene transfer, and even on the phylogenetic distances across which genes are moved.

  11. Modelling and forecasting long-term dynamics of Western Baltic macrobenthic fauna in relation to climate signals and environmental change

    Science.gov (United States)

    Gröger, Joachim; Rumohr, Heye

    2006-05-01

    Long-term macrobenthos data from Kiel Bight in the Western Baltic collected between 1968 and 2000 have been correlated with the winter NAO index (North Atlantic Oscillation Index) and other environmental data such as temperature, salinity and oxygen content in the bottom water in order to detect systematic patterns related to so far unexplained abiotic signals in the dynamics of zoobenthic species assemblages. The benthos data come from a cluster of five stations (Süderfahrt/ Millionenviertel) in Kiel Bay. Our investigations concentrated on the macrobenthic dynamics with a focus on the number of species m - 2 (species richness). Using logarithms and the time series analysis approach of Box/Jenkins (ARIMA modelling, transfer function modelling) it was shown that species richness was strongly influenced by the winter NAO (adjusted for a linear time trend within the 1968-2000 period) and salinity (with a shift/lag of four years). Bootstrapping experiments (i.e. sampling from the error process) and analysis of prediction power (by means of the one- or more-years leaving-out method) showed that the parameter estimates behaved in a stable way, leading to a relatively robust model.

  12. Investigation and evaluation of airborne pollution in the framework of PARCOM (North Sea) and HELCOM (Baltic Sea) - subproject: Measurements of trace metals

    International Nuclear Information System (INIS)

    Schneider, B.

    1993-01-01

    On the basis of measurements of the deposition and concentrations of atmospheric trace metals the annual input of some selected elements (Pb, Zn, Cd, Ni, V) into the North Sea and the Baltic Sea was estimated. For the Baltic Sea, deposition measurements with a buoy system in the Kiel Bight and data from the EGAP(HELCOM)-monitoring network were used. Data from the measurement stations were extrapolated to related sub-basins according to the deposition fields obtained from model calculations (EMEP). For the North Sea, a mean atmospheric trace metal distribution was determined from numerous measurements at a coastal site and over the central North Sea and the annual input was calculated by multiplication with corresponding deposition velocities and scavenging ratios. A comparison of the deposition data based on measurements with those from model calculations show good agreement in the case of Pb in the Baltic Sea as well as in the North Sea. However, for Zn and Cd large discrepancies are observed. Additionally, deposition processes were studied. Scavenging ratios were determined and dry deposition velocities were estimated by the use of a new method for high time resolution measurements of atmospheric trace metal concentrations (impactor/TXRF). (orig.). 9 figs., 14 tabs [de

  13. Climate change-driven cliff and beach evolution at decadal to centennial time scales

    Science.gov (United States)

    Erikson, Li; O'Neill, Andrea; Barnard, Patrick; Vitousek, Sean; Limber, Patrick

    2017-01-01

    Here we develop a computationally efficient method that evolves cross-shore profiles of sand beaches with or without cliffs along natural and urban coastal environments and across expansive geographic areas at decadal to centennial time-scales driven by 21st century climate change projections. The model requires projected sea level rise rates, extrema of nearshore wave conditions, bluff recession and shoreline change rates, and cross-shore profiles representing present-day conditions. The model is applied to the ~470-km long coast of the Southern California Bight, USA, using recently available projected nearshore waves and bluff recession and shoreline change rates. The results indicate that eroded cliff material, from unarmored cliffs, contribute 11% to 26% to the total sediment budget. Historical beach nourishment rates will need to increase by more than 30% for a 0.25 m sea level rise (~2044) and by at least 75% by the year 2100 for a 1 m sea level rise, if evolution of the shoreline is to keep pace with rising sea levels.

  14. Regional monitoring programs in the United States: Synthesis of four case studies from Pacific, Atlantic, and Gulf Coasts

    Science.gov (United States)

    Tango, Peter J.; Schiff, K.; Trowbridge, P.R.; Sherwood, E.T.; Batiuk, R.A.

    2016-01-01

    Water quality monitoring is a cornerstone of environmental protection and ambient monitoring provides managers with the critical data they need to take informed action. Unlike site-specific monitoring that is at the heart of regulatory permit compliance, regional monitoring can provide an integrated, holistic view of the environment, allowing managers to obtain a more complete picture of natural variability and cumulative impacts, and more effectively prioritize management actions. By reviewing four long-standing regional monitoring programs that cover portions of all three coasts in the United States – Chesapeake Bay, Tampa Bay, Southern California Bight, and San Francisco Bay – important insights can be gleaned about the benefits that regional monitoring provides to managers. These insights include the underlying reasons that make regional monitoring programs successful, the challenges to maintain relevance and viability in the face of ever-changing technology, competing demands and shifting management priorities. The lessons learned can help other managers achieve similar successes as they seek to establish and reinvigorate their own monitoring programs.

  15. Multivariate analysis of the influences of oceanic and meteorological processes on suspended particulate matter distributions in Mississippi coastal waters

    Science.gov (United States)

    O'Brien, S. J.; Fitzpatrick, P. J.; Dzwonkowski, B.; Dykstra, S. L.; Wallace, D. J.; Church, I.; Wiggert, J. D.

    2016-02-01

    The Mississippi Sound is influenced by a high volume of sediment discharge from the Biloxi River, Mobile Bay via Pas aux Herons, Pascagoula River, Pearl River, Wolf River, and Lake Pontchartrain through the Rigolets. The river discharge, variable wind speed, wind direction and tides have a significant impact on the turbidity and transport of sediments in the Sound. Level 1 Moderate Resolution Imaging Spectroradiometer (MODIS) data is processed to extract the remote sensing reflectance at the wavelength of 645 nm and binned into an 8-day composite at a resolution of 500 m. The study uses a regional ocean color algorithm to compute suspended particulate matter (SPM) concentration based on these 8-day composite images. Multivariate analysis is applied between the SPM and time series of tides, wind, turbidity and river discharge measured at federal and academic institutions' stations and moorings. The multivariate analysis also includes in situ measurements of suspended sediment concentration and advective exchanges through the Mississippi Sound's tidal inlets between the coastal shelf and the nearshore estuarine waters. Mechanisms underlying the observed spatiotemporal distribution of SPM, including material exchange between the Sound and adjacent shelf waters, will be explored. The results of this study will contribute to current understanding of exchange mechanisms and pathways with the Mississippi Bight via the Mississippi Sound's tidal inlets.

  16. An efficient mode-splitting method for a curvilinear nearshore circulation model

    Science.gov (United States)

    Shi, Fengyan; Kirby, James T.; Hanes, Daniel M.

    2007-01-01

    A mode-splitting method is applied to the quasi-3D nearshore circulation equations in generalized curvilinear coordinates. The gravity wave mode and the vorticity wave mode of the equations are derived using the two-step projection method. Using an implicit algorithm for the gravity mode and an explicit algorithm for the vorticity mode, we combine the two modes to derive a mixed difference–differential equation with respect to surface elevation. McKee et al.'s [McKee, S., Wall, D.P., and Wilson, S.K., 1996. An alternating direction implicit scheme for parabolic equations with mixed derivative and convective terms. J. Comput. Phys., 126, 64–76.] ADI scheme is then used to solve the parabolic-type equation in dealing with the mixed derivative and convective terms from the curvilinear coordinate transformation. Good convergence rates are found in two typical cases which represent respectively the motions dominated by the gravity mode and the vorticity mode. Time step limitations imposed by the vorticity convective Courant number in vorticity-mode-dominant cases are discussed. Model efficiency and accuracy are verified in model application to tidal current simulations in San Francisco Bight.

  17. Intertidal geothermal hot springs as a source of trace elements to the coastal zone: A case study from Bahía Concepción, Gulf of California.

    Science.gov (United States)

    Leal-Acosta, María Luisa; Shumilin, Evgueni; Mirlean, Nicolai; Baturina, Elena Lounejeva; Sánchez-Rodríguez, Ignacio; Delgadillo-Hinojosa, Francisco; Borges-Souza, José

    2018-03-01

    We investigated the influence of the intertidal geothermal hot spring (GHS) on the biogeochemistry of trace elements in Santispac Bight, Bahía Concepción (Gulf of California). The geothermal fluids were enriched in As and Hg mainly in ionic form. The suspended particulate matter of the GHS had elevated enrichment factor (EF) >1 of As, Bi, Cd, Co, Cu, Mn, Mo, Sb, Sn, Sr, Ti, U and Zn. The sediment core from GHS1 had high concentration of As, Hg, C org , S, V, Mo, and U and the extremely high EF of these elements at 8cm of the core. The maximum bioaccumulation of As and Hg was in seaweeds Sargassum sinicola collected near the GHS2. The results confirm the input of trace elements to the coastal zone in Bahía Concepción from geothermal fluids and the evident modification of the chemical composition of the adjacent marine environment. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Passive acoustic monitoring using a towed hydrophone array results in identification of a previously unknown beaked whale habitat.

    Science.gov (United States)

    Yack, Tina M; Barlow, Jay; Calambokidis, John; Southall, Brandon; Coates, Shannon

    2013-09-01

    Beaked whales are diverse and species rich taxa. They spend the vast majority of their time submerged, regularly diving to depths of hundreds to thousands of meters, typically occur in small groups, and behave inconspicuously at the surface. These factors make them extremely difficult to detect using standard visual survey methods. However, recent advancements in acoustic detection capabilities have made passive acoustic monitoring (PAM) a viable alternative. Beaked whales can be discriminated from other odontocetes by the unique characteristics of their echolocation clicks. In 2009 and 2010, PAM methods using towed hydrophone arrays were tested. These methods proved highly effective for real-time detection of beaked whales in the Southern California Bight (SCB) and were subsequently implemented in 2011 to successfully detect and track beaked whales during the ongoing Southern California Behavioral Response Study. The three year field effort has resulted in (1) the successful classification and tracking of Cuvier's (Ziphius cavirostris), Baird's (Berardius bairdii), and unidentified Mesoplodon beaked whale species and (2) the identification of areas of previously unknown beaked whale habitat use. Identification of habitat use areas will contribute to a better understanding of the complex relationship between beaked whale distribution, occurrence, and preferred habitat characteristics on a relatively small spatial scale. These findings will also provide information that can be used to promote more effective management and conservation of beaked whales in the SCB, a heavily used Naval operation and training region.

  19. Levels of dioxin (PCDD/F) and PCBs in a random sample of Australian aquaculture-produced Southern Bluefin Tuna (Thunnus maccoyii)

    Energy Technology Data Exchange (ETDEWEB)

    Padula, D.; Madigan, T.; Kiermeier, A.; Daughtry, B.; Pointon, A. [South Australian Research and Development Inst. (Australia)

    2004-09-15

    To date there has been no published information available on the levels of dioxin (PCDD/F) and PCBs in Australian aquaculture-produced Southern Bluefin Tuna (Thunnus maccoyii). Southern Bluefin Tuna are commercially farmed off the coast of Port Lincoln in the state of South Australia, Australia. This paper reports the levels of dioxin (PCDD/F) and PCBs in muscle tissue samples from 11 randomly sampled aquaculture-produced Southern Bluefin Tuna collected in 2003. Little published data exists on the levels of dioxin (PCDD/F) and PCBs in Australian aquacultureproduced seafood. Wild tuna are first caught in the Great Australian Bight in South Australian waters, and are then brought back to Port Lincoln where they are ranched in sea-cages before being harvested and exported to Japan. The aim of the study was to identify pathways whereby contaminants such as dioxin (PCDD/F) and PCBs may enter the aquaculture production system. This involved undertaking a through chain analysis of the levels of dioxin (PCDD/F) and PCBs in wild caught tuna, seafloor sediment samples from the marine environment, levels in feeds and final harvested exported product. Detailed study was also undertaken on the variation of dioxin (PCDD/F) and PCBs across individual tuna carcases. This paper addresses the levels found in final harvested product. Details on levels found in other studies will be published elsewhere shortly.

  20. Optical properties of humic substances and CDOM: effects of borohydride reduction.

    Science.gov (United States)

    Ma, Jiahai; Del Vecchio, Rossana; Golanoski, Kelli S; Boyle, Erin S; Blough, Neil V

    2010-07-15

    Treatment of Suwanee River humic (SRHA) and fulvic (SRFA) acids, a commercial lignin (LAC), and a series of solid phase extracts (C18) from the Middle Atlantic Bight (MAB extracts) with sodium borohydride (NaBH(4)), a selective reductant of carbonyl-containing compounds including quinones and aromatic ketones, produces a preferential loss of visible absorption (> or = 50% for SRFA) and substantially enhanced, blue-shifted fluorescence emission (2- to 3-fold increase). Comparison of the results with those obtained from a series of model quinones and hydroquinones demonstrates that these spectral changes cannot be assigned directly to the absorption and emission of visible light by quinones/hydroquinones. Instead, these results are consistent with a charge transfer model in which the visible absorption is due primarily to charge transfer transitions arising among hydroxy- (methoxy-) aromatic donors and carbonyl-containing acceptors. Unlike most of the model hydroquinones, the changes in optical properties of the natural samples following NaBH(4) reduction were largely irreversible in the presence of air and following addition of a Cu(2+) catalyst, providing tentative evidence that aromatic ketones (or other similar carbonyl-containing structures) may play a more important role than quinones in the optical properties of these materials.

  1. Optical properties of humic substances and CDOM: relation to structure.

    Science.gov (United States)

    Boyle, Erin S; Guerriero, Nicolas; Thiallet, Anthony; Del Vecchio, Rossana; Blough, Neil V

    2009-04-01

    The spectral dependencies of absorption and fluorescence emission (emission maxima (lamdamax), quantum yields (phi), and mean lifetimes (taum)) were acquired for a commercial lignin, Suwannee River humic (SRHA) and fulvic (SRFA) acids, and a series solid phase extracts (C18) from the Middle Atlantic Bight (MAB extracts). These parameters were compared with the relative average size and total lignin phenol content (TLP). TLP was strongly correlated with absorption at 280 and 355 nm for the MAB extracts, SRHA, and SRFA. The spectral dependence of lamdamax, phi), and taum was very similar for all samples, suggesting a common photophysical and thus structural basis. A strong decrease of phi and taum with increasing average size indicates that intramolecular interactions must be important. When combined with previous work, the results lead us to conclude that the optical properties commonly associated with terrestrial humic substances and chromophoric dissolved organic matter arise primarily from an ensemble of partially oxidized lignins derived from vascular plant sources. Theyfurther provide additional support for an electronic interaction model in which intramolecular energy transfer, excited-state electron transfer, as well as charge transfer likely play important roles in producing the observed optical and photochemical properties of these materials.

  2. Mapping the spawning grounds of North Sea cod (Gadus morhua) by direct and indirect means.

    Science.gov (United States)

    Fox, Clive J; Taylor, Martin; Dickey-Collas, Mark; Fossum, Petter; Kraus, Gerd; Rohlf, Norbert; Munk, Peter; van Damme, Cindy J G; Bolle, Loes J; Maxwell, David L; Wright, Peter J

    2008-07-07

    Despite recent evidence for sub-stock structuring, North Sea cod are assessed as a single unit. As a consequence, knowledge of sub-stock trends is poor. In particular, there are no recent evaluations of which spawning grounds are active. Here we report results from the first ichthyoplankton survey to cover the whole North Sea. Also, this survey, conducted in 2004, was the first to make extensive use of DNA-based molecular methods to unambiguously identify early developmental stage cod eggs. We compare the findings from the plankton survey with estimated egg production inferred from the distribution of mature cod in contemporaneous trawl surveys. Results from both approaches were in general agreement and showed hot spots of egg production around the southern and eastern edges of the Dogger Bank, in the German Bight, the Moray Firth and to the east of the Shetlands. These areas broadly coincide with known spawning locations from the period 1940 to 1970. We were, however, unable to directly detect significant numbers of cod eggs at the historic spawning ground off Flamborough (northeast coast of England). The results demonstrate that most of the major spawning grounds of cod in the North Sea are still active but that some localized populations may have been reduced to the point where it is now difficult to detect the presence of eggs in the plankton.

  3. Comparison of the effects of two bongo net mesh sizes on the estimation of abundance and size of Engraulidae eggs

    Directory of Open Access Journals (Sweden)

    Jana Menegassi del Favero

    2015-06-01

    Full Text Available Abstract Studies of ichthyoplankton retention by nets of different mesh sizes are important because they help in choosing a sampler when planning collection and the establishment of correction factors. These factors make it possible to compare studies performed with nets of different mesh sizes. In most studies of mesh retention of fish eggs, the taxonomic identification is done at the family level, resulting in the loss of detailed information. We separated Engraulidae eggs, obtained with 0.333 mm and 0.505 mm mesh bongo nets at 172 oceanographic stations in the southeastern Brazilian Bight, into four groups based on their morphometric characteristics. The difference in the abundance of eggs caught by the two nets was not significant for those groups with highest volume, types A and B, but in type C (Engraulis anchoita, the most eccentric, and in type D, of the smallest volume, the difference was significant. However, no significant difference was observed in the egg size sampled with each net for E. anchoita and type D, which exhibited higher abundance in the 0.333 mm mesh net and minor axis varying from 0.45-0.71 mm, smaller than the 0.505 mm mesh aperture and the mesh diagonal.

  4. Multi-scale sampling to evaluate assemblage dynamics in an oceanic marine reserve.

    Science.gov (United States)

    Thompson, Andrew R; Watson, William; McClatchie, Sam; Weber, Edward D

    2012-01-01

    To resolve the capacity of Marine Protected Areas (MPA) to enhance fish productivity it is first necessary to understand how environmental conditions affect the distribution and abundance of fishes independent of potential reserve effects. Baseline fish production was examined from 2002-2004 through ichthyoplankton sampling in a large (10,878 km(2)) Southern Californian oceanic marine reserve, the Cowcod Conservation Area (CCA) that was established in 2001, and the Southern California Bight as a whole (238,000 km(2) CalCOFI sampling domain). The CCA assemblage changed through time as the importance of oceanic-pelagic species decreased between 2002 (La Niña) and 2003 (El Niño) and then increased in 2004 (El Niño), while oceanic species and rockfishes displayed the opposite pattern. By contrast, the CalCOFI assemblage was relatively stable through time. Depth, temperature, and zooplankton explained more of the variability in assemblage structure at the CalCOFI scale than they did at the CCA scale. CalCOFI sampling revealed that oceanic species impinged upon the CCA between 2002 and 2003 in association with warmer offshore waters, thus explaining the increased influence of these species in the CCA during the El Nino years. Multi-scale, spatially explicit sampling and analysis was necessary to interpret assemblage dynamics in the CCA and likely will be needed to evaluate other focal oceanic marine reserves throughout the world.

  5. Multi-scale sampling to evaluate assemblage dynamics in an oceanic marine reserve.

    Directory of Open Access Journals (Sweden)

    Andrew R Thompson

    Full Text Available To resolve the capacity of Marine Protected Areas (MPA to enhance fish productivity it is first necessary to understand how environmental conditions affect the distribution and abundance of fishes independent of potential reserve effects. Baseline fish production was examined from 2002-2004 through ichthyoplankton sampling in a large (10,878 km(2 Southern Californian oceanic marine reserve, the Cowcod Conservation Area (CCA that was established in 2001, and the Southern California Bight as a whole (238,000 km(2 CalCOFI sampling domain. The CCA assemblage changed through time as the importance of oceanic-pelagic species decreased between 2002 (La Niña and 2003 (El Niño and then increased in 2004 (El Niño, while oceanic species and rockfishes displayed the opposite pattern. By contrast, the CalCOFI assemblage was relatively stable through time. Depth, temperature, and zooplankton explained more of the variability in assemblage structure at the CalCOFI scale than they did at the CCA scale. CalCOFI sampling revealed that oceanic species impinged upon the CCA between 2002 and 2003 in association with warmer offshore waters, thus explaining the increased influence of these species in the CCA during the El Nino years. Multi-scale, spatially explicit sampling and analysis was necessary to interpret assemblage dynamics in the CCA and likely will be needed to evaluate other focal oceanic marine reserves throughout the world.

  6. Stratified coastal ocean interactions with tropical cyclones

    Science.gov (United States)

    Glenn, S. M.; Miles, T. N.; Seroka, G. N.; Xu, Y.; Forney, R. K.; Yu, F.; Roarty, H.; Schofield, O.; Kohut, J.

    2016-01-01

    Hurricane-intensity forecast improvements currently lag the progress achieved for hurricane tracks. Integrated ocean observations and simulations during hurricane Irene (2011) reveal that the wind-forced two-layer circulation of the stratified coastal ocean, and resultant shear-induced mixing, led to significant and rapid ahead-of-eye-centre cooling (at least 6 °C and up to 11 °C) over a wide swath of the continental shelf. Atmospheric simulations establish this cooling as the missing contribution required to reproduce Irene's accelerated intensity reduction. Historical buoys from 1985 to 2015 show that ahead-of-eye-centre cooling occurred beneath all 11 tropical cyclones that traversed the Mid-Atlantic Bight continental shelf during stratified summer conditions. A Yellow Sea buoy similarly revealed significant and rapid ahead-of-eye-centre cooling during Typhoon Muifa (2011). These findings establish that including realistic coastal baroclinic processes in forecasts of storm intensity and impacts will be increasingly critical to mid-latitude population centres as sea levels rise and tropical cyclone maximum intensities migrate poleward. PMID:26953963

  7. Champacyclin, a New Cyclic Octapeptide from Streptomyces Strain C42 Isolated from the Baltic Sea

    Directory of Open Access Journals (Sweden)

    Alexander Pesic

    2013-12-01

    Full Text Available New isolates of Streptomyces champavatii were isolated from marine sediments of the Gotland Deep (Baltic Sea, from the Urania Basin (Eastern Mediterranean, and from the Kiel Bight (Baltic Sea. The isolates produced several oligopeptidic secondary metabolites, including the new octapeptide champacyclin (1a present in all three strains. Herein, we report on the isolation, structure elucidation and determination of the absolute stereochemistry of this isoleucine/leucine (Ile/Leu = Xle rich cyclic octapeptide champacyclin (1a. As 2D nuclear magnetic resonance (NMR spectroscopy could not fully resolve the structure of (1a, additional information on sequence and configuration of stereocenters were obtained by a combination of multi stage mass spectrometry (MSn studies, amino acid analysis, partial hydrolysis and subsequent enantiomer analytics with gas chromatography positive chmical ionization/electron impact mass spectrometry (GC-PCI/EI-MS supported by comparison to reference dipeptides. Proof of the head-to-tail cyclization of (1a was accomplished by solid phase peptide synthesis (SPPS compared to an alternatively side chain cyclized derivative (2. Champacyclin (1a is likely synthesized by a non-ribosomal peptide synthetase (NRPS, because of its high content of (d-amino acids. The compound (1a showed antimicrobial activity against the phytopathogen Erwinia amylovora causing the fire blight disease of certain plants.

  8. Evaluating VIIRS ocean color products for west coast and Hawaiian waters

    KAUST Repository

    Davis, Curtiss O.

    2013-06-03

    Automated match ups allow us to maintain and improve the ocean color products of current satellite instruments MODIS, and since February 2012 the Visible Infrared Imaging Radiometer Suite (VIIRS). As part of the VIIRS mission Ocean Calibration and Validation Team, we have created a web-based automated match up tool that provides access to searchable fields for date, site, and products, and creates matchups between satellites (MODIS, VIIRS), and in-situ measurements (HyperPRO and SeaPRISM). The goal is to evaluate the standard VIIRS ocean color products produced by the IDPS and available through NOAA’s CLASS data system. Comparisons are made with MODIS data for the same location, and VIIRS data processed using the NRL Automated Processing System (APS) used to produce operational products for the Navy. Results are shown for the first year of VIIRS data matching the satellite data with the data from Platform Eureka SeaPRISM off L. A. Harbor in the Southern California Bight, and HyperPRO data from Station ALOHA near Hawaii. © (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

  9. Analytical characterization of selective benthic flux components in estuarine and coastal waters

    Science.gov (United States)

    King, Jeffrey N.

    2011-01-01

    Benthic flux is the rate of flow across the bed of a water body, per unit area of bed. It is forced by component mechanisms, which interact. For example, pressure gradients across the bed, forced by tide, surface gravity waves, density gradients, bed–current interaction, turbulence, and terrestrial hydraulic gradients, drive an advective benthic flux of water and constituents between estuarine and coastal waters, and surficial aquifers. Other mechanisms also force benthic flux, such as chemical gradients, bioturbation, and dispersion. A suite of component mechanisms force a total benthic flux at any given location, where each member of the suite contributes a component benthic flux. Currently, the types and characteristics of component interactions are not fully understood. For example, components may interact linearly or nonlinearly, and the interaction may be constructive or destructive. Benthic flux is a surface water–groundwater interaction process. Its discharge component to a marine water body is referred to, in some literature, as submarine groundwater discharge. Benthic flux is important in characterizing water and constituent budgets of estuarine and coastal systems. Analytical models to characterize selective benthic flux components are reviewed. Specifically, these mechanisms are for the component associated with the groundwater tidal prism, and forced by surface gravity wave setup, surface gravity waves on a plane bed, and the terrestrial hydraulic gradient. Analytical models are applied to the Indian River Lagoon, Florida; Great South Bay, New York; and the South Atlantic Bight in South Carolina and portions of North Carolina.

  10. Relationship Between Mycorrhizal Associations and Tree Phyto-Sanitary Conditions of Urban Woodlands of Bogota D.C., Colombia

    International Nuclear Information System (INIS)

    Ramos Montano, Carolina; Posada Almanza, Raul H; Ronderos Figueroa, Miguel A; Penagos Canon, Gustavo A

    2010-01-01

    Spore number and root infection by Arbuscular mycorrhizal fungi were evaluated in Eugenia myrtifolia, Ficus soatensis and Croton bogotensis, in parks and green zones of urban woodlands of Bogota D.C, Colombia. The aim was to investigate relations between mycorrhizal associations and tree phyto-sanitary conditions, and effects of two distinct climatic zones. It was demonstrated that plant species and climate are significant sources of variations in the general mycorrhizal state. Eugenia myrtifolia showed the highest degree of root colonization but the lowest number of spores, while C. bogotensis had the opposite response. In general, dry environments favored the mycorrhizal infection levels. By considering overall data, there was a positive relation between the general phytosanitary status of the urban trees and the mycorrhizal colonization. The evaluation of the relationship with the incidence of specific foliar symptoms showed that chlorosis, bight and herbivory maintained a negative relation with the mycorrhization in E. myrtifolia and C. bogotensis. Results suggest that association with AM fungi helps in any way for reducing

  11. Oceanic and atmospheric patterns during spawning periods prior to extreme catches of the Brazilian sardine (Sardinella brasiliensis in the southwest Atlantic

    Directory of Open Access Journals (Sweden)

    Helena Cachanhuk Soares

    2011-07-01

    Full Text Available Relative maxima and minima of landings of Brazilian sardine captured in the Southeast Brazil Bight (SBB were compared with oceanic and atmospheric composites relative to the spawning period in December and January, prior to these landings. Atmospheric and oceanic variables such as wind stress, Ekman transport, mixing index, sea surface temperature (SST, precipitation, outgoing long wave radiation and geopotential height were analyzed, revealing distinct climatological patterns in the SBB for these extreme catches that have not been described before. The system could be characterized by cooler SST composite anomaly (SSTA along the SBB as a response to increased cloud cover and reduced incidence of short-wave radiation, predominating one year before the Brazilian sardine catch maxima. This system can take on a different configuration in which positive SSTA condition in the SBB is associated with a less intense South Atlantic Convergence Zone displaced southwards one year before the period of minimum catch. Our results indicate that the spatial structure of the spawning habitat is influenced by specific ocean-atmosphere interactions rather than simply resulting from the choice of a stable environment. This climatic constraint strongly affects the interannual variability of the Brazilian sardine production.

  12. Distributions and characteristics of dissolved organic matter in temperate coastal waters (Southern North Sea)

    Science.gov (United States)

    Lübben, Andrea; Dellwig, Olaf; Koch, Sandra; Beck, Melanie; Badewien, Thomas H.; Fischer, Sibylle; Reuter, Rainer

    2009-04-01

    The spatial and temporal distributions of chromophoric dissolved organic matter (CDOM) and dissolved organic carbon (DOC) was studied in the East-Frisian Wadden Sea (Southern North Sea) during several cruises between 2002 and 2005. The spatial distribution of CDOM in the German Bight shows a strong gradient towards the coast. Tidal and seasonal variations of dissolved organic matter (DOM) identify freshwater discharge via flood-gates at the coastline and pore water efflux from tidal flat sediments as the most important CDOM sources within the backbarrier area of the Island of Spiekeroog. However, the amount and pattern of CDOM and DOC is strongly affected by various parameters, e.g. changes in the amount of terrestrial run-off, precipitation, evaporation, biological activity and photooxidation. A decoupling of CDOM and DOC, especially during periods of pronounced biological activity (algae blooms and microbial activity), is observed in spring and especially in summer. Mixing of the endmembers freshwater, pore water, and open sea water results in the formation of a coastal transition zone. Whilst an almost conservative behaviour during mixing is observed in winter, summer data point towards non-conservative mixing.

  13. Application of ERTS-1 data to the protection and management of New Jersey's coastal environment

    Science.gov (United States)

    Yunghans, R. S.; Feinberg, E. B.; Wobber, F. J.; Mairs, R. L. (Principal Investigator); Macomber, R. T.; Stanczuk, D.; Stitt, J. A.

    1974-01-01

    The author has identified the following significant results. Rapid access to ERTS data was provided by NASA GSFC for the February 26, 1974 overpass of the New Jersey test site. Forty-seven hours following the overpass computer-compatible tapes were ready for processing at EarthSat. The finished product was ready just 60 hours following the overpass and delivered to the New Jersey Department of Environmental Protection. This operational demonstration has been successful in convincing NJDEP as to the worth of ERTS as an operational monitoring and enforcement tool of significant value to the State. An erosion/ accretion severity index has been developed for the New Jersey shore case study area. Computerized analysis techniques have been used for monitoring offshore waste disposal dumping locations, drift vectors, and dispersion rates in the New York Bight area. A computer shade print of the area was used to identify intensity levels of acid waste. A Litton intensity slice print was made to provide graphic presentation of dispersion characteristics and the dump extent. Continued monitoring will lead to the recommendation and justification of permanent dumping sites which pose no threat to water quality in nearshore environments.

  14. The use of long-term observations in combination with modeling and their effect on the estimation of the North Sea storm surge climate

    Energy Technology Data Exchange (ETDEWEB)

    Aspelien, T.

    2006-07-01

    The aim of this PhD thesis is to design, implement and assess a method to combine long-term observations with multi-decadal model simulations. In this work a computationally cost-efficient nudging method, well suited for multi-decadal simulations, is chosen. First, the nudging method was tested for its sensitivity to different parameters. Then the long-term observations of sea level height from the UK tide gauge Aberdeen were combined with a multi-decadal hindcast for the North Sea. Compared to a control simulation, in which no observed values of sea level height were combined with the model, the nudging method generally improves the modeled water levels with respect to the observed values, especially for surge. The estimation of long-term fluctuations and biases of extreme values of high waters in the nudged simulation are generally considerably improved after nudging and closer to the observed. The effect is largest in the German Bight and at the West coast of Denmark. It is concluded that the cost-efficient nudging method, in which external processes, such as external surges, are additionally taken into account, provides a considerable improvement in reproducing long-term variations and trends, especially for surge. Without additional data from e.g. observed values from tide gauges taken into account, the meteorological induced long-term variations in a hindcast are not fully captured. (orig.)

  15. Transport and transfer rates in the waters of the Continental Shelf. Annual report

    International Nuclear Information System (INIS)

    Biscaye, P.E.

    1978-07-01

    The present contract year has been one of transition from an emphasis on field work and sample gathering to the predominance of sample and data analysis and the formulation of testable hypotheses concerning specific processes in the New York Bight. We have begun to understand the seasonal transition in the role of phytoplankton vs. grazing zooplankton in forming the particles on which some reactive pollutants are removed. Using natural radioactive tracers we have estimated the removal rates of reactive metals from the surface waters and these range over an order of magnitude from most rapid nearshore to least rapid over the upper continental slope. Once removed nearshore, however, these tracers, and the pollutants for which they proxy, do not remain permanently in the sediments but appear to be remobilized (probably by oxidation) during the winter and are reintroduced into the water column. Work on transport and mixing processes of pollutants which are or behave like those in solution has continued along several fronts. Hydrographic data on the structure of the water column continues to give a description of the system that is crucial to understanding geochemical and biological processes which affect pollutants. Hydrographic characterization of water masses from the data sets of cruises has resulted in hypotheses concerning the renewal of shelf water by direct exchange between shelf and upper slope water

  16. Condiciones oceanográficas en isla Gorgona, Pacífico oriental tropical de Colombia Oceanographic conditions off Gorgona Island, eastern tropical Pacific of Colombia

    Directory of Open Access Journals (Sweden)

    Alan Giraldo

    2008-01-01

    Full Text Available La zona de influencia costera de isla Gorgona es un área marina protegida localizada en el Pacífico Oriental Tropical (POT de Colombia. Aunque alberga uno de los arrecifes coralinos más desarrollados del POT, la caracterización de las condiciones oceanógraficas superficiales locales y su variabilidad temporal y espacial han sido escasamente abordadas. Para incrementar el conocimiento sobre la variabilidad de la temperatura y la salinidad en esta localidad se realizaron registros sistemáticos de estas variables durante cuatro periodos (septiembre 2005, diciembre 2005, marzo 2006 y junio 2006, se instalaron sensores de registro continuo de temperatura a f 5 m de profundidad en la zona oriental y occidental de la isla, y se realizó un monitoreo del patrón local de circulación superficial utilizando un perfilador de corrientes (AWAK-ADCP durante junio 2006 y febrero 2007. Se identificaron dos períodos contrastantes para las condiciones oceanógraficas en la capa superficial (0-50 m de la columna de agua: un período cálido y de baja salinidad superficial entre mayo y diciembre (profundidad termoclina 47 m y un período frío y salino entre enero y abril (profundidad termoclina 7,5 m. Se descartó la presencia de proceso local de surgencia y los resultados indicaron una fuerte influencia de procesos de mesoescala (surgencia en el Panamá Bight sobre la variabilidad temporal de las condiciones oceanógraficas en la zona de estudio. En este mismo sentido se sugiere que la variabilidad espacial estaría más asociada a procesos climáticos regionales (patrón de precipitación y la cercanía de la zona de estudio al complejo deltaico río Patía - río Sanquianga.The near shore zone of Gorgona Island is a protected marine area located in the Eastern Tropical Pacific (ETP of Colombia. Although this is home to one of the most developed coral reefs in the ETP, the characteristics of the local oceanographic conditions at the surface and their

  17. Sea floor topography and backscatter intensity of the Historic Area Remediation Site (HARS), offshore of New York, based on multibeam surveys conducted in 1996, 1998, and 2000

    Science.gov (United States)

    Butman, Bradford; Danforth, W.W.; Knowles, S.C.; May, Brian; Serrett, Laurie

    2000-01-01

    An area offshore of Sandy Hook, New Jersey, has been used extensively for disposal of dredged and other materials, derived from the New York/New Jersey Harbor and surrounding areas, since the late 1800's (Figure 1). Between 1976 and 1995, the New York Bight Dredged Material Disposal Site, also known as the Mud Dump Site (Figure 2), received on average about 6 million cubic yards of material each year from federal and private maintenance dredging and from harbor deepening activities (Massa and others, 1996). In September 1997 the Mud Dump Site (MDS) was closed as an official ocean disposal site by the U.S. Environmental Protection Agency (http://www.epa.gov/), and the MDS and surrounding areas were designated as the Historic Area Remediation Site (HARS). The HARS is subdivided into a Primary Remediation Area (PRA, subdivided into 9 cells), a Buffer Zone, and a No-Discharge Zone (Figure 2). The sea floor of the HARS, approximately 9 square nautical miles in area, is being remediated by placing at least a one-meter cap of Category I (clean) dredged material on top of the existing surface sediments that exhibit varying degrees of degradation. (See http://www.nan.usace.army.mil/business/prjlinks/dmmp/benefic/hars.htm)(Category I sediments have no potential short or long-term impacts and are acceptable for unrestricted ocean disposal (EPA, 1996)). About 1.1 million cubic yards of dredged material for remediation was placed in the HARS in 1999, and 2.5 million cubic yards in 2000. Three multibeam echosounder surveys were carried out to map the topography and surficial geology of the HARS. The surveys were conducted November 23 - December 3, 1996, October 26 - November 11, 1998, and April 6 - 30, 2000. The surveys were carried out as part of a larger survey of the Hudson Shelf Valley and adjacent shelf (Butman and others, 1998, (http://pubs.usgs.gov/openfile/of98-616/). This report presents maps showing topography, shaded relief, and backscatter intensity (a measure of sea

  18. Production of Dissolved Organic Matter During Doliolid Feeding

    Science.gov (United States)

    Castellane, N. J.; Paffenhofer, G. A.; Stubbins, A.

    2016-02-01

    The biological carbon pump (BCP) draws carbon dioxide out of the atmosphere and buries it at the seafloor. The efficiency of the BCP is determined in part by the sinking rates of particulate organic carbon (POC) from ocean surface waters. Zooplankton can package POC into fecal pellets with higher sinking rates than their food source (e.g. phytoplankton), increasing the efficiency of the BCP. However, dissolved organic carbon (DOC) is also produced as zooplankton ingest and egest food, reducing the efficiency of BCP. The pelagic tunicate Dolioletta gegenbauri (doliolid) is a gelatinous zooplankton found at high concentrations in shelf waters, including our study site: the South Atlantic Bight. Doliolids are efficient grazers capable of stripping large quantities of phytoplankton from the water column. To determine the balance between pellet formation and DOC production during feeding, doliolids (6-7 mm gonozooids) were placed in natural seawater amended with a live phytoplankton food source and incubated on a plankton wheel. Dissolved organic matter (DOM) released directly to the water as well as the water soluble fraction of pellet organic matter were quantified and optically characterized. Colored dissolved organic matter (CDOM) absorbance and fluorescence spectra revealed that doliolid feeding produces DOM with optical properties that are commonly indicative of newly produced, highly biolabile DOM of microbial origin. Based upon these optical characteristics, doliolid-produced DOM is expected to be highly bio-labile in the environment and therefore rapidly degraded by surface ocean microbes shunting phytoplankton-derived organic carbon out of the BCP and back to dissolved inorganic carbon.

  19. Delta lobe degradation and hurricane impacts governing large-scale coastal behavior, South-central Louisiana, USA

    Science.gov (United States)

    Miner, M.D.; Kulp, M.A.; FitzGerald, D.M.; Flocks, J.G.; Weathers, H.D.

    2009-01-01

    A large deficit in the coastal sediment budget, high rates of relative sea-level rise (???0.9 cm/year), and storm-induced current and wave erosion are forcing barrier shoreface retreat along the periphery of the Mississippi River delta plain. Additionally, conversion of interior wetlands to open water has increased the bay tidal prism, resulting in degradation of barrier islands due to inlet widening, formation of new inlets, and sediment sequestration at ebb-tidal deltas. Single-beam bathymetric surveys along a 165-km stretch of south-central Louisiana barrier coast, from Raccoon Point in Terrebonne Parish to Sandy Point in Plaquemines Parish, were conducted in 2006. These data, combined with historical bathymetry from three time periods (dating to the 1880s), provide a series of digital elevation models that were used to calculate sediment volumetric changes and determine long-term erosional-depositional trends. Dominant patterns during the 125-year period include (1) erosion of ???1.6????????109 m3 from the shoreface, forcing up to 3 km of shoreface retreat, (2) sediment deposition in coastal bights and at ebb-tidal deltas, and (3) a combined increase in tidal inlet cross-sectional area from ???41,400 m2 to ???139,500 m 2. Bathymetric and shoreline change datasets separated by shorter time periods (sub-annual) demonstrate that these long-term trends are driven by processes associated with major hurricane impacts, and that rates of shoreface erosion are an order of magnitude greater during active hurricane seasons compared to long-term trends. ?? 2009 Springer-Verlag.

  20. Secondhand tobacco exposure is associated with nonalcoholic fatty liver disease in children

    International Nuclear Information System (INIS)

    Lin, Connie; Rountree, Carl B.; Methratta, Sosamma; LaRusso, Salvatore; Kunselman, Allen R.; Spanier, Adam J.

    2014-01-01

    Background: Nonalcoholic fatty liver disease (NAFLD) is the leading cause of liver disease in children in the United States, and prevalence rates are rising. Smoking is associated with NAFLD, but the association of secondhand smoke exposure with NAFLD is unknown. Aims: To investigate the association of secondhand tobacco exposure with NAFLD in children. Methods: We surveyed parents/guardians of 304 children aged 3–12 years who had received an abdominal ultrasound at Penn State Hershey Medical Center. The survey addressed demographics, medical history, secondhand tobacco exposure, activity level, screen viewing time and other environmental exposures. A pediatric radiologist and sonographer reviewed the ultrasounds to grade the presence of bight liver compatible with NAFLD. We conducted logistic regression analysis to assess the association of secondhand tobacco exposure and NAFLD. Results: 54% of eligible potential participants responded to the survey. Fatty liver was present in 3% of the children. Increasing child age was associated with increased odds of NAFLD (OR 1.63 95% CI 1.1, 2.4). Reported child obesity was associated with increased odds of NAFLD (OR 44.5 95% CI 5.3, 371.7). The rate of NAFLD was higher in the smoke exposed group (6.7% vs. 1.7%). For every extra pack per day smoked at home, the odds of a child having NAFLD increased 1.8 times (AOR 1.8, 95% CI 1.2, 2.8), and any exposure increased a child's odds of NAFLD four-fold (AOR 4.0, 95% CI 1.02, 15.8). Conclusion: We found an association of secondhand smoke exposure and NAFLD in children. This may represent an area for future prevention efforts. - Highlights: • We evaluated the relation of tobacco exposure with nonalcoholic fatty liver disease. • Tobacco smoke exposure was associated with nonalcoholic fatty liver disease. • Tobacco smoke exposure may be an addressable risk factor

  1. Preparation and characterization of activated carbon from reedy grass leaves by chemical activation with H{sub 3}PO{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Jianzhong, E-mail: xjz8112@sina.com [College of Chemistry and Environmental Science, Hebei University, Baoding 071002, Hebei (China); Chen, Lingzhi [College of Chemistry and Environmental Science, Hebei University, Baoding 071002, Hebei (China); Department of Applied Chemistry, Hengshui University, Hengshui 053000, Hebei (China); Qu, Hongqiang; Jiao, Yunhong; Xie, Jixing [College of Chemistry and Environmental Science, Hebei University, Baoding 071002, Hebei (China); Xing, Guangen [Department of Applied Chemistry, Hengshui University, Hengshui 053000, Hebei (China)

    2014-11-30

    Highlights: • Activated carbons were produced from reedy grass leaves by activation with phosphoric acid. • The activated carbons have a large number of oxygen- and phosphorus-containing surface groups. • The structure of activated carbons was bight fibers features on the surface and the external surface of the activated carbons was slightly corrugated and abundant pores. - Abstract: Activated carbons were produced from reedy grass leaves by chemical activation with H{sub 3}PO{sub 4} in N{sub 2} atmosphere and their characteristics were investigated. The effects of activation temperature and time were examined. Adsorption capacity was demonstrated with BET and iodine number. Micropore volume and pore size distribution of activated carbons were characterized by N{sub 2} adsorption isotherms. The surface area and iodine number of the activated carbons produced at 500 °C for 2 h were 1474 m{sup 2}/g and 1128 mg/g, respectively. Thermal decomposition of pure reedy grass leaves and H{sub 3}PO{sub 4}-impregnated reedy grass leaves have been investigated with thermogravimetric/mass spectroscopy (TG–MS) technique. It was found that the temperature and intensity of maximum evolution of H{sub 2}O and CO{sub 2} of H{sub 3}PO{sub 4}-impregnated reedy grass leaves were lower than that of pure reedy grass leaves. This implies that H{sub 3}PO{sub 4} as an activating reagent changed the thermal degradation of the reedy grass leaves, stabilized the cellulose structure, leading to a subsequent change in the evolution of porosity. The results of X-ray photoelectron spectroscopy and Fourier-infrared spectroscopy analysis indicate that the produced activated carbons have rich functional groups on surface.

  2. OceanGLOBE: an Outdoor Research and Environmental Education Program for K-12 Students

    Science.gov (United States)

    Perry, R. B.; Hamner, W. M.

    2006-12-01

    OceanGLOBE is an outdoor environmental research and education program for upper elementary, middle and high school students, supplemented by online instructional materials that are available without charge to any educator. OceanGLOBE was piloted in 1995 with support from a National Science Foundation Teacher Enhancement project, "Leadership in Marine Science" (award no.ESI-9454413 to UCLA). Continuing support by a second NSF Teacher Enhancement project (award no. ESI-9819424 to UCLA) and by COSEE-West (NSF awards OCE-215506 to UCLA and OCE-0215497 to USC) has enabled OceanGLOBE to expand to a growing number of schools and to provide an increasingly robust collection of marine science instructional materials on its website, http://www.msc.ucla.edu/oceanglobe/ OceanGLOBE provides a mechanism for students to conduct inquiry-based, hands-on marine science research, providing experiences that anchor the national and state science content standards learned in the classroom. Students regularly collect environmental and biological data from a beach site over an extended period of time. In the classroom they organize, graph and analyze their data, which can lead to a variety of student-created science products. Beach research is supported by instructional marine science materials on the OceanGLOBE website. These online materials also can be used in the classroom independent of the field component. Annotated PowerPoint slide shows explain research protocols and provide marine science content. Field guides and photographs of marine organisms (with emphasis on the Southern California Bight) and a growing collection of classroom investigations (applicable to any ocean location) support the science content presented in the beach research program and slide shows. In summary, OceanGLOBE is a comprehensive learning package grounded in hands-on, outdoor marine science research project in which students are the principal investigators. By doing scientific work repetitively over an

  3. Marine Spatial Planning Makes Room for Offshore Aquaculture in a Crowded Coastal Zone

    Science.gov (United States)

    Stevens, J.

    2016-12-01

    Offshore aquaculture is an emerging industry predicted to contribute significantly to global seafood production and food security. However, aquaculture farms can generate conflicts by displacing existing ocean user groups and impacting ecosystems. Further, there are multiple farm types with different seafood species, productivity levels and impacts. Thus, it is important to strategically and simultaneously plan farm type and location in relation to the seascape in order to most effectively maximize aquaculture value while also minimizing conflicts and environmental impacts. We address this problem and demonstrate the value of multi-objective planning with a case study that integrates bioeconomic modeling with ecosystem service tradeoff analysis to inform the marine spatial planning (MSP) of mussel, finfish and kelp aquaculture farms in the already-crowded Southern California Bight (SCB) ecosystem. We considered four user groups predicted to conflict with or be impacted by the three types of aquaculture: wild-capture fisheries, ocean viewshed from coastal properties, marine benthic habitat protection, and risk of disease outbreak between farms. Results indicate that significant conflicts and impacts, expected under conventional planning, can be reduced by strategic planning. For example, 28% of potential mussel farm sites overlap with wild-capture halibut fishery grounds, yet MSP can enable mussel aquaculture to generate up to a third of its total potential industry value without impacting halibut fishery yield. Results also highlight hotspot areas in the SCB most appropriate for each type of aquaculture under MSP, as well as particular mussel, finfish and kelp aquaculture spatial plans that align with legislative regulations on allowable impacts from future aquaculture farms in California. This study comprehensively informs aquaculture farm design in the SCB, and demonstrates the value of multi-objective simultaneous planning as a key component in MSP.

  4. Are extracted materials truly representative of original samples? Impact of C18 extraction on CDOM optical and chemical properties

    Directory of Open Access Journals (Sweden)

    Andrea A Andrew

    2016-02-01

    Full Text Available Some properties of dissolved organic matter (DOM and chromophoric dissolved organic matter (CDOM can be easily measured directly on whole waters, while others require sample concentration and removal of natural salts. To increase CDOM content and eliminate salts, solid phase extraction is often employed. Biases following extraction and elution are inevitable, thus raising the question of how truly representative the extracted material is of the original. In this context, we investigated the wavelength dependence of extraction efficiency for C18 cartridges with respect to CDOM optical properties using samples obtained from the Middle Atlantic Bight (MAB and the Equatorial Atlantic Ocean (EAO. Further, we compared the optical changes of C18 extracts and the corresponding whole water following chemical reduction with sodium borohydride (NaBH4.C18 cartridges preferentially extracted long-wavelength absorbing/emitting material for samples impacted by riverine input. Extraction efficiency overall decreased with offshore distance away from riverine input. Spectral slopes of C18-OM samples were also almost always lower than those of their corresponding CDOM samples supporting the preferential extraction of higher molecular weight absorbing material. The wavelength dependence of the optical properties (absorption, fluorescence emission and quantum yield of the original water samples and their corresponding extracted material were very similar. C18 extracts and corresponding water samples further exhibited comparable optical changes following NaBH4 reduction, thus suggesting a similarity in nature (structure of the optically active extracted material, independent of geographical locale. Altogether, these data suggested a strong similarity between C18 extracts and corresponding whole waters, thus indicating that extracts are representative of the CDOM content of original waters.

  5. Biogeochemistry of southern Australian continental slope sediments

    International Nuclear Information System (INIS)

    Veeh, H.H.; Crispe, A.J.; Heggie, D.T.

    1999-01-01

    Sediment cores from the middle to lower slope of the southern continental margin of Australia between the Great Australian Bight and western Tasmania are compared in terms of marine and terrigenous input signals during the Holocene. The mass accumulation rates of carbonate, organic carbon, biogenic Ba. and Al are corrected for lateral sediment input (focusing), using the inventory of excess 230 Th in the sediment normalised to its known production rate in the water column above each site. The biogenic signal is generally higher in the eastern part of the southern margin probably due to enhanced productivity associated with seasonal upwelling off southeastern South Australia and the proximity of the Subtropical Front, which passes just south of Tasmania. The input of Al, representing the terrigenous signal, is also higher in this region reflecting the close proximity of river runoff from the mountainous catchment of southeastern Australia. The distribution pattern of Mn and authigenic U, together with pore-water profiles of Mn ++ , indicate diagenetic reactions driven by the oxidation of buried organic carbon in an oxic to suboxic environment. Whereas Mn is reduced at depth and diffuses upwards to become immobilised in a Mn-rich surface layer. U is derived from seawater and diffuses downward into the sediment, driven by reduction and precipitation at a depth below the reduction zone of Mn. The estimated removal rate of U from seawater by this process is within the range of U removal measured in hemipelagic sediments from other areas, and supports the proposition that hemipelagic sediments are a major sink of U in the global ocean. Unlike Mn, the depth profile of sedimentary Fe appears to be little affected by diagenesis, suggesting that little of the total Fe inventory in the sediment is remobilised and redistributed as soluble Fe. Copyright (1999) Blackwell Science Pty Ltd

  6. Rapid shelf-wide cooling response of a stratified coastal ocean to hurricanes.

    Science.gov (United States)

    Seroka, Greg; Miles, Travis; Xu, Yi; Kohut, Josh; Schofield, Oscar; Glenn, Scott

    2017-06-01

    Large uncertainty in the predicted intensity of tropical cyclones (TCs) persists compared to the steadily improving skill in the predicted TC tracks. This intensity uncertainty has its most significant implications in the coastal zone, where TC impacts to populated shorelines are greatest. Recent studies have demonstrated that rapid ahead-of-eye-center cooling of a stratified coastal ocean can have a significant impact on hurricane intensity forecasts. Using observation-validated, high-resolution ocean modeling, the stratified coastal ocean cooling processes observed in two U.S. Mid-Atlantic hurricanes were investigated: Hurricane Irene (2011)-with an inshore Mid-Atlantic Bight (MAB) track during the late summer stratified coastal ocean season-and Tropical Storm Barry (2007)-with an offshore track during early summer. For both storms, the critical ahead-of-eye-center depth-averaged force balance across the entire MAB shelf included an onshore wind stress balanced by an offshore pressure gradient. This resulted in onshore surface currents opposing offshore bottom currents that enhanced surface to bottom current shear and turbulent mixing across the thermocline, resulting in the rapid cooling of the surface layer ahead-of-eye-center. Because the same baroclinic and mixing processes occurred for two storms on opposite ends of the track and seasonal stratification envelope, the response appears robust. It will be critical to forecast these processes and their implications for a wide range of future storms using realistic 3-D coupled atmosphere-ocean models to lower the uncertainty in predictions of TC intensities and impacts and enable coastal populations to better respond to increasing rapid intensification threats in an era of rising sea levels.

  7. Effects of wave-induced forcing on a circulation model of the North Sea

    Science.gov (United States)

    Staneva, Joanna; Alari, Victor; Breivik, Øyvind; Bidlot, Jean-Raymond; Mogensen, Kristian

    2017-04-01

    The effect of wind waves on water level and currents during two storms in the North Sea is investigated using a high-resolution NEMO model forced with fluxes and fields from a high-resolution wave model. The additional terms accounting for wave-current interaction that are considered in this study are the Stokes-Coriolis force and the sea-state dependent energy and momentum fluxes. The individual and collective role of these processes is quantified and the results are compared with a control run without wave effects as well as against current and water level measurements from coastal stations. We find a better agreement with observations when the circulation model is forced by sea-state dependent fluxes, especially in extreme events. The two extreme events, the storm Christian (25-27 October 2013), and about a month later, the storm Xaver (5-7 December 2013), induce different wave and surge conditions over the North Sea. Including the wave effects in the circulation model for the storm Xaver raises the modelled surge by more than 40 cm compared with the control run in the German Bight area. For the storm Christian, a difference of 20-30 cm in the surge level between the wave-forced and the stand-alone ocean model is found over the whole southern part of the North Sea. Moreover, the modelled vertical velocity profile fits the observations very well when the wave forcing is accounted for. The contribution of wave-induced forcing has been quantified indicating that this represents an important mechanism for improving water level and current predictions.

  8. Predictability of the California Current System

    Science.gov (United States)

    Miller, Arthur J.; Chereskin, T.; Cornuelle, B. D.; Niiler, P. P.; Moisan, J. R.; Lindstrom, Eric (Technical Monitor)

    2001-01-01

    The physical and biological oceanography of the Southern California Bight (SCB), a highly productive subregion of the California Current System (CCS) that extends from Point Conception, California, south to Ensenada, Mexico, continues to be extensively studied. For example, the California Cooperative Oceanic Fisheries Investigations (CalCOFI) program has sampled this region for over 50 years, providing an unparalleled time series of physical and biological data. However, our understanding of what physical processes control the large-scale and mesoscale variations in these properties is incomplete. In particular, the non-synoptic and relatively coarse spatial sampling (70km) of the hydrographic grid does not completely resolve the mesoscale eddy field (Figure 1a). Moreover, these unresolved physical variations exert a dominant influence on the evolution of the ecosystem. In recent years, additional datasets that partially sample the SCB have become available. Acoustic Doppler Current Profiler (ADCP) measurements, which now sample upper-ocean velocity between stations, and sea level observations along TOPEX tracks give a more complete picture of the mesoscale variability. However, both TOPEX and ADCP are well-sampled only along the cruise or orbit tracks and coarsely sampled in time and between tracks. Surface Lagrangian drifters also sample the region, although irregularly in time and space. SeaWiFS provides estimates of upper-ocean chlorophyll-a (chl-alpha), usually giving nearly complete coverage for week-long intervals, depending on cloud coverage. Historical ocean color data from the Coastal Zone Color Scanner (CZCS) has been used extensively to determine phytoplankton patterns and variability, characterize the primary production across the SCB coastal fronts, and describe the seasonal and interannual variability in pigment concentrations. As in CalCOFI, these studies described much of the observed structures and their variability over relatively large space and

  9. Crude costs: a framework for a full-cost accounting analysis of oil and gas exploration off Cape Breton, Nova Scotia

    International Nuclear Information System (INIS)

    Landon, L.; Pannozzo, L.

    2001-12-01

    Defined as the total quantity of all goods and services produced and the total money earned and spent, the Gross Domestic Product (GDP) is a measure used to determine how well an economy is doing. For its part, the Genuine Progress Index (GPI) measures 26 variables and was first developed in 1995. In Nova Scotia, a set of 20 social, economic and environmental indicators are examined to obtain a better picture of the well-being of the region and determine if the development is sustainable over time. The authors explained their approach based on the use of GPI analysis to assist decision makers in identifying the real costs and benefits of different options applied to the oil and gas exploration situation off Cape Breton, Nova Scotia. The document is divided into five parts as follows: (1) Part 1: introduction, (2) Part 2: natural capital and the impacts of oil and gas development, (3) Part 3: social capital and the economic value of fishing and tourism, (4) Part 4: the real cost of oil and gas, and (5) Part 5: recommendations. Some of the recommendations call for the further study of cumulative and sub-lethal effects from petroleum development, the establishment of Marine Protected Areas preceded by a moratorium on oil and gas exploration in the Southern Gulf of St. Lawrence and Sydney Bight areas until the establishment of the Areas is made, and that future environmental assessments concerning oil and gas development to address the impacts on species and ecosystems as a whole. 209 refs., 11 tabs., 4 figs

  10. Habitat compression and expansion of sea urchins in response to changing climate conditions on the California continental shelf and slope (1994-2013)

    Science.gov (United States)

    Sato, Kirk N.; Levin, Lisa A.; Schiff, Kenneth

    2017-03-01

    Echinoid sea urchins with distributions along the continental shelf and slope of the eastern Pacific often dominate the megafauna community. This occurs despite their exposure to naturally low dissolved oxygen (DO) waters (calcium carbonate (ΩCaCO3<1). Here we present vertical depth distribution and density analyses of historical otter trawl data collected in the Southern California Bight (SCB) from 1994 to 2013 to address the question: Do changes in echinoid density and species' depth distributions along the continental margin in the SCB reflect observed secular or interannual changes in climate? Deep-dwelling burrowing urchins (Brissopsis pacifica, Brisaster spp. and Spatangus californicus), which are adapted to low-DO, low-pH conditions appeared to have expanded their vertical distributions and populations upslope over the past decade (2003-2013), and densities of the deep pink urchin, Strongylocentrotus fragilis, increased significantly in the upper 500 m of the SCB. Conversely, the shallower urchin, Lytechinus pictus, exhibited depth shoaling and density decreases within the upper 200 m of the SCB from 1994 to 2013. Oxygen and pH in the SCB also vary inter-annually due to varying strengths of the El Niño Southern Oscillation (ENSO). Changes in depth distributions and densities were correlated with bi-monthly ENSO climate indices in the region. Our results suggest that both a secular trend in ocean deoxygenation and acidification and varying strength of ENSO may be linked to echinoid species distributions and densities, creating habitat compression in some and habitat expansion in others. Potential life-history mechanisms underlying depth and density changes observed over these time periods include migration, mortality, and recruitment. These types of analyses are needed for a broad suite of benthic species in order to identify and manage climate-sensitive species on the margin.

  11. Stormwater Runoff Plumes in Southern California Detected with Satellite SAR and MODIS Imagery - Areas of Increased Contamination Risk

    Science.gov (United States)

    Trinh, R. C.; Holt, B.; Gierach, M.

    2016-12-01

    Coastal pollution poses both a major health and environmental hazard, not only for beachgoers and coastal communities, but for marine organisms as well. Stormwater runoff is the largest source of pollution in the coastal waters of the Southern California Bight (SCB). The SCB is the final destination of four major urban watersheds and associated rivers, Ballona Creek, the Los Angeles River, the San Gabriel River, and the Santa Ana River, which act as channels for runoff and pollution during and after episodic rainstorms. Previous studies of SCB water quality have made use of both fine resolution Synthetic Aperture Radar (SAR) imagery and wide-swath medium resolution optical "ocean color" imagery from SeaWiFS and MODIS. In this study, we expand on previous SAR efforts, compiling a more extensive collection of multi-sensor SAR data, spanning from 1992 to 2014, analyzing the surface slick component of stormwater plumes. We demonstrate the use of SAR data in early detection of coastal stormwater plumes, relating plume extent to cumulative river discharge, and shoreline fecal bacteria loads. Intensity maps of the primary extent and direction of plumes were created, identifying coastal areas that may be subject to the greatest risk of environmental contamination. Additionally, we illustrate the differences in the detection of SAR surface plumes with the sediment-related discharge plumes derived from MODIS ocean color imagery. Finally, we provide a concept for satellite monitoring of stormwater plumes, combining both optical and radar sensors, to be used to guide the collection of in situ water quality data and enhance the assessment of related beach closures.

  12. Priority volatile organic compounds in surface waters of the southern North Sea

    International Nuclear Information System (INIS)

    Huybrechts, Tom; Dewulf, Jo; Langenhove, Herman van

    2005-01-01

    The occurrence of 25 volatile organic compounds (VOCs) was studied from April 1998 to October 2000 in the southern North Sea. Target VOCs were selected from lists of priority pollutants for the marine environment and included, e.g., chlorinated short-chain hydrocarbons (CHCs), monocyclic aromatic hydrocarbons (MAHs), and chlorinated monocyclic aromatic hydrocarbons (CMAHs). Water samples were taken from the Channel, the Belgian Continental Shelf, the mouth of the Scheldt estuary and the Southern Bight, and were analysed by purge-and-trap and high-resolution gas chromatography-mass spectrometry. All data were produced by analyses deemed 'in control' by a rigorous quality assurance/quality control program provided by QUASIMEME (Quality Assurance of Information for Marine Environmental Monitoring in Europe). Chloroform and trichloroethene were commonly detected at concentrations up to 1900 and 270 ng l -1 , respectively. The other CHCs were generally found below 5 ng l -1 , and rarely exceeded 10 ng l -1 . Concentrations of MAHs were at least one order of magnitude higher than those of the CHCs. The higher levels were attributed to anthropogenic emissions from oil-related activities in coastal areas. CMAHs, except chlorobenzene and 1,4-dichlorobenzene, were hardly detected in North Sea waters. The levels of several CHCs and MAHs were shown to decrease compared to previous investigations in 1994-1995, probably as a result of on-going emission reduction efforts. The occurrence of 1,1,1-trichloroethane, for instance, was substantially reduced since the Montreal Protocol was implemented in 1995. - Volatile aromatics are a major group of volatile organic compounds in the North Sea, and are attributed to discharges from shipping and oil related activities

  13. Automated sensor networks to advance ocean science

    Science.gov (United States)

    Schofield, O.; Orcutt, J. A.; Arrott, M.; Vernon, F. L.; Peach, C. L.; Meisinger, M.; Krueger, I.; Kleinert, J.; Chao, Y.; Chien, S.; Thompson, D. R.; Chave, A. D.; Balasuriya, A.

    2010-12-01

    The National Science Foundation has funded the Ocean Observatories Initiative (OOI), which over the next five years will deploy infrastructure to expand scientist’s ability to remotely study the ocean. The deployed infrastructure will be linked by a robust cyberinfrastructure (CI) that will integrate marine observatories into a coherent system-of-systems. OOI is committed to engaging the ocean sciences community during the construction pahse. For the CI, this is being enabled by using a “spiral design strategy” allowing for input throughout the construction phase. In Fall 2009, the OOI CI development team used an existing ocean observing network in the Mid-Atlantic Bight (MAB) to test OOI CI software. The objective of this CI test was to aggregate data from ships, autonomous underwater vehicles (AUVs), shore-based radars, and satellites and make it available to five different data-assimilating ocean forecast models. Scientists used these multi-model forecasts to automate future glider missions in order to demonstrate the feasibility of two-way interactivity between the sensor web and predictive models. The CI software coordinated and prioritized the shared resources that allowed for the semi-automated reconfiguration of assett-tasking, and thus enabled an autonomous execution of observation plans for the fixed and mobile observation platforms. Efforts were coordinated through a web portal that provided an access point for the observational data and model forecasts. Researchers could use the CI software in tandem with the web data portal to assess the performance of individual numerical model results, or multi-model ensembles, through real-time comparisons with satellite, shore-based radar, and in situ robotic measurements. The resulting sensor net will enable a new means to explore and study the world’s oceans by providing scientists a responsive network in the world’s oceans that can be accessed via any wireless network.

  14. A Comparison of Recent Organic and Inorganic Carbon Isotope Records: Why Do They Covary in Some Settings and Not In Others?

    Science.gov (United States)

    Oehlert, A. M.; Swart, P. K.

    2013-12-01

    Covariance between inorganic and organic δ13C records has been used to determine whether a deposit has been altered by diagenesis, how the dynamics of the global carbon cycle changed during the production of the sediments in the deposit, and also for chronostratigraphic correlations. Although covariant records are observed in the ancient geologic record in a variety of depositional environments, such comparisons are not widely applied to modern deposits where definitive data regarding sediment producers, sea level fluctuations, and changes in the global carbon cycle are available. This study uses paired δ13C records from cores collected by the Ocean Drilling Program from three modern periplatform settings (the Great Bahama Bank, the Great Australian Bight, and the Great Barrier Reef), and two pelagic settings (the Walvis Ridge, and the Madingley Rise). These sites were selected in order to assess the influence of several different environmental factors including; sediment and organic matter producers, sediment mineralogy, margin architecture, sea level oscillations, and sediment transport pathways. In the three periplatform settings, multiple cores arranged in a margin to basin transect were analyzed in order to provide insights into the effects of downslope sediment transport. The preliminary results of this study suggest that sea level oscillations and margin architecture may artificially generate a covarying relationship in periplatform sediments that is unrelated to changes in the global carbon cycle. Furthermore, preliminary results from the Walvis Ridge and the Madingley Rise sediments suggest that the relationship between inorganic and organic δ13C records may not always exhibit a positive covariance as is currently assumed for pelagic carbonates.

  15. Constrained body shape among highly genetically divergent allopatric lineages of the supralittoral isopod Ligia occidentalis (Oniscidea).

    Science.gov (United States)

    Santamaria, Carlos A; Mateos, Mariana; DeWitt, Thomas J; Hurtado, Luis A

    2016-03-01

    Multiple highly divergent lineages have been identified within Ligia occidentalis sensu lato, a rocky supralittoral isopod distributed along a ~3000 km latitudinal gradient that encompasses several proposed marine biogeographic provinces and ecoregions in the eastern Pacific. Highly divergent lineages have nonoverlapping geographic distributions, with distributional limits that generally correspond with sharp environmental changes. Crossbreeding experiments suggest postmating reproductive barriers exist among some of them, and surveys of mitochondrial and nuclear gene markers do not show evidence of hybridization. Populations are highly isolated, some of which appear to be very small; thus, the effects of drift are expected to reduce the efficiency of selection. Large genetic divergences among lineages, marked environmental differences in their ranges, reproductive isolation, and/or high isolation of populations may have resulted in morphological differences in L. occidentalis, not detected yet by traditional taxonomy. We used landmark-based geometric morphometric analyses to test for differences in body shape among highly divergent lineages of L. occidentalis, and among populations within these lineages. We analyzed a total of 492 individuals from 53 coastal localities from the southern California Bight to Central Mexico, including the Gulf of California. We conducted discriminant function analyses (DFAs) on body shape morphometrics to assess morphological variation among genetically differentiated lineages and their populations. We also tested for associations between phylogeny and morphological variation, and whether genetic divergence is correlated to multivariate morphological divergence. We detected significant differences in body shape among highly divergent lineages, and among populations within these lineages. Nonetheless, neither lineages nor populations can be discriminated on the basis of body shape, because correct classification rates of cross

  16. Are extracted materials truly representative of original samples? Impact of C18 extraction on CDOM optical and chemical properties

    Science.gov (United States)

    Andrew, Andrea; Del Vecchio, Rossana; Zhang, Yi; Subramaniam, Ajit; Blough, Neil

    2016-02-01

    Some properties of dissolved organic matter (DOM) and chromophoric dissolved organic matter (CDOM) can be easily measured directly on whole waters, while others require sample concentration and removal of natural salts. To increase CDOM content and eliminate salts, solid phase extraction is often employed. Biases following extraction and elution are inevitable, thus raising the question of how truly representative the extracted material is of the original. In this context, we investigated the wavelength dependence of extraction efficiency for C18 cartridges with respect to CDOM optical properties using samples obtained from the Middle Atlantic Bight (MAB) and the Equatorial Atlantic Ocean (EAO). Further, we compared the optical changes of C18 extracts and the corresponding whole water following chemical reduction with sodium borohydride (NaBH4). C18 cartridges preferentially extracted long-wavelength absorbing/emitting material for samples impacted by riverine input. Extraction efficiency overall decreased with offshore distance away from riverine input. Spectral slopes of C18-OM samples were also almost always lower than those of their corresponding CDOM samples supporting the preferential extraction of higher molecular weight absorbing material. The wavelength dependence of the optical properties (absorption, fluorescence emission and quantum yield) of the original water samples and their corresponding extracted material were very similar. C18 extracts and corresponding water samples further exhibited comparable optical changes following NaBH4 reduction, thus suggesting a similarity in nature (structure) of the optically active extracted material, independent of geographical locale. Altogether, these data suggested a strong similarity between C18 extracts and corresponding whole waters, thus indicating that extracts are representative of the CDOM content of original waters.

  17. Mössbauer spectroscopy and X-ray fluorescence studies on sediments from the methanic zone of the Helgoland mud area, North Sea

    Energy Technology Data Exchange (ETDEWEB)

    Costa, B. F. O. [University of Coimbra, CFisUC, Physics Department (Portugal); Blumers, M.; Shylin, S. I.; Ksenofontov, V. [Johannes Gutenberg University, Institute for Inorganic and Analytical Chemistry (Germany); Oni, O. [University of Bremen, Microbial Ecophysiology group, Faculty of Biology/Chemistry (Germany); Kasten, S.; Fischer, D. [University of Bremen, MARUM, Center for Marine Environmental Sciences (Germany); Wagenknecht, L. [Alfred Wegener Institute Helmholtz Center for Polar and Marine Research (Germany); Kulkarni, A.; Friedrich, M. W. [University of Bremen, Microbial Ecophysiology group, Faculty of Biology/Chemistry (Germany); Klingelhöfer, G., E-mail: klingel@mail.uni-mainz.de [Johannes Gutenberg University, Institute for Inorganic and Analytical Chemistry (Germany)

    2016-12-15

    {sup 57}Fe Mössbauer spectroscopy (MS) and X-ray fluorescence spectroscopy (XRF) were used to determine the identity of iron(III) oxides in surface (top 30 cm ) and subsurface (> 30 cm – 500 cm)sediments from the Helgoland mud area in the German Bight of the North Sea. A 500 cm-long sediment core was cut in 25 cm sections while only the top 10 cm of a 30 cm-long sediment core was sampled. Using a MIMOS spectrometer, MS spectra were recorded at 293 K (RT) in backscattering geometry. At 80 K and 5.5 K, MS analysis was carried out in transmission geometry. At RT and 80 K only illite was observed, but at 5.5 K lepidocrocite was revealed in the MS spectra. The relation between Fe(III) and Fe(II) doublets of illite did not significantly vary with depth, but the relative amount of lepidocrocite increased with depth reaching about 24 % of iron phases, as revealed by MS. XRF measurements showed that the amount of Fe in the sediments varied with depth but was always less than 4 % of total elemental composition. The main component of the sediment was silica and its depth profile alternated with those of other elements, especially aluminium and iron. It was observed that elevated concentrations of dissolved iron in the subsurface sediment of the Helgoland mud area correlated with the depth-wise distribution of distinct microbial populations presumably due to microbial reduction of excess bioavailable iron minerals such as lepidocrocite. These results are thus, important in the context of microbe-mineral interactions in marine sediments as iron oxides are an electron acceptor for microbial anaerobic respiration.

  18. Mercury-cycling in surface waters and in the atmosphere - species analysis for the investigation of transformation and transport properties of mercury

    International Nuclear Information System (INIS)

    Ebinghaus, R.; Hintelmann, H.; Wilken, R.D.

    1994-01-01

    The river Elbe has been one of the most contaminated rivers with regard to mercury for many years. In 1991 a length-profile has been measured for mercury and methylmercury (CH 3 Hg + ) from Obristvi, Czech Republic, to the German bight. Total mercury has been measured by cold vapor atomic absorption spectrometry (CVAAS). The organo mercury compounds have been separated by high performance liquid chromatography (HPLC) connected on-line to an atomic fluorescence spectrometer (AFS) by a continuous flow-system. Total mercury up to 120 mg Hg + /kg and CH 3 Hg + concentrations up to 130 μg CH 3 Hg + /kg could be detected in special sites. The formation of CH 3 Hg + in sediments can be caused besides the methylation of mercury, by sulphate reducing or methanogenic bacteria and transmethylation reactions with organometals. Atmospheric mercury concentrations have been measured at three different European sites. Samples have been collected on gold-coated glass balls or on quartz wool, respectively. After thermal desorption mercury has been determined using the two step amalgamation technique with AFS detection. Compared to natural background concentrations of total gaseous mercury (TGM), slightly increased levels could be detected at a rural site in Germany. This increase can probably be explained by long-range transport processes. Within the vicinity of a inactivated mercury production plant high concentrations of up to 13.5 ng/m 3 particle associated mercury (Hg part ) have been detected. Consequently, dry deposition of mercury in the particulate form can intensify the total deposition flux close to Hg-emitting sources. (orig.)

  19. Time series pCO2 at a coastal mooring: Internal consistency, seasonal cycles, and interannual variability

    Science.gov (United States)

    Reimer, Janet J.; Cai, Wei-Jun; Xue, Liang; Vargas, Rodrigo; Noakes, Scott; Hu, Xinping; Signorini, Sergio R.; Mathis, Jeremy T.; Feely, Richard A.; Sutton, Adrienne J.; Sabine, Christopher; Musielewicz, Sylvia; Chen, Baoshan; Wanninkhof, Rik

    2017-08-01

    Marine carbonate system monitoring programs often consist of multiple observational methods that include underway cruise data, moored autonomous time series, and discrete water bottle samples. Monitored parameters include all, or some of the following: partial pressure of CO2 of the water (pCO2w) and air, dissolved inorganic carbon (DIC), total alkalinity (TA), and pH. Any combination of at least two of the aforementioned parameters can be used to calculate the others. In this study at the Gray's Reef (GR) mooring in the South Atlantic Bight (SAB) we: examine the internal consistency of pCO2w from underway cruise, moored autonomous time series, and calculated from bottle samples (DIC-TA pairing); describe the seasonal to interannual pCO2w time series variability and air-sea flux (FCO2), as well as describe the potential sources of pCO2w variability; and determine the source/sink for atmospheric pCO2. Over the 8.5 years of GR mooring time series, mooring-underway and mooring-bottle calculated-pCO2w strongly correlate with r-values > 0.90. pCO2w and FCO2 time series follow seasonal thermal patterns; however, seasonal non-thermal processes, such as terrestrial export, net biological production, and air-sea exchange also influence variability. The linear slope of time series pCO2w increases by 5.2 ± 1.4 μatm y-1 with FCO2 increasing 51-70 mmol m-2 y-1. The net FCO2 sign can switch interannually with the magnitude varying greatly. Non-thermal pCO2w is also increasing over the time series, likely indicating that terrestrial export and net biological processes drive the long term pCO2w increase.

  20. Characterizing wave- and current- induced bottom shear stress: U.S. middle Atlantic continental shelf

    Science.gov (United States)

    Dalyander, P. Soupy; Butman, Bradford; Sherwood, Christopher R.; Signell, Richard P.; Wilkin, John L.

    2013-01-01

    Waves and currents create bottom shear stress, a force at the seabed that influences sediment texture distribution, micro-topography, habitat, and anthropogenic use. This paper presents a methodology for assessing the magnitude, variability, and driving mechanisms of bottom stress and resultant sediment mobility on regional scales using numerical model output. The analysis was applied to the Middle Atlantic Bight (MAB), off the U.S. East Coast, and identified a tidally-dominated shallow region with relatively high stress southeast of Massachusetts over Nantucket Shoals, where sediment mobility thresholds are exceeded over 50% of the time; a coastal band extending offshore to about 30 m water depth dominated by waves, where mobility occurs more than 20% of the time; and a quiescent low stress region southeast of Long Island, approximately coincident with an area of fine-grained sediments called the “Mud Patch”. The regional high in stress and mobility over Nantucket Shoals supports the hypothesis that fine grain sediment winnowed away in this region maintains the Mud Patch to the southwest. The analysis identified waves as the driving mechanism for stress throughout most of the MAB, excluding Nantucket Shoals and sheltered coastal bays where tides dominate; however, the relative dominance of low-frequency events varied regionally, and increased southward toward Cape Hatteras. The correlation between wave stress and local wind stress was lowest in the central MAB, indicating a relatively high contribution of swell to bottom stress in this area, rather than locally generated waves. Accurate prediction of the wave energy spectrum was critical to produce good estimates of bottom shear stress, which was sensitive to energy in the long period waves.

  1. Simulating the impact of the entrainment of winter flounder larvae

    International Nuclear Information System (INIS)

    Hess, K.W.; Sissenwine, M.P.; Saila, S.B.

    1975-01-01

    The transport of winter flounder larvae around the Millstone Point, Conn. Area by the action of tidal currents and diffusion was simulated by computer to predict the numbers which could be entrained during the operation of a local nuclear power station. A tidal hydrodynamic model with variable depth was employed to simulate currents and water levels. These techniques provided input to a transport model which simulated the concentration of larvae. A larval source in a tributary river was simulated for twenty tidal cycles, with and without entrainment. The results indicated that the reduction in winter flounder larvae near Millstone Point at the end of the pelagic stage (period during which larvae are likely to be entrained) was less than 1 percent when it was assumed that larvae have little chance of returning once lost from Millstone bight. In order to assess the effect of a 1 percent reduction in recruitment of winter flounder larvae to the benthic phase of their life cycle, the local population was simulated by a model in which year-classes and the total egg production were represented by compartments. Each year-class grew, produced eggs, suffered natural and fishing mortality according to information derived from the literature. The effect of power plant entrainment was incorporated by reducing the number of recruits to year-class I that would normally result from a specific level of egg production. For a 1 percent reduction in recruitment due to power plant entrainment, a potential 6 percent decrease in total population size following 35 years of operation was indicated. (U.S.)

  2. Energy Optimal Path Planning: Integrating Coastal Ocean Modelling with Optimal Control

    Science.gov (United States)

    Subramani, D. N.; Haley, P. J., Jr.; Lermusiaux, P. F. J.

    2016-02-01

    A stochastic optimization methodology is formulated for computing energy-optimal paths from among time-optimal paths of autonomous vehicles navigating in a dynamic flow field. To set up the energy optimization, the relative vehicle speed and headings are considered to be stochastic, and new stochastic Dynamically Orthogonal (DO) level-set equations that govern their stochastic time-optimal reachability fronts are derived. Their solution provides the distribution of time-optimal reachability fronts and corresponding distribution of time-optimal paths. An optimization is then performed on the vehicle's energy-time joint distribution to select the energy-optimal paths for each arrival time, among all stochastic time-optimal paths for that arrival time. The accuracy and efficiency of the DO level-set equations for solving the governing stochastic level-set reachability fronts are quantitatively assessed, including comparisons with independent semi-analytical solutions. Energy-optimal missions are studied in wind-driven barotropic quasi-geostrophic double-gyre circulations, and in realistic data-assimilative re-analyses of multiscale coastal ocean flows. The latter re-analyses are obtained from multi-resolution 2-way nested primitive-equation simulations of tidal-to-mesoscale dynamics in the Middle Atlantic Bight and Shelbreak Front region. The effects of tidal currents, strong wind events, coastal jets, and shelfbreak fronts on the energy-optimal paths are illustrated and quantified. Results showcase the opportunities for longer-duration missions that intelligently utilize the ocean environment to save energy, rigorously integrating ocean forecasting with optimal control of autonomous vehicles.

  3. Laboratory-measured grazing and ingestion rates of the salp, Thalia democratica Forskal, and the doliolid, Dolioletta gegenbauri Uljanin (Tunicata, Thaliacea)

    Energy Technology Data Exchange (ETDEWEB)

    Deibel, D.

    1982-01-01

    Grazing and ingestion rates of laboratory-born Thalia democratica aggregates and Dolioletta gegenbauri gonozooids, phorozooids and oozooids were determined while fed Isochrysis galbana (4-5 ..mu..m diameter) alone or in combination with Peridinium trochoideum (16-18 ..mu..m diameter) at concentrations of 0.15-0.70 mm/sup 3/ x 1/sup -1/. Grazing rates (ml x zooid/sup -1/ x 24 h/sup -1/) ranged from 10 to 355, and at zooid weights greater than 5..mu..g carbon were in order oozooid > gonozooid > aggregate. Grazing rates increased exponentially with increasing zooid weight. Weight-specific grazing rates (ml x ..mu..gC/sup -1/ x 24 h/sup -1/) were independent of the four-fold initial food concentration. Mean weight-specific grazing rates increased linearly with increasing zooid weight for the aggregates and oozooids, but gonozooid mean rates were independent of zooid weight. Aggregate and gonozooid ingestion rates (10/sup 6/..mu..m/sup 3/ x zooid/sup -1/ x 24 h/sup -1/) ranged from 4 to 134 while oozooid rates ranged from 3 to 67. All ingestion rates were independent of the initial food concentration but increased linearly with increasing zooid weight at similar rates. All mean weight-specific ingestion rates (ml x ..mu..gC/sup -1/ x 24 h/sup -1/) were independent of zooid weight. The mean aggregate daily ration (..mu..gC ingested x ..mu..g body C/sup -1/) was 59% and the mean doliolid ration was 132%. Field studies indicate that normal concentrations of D. gegenbauri in the Georgia Bight clear their resident water volume (1 m/sup 3/) in about 4 months, but that highly concentrated, swarm populations which occur along thermohaline fronts clear their resident water volume in less than 1 day.

  4. CDOM-DOC relationship in contrasted coastal waters: implication for DOC retrieval from ocean color remote sensing observation.

    Science.gov (United States)

    Vantrepotte, Vincent; Danhiez, François-Pierre; Loisel, Hubert; Ouillon, Sylvain; Mériaux, Xavier; Cauvin, Arnaud; Dessailly, David

    2015-01-12

    Increasing our knowledge on dissolved organic carbon (DOC) spatio-temporal distribution in the coastal ocean represents a crucial challenge for better understanding the role of these ecosystems in the global oceanic carbon cycle. The assessment of DOC concentration from the absorption properties of the colored part of the dissolved organic matter (a(cdom)) was investigated from an extensive data set covering a variety of coastal environments. Our results confirmed that variation in the a(cdom)(412) to DOC ratio (a*(cdom)(412)) can be depicted from the CDOM spectral slope in the UV domain (S(275-295)). They also evidenced that regional first order variation in both a*(cdom)(412) and S(275-295) are highly correlated to variation in a(cdom)(412). From these observations, generalized relationships for estimating a*(cdom)(412) from S(275-295) or a(cdom)(412) were parameterized from our development sites (N = 158; English Channel, French Guiana, Hai Phong Bay) and tested against an independent data set covering others coastal regions (N = 223; French Polynesia, Rhone River estuary, Gulf of Maine, Chesapeake Bay, Southern Middle Atlantic Bight) demonstrating the possibility to derive DOC estimates from in situ CDOM optical properties with an average accuracy of ~16% over very contrasted coastal environments (with DOC ranging from 50 to 250 µmol.L(-1)). The applicability of these generalized approaches was evaluated in the context of ocean color remote sensing observation emphasizing the limits of S(275-295)-based formulations and the potential for a(cdom)-based approaches to represent a compelling alternative for assessing synoptic DOC distribution.

  5. Are Extracted Materials Truly Representative of Original Samples? Impact of C18 Extraction on CDOM Optical and Chemical Properties.

    Science.gov (United States)

    Andrew, Andrea A; Del Vecchio, Rossana; Zhang, Yi; Subramaniam, Ajit; Blough, Neil V

    2016-01-01

    Some properties of dissolved organic matter (DOM) and chromophoric dissolved organic matter (CDOM) can be easily measured directly on whole waters, while others require sample concentration and removal of natural salts. To increase CDOM content and eliminate salts, solid phase extraction (SPE) is often employed. Biases following extraction and elution are inevitable, thus raising the question of how truly representative the extracted material is of the original. In this context, we investigated the wavelength dependence of extraction efficiency for C18 cartridges with respect to CDOM optical properties using samples obtained from the Middle Atlantic Bight (MAB) and the Equatorial Atlantic Ocean (EAO). Further, we compared the optical changes of C18 extracts and the corresponding whole water following chemical reduction with sodium borohydride (NaBH4). C18 cartridges preferentially extracted long-wavelength absorbing/emitting material for samples impacted by riverine input. Extraction efficiency overall decreased with offshore distance away from riverine input. Spectral slopes of C18-OM samples were also almost always lower than those of their corresponding CDOM samples supporting the preferential extraction of higher molecular weight absorbing material. The wavelength dependence of the optical properties (absorption, fluorescence emission, and quantum yield) of the original water samples and their corresponding extracted material were very similar. C18 extracts and corresponding water samples further exhibited comparable optical changes following NaBH4 reduction, thus suggesting a similarity in nature (structure) of the optically active extracted material, independent of geographical locale. Altogether, these data suggested a strong similarity between C18 extracts and corresponding whole waters, thus indicating that extracts are representative of the CDOM content of original waters.

  6. Factors that control the stable carbon isotopic composition of methane produced in an anoxic marine sediment

    Science.gov (United States)

    Alperin, M. J.; Blair, Neal E.; Albert, D. B.; Hoehler, T. M.; Martens, C. S.

    1993-01-01

    emitted from undisturbed Cape Lookout Bight sediment.

  7. Temporal and vertical distributions of bacterioplankton at the Gray's Reef National Marine Sanctuary.

    Science.gov (United States)

    Lu, Xinxin; Sun, Shulei; Zhang, Yu-Qin; Hollibaugh, James T; Mou, Xiaozhen

    2015-02-01

    Large spatial scales and long-term shifts of bacterial community composition (BCC) in the open ocean can often be reliably predicted based on the dynamics of physical-chemical variables. The power of abiotic factors in shaping BCC on shorter time scales in shallow estuarine mixing zones is less clear. We examined the diurnal variation in BCC at different water depths in the spring and fall of 2011 at a station in the Gray's Reef National Marine Sanctuary (GRNMS). This site is located in the transition zone between the estuarine plume and continental shelf waters of the South Atlantic Bight. A total of 234,516 pyrotag sequences of bacterial 16S rRNA genes were recovered; they were taxonomically affiliated with >200 families of 23 bacterial phyla. Nonmetric multidimensional scaling analysis revealed significant differences in BCC between spring and fall samples, likely due to seasonality in the concentrations of dissolved organic carbon and nitrate plus nitrite. Within each diurnal sampling, BCC differed significantly by depth only in the spring and differed significantly between day and night only in the fall. The former variation largely tracked changes in light availability, while the latter was most correlated with concentrations of polyamines and chlorophyll a. Our results suggest that at the GRNMS, a coastal mixing zone, diurnal variation in BCC is attributable to the mixing of local and imported bacterioplankton rather than to bacterial growth in response to environmental changes. Our results also indicate that, like members of the Roseobacter clade, SAR11 bacteria may play an important role in processing dissolved organic material in coastal oceans. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  8. Secondhand tobacco exposure is associated with nonalcoholic fatty liver disease in children

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Connie [College of Medicine, Penn State University Hershey Medical Center, 500 University Drive, PO Box 850, Hershey, PA 17033-0850 (United States); Rountree, Carl B. [Department of Pediatrics, Penn State University Hershey Medical Center, 500 University Drive, PO Box 850, Hershey, PA 17033-0850 (United States); Department of Pediatrics, Bon Secour St. Mary' s Hospital, 5801 Bremo Rd, Richmond, VA 23226 (United States); Methratta, Sosamma [Department of Pediatrics, Penn State University Hershey Medical Center, 500 University Drive, PO Box 850, Hershey, PA 17033-0850 (United States); Department of Radiology, Penn State University Hershey Medical Center, 500 University Drive, PO Box 850, Hershey, PA 17033-0850 (United States); LaRusso, Salvatore [Department of Radiology, Penn State University Hershey Medical Center, 500 University Drive, PO Box 850, Hershey, PA 17033-0850 (United States); Kunselman, Allen R. [Department of Public Health Sciences, Penn State University Hershey Medical Center, 500 University Drive, PO Box 850, Hershey, PA 17033-0850 (United States); Spanier, Adam J., E-mail: aspanier@hmc.psu.edu [Department of Pediatrics, Penn State University Hershey Medical Center, 500 University Drive, PO Box 850, Hershey, PA 17033-0850 (United States); Department of Public Health Sciences, Penn State University Hershey Medical Center, 500 University Drive, PO Box 850, Hershey, PA 17033-0850 (United States)

    2014-07-15

    Background: Nonalcoholic fatty liver disease (NAFLD) is the leading cause of liver disease in children in the United States, and prevalence rates are rising. Smoking is associated with NAFLD, but the association of secondhand smoke exposure with NAFLD is unknown. Aims: To investigate the association of secondhand tobacco exposure with NAFLD in children. Methods: We surveyed parents/guardians of 304 children aged 3–12 years who had received an abdominal ultrasound at Penn State Hershey Medical Center. The survey addressed demographics, medical history, secondhand tobacco exposure, activity level, screen viewing time and other environmental exposures. A pediatric radiologist and sonographer reviewed the ultrasounds to grade the presence of bight liver compatible with NAFLD. We conducted logistic regression analysis to assess the association of secondhand tobacco exposure and NAFLD. Results: 54% of eligible potential participants responded to the survey. Fatty liver was present in 3% of the children. Increasing child age was associated with increased odds of NAFLD (OR 1.63 95% CI 1.1, 2.4). Reported child obesity was associated with increased odds of NAFLD (OR 44.5 95% CI 5.3, 371.7). The rate of NAFLD was higher in the smoke exposed group (6.7% vs. 1.7%). For every extra pack per day smoked at home, the odds of a child having NAFLD increased 1.8 times (AOR 1.8, 95% CI 1.2, 2.8), and any exposure increased a child's odds of NAFLD four-fold (AOR 4.0, 95% CI 1.02, 15.8). Conclusion: We found an association of secondhand smoke exposure and NAFLD in children. This may represent an area for future prevention efforts. - Highlights: • We evaluated the relation of tobacco exposure with nonalcoholic fatty liver disease. • Tobacco smoke exposure was associated with nonalcoholic fatty liver disease. • Tobacco smoke exposure may be an addressable risk factor.

  9. Methylmercury compounds - main areas of contamination on a transsect of the river Elbe

    International Nuclear Information System (INIS)

    Hintelmann, H.; Wilken, R.D.

    1994-01-01

    The river Elbe and some of its tributaries are worldwide one of the most mercury polluted river systems. They are not only polluted by inorganic mercury compouns, but the contents of the highly toxic methylmercury compounds are also elevated. In order to determine the low levels of methylmercury compounds usually observed in sediments, a new HPLC/AFS-coupling was developed. In an oxidation/reduction interface the mercury species eluting from the HPLC collumn are transformed continuously to elemental mercury, which is then detected on-line by a highly sensitive atomic fluorescence spectrophotometer. The detection limit for the analysis of organic mercury species in sediments after extraction with hydrochloric acid/toluene, preconcentration and determination by HPLC/AFS is 0.1 μg/kg d. w. Hence, uncontaminated samples with very low methylmercury compounds contents could also be successfully analyzed. Main areas of total mercury contamination in the Elbe system were in the tributary rivers Saale and Mulde, with contents of up to 112 mg/kg d. w. but important emitters were also found in the Czech Republic (CR). This contamination was followed downstream to the Hamburg area and dropped to a background level of 0.06 mg/kg d. w. in the German Bight. The highest content of methylmercury compounds (119 μg/kg d. w.) was measured again in the river Mulde. The levels of methylmercury compounds were generally high at sites where the microbial activity was stimulated by high contents of organic matter, indicating a biotic methylation of mercury. The organic substrates originated either from municipal (sewage plants) or industrial sources (pulp mill effluents). (orig.) [de

  10. Spatio-temporal variability of internal waves in the northern Gulf of Mexico studied with the Navy Coastal Ocean Model, NCOM

    Science.gov (United States)

    Cambazoglu, M. K.; Jacobs, G. A.; Howden, S. D.; Book, J. W.; Arnone, R.; Soto Ramos, I. M.; Vandermeulen, R. A.; Greer, A. T.; Miles, T. N.

    2016-02-01

    Internal waves enhance mixing in the upper ocean, transport nutrients and plankton over the water column and across the shelf from deeper waters to shallower coastal areas, and could also transport pollutants such as hydrocarbons onshore during an oil spill event. This study aims to characterize internal waves in the northern Gulf of Mexico (nGoM) and investigate the possible generation and dissipation mechanisms using a high-resolution (1-km) application of the Navy Coastal Ocean Model (NCOM). Three dimensional model products are used to detect the propagation patterns of internal waves. The vertical structure of internal waves is studied and the role of stratification is analyzed by looking at the temperature, salinity and velocity variations along the water column. The model predictions suggest the generation of internal waves on the continental shelf, therefore the role of ocean bottom topography interacting with tides and general circulation features such as the Loop Current Eddy front, on the internal wave generation will be discussed. The time periods of internal wave occurrences are identified from model predictions and compared to satellite ocean color imagery. Further data analysis, e.g. Fourier analysis, is implemented to determine internal wavelengths and frequencies and to determine if the response of internal waves are at tidal periods or at different frequencies. The atmospheric forcing provided to NCOM and meteorological data records are analyzed to define the interaction between wind forcing and internal wave generation. Wavelet analysis characterizes the ocean response to atmospheric events with periodic frequencies. Ocean color satellite imagery was used to visualize the location of the Mississippi river plume (and other oceanic features) and compared to the model predictions because the enhanced stratification from freshwater plumes which propagate across the Mississippi Bight can provide favorable conditions in coastal waters for internal wave

  11. The big squeeze: ecosystem change and contraction of habitat for newly discovered deep-water reefs off the U.S. West Coast

    Science.gov (United States)

    Wickes, L.; Etnoyer, P. J.; Lauermann, A.; Rosen, D.

    2016-02-01

    Cold-water reefs are fragile, complex ecosystems that extend into the bathyal depths of the ocean, creating three dimensional structure and habitat for a diversity of deep-water invertebrates and fishes. The cold waters of the California Current support a diverse assemblage of these corals at relatively shallow depths close to shore. At these depths and locations the communities face a multitude of stressors, including low carbonate saturations, hypoxia, changing temperature, and coastal pollution. The current study employed ROV surveys (n=588, 2003-2015) to document the distribution of deep-sea corals in the Southern California Bight, including the first description of a widespread reef-building coral in the naturally acidified waters off the U.S. West Coast. We provide empirical evidence of species survival in the corrosive waters (Ωarag 0.67-1.86), but find loss of reef integrity. Recent publications have implied acclimation, resistance, and resilience of cold-water reef-building corals to ocean acidification, but results of this study indicate a cost to skeletal framework development with a subsequent loss of coral habitat. While ocean acidification and declines in oxygen are expected to further impinge on Lophelia at depth (𝑥̅=190 m), surface warming and coastal polution may affect shallower populations and mesophotic reef assemblages, resulting in a contraction of available coral habitat. Recent observations of die offs of gorgonians and antipatharians from surveys in shallow (50 m) and deep water (500 m) provide compelling evidence of ongoing ecosystem changes. Concurrent losses in habitat quality in deep and mesophotic waters suggest that corals may be "squeezed" into a more restricted depth range. New monitoring efforts aim to characterize the health and condition of deep corals with respect to gradients in carbonate chemistry, coastal pollution and changing temperatures, to assess vulnerability and both current and future habitat suitability.

  12. Colwellia psychrerythraea strains from distant deep sea basins show adaptation to local conditions

    Directory of Open Access Journals (Sweden)

    Stephen M Techtmann

    2016-05-01

    Full Text Available Many studies have shown that microbes, which share nearly identical 16S rRNA genes, can have highly divergent genomes. Microbes from distinct parts of the ocean also exhibit biogeographic patterning. Here we seek to better understand how certain microbes from the same species have adapted for growth under local conditions. The phenotypic and genomic heterogeneity of three strains of Colwellia psychrerythraea was investigated in order to understand adaptions to local environments. Colwellia are psychrophilic heterotrophic marine bacteria ubiquitous in cold marine ecosystems. We have recently isolated two Colwellia strains: ND2E from the Eastern Mediterranean and GAB14E from the Great Australian Bight. The 16S rRNA sequence of these two strains were greater than 98.2% identical to the well-characterized C. psychrerythraea 34H, which was isolated from arctic sediments. Salt tolerance, and carbon source utilization profiles for these strains were determined using Biolog Phenotype Microarrays’. These strains exhibited distinct salt tolerance, which was not associated with the salinity of sites of isolation. The carbon source utilization profiles were distinct with less than half of the tested carbon sources being metabolized by all three strains. Whole genome sequencing revealed that the genomes of these three strains were quite diverse with some genomes having up to 1600 strain-specific genes. Many genes involved in degrading strain-specific carbon sources were identified. There appears to be a link between carbon source utilization and location of isolation with distinctions observed between the Colwellia isolate recovered from sediment compared to water column isolates.

  13. Mechanisms controlling the intra-annual mesoscale variability of SST and SPM in the southern North Sea

    Science.gov (United States)

    Pietrzak, Julie D.; de Boer, Gerben J.; Eleveld, Marieke A.

    2011-04-01

    Thermal and optical remote sensing data were used to investigate the spatial and temporal distribution of sea surface temperature (SST) and of suspended particulate matter (SPM) in the southern North Sea. Monthly SST composites showed pronounced seasonal warming of the southern North Sea and delineated the English coastal and continental coastal waters. The East-Anglia Plume is the dominant feature of the English coastal waters in the winter and autumn SPM composites, and the Rhine region of freshwater influence (ROFI), including the Flemish Banks, is the dominant feature of the continental waters. These mesoscale spatial structures are also influenced by the evolution of fronts, such as the seasonal front separating well-mixed water in the southern Bight, from the seasonally stratified central North Sea waters. A harmonic analysis of the SST and SPM images showed pronounced seasonal variability, as well as spring-neap variations in the level of tidal mixing in the East Anglia Plume, the Rhine ROFI and central North Sea. The harmonic analysis indicates the important role played by the local meteorology and tides in governing the SST and near-surface SPM concentrations in the southern North Sea. In the summer, thermal stratification affects the visibility of SPM to satellite sensors in the waters to the north of the Flamborough and Frisian Fronts. Haline stratification plays an important role in the visibility of SPM in the Rhine ROFI throughout the year. When stratified, both regions typically exhibit low surface SPM values. A numerical model study, together with the harmonic analysis, highlights the importance of tides and waves in controlling the stratification in the southern North Sea and hence the visibility of SPM.

  14. Mitochondrial Genetic Structure and Matrilineal Origin of White Sharks, Carcharodon carcharias, in the Northeastern Pacific: Implications for Their Conservation.

    Science.gov (United States)

    Oñate-González, Erick C; Rocha-Olivares, Axayácatl; Saavedra-Sotelo, Nancy C; Sosa-Nishizaki, Oscar

    2015-01-01

    White sharks (Carcharodon carcharias, WS henceforth) are globally and regionally threatened. Understanding their patterns of abundance and connectivity, as they relate to habitat use, is central for delineating conservation units and identifying priority areas for conservation. We analyzed mitochondrial data to test the congruence between patterns of genetic connectivity and of individual movements in the Northeastern Pacific (NEP) and to trace the matrilineal origin of immature WS from coastal California and Baja California to adult aggregation areas. We analyzed 186 mitochondrial control region sequences from sharks sampled in Central California (CC; n = 61), Southern California Bight (SCB; n = 25), Baja California Pacific coast (BCPC; n = 9), Bahía Vizcaíno (BV; n = 39), Guadalupe Island (GI; n = 45), and the Gulf of California (GC; n = 7). Significant mitochondrial differentiation between adult aggregation areas (CC, GI) revealed two reproductive populations in the NEP. We found general concordance between movement patterns of young and adult WS with genetic results. Young sharks from coastal California and Baja California were more likely born from females from GI. Mitochondrial differentiation of young-of-the-year from SCB and BV suggests philopatry to nursery areas in females from GI. These results provide a genetic basis of female reproductive behavior at a regional scale and point to a preponderance of sharks from GI in the use of the sampled coastal region as pupping habitat. These findings should be considered in Mexican and US management and conservation strategies of the WS NEP population. © The American Genetic Association 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  15. Winter atmospheric circulation signature for the timing of the spring bloom of diatoms in the North Sea

    Science.gov (United States)

    Lohmann, Gerrit; Wiltshire, Karen

    2015-04-01

    Analysing long-term diatom data from the German Bight and observational climate data for the period 1962-2005, we found a close connection of the inter-annual variation of the timing of the spring bloom with the boreal winter atmospheric circulation. We examined the fact that high diatom counts of the spring bloom tended to occur later when the atmospheric circulation was characterized by winter blocking over Scandinavia. The associated pattern in the sea level pressure showed a pressure dipole with two centres located over the Azores and Norway and was tilted compared to the North Atlantic Oscillation. The bloom was earlier when the cyclonic circulation over Scandinavia allowed an increased inflow of Atlantic water into the North Sea which is associated with clearer, more marine water, and warmer conditions. The bloom was later when a more continental atmospheric flow from the east was detected. At Helgoland Roads, it seems that under turbid water conditions (= low light) zooplankton grazing can affect the timing of the phytoplankton bloom negatively. Warmer water temperatures will facilitate this. Under clear water conditions, light will be the main governing factor with regard to the timing of the spring bloom. These different water conditions are shown here to be mainly related to large-scale weather patterns. We found that the mean diatom bloom could be predicted from the sea level pressure one to three months in advance. Using historical pressure data, we derived a proxy for the timing of the spring bloom over the last centuries, showing an increased number of late (proxy-) blooms during the eighteenth century when the climate was considerably colder than today. We argue that these variations are important for the interpretation of inter-annual to centennial variations of biological processes. This is of particular interest when considering future scenarios, as well to considerations on past and future effects on the primary production and food webs.

  16. The influence of the hydrologic cycle on the extent of sea ice with climatic implications

    Science.gov (United States)

    Dean, Kenneson G.; Stringer, William J.; Searcy, Craig

    1993-01-01

    Multi-temporal satellite images, field observations, and field measurements were used to investigate the mechanisms by which sea ice melts offshore from the Mackenzie River delta. Advanced Very High Resolution Radiometer (AVHRR) satellite data recorded in 1986 were analyzed. The satellite data were geometrically corrected and radiometrically calibrated so that albedo and temperature values could be extracted. The investigation revealed that sea ice melted approximately 2 weeks earlier offshore from the Mackenzie River delta than along coasts where river discharge is minimal or non-existent. There is significant intra-delta variability in the timing and patterns of ice melt. An estimation of energy flux indicates that 30 percent more of the visible wavelength energy and 25 percent more of the near-infrared wavelength energy is absorbed by water offshore of the delta compared to coastal areas with minimal river discharge. The analysis also revealed that the removal of sea ice involves the following: over-ice-flooding along the coast offshore from river delta channels; under-ice flow of 'warm' river water; melting and calving of the fast ice; and, the formation of a bight in the pack ice edge. Two stages in the melting of sea ice were identified: (1) an early stage where heat is supplied to overflows largely by solar radiation, and (2) a later stage where heat is supplied by river discharge in addition to solar radiation. A simple thermodynamic model of the thaw process in the fast ice zone was developed and parameterized based on events recorded by the satellite images. The model treats river discharge as the source of sensible heat at the base of the ice cover. The results of a series of sensitivity tests to assess the influence of river discharge on the near shore ice are presented.

  17. Transport processes near coastal ocean outfalls

    Science.gov (United States)

    Noble, M.A.; Sherwood, C.R.; Lee, Hooi-Ling; Xu, Jie; Dartnell, P.; Robertson, G.; Martini, M.

    2001-01-01

    The central Southern California Bight is an urbanized coastal ocean where complex topography and largescale atmospheric and oceanographic forcing has led to numerous sediment-distribution patterns. Two large embayments, Santa Monica and San Pedro Bays, are connected by the short, very narrow shelf off the Palos Verdes peninsula. Ocean-sewage outfalls are located in the middle of Santa Monica Bay, on the Palos Verdes shelf and at the southeastern edge of San Pedro Bay. In 1992, the US Geological Survey, together with allied agencies, began a series of programs to determine the dominant processes that transport sediment and associated pollutants near the three ocean outfalls. As part of these programs, arrays of instrumented moorings that monitor currents, waves, water clarity, water density and collect resuspended materials were deployed on the continental shelf and slope information was also collected on the sediment and contaminant distributions in the region. The data and models developed for the Palos Verdes shelf suggest that the large reservoir of DDT/DDE in the coastal ocean sediments will continue to be exhumed and transported along the shelf for a long time. On the Santa Monica shelf, very large internal waves, or bores, are generated at the shelf break. The near-bottom currents associated with these waves sweep sediments and the associated contaminants from the shelf onto the continental slope. A new program underway on the San Pedro shelf will determine if water and contaminants from a nearby ocean outfall are transported to the local beaches by coastal ocean processes. The large variety of processes found that transport sediments and contaminants in this small region of the continental margin suggest that in regions with complex topography, local processes change markedly over small spatial scales. One cannot necessarily infer that the dominant transport processes will be similar even in adjacent regions.

  18. Deciding Where to Burn: Stakeholder Priorities for Prescribed Burning of a Fire-Dependent Ecosystem

    Directory of Open Access Journals (Sweden)

    Jennifer K. Costanza

    2011-03-01

    Full Text Available Multiagency partnerships increasingly work cooperatively to plan and implement fire management. The stakeholders that comprise such partnerships differ in their perceptions of the benefits and risks of fire use or nonuse. These differences inform how different stakeholders prioritize sites for burning, constrain prescribed burning, and how they rationalize these priorities and constraints. Using a survey of individuals involved in the planning and implementation of prescribed fire in the Onslow Bight region of North Carolina, we examined how the constraints and priorities for burning in the longleaf pine (Pinus palustris ecosystem differed among three stakeholder groups: prescribed burn practitioners from agencies, practitioners from private companies, and nonpractitioners. Stakeholder groups did not differ in their perceptions of constraints to burning, and development near potentially burned sites was the most important constraint identified. The top criteria used by stakeholders to decide where to burn were the time since a site was last burned, and a site's ecosystem health, with preference given to recently burned sites in good health. Differences among stakeholder groups almost always pertained to perceptions of the nonecological impacts of burning. Prescribed burning priorities of the two groups of practitioners, and particularly practitioners from private companies, tended to be most influenced by nonecological impacts, especially through deprioritization of sites that have not been burned recently or are in the wildland-urban interface (WUI. Our results highlight the difficulty of burning these sites, despite widespread laws in the southeast U.S. that limit liability of prescribed burn practitioners. To avoid ecosystem degradation on sites that are challenging to burn, particularly those in the WUI, conservation partnerships can facilitate demonstration projects involving public and private burn practitioners on those sites. In summary

  19. Fish Ecology and Evolution in the World's Oxygen Minimum Zones and Implications of a Warming Ocean

    Science.gov (United States)

    Gallo, N.; Navarro, E. C.; Yazzie, A. T.; Barry, J. P.; Levin, L. A.

    2016-02-01

    Predicting how demersal fish communities will respond as hypoxic areas expand with climate change requires an understanding of how existing oxygen gradients influence the abundance, diversity, and trophic ecology of demersal fish communities. A literature review of studies from continental margins with oxygen minimum zones in the Pacific, Atlantic, and Indian Ocean, is combined with new data from research cruises to the Gulf of California and the US West Coast, to examine how hypoxic areas influence the structure and function of demersal fish communities. Oxygen minimum zones (OMZs) are deep-sea environments where organisms experience chronic hypoxic and suboxic conditions and have persisted over much longer timescales than coastal eutrophication-induced hypoxic zones, allowing for the evolution of adaptations to low oxygen conditions. While coastal studies have found that fish are one of the most hypoxia-intolerant groups, representative demersal fish species in the orders Cottiformes, Scorpaeniformes, Pleuronectiformes, Gobiiformes, Perciformes, Lophiiformes, Carcharhiniformes, Ophidiiformes, Myxiniformes, and Gadiformes have evolved to exploit physiologically extreme OMZ environments and are important components of the benthic community. In OMZs, certain fish species are some of the most hypoxia-tolerant members of the megafauna community, present even under extremely low oxygen conditions (< 5 µmol/kg) where most invertebrates are absent, though these communities are typically characterized by single-species dominance. To explore differences in the trophic ecology of these "hypoxia-tolerant" fish communities, stable isotope and gut content analysis are used to compare the Southern California Bight OMZ core fish community to the hypoxia-intolerant upper slope fish community. Results show that fish living in the OMZ core have significantly enriched δ13C and δ15N signatures and feed on different prey items.

  20. Optimal design criteria - prediction vs. parameter estimation

    Science.gov (United States)

    Waldl, Helmut

    2014-05-01

    G-optimality is a popular design criterion for optimal prediction, it tries to minimize the kriging variance over the whole design region. A G-optimal design minimizes the maximum variance of all predicted values. If we use kriging methods for prediction it is self-evident to use the kriging variance as a measure of uncertainty for the estimates. Though the computation of the kriging variance and even more the computation of the empirical kriging variance is computationally very costly and finding the maximum kriging variance in high-dimensional regions can be time demanding such that we cannot really find the G-optimal design with nowadays available computer equipment in practice. We cannot always avoid this problem by using space-filling designs because small designs that minimize the empirical kriging variance are often non-space-filling. D-optimality is the design criterion related to parameter estimation. A D-optimal design maximizes the determinant of the information matrix of the estimates. D-optimality in terms of trend parameter estimation and D-optimality in terms of covariance parameter estimation yield basically different designs. The Pareto frontier of these two competing determinant criteria corresponds with designs that perform well under both criteria. Under certain conditions searching the G-optimal design on the above Pareto frontier yields almost as good results as searching the G-optimal design in the whole design region. In doing so the maximum of the empirical kriging variance has to be computed only a few times though. The method is demonstrated by means of a computer simulation experiment based on data provided by the Belgian institute Management Unit of the North Sea Mathematical Models (MUMM) that describe the evolution of inorganic and organic carbon and nutrients, phytoplankton, bacteria and zooplankton in the Southern Bight of the North Sea.

  1. Fine-scale variability of isopycnal salinity in the California Current System

    Science.gov (United States)

    Itoh, Sachihiko; Rudnick, Daniel L.

    2017-09-01

    This paper examines the fine-scale structure and seasonal fluctuations of the isopycnal salinity of the California Current System from 2007 to 2013 using temperature and salinity profiles obtained from a series of underwater glider surveys. The seasonal mean distributions of the spectral power of the isopycnal salinity gradient averaged over submesoscale (12-30 km) and mesoscale (30-60 km) ranges along three survey lines off Monterey Bay, Point Conception, and Dana Point were obtained from 298 transects. The mesoscale and submesoscale variance increased as coastal upwelling caused the isopycnal salinity gradient to steepen. Areas of elevated variance were clearly observed around the salinity front during the summer then spread offshore through the fall and winter. The high fine-scale variances were observed typically above 25.8 kg m-3 and decreased with depth to a minimum at around 26.3 kg m-3. The mean spectral slope of the isopycnal salinity gradient with respect to wavenumber was 0.19 ± 0.27 over the horizontal scale of 12-60 km, and 31%-35% of the spectra had significantly positive slopes. In contrast, the spectral slope over 12-30 km was mostly flat, with mean values of -0.025 ± 0.32. An increase in submesoscale variability accompanying the steepening of the spectral slope was often observed in inshore areas; e.g., off Monterey Bay in winter, where a sharp front developed between the California Current and the California Under Current, and the lower layers of the Southern California Bight, where vigorous interaction between a synoptic current and bottom topography is to be expected.

  2. Comparison of fishes taken by a sportfishing party vessel around oil platforms and adjacent natural reefs near Santa Barbara, California

    International Nuclear Information System (INIS)

    Love, M.S.; Westphal, W.

    1990-01-01

    Since 1958, 29 oil platforms have been sited in the southern California Bight of which 28 still remain in place. However, little is known of the fish populations surrounding these structures, particularly those sited in water deeper than 30 m. In the course of research on the Santa Barbara, California, party vessel sport fishery, it was noted that the platforms off Santa Barbara supported considerable sportfishing activity. Those platforms, located to the southeast of Santa Barbara in depths of 48-62 m, were particularly important and were fished intensively for various rockfishes (genus Sebastes). When fishing a platform, the vessel pulled up to within 5-10 m of a platform and drifts along one side, with the vessel operator using intermittent power to keep it near the structure. Most of the desirable species, particularly rockfishes, remained close to the platforms, rarely venturing more than perhaps 20 m from the structure. The party vessels also spent considerable time fishing over nearby natural reefs. In this survey, it was noted that there appeared to be differences in species catch composition and fish size between oil platforms and these natural reefs. Increased offshore oil drilling off California has raised interest in the role platforms play in marine systems. Questions have been raised regarding what fish live around platforms, how these structures influence populations over surrounding reefs, and whether the platforms act as fish enhancers (promoting recruitment) or only as aggregators. These questions are particularly relevant when the platforms are to be decommissioned and the possibility of allowing them to remain as artificial reefs is raised. This paper describes the results of the study on the fish populations around oil platforms and nearby natural reefs off Santa Barbara

  3. Design and skill assessment of an Operational Forecasting System for currents and sea level variability to the Santos Estuarine System - Brazil

    Science.gov (United States)

    Godoi Rezende Costa, C.; Castro, B. M.; Blumberg, A. F.; Leite, J. R. B., Sr.

    2017-12-01

    Santos City is subject to an average of 12 storm tide events per year. Such events bring coastal flooding able to threat human life and damage coastal infrastructure. Severe events have forced the interruption of ferry boat services and ship traffic through Santos Harbor, causing great impacts to Santos Port, the largest in South America, activities. Several studies have focused on the hydrodynamics of storm tide events but only a few of those studies have pursued an operational initiative to predict short term (operational forecasting system built to predict sea surface elevation and currents in the Santos Estuarine System and (ii) to evaluate model performance in simulating observed sea surface elevation. The Santos Operational Forecasting System (SOFS) hydrodynamic module is based on the Stevens Institute Estuarine and Coastal Ocean Model (sECOM). The fully automated SOFS is designed to provide up to 71 h forecast of sea surface elevations and currents every day. The system automatically collects results from global models to run the SOFS nested into another sECOM based model for the South Brazil Bight (SBB). Global forecasting results used to force both models come from Mercator Ocean, released by Copernicus Marine Service, and from the Brazilian developments on the Regional Atmospheric Modeling System (BRAMS) stablished by the Center for Weather Forecasts and Climate Studies (with Portuguese acronym CPTEC). The complete routines task take about 8 hours of run time to finish. SOFS was able to hindcast a severe storm tide event that took place in Santos on August 21-22, 2016. Comparisons with observed sea level provided skills of 0.92 and maximum root mean square errors of 25 cm. The good agreement with observed data shows the potential of the designed system to predict storm tides and to support both human and assets protection.

  4. Hot-spots of primary productivity: An Alternative interpretation to Conventional upwelling models

    Science.gov (United States)

    van Ruth, Paul D.; Ganf, George G.; Ward, Tim M.

    2010-12-01

    The eastern Great Australian Bight (EGAB) forms part of the Southern and Indian Oceans and is an area of high ecological and economic importance. Although it supports a commercial fishery, quantitative estimates of the primary productivity underlying this industry are open to debate. Estimates range from 500 mg C m -2 day -1. Part of this variation may be due to the unique upwelling circulation of shelf waters in summer/autumn (November-April), which shares some similarities with highly productive eastern boundary current upwelling systems, but differs due to the influence of a northern boundary current, the Flinders current, and a wide continental shelf. This study examines spatial variations in primary productivity in the EGAB during the upwelling seasons of 2005 and 2006. Daily integral productivity calculated using the vertically generalised production model (VGPM) showed a high degree of spatial variation. Productivity was low (modelled with the VGPM, which uses surface measures of phytoplankton biomass to calculate productivity. Macro-nutrient concentrations could not be used to explain the difference in the low and high productivities (silica > 1 μmol L -1, nitrate/nitrite > 0.4 μmol L -1, phosphate > 0.1 μmol L -1). Mixing patterns or micro-nutrient concentrations are possible explanations for spatial variations in primary productivity in the EGAB. On a global scale, daily rates of primary productivity of the EGAB lie between the highly productive eastern boundary current upwelling systems, and less productive coastal regions of western and south eastern Australia, and the oligotrophic ocean. However, daily productivity rates in the upwelling hotspots of the EGAB rival productivities in Benguela and Humboldt currents.

  5. Simulating oil droplet dispersal from the Deepwater Horizon spill with a Lagrangian approach

    Science.gov (United States)

    North, Elizabeth W.; Schlag, Zachary; Adams, E. Eric; Sherwood, Christopher R.; He, Ruoying; Hyun, Hoon; Socolofsky, Scott A.

    2011-01-01

    An analytical multiphase plume model, combined with time-varying flow and hydrographic fields generated by the 3-D South Atlantic Bight and Gulf of Mexico model (SABGOM) hydrodynamic model, were used as input to a Lagrangian transport model (LTRANS), to simulate transport of oil droplets dispersed at depth from the recent Deepwater Horizon MC 252 oil spill. The plume model predicts a stratification-dominated near field, in which small oil droplets detrain from the central plume containing faster rising large oil droplets and gas bubbles and become trapped by density stratification. Simulated intrusion (trap) heights of ∼ 310–370 m agree well with the midrange of conductivity-temperature-depth observations, though the simulated variation in trap height was lower than observed, presumably in part due to unresolved variability in source composition (percentage oil versus gas) and location (multiple leaks during first half of spill). Simulated droplet trajectories by the SABGOM-LTRANS modeling system showed that droplets with diameters between 10 and 50 μm formed a distinct subsurface plume, which was transported horizontally and remained in the subsurface for >1 month. In contrast, droplets with diameters ≥90 μm rose rapidly to the surface. Simulated trajectories of droplets ≤50 μm in diameter were found to be consistent with field observations of a southwest-tending subsurface plume in late June 2010 reported by Camilli et al. [2010]. Model results suggest that the subsurface plume looped around to the east, with potential subsurface oil transport to the northeast and southeast. Ongoing work is focusing on adding degradation processes to the model to constrain droplet dispersal.

  6. Composition and temporal patterns of larval fish communities in Chesapeake and Delaware Bays

    Directory of Open Access Journals (Sweden)

    Filipe Ribeiro

    2015-11-01

    Full Text Available Comparing larval fish assemblages in different estuaries provides insights about the coastal distribution of larval populations, larval transport, and adult spawning locations (Ribeiro et al. 2015. We simultaneously compared the larval fish assemblages entering two Middle Atlantic Bight (MAB estuaries (Delaware Bay and Chesapeake Bay, USA through weekly sampling from 2007 to 2009. In total, 43 taxa (32 families and 36 taxa (24 families were collected in Delaware and Chesapeake Bays, respectively. Mean taxonomic diversity, mean richness, and evenness were generally lower in Delaware Bay. Communities of both bays were dominated by Anchoa spp., Gobiosoma spp., Micropogonias undulatus, and Brevoortia tyrannus; Paralichthys spp. was more abundant in Delaware Bay and Microgobius thalassinus was more abundant in Chesapeake Bay. Inter-annual variation in the larval fish communities was low at both sites, with a relatively consistent composition across years, but strong seasonal (intra-annual variation in species composition occurred in both bays. Two groups were identified in Chesapeake Bay: a ‘winter’ group dominated by shelf-spawned species (e.g. M. undulatus and a ‘summer’ group comprising obligate estuarine species and coastal species (e.g. Gobiosoma spp. and Cynoscion regalis, respectively. In Delaware Bay, 4 groups were identified: a ‘summer’ group of mainly obligate estuarine fishes (e.g. Menidia sp. being replaced by a ‘fall’ group (e.g. Ctenogobius boleosoma and Gobionellus oceanicus; ‘winter’ and ‘spring’ groups were dominated by shelf-spawned (e.g. M. undulatus and Paralichthys spp. and obligate estuarine species (e.g. Leiostomus xanthurus and Pseudopleuronectes americanus, respectively. This study demonstrates that inexpensive and simultaneous sampling in different estuaries provides important insights into the variability in community structure of fish assemblages at large spatial scales.

  7. Rapid shelf‐wide cooling response of a stratified coastal ocean to hurricanes

    Science.gov (United States)

    Miles, Travis; Xu, Yi; Kohut, Josh; Schofield, Oscar; Glenn, Scott

    2017-01-01

    Abstract Large uncertainty in the predicted intensity of tropical cyclones (TCs) persists compared to the steadily improving skill in the predicted TC tracks. This intensity uncertainty has its most significant implications in the coastal zone, where TC impacts to populated shorelines are greatest. Recent studies have demonstrated that rapid ahead‐of‐eye‐center cooling of a stratified coastal ocean can have a significant impact on hurricane intensity forecasts. Using observation‐validated, high‐resolution ocean modeling, the stratified coastal ocean cooling processes observed in two U.S. Mid‐Atlantic hurricanes were investigated: Hurricane Irene (2011)—with an inshore Mid‐Atlantic Bight (MAB) track during the late summer stratified coastal ocean season—and Tropical Storm Barry (2007)—with an offshore track during early summer. For both storms, the critical ahead‐of‐eye‐center depth‐averaged force balance across the entire MAB shelf included an onshore wind stress balanced by an offshore pressure gradient. This resulted in onshore surface currents opposing offshore bottom currents that enhanced surface to bottom current shear and turbulent mixing across the thermocline, resulting in the rapid cooling of the surface layer ahead‐of‐eye‐center. Because the same baroclinic and mixing processes occurred for two storms on opposite ends of the track and seasonal stratification envelope, the response appears robust. It will be critical to forecast these processes and their implications for a wide range of future storms using realistic 3‐D coupled atmosphere‐ocean models to lower the uncertainty in predictions of TC intensities and impacts and enable coastal populations to better respond to increasing rapid intensification threats in an era of rising sea levels. PMID:28944132

  8. Potential Impacts of Offshore Wind Farms on North Sea Stratification

    Science.gov (United States)

    Carpenter, Jeffrey R.; Merckelbach, Lucas; Callies, Ulrich; Clark, Suzanna; Gaslikova, Lidia; Baschek, Burkard

    2016-01-01

    Advances in offshore wind farm (OWF) technology have recently led to their construction in coastal waters that are deep enough to be seasonally stratified. As tidal currents move past the OWF foundation structures they generate a turbulent wake that will contribute to a mixing of the stratified water column. In this study we show that the mixing generated in this way may have a significant impact on the large-scale stratification of the German Bight region of the North Sea. This region is chosen as the focus of this study since the planning of OWFs is particularly widespread. Using a combination of idealised modelling and in situ measurements, we provide order-of-magnitude estimates of two important time scales that are key to understanding the impacts of OWFs: (i) a mixing time scale, describing how long a complete mixing of the stratification takes, and (ii) an advective time scale, quantifying for how long a water parcel is expected to undergo enhanced wind farm mixing. The results are especially sensitive to both the drag coefficient and type of foundation structure, as well as the evolution of the pycnocline under enhanced mixing conditions—both of which are not well known. With these limitations in mind, the results show that OWFs could impact the large-scale stratification, but only when they occupy extensive shelf regions. They are expected to have very little impact on large-scale stratification at the current capacity in the North Sea, but the impact could be significant in future large-scale development scenarios. PMID:27513754

  9. A non-deltaic clinoform wedge fed by multiple sources off São Sebastião Island, southeastern Brazilian Shelf

    Science.gov (United States)

    Vieira, Ivo; Lobo, Francisco José; Montoya-Montes, Isabel; Siegle, Eduardo; Passos, Jorge Luiz; De Mahiques, Michel Michaelovitch

    2018-02-01

    São Sebastião Island (SSI) marks the latitudinal boundary between two sedimentological and geochemical provinces in the São Paulo Bight, an arc-shaped sector of the southeastern Brazilian Shelf. The island is separated from the continent by the narrow, deep São Sebastião Channel (SSC). A relatively thick sediment wedge—the São Sebastião Wedge (SSW)—has been formed offshore SSI. This study explores the possible genetic and evolutionary mechanisms of the wedge, bearing in mind that clinoform wedges can form at considerable distances from major fluvial sources. For that, a marine geological database has been interpreted comprising high-resolution seismic data, a surficial sediment map and several sediment cores, from which radiocarbon dates were obtained and sedimentation rates deduced. A wave model was also applied to obtain the dominant wave directions. The SSW is a wedge-shaped deposit, and its internal structure presents three seismic units. The two lowest are wedge shaped and arranged in a backstepping pattern. The most recent unit is mostly aggradational and can be divided into three seismic subunits. Sedimentological data show that at least the most recent unit is composed of a mixture of sands and silts. Modeled wave conditions indicate a major influence from southerly waves that are able to remobilize shelf sediments and to create a bypass sediment zone until the foreset of the deposit is reached at the water depths where the SSW is found. Taken together, these data suggest that the SSW formed through contributions from different sediment sources, and should be regarded as an intermediate case of a non-deltaic clinoform wedge. Sand transport in the area involves wind-driven currents passing through the SSC and sediment remobilization by energetic southerly waves. Fine-grained sediment is derived mostly from the joint contributions of many minor catchments located north of the island, and this sediment is later transported southwestward by the

  10. Satellite tracking of harbour seals on Horns Reef - Use of the Horns Reef wind farm area and the North Sea

    International Nuclear Information System (INIS)

    Tougaard, J.; Tougaard, S.; Jensen, Thyge; Ebbesen, I.; Teilmann, J.

    2003-03-01

    Ten harbour seals (Phoca vitulina) caught on the Danish Wadden Sea island Roemoe were equipped with satellite linked time depth recorders. The animals were caught on three separate occasions (Jan. 4th, Feb. 18th and May 6th, 2002). The transmitters worked between 49 and 100 days, relaying positional and dive information back via the ARGOS satellite service until beginning of July. Background for the studies is the construction of the Worlds largest off shore wind farm on Horns Reef. Based on previous studies using VHF-transmitters, it was expected that the seals would spend considerable time on Horns Reef. The VHF-telemetry studies showed that the preferred direction for seals leaving the Danish Wadden Sea is NW from Graedyb tidal area outside Esbjerg, the direction directly towards the wind farm area. The previously used VHF-transmitters had a limited detection range and it was decided to equip a number of seals from the same area as before with satellite transmitters. This allows for positioning of the seals in the entire North Sea as well as providing dive summary information, as a transmitter with a depth transducer was chosen for the study. Positional information revealed that animals move about more extensively than previously believed. Substantial variation between animals was observed and each seal seemed to have adopted its own foraging strategy. Some animals travelled to the centre of the North Sea on foraging trips and spent considerable time close to the bottom at 30-70 meters depth. Other seals remained in the German Bight and yet others spent considerable time on and around Horns Reef. The area of Horns reef wind farm constitutes a negligible fraction of the total area visited by the tagged seals. The reef as a whole however, appears to be important to the seals both for foraging and as transit area to other feeding grounds further off shore. The resolution in positional information is not sufficiently high to allow for a detailed study of the effects

  11. Evaluation of hydrodynamic ocean models as a first step in larval dispersal modelling

    Science.gov (United States)

    Vasile, Roxana; Hartmann, Klaas; Hobday, Alistair J.; Oliver, Eric; Tracey, Sean

    2018-01-01

    Larval dispersal modelling, a powerful tool in studying population connectivity and species distribution, requires accurate estimates of the ocean state, on a high-resolution grid in both space (e.g. 0.5-1 km horizontal grid) and time (e.g. hourly outputs), particularly of current velocities and water temperature. These estimates are usually provided by hydrodynamic models based on which larval trajectories and survival are computed. In this study we assessed the accuracy of two hydrodynamic models around Australia - Bluelink ReANalysis (BRAN) and Hybrid Coordinate Ocean Model (HYCOM) - through comparison with empirical data from the Australian National Moorings Network (ANMN). We evaluated the models' predictions of seawater parameters most relevant to larval dispersal - temperature, u and v velocities and current speed and direction - on the continental shelf where spawning and nursery areas for major fishery species are located. The performance of each model in estimating ocean parameters was found to depend on the parameter investigated and to vary from one geographical region to another. Both BRAN and HYCOM models systematically overestimated the mean water temperature, particularly in the top 140 m of water column, with over 2 °C bias at some of the mooring stations. HYCOM model was more accurate than BRAN for water temperature predictions in the Great Australian Bight and along the east coast of Australia. Skill scores between each model and the in situ observations showed lower accuracy in the models' predictions of u and v ocean current velocities compared to water temperature predictions. For both models, the lowest accuracy in predicting ocean current velocities, speed and direction was observed at 200 m depth. Low accuracy of both model predictions was also observed in the top 10 m of the water column. BRAN had more accurate predictions of both u and v velocities in the upper 50 m of water column at all mooring station locations. While HYCOM

  12. Small scale morphodynamics of shoreface-connected ridges and their impact on benthic macrofauna

    Science.gov (United States)

    Markert, Edith; Kröncke, Ingrid; Kubicki, Adam

    2015-05-01

    The first interdisciplinary analysis (biological and sedimentological) of macrofauna communities influenced by long-term morphodynamics of shoreface-connected ridges in the German Bight on a small scale is presented in this study. The study area covering 4 km2 was located off the island of Spiekeroog, in an area known as a Tellina fabula community. Sediment samples taken at 27 sample sites were coupled with side-scan sonar data to draw a precise sediment map of the area, as well as with high-resolution multi-beam bathymetry data to understand the morphodynamic changes of the seabed between 2003 and 2010. The macrofauna data acquired at the same 27 sites were analysed for community structure using non-metric multidimensional scaling, the ANOSIM and PERMANOVA tests. Correlations between biological and environmental variables were examined with the BIOENV procedure. The study revealed a shore-parallel sediment zonation with clear and sharp borders induced by local morphodynamics, which together with specific local bathymetry affected the formation of three different macrofauna affinity groups. One group was located on the shoreface and in the troughs (dominant species: Scoloplos armiger, Lanice conchilega, Notomastus latericeus), one on the landward flanks of the ridges (dominant species: Aonides paucibranchiata, Goniadella bobretzkii), and one on the ridge crests (dominant species: Ophelia spp. juv., Spio goniocephala). The spatial distribution of the affinity groups, their taxa number and abundance of species was dependent on a surface sediment pattern resulting from local hydrodynamics, which in turn is known to influence the food availability. A seaward steepening of ridges took place and was an effect of erosion up to 0.34 m on landward flanks in and accumulation up to 0.29 m on seaward flanks in seven years. The studied shoreface-connected ridges migrated seawards with a pace of 5 m/year for the large ridge and 20 m/year for the small ridge. Elongated mud

  13. Regionalization of climate model results for the North Sea

    Energy Technology Data Exchange (ETDEWEB)

    Kauker, F. [Alfred-Wegener-Institut fuer Polar- und Meeresforschung, Bremerhaven (Germany); Storch, H. von [GKSS-Forschungszentrum Geesthacht GmbH (Germany). Inst. fuer Hydrophysik

    2000-07-01

    A dynamical downscaling for the North Sea is presented. The numerical model used for the study is the coupled ice-ocean model OPYC. In a hindcast of the years 1979 to 1993 it was forced with atmospheric forcing of the ECMWF reanalysis. The models capability in simulating the observed mean state and variability in the North Sea is demonstrated by the hindcast. Two time scale ranges, from weekly to seasonal and the longer-than-seasonal time scales are investigated. Shorter time scales, for storm surges, are not captured by the model formulation. The main modes of variability of sea level, sea-surface circulation, sea-surface temperature, and sea-surface salinity are described and connections to atmospheric phenomena, like the NAO, are discussed. T106 ''time-slice'' simulations with a ''2 x CO{sub 2}'' horizon are used to estimate the effects of a changing climate on the shelf sea ''North Sea''. The ''2 x CO{sub 2}'' changes in the surface forcing are accompanied by changes in the lateral oceanic boundary conditions taken from a global coupled climate model. For ''2 x CO{sub 2}'' the time mean sea level increases up to 25 cm in the German Bight in the winter, where 15 cm are due to the surface forcing and 10 cm due to thermal expansion. This change is compared to the ''natural'' variability as simulated in the ECMWF integration and found to be not outside the range spanned by it. The variability of sea level on the weekly-to-seasonal time-scales is significantly reduced in the scenario integration. The variability on the longer-than-seasonal time-scales in the control and scenario runs is much smaller then in the ECMWF integration. This is traced back to the use of ''time-slice'' experiments. Discriminating between locally forced changes and changes induced at the lateral oceanic boundaries of the model in the circulation and

  14. The acclimative biogeochemical model of the southern North Sea

    Science.gov (United States)

    Kerimoglu, Onur; Hofmeister, Richard; Maerz, Joeran; Riethmüller, Rolf; Wirtz, Kai W.

    2017-10-01

    Ecosystem models often rely on heuristic descriptions of autotrophic growth that fail to reproduce various stationary and dynamic states of phytoplankton cellular composition observed in laboratory experiments. Here, we present the integration of an advanced phytoplankton growth model within a coupled three-dimensional physical-biogeochemical model and the application of the model system to the southern North Sea (SNS) defined on a relatively high resolution (˜ 1.5-4.5 km) curvilinear grid. The autotrophic growth model, recently introduced by Wirtz and Kerimoglu (2016), is based on a set of novel concepts for the allocation of internal resources and operation of cellular metabolism. The coupled model system consists of the General Estuarine Transport Model (GETM) as the hydrodynamical driver, a lower-trophic-level model and a simple sediment diagenesis model. We force the model system with realistic atmospheric and riverine fluxes, background turbidity caused by suspended particulate matter (SPM) and open ocean boundary conditions. For a simulation for the period 2000-2010, we show that the model system satisfactorily reproduces the physical and biogeochemical states of the system within the German Bight characterized by steep salinity; nutrient and chlorophyll (Chl) gradients, as inferred from comparisons against observation data from long-term monitoring stations; sparse in situ measurements; continuous transects; and satellites. The model also displays skill in capturing the formation of thin chlorophyll layers at the pycnocline, which is frequently observed within the stratified regions during summer. A sensitivity analysis reveals that the vertical distributions of phytoplankton concentrations estimated by the model can be qualitatively sensitive to the description of the light climate and dependence of sinking rates on the internal nutrient reserves. A non-acclimative (fixed-physiology) version of the model predicted entirely different vertical profiles

  15. Features of distribution and quality of organic matter in the bottom sediments of the Great Peter Bay (Sea of Japan)

    Science.gov (United States)

    Nesterova, Olga; Tregubova, Valentina; Semal, Victoria; Vasenev, Ivan

    2017-04-01

    The nature and distribution of organic carbon in marine waters depends on: 1) biological productivity and revenue of the autochthonous organic matter to the bottom; 2) sediment grain-size composition and conditions of dumping, which in turn depends of hydrothermic regime, topography, speed River mist and received major erosion products; 3) living conditions of the benthos (the quantity consumed of OM, gas regime of habitats, physiological capacity of heterotrophs). Autochthonous OM of phytoplankton plays a dominant role in the processes of formation of humus in aquatic conditions. Bottom sediments at different distance from the shoreline to depths from 0.5 up to 480 m of the Sea of Japan, which are formed in various conditions of facies, were selected as the objects of study. There is no clear relationships to the amount of organic matter in bottom sediments on the characteristics of the distribution and nature of living matter in the oceans and seas. This is because the process of sedimentation and fossilization of organic matter on the seabed and the ocean floor depends on many factors (currents, depth). Humus of studied bottom sediments in composition can be attributed mainly to the humic type. Nonhydrolyzing rest is 70-90%. This is characteristic of bottom sediments formed in facial types of small bays, internal coastal shelf bights and the underwater slope. At a fraction of the carbon of humic acids in organic matter, ranging from 4 to 80% of the amount of humic and fulvic acids. Fulvic acids content is much less. This is due to more favourable conservation situation of humic acids in precipitation with high content of organic matter, whereas fulvic acids in aquatic environments are more labile and almost not dumped. Despite the fact humic acids are not the most stable component (s), however, with increased content of humic acids, the mobility of organic matter and removing it from the bottom sediments are reduced. Internal shelf facies of the Great Peter Bay

  16. Evidence of natural reproduction of Atlantic sturgeon in the Connecticut River from unlikely sources.

    Directory of Open Access Journals (Sweden)

    Tom Savoy

    Full Text Available Atlantic Sturgeon is listed under the U.S. Endangered Species Act as five Distinct Population Segments (DPS. The "endangered" New York Bight (NYB DPS is thought to only harbor two populations; one in the Hudson River and a second smaller one in the Delaware River. Historically, the Connecticut River probably supported a spawning population of Atlantic Sturgeon that was believed extirpated many decades ago. In 2014, we successfully collected pre-migratory juvenile specimens from the lower Connecticut River which were subjected to mitochondrial DNA (mtDNA control region sequence and microsatellite analyses to determine their genetic relatedness to other populations coastwide. Haplotype and allelic frequencies differed significantly between the Connecticut River collection and all other populations coastwide. Sibship analyses of the microsatellite data indicated that the Connecticut River collection was comprised of a small number of families that were likely the offspring of a limited number of breeders. This was supported by analysis of effective population size (Ne and number of breeders (Nb. STRUCTURE analysis suggested that there were 11 genetic clusters among the coastwide collections and that from the Connecticut River was distinct from those in all other rivers. This was supported by UPGMA analyses of the microsatellite data. In AMOVA analyses, among region variation was maximized, and among population within regions variation minimized when the Connecticut River collection was separate from the other two populations in the NYB DPS indicating the dissimilarity between the Connecticut River collection and the other two populations in the NYB DPS. Use of mixed stock analysis indicated that the Connecticut River juvenile collection was comprised of specimens primarily of South Atlantic and Chesapeake Bay DPS origins. The most parsimonious explanation for these results is that the Connecticut River hosted successful natural reproduction in 2013

  17. La puerta del alma: el color de ojos y de cabello como forma discursiva de dominación (The doors of soul: the color hairs and eyes as a discursive instrument of domination

    Directory of Open Access Journals (Sweden)

    Korstanje, Maximiliano

    2010-06-01

    Full Text Available Resumen: El nacimiento de un hijo es un evento único e irremplazable para todos aquellos que han tenido la experiencia. Para otros, es una oportunidad de asenso social sobre todo sí por ese juego de los genes la criatura se asemeja al estereotipo indoeuropeo nórdico. Por ese motivo, los padres parecen interesados en que sus hijos tengan ojos claros y cabellos rubios tomando esa característica como cualitativamente positiva. Por ese motivo, no resulta extraño que las diferentes imágenes en publicidades de artículos para bebes enfatice en los “ojos azules y los cabellos rubios” como tipos ideales a seguir. La presente investigación ha demostrado que no sólo que los estereotipos dominantes se multiplican sino también se interiorizan generando un diálogo que tiende a reforzar la hegemonía. Por lo demás, se ha observado que discursivamente la claridad es simbolizada como sinónimo de felicidad, armonía, afecto, bondad y seguridad entre otros mientras la oscuridad adquiere categorías semánticas opuestas. Para los padres, que sus hijos tengan ojos “claros” o cabellos “rubios” significa un verdadero asenso social abstracto. Por lo pronto, no cobrarán un canon adicional por traer a la vida a un hijo rubio, pero los acerca notablemente más a las características de los grupos dominantes reforzando así el auto-desprecio por sí mismos.Abstract: Even a memorable moment as the birth of a son can be subject to a much broader pervasive experience. For some people, this event become in an opportunity to social upward wherein convergence genetic and eugenicist thoughts with concentration in Norse phenotype. For that reason, parents are concerned in their sons have bight eyes and blondes hairs. This is based on the postmodern advertising and marketing efforts to emphasize on these features. Under this context, this present research showed not only that dominant phenotypes are divulged thanks to the advertising but also create a

  18. Seasonal variations in production and consumption rates of dissolved organic carbon in an organic-rich coastal sediment

    Science.gov (United States)

    Alperin, M. J.; Albert, D. B.; Martens, C. S.

    1994-11-01

    Dissolved organic carbon (DOC) concentrations in anoxic marine sediments are controlled by at least three processes: (1) production of nonvolatile dissolved compounds, such as peptides and amino acids, soluble saccharides and fatty acids, via hydrolysis of particulate organic carbon (POC). (2) conversion of these compounds to volatile fatty acids and alcohols by fermentative bacteria. (3) consumption of volatile fatty acids and alcohols by terminal bacteria, such as sulfate reducers and methanogens. We monitored seasonal changes in concentration profiles of total DOC, nonacid-volatile (NAV) DOC and acid-volatile (AV) DOC in anoxic sediment from Cape Lookout Bight, North Carolina, USA, in order to investigate the factors that control seasonal variations in rates of hydrolysis, fermentation, and terminal metabolism. During the winter months, DOC concentrations increased continuously from 0.2 mM in the bottomwater to ~4 mM at a depth of 36 cm in the sediment column. During the summer, a large DOC maximum developed between 5 and 20 cm, with peak concentrations approaching 10 mM. The mid-depth summertime maximum was driven by increases in both NAV- and AV-DOC concentrations. Net NAV-DOC reaction rates were estimated by a diagenetic model applied to NAV-DOC concentration profiles. Depth-integrated production rates of NAV-DOC increased from February through July, suggesting that net rates of POC hydrolysis during this period are controlled by temperature. Net consumption of NAV-DOC during the late summer and early fall suggests reduced gross NAV-DOC production rates, presumably due to a decline in the availability of labile POC. A distinct subsurface peak in AV-DOC concentration developed during the late spring, when the sulfate depletion depth shoaled from 25 to 10 cm. We hypothesize that the AV-DOC maximum results from a decline in consumption by sulfate-reducing bacteria (due to sulfate limitation) and a lag in the development of an active population of methanogenic

  19. Satellite Remote Sensing Detection of Coastal Pollution in Southern California: Stormwater Runoff and Wastewater Plumes

    Science.gov (United States)

    Trinh, R. C.; Holt, B.; Gierach, M.

    2016-02-01

    Coastal pollution poses a major health and environmental hazard, not only for beach goers and coastal communities but for marine organisms as well. Stormwater runoff is the largest source of environmental pollution in coastal waters of the Southern California Bight (SCB) and is of great concern in increasingly urbanized areas. Buoyant wastewater plumes also pose a marine environmental risk. In this study we provide a comprehensive overview of satellite remote sensing capabilities in detecting buoyant coastal pollutants in the form of stormwater runoff and wastewater effluent. The SCB is the final destination of four major urban rivers that act as channels for runoff and pollution during and after rainstorms. We analyzed and compared sea surface roughness data from various Synthetic Aperture Radar (SAR) instruments to ocean color data from the Moderate Imaging System (MODIS) sensor on board the Aqua satellite and correlated the results with existing environmental data in order to create a climatology of naturally occurring stormwater plumes in coastal waters after rain events, from 1992 to 2014 from four major rivers in the area. Heat maps of the primary extent of stormwater plumes were constructed to specify areas that may be subject to the greatest risk of coastal contamination. In conjunction with our efforts to monitor coastal pollution and validate the abilities of satellite remote sensing, a recent Fall 2015 wastewater diversion from the City of Los Angeles Hyperion Treatment Plant (HTP) provided the opportunity to apply these remote sensing methodologies of plume detection to wastewater. During maintenance of their 5-mile long outfall pipe, wastewater is diverted to a shorter outfall pipe that terminates 1-mile offshore and in shallower waters. Sea surface temperature (SST), chlorophyll-a (chl-a) fluorescence, remote sensing reflectance and particulate backscatter signatures were analyzed from MODIS. Terra-ASTER and Landsat-8 thermal infrared data were also

  20. The nitrogen fate beyond the current nutrient mitigation measures: sustainability of an integrated agriculture

    Science.gov (United States)

    Thieu, V.; Billen, G. F.; Garnier, J.; Lancelot, C.; Gypens, N.

    2010-12-01

    Located in the North-Western Europe the terrestrial continuum that includes the Seine, Somme, and Scheldt River basins offers an interesting example of a transborder territory (France, Belgium, and Netherlands) with high-intensity anthropogenic pressures. It well-illustrates the rapid development of modern agriculture in industrialised countries and the resulting severe alteration of water resources and jeopardising the capacity of rural territories to produce drinking water. The corresponding nutrient loads delivered then into the Southern Bight of the North Sea, strongly affect the ecological functioning of the coastal zone. An integrated ‘river-ocean’ assessment, coupling two deterministic models - the SENEQUE RIVESTRAHLER model simulating nutrient dynamic in the drainage network and the MIRO model describing the ecological functioning coastal ecosystem - points out the relevance of current policy based measures (improvement of waste water treatment) to mitigate phosphorous emissions, while the nitrogen pollution related to agriculture will remain critical despite the implementation of classical management measure (good agricultural practices). Therefore and irrespectively of the current political agenda, a more radical alternative is established, consisting of a generalised shift to an integrated agriculture of all agricultural areas in the three basins, excluding the use of synthetically compounded fertilisers and the importation of livestock feed. Such scenario aims at evaluating whether agriculture, by essence, can conciliate (i) the demand for food and feed by local populations, (ii) a good ecological functioning of aquatic ecosystems and (iii) a balanced nutrient status for the adjacent coastal area. This scenario involves an increased livestock density in the Seine and Somme and a decrease in livestock in the Scheldt basin. It leads to a significant reduction of agricultural production that finally brings the three basins closer to autotrophy

  1. USGS analysis of the Australian UNCLOS submission

    Science.gov (United States)

    Hutchinson, Deborah R.; Rowland, Robert W.

    2006-01-01

    In November 2004, the Government of Australia made a submission to the Commission on the Limits of the Continental Shelf (CLCS) for 10 extended continental shelf (ECS) regions, utilizing Article-76 of the United Nations Convention on the Law of the Sea (UNCLOS). With information provided in the Australian Executive Summary, the USGS examined the 10 regions of the submission from geological, morphological, and resource perspectives. By their own request, the Australians asked that CLCS take no action on the Australian-Antarctic Territory. The major limitation in this analysis is that no bathymetric soundings or detailed hydrographic profiles were provided in the Australian Executive Summary that might show why the Foot of the Slope (FOS) was chosen or where the 2,500-m contour is located. This represents a major limitation because more than half of the 4,205 boundary points utilize the bathymetric formula line and more than one-third of them utilize the bathymetric constraint line. CLCS decisions on the components of this submission may set a precedent for how ECSs are treated in future submissions. Some of the key decisions will cover (a) how a 'natural prolongation' of a continental margin is determined, particularly if a bathymetric saddle that appears to determine the prolongation is in deep water and is well outside of the 200-nm limit (Exmouth Plateau), (b) defining to what extent that plateaus, rises, caps, banks and spurs that are formed of oceanic crust and from oceanic processes can be considered to be 'natural prolongations' (Kerguelen Plateau), (c) to what degree UNCLOS recognizes reefs and uninhabited micro-islands (specifically, rocks and/or sand shoals) as islands that can have an EEZ (Middleton and Elizabeth Reefs north of Lord Howe Island), and (d) how the Foot of the Slope (FOS) is chosen (Great Australian Bight). The submission contains situations that are relevant to potential future U.S. submissions and are potentially analogous to certain

  2. Produção primária e algumas considerações ecológicas da região de Ubatuba (Lat. 23º30's - Long. 45º06'w, Brasil Primary production and some ecological considerations from Ubatuba region (Lat. 23º30'S - Long. 45º06'W, Brazil

    Directory of Open Access Journals (Sweden)

    Clóvis Teixeira

    1979-01-01

    Full Text Available Medidas sobre produção primária, foram determinadas em trés diferentes pontos de uma enseada (Lat. 23º30'S; Long. 45º06'W durante o inverno e verão (1975-1976 . Algumas características fotossintéticas das populações naturais foram determinadas em condições simuladas. Os valores da produção primaria, relacionados às condições ambientais e aos diferentes valores C:clorofila-a encontrados, demonstraram que a região estudada apresenta características oligotroficas . A composição do fitoplâncton, com relaçao ao seu tamanho celular, deve, entretanto, favorecer um aproveitamento máximo dos nutrientes em termos de assimilação e propiciar uma elevada taxa de multiplicação celular. Os altos valores encontrados para os diferentes demonstraram que as populações estudadas sao adaptadas às altas intensidades luminosas, desde que nenhuma barreira física seja estabelecida. Além das considerações ecologicas apresentadas, os dados obtidos permitiram sugerir uma possível viabilidade da criação de organismos filtradores como uma opção para a maricultura.Primary production and hydrographic measurements were taken at three different points at a bight (Lat. 23º30'S; Long. 45º06'W during the winter and summer (1975-76. Some photosynthetic characteristics of the natural populations were also simulated in laboratory experiments. The relation between primary production and the environmental parameters, as well as with the different values of C: chlorophyll obtained, showed that the region is oligotrophic. However the cell size composition of phytoplarikton may promove a maximum uptake of nutrients and improve the cellular reproduction. High values found for Ik showed that the population is adapted to high intensities as long as no physical barrier is established. Besides the ecological aspects presented the results allow us to suggest the viability of growing filter-feeding organisms as an option for marine culture.

  3. Overflow Water Pathways in the Subpolar North Atlantic Observed with Deep Floats

    Science.gov (United States)

    Bower, Amy; Furey, Heather; Lozier, Susan

    2017-04-01

    As part of the Overturning in the Subpolar North Atlantic Program (OSNAP), a total of 135 acoustically tracked RAFOS floats have been deployed in the deep boundary currents of the Iceland, Irminger and Labrador Basins, and in the Charlie-Gibbs Fracture Zone, to investigate the pathways of Iceland-Scotland Overflow Water (ISOW) and Denmark Strait Overflow Water (DSOW). Floats were released annually in 2014, 2015 and 2016 at depths between 1800 and 2800 m for two-year missions. The array of sound sources used for tracking was expanded from 10 to 13 moorings in 2016 when it was discovered that wintertime surface roughness was negatively impacting acoustic ranges. The floats from the first setting reveal several examples of persistent , deep coherent eddy motion, including a cyclonic eddy spinning off the tip of Eirik Ridge (southwest of Cape Farewell), a cyclonic eddy in the northeastern Labrador Basin near where anticyclonic Irminger Rings are formed, and an anticyclonic eddy under the North Atlantic Current (NAC) in the central Iceland Basin. A consistent region of boundary-interior exchange was observed near Hamilton Bank on the western boundary of the Labrador Sea. Deep cyclonic recirculation gyres are revealed in all three basins. Floats released in the southward-flowing deep boundary current over the eastern flank of the Reykjanes Ridge show that shallower layers of ISOW peel off to the west and cross the Ridge into the Irminger Basin through various gaps south of 60°N, including the Bight Fracture Zone. These floats tend to turn northward and continue along the slope in the Irminger Basin. Interestingly, floats released at the ISOW level in the CGFZ did not turn into the Irminger Basin as often depicted in deep circulation schematics, but rather drifted west-northwestward toward the Labrador Sea, or eddied around west of the CGFZ and (in some cases) turned southward. This result is consistent with some previous hydrographic and high-resolution model results

  4. Xenoestrogens in the River Elbe and its tributaries

    International Nuclear Information System (INIS)

    Stachel, Burkhard; Ehrhorn, Ute; Heemken, Olaf-Peter; Lepom, Peter; Reincke, Heinrich; Sawal, Georg; Theobald, Norbert

    2003-01-01

    High concentrations of organic chemicals in the River Elbe may be detrimental to aquatic organisms. - 4-Alkylphenols, 4-alkylphenol ethoxylates, 4-alkylphenoxy carboxylates, bisphenol A, bisphenol F, 4-hydroxyacetophenon, 4-hydroxybenzoic acid and steroid hormones were analyzed in water samples of the River Elbe and its tributaries Schwarze Elster, Mulde, Saale, Havel and Schwinge. Additionally, freshly deposited sediments (FDS, composite samples) of the River Elbe and its tributaries were analyzed. The concentrations in water samples ranged from (in ng/l): bisphenol A 4 to 92, branched nonylphenol 13 to 87, branched nonylphenol ethoxylates <0.5 to 120, 4-tert. nonylphenoxy carboxylates <10 to 940 and 4-hydroxybenzoic acid 4 to 12. Steroid hormones were only detected in the Czech tributaries Jizera and Vltava in concentrations near the limit of quantification. In FDS samples the concentrations amounted to (in μg/kg d.w.): bisphenol A 10-380, branched nonylphenol 27-430, branched nonylphenol ethoxylates 24-3700, nonylphenoxy carboxylates <50 and 4-hydroxybenzoic acid 23-4400. Increased bisphenol A concentrations were found in water and FDS samples taken from the Czech-German border at Schmilka and the mouth of the Schwinge (only water sample). According to studies conducted in the Elbe Estuary and the German Bight, the River Elbe must be considered as a major source of pollution for the North Sea in respect of the compounds analyzed. A comparison of bisphenol A concentrations, 4-alkylphenols and the corresponding ethoxylates analyzed in the River Elbe and its tributaries with those found in other German surface waters indicated a low level of contamination. The evaluation of the data based on LOEC-values indicated that the concentrations were well below the effectivity threshold for some 4-alkylphenols. According to recent ecotoxicological investigations, for example, with prosobranch snails, bisphenol A concentrations found in water samples of the River Elbe and

  5. Salt Marsh Formation in the Lower Hudson River Estuary

    Science.gov (United States)

    Merley, Michael; Peteet, Dorothy; Hansen, James E. (Technical Monitor)

    2001-01-01

    Salt marshes are constant depositional environments and as a result contain accurate indicators of past relative sea level rise and salinity. The Hudson River marshes are at least twice as deep when compared to coastal marshes on either side of the mouth of the Hudson. The reason for this difference in sedimentation is unclear. This study uses macrofossil data as well as sediment stratigraphy in order to understand the formation and evolution of these marshes. The composition of seeds, roots, shoots and foraminifera, are used to indicate past sea levels. The four sites involved in this study are, from south to north, the Arthur Kill Marsh in Staten Island (40 36 N, 74 77W), Piermont marsh (N 4100; 73 55W) Croton Point (41 14 N; 73 50W) and Iona Island (41 18N, 73 58W). These are all tidally influenced but with increasing distances from the New York Bight, which gives a good spectrum of tidal influence. AMS-C14 dates on basal macrofossils will document the time of each marsh formation. Basal material from Arthur Kill (8 m) includes freshwater seeds such as Viola, Potomageton and Alnus along with Salix buds. Basal material from Croton Point (10 m) includes fibrous woody material, foraminifera and Zanichellia seeds and other brackish vegetational components. The basal material from Piermont (13.77 m) is lacking any identifiable macrofossils between 150 and 500 microns. The basal material from Iona Island (10 m) has vegetation such as Scirpus and Cyperus seeds, probably implying a brackish environment. The freshwater origin of the Arthur Kill marsh in Staten Island is significant because it predates either sea level rise or the western channel incision. Additional implications for this study include evidence for changes in river channel geomorphology. Reasons for the relatively deeper river marshes include possible basal clay compaction, high production due to river and marine nutrients as well as tectonic activity. This study provides the groundwork for more high

  6. Vertical suspsended sediment fluxes observed from ocean gliders

    Science.gov (United States)

    Merckelbach, Lucas; Carpenter, Jeffrey

    2016-04-01

    Many studies trying to understand a coastal system in terms of sediment transport paths resort to numerical modelling - combining circulation models with sediment transport models. Two aspects herein are crucial: sediment fluxes across the sea bed-water column interface, and the subsequent vertical mixing by turbulence. Both aspects are highly complex and have relatively short time scales, so that the processes involved are implemented in numerical models as parameterisations. Due to the effort required to obtain field observations of suspended sediment concentrations (and other parameters), measurements are scarce, which makes the development and tuning of parameterisations a difficult task. Ocean gliders (autonomous underwater vehicles propelled by a buoyancy engine) provide a platform complementing more traditional methods of sampling. In this work we present observations of suspended sediment concentration (SSC) and dissipation rate taken by two gliders, each equipped with optical sensors and a microstructure sensor, along with current observations from a bottom mounted ADCP, all operated in the German Bight sector of the North Sea in Summer 2014. For about two weeks of a four-week experiment, the gliders were programmed to fly in a novel way as Lagrangian profilers to water depths of about 40 m. The benefit of this approach is that the rate of change of SSC - and other parameters - is local to the water column, as opposed to an unknown composition of temporal and spatial variability when gliders are operated in the usual way. Therefore, vertical sediment fluxes can be calculated without the need of the - often dubious - assumption that spatial variability can be neglected. During the experiment the water column was initially thermally stratified, with a cross-pycnocline diffusion coefficient estimated at 7\\cdot10-5 m2 s-1. Halfway through the experiment the remnants of tropical storm Bertha arrived at the study site and caused a complete mixing of the water

  7. Covariation of viral parameters with bacterial assemblage richness and diversity in the water column and sediments

    Science.gov (United States)

    Hewson, Ian; Fuhrman, Jed A.

    2007-05-01

    Viruses are hypothesized to maintain diversity in microbial assemblages by regulating the abundance of dominant competitors and thereby allowing less-dominant competitors to persist in assemblages; however, there have been few empirical data sets to support this idea. In this study, we examined the relationship between the ratio of viral abundance to bacterial abundance, viral production, and the relative richness and diversity of bacterial assemblage fingerprints, in samples taken from geographically widespread locations (North Pacific gyre, the Amazon River plume and adjacent North Atlantic gyre, Gulf of Mexico, Southern California Bight and Arafura—Coral Seas) which are oligo- to mesotrophic. Bacterial assemblage richness and diversity as measured by automated rRNA intergenic spacer (ARISA) fingerprinting were significantly and positively correlated with the ratio of virus abundance to bacteria abundance (VBR) and to the rate of virus production only in the oligotrophic North Pacific gyre. ARISA fingerprint richness/diversity were not significantly correlated to viral parameters when assessed across all samples in surface waters, suggesting there is not a singular global quantitative relationship between viral pressure and host diversity within well evolved host/virus systems in different geographic locations in plankton. In sediments off Southern California, viral parameters significantly and negatively correlated with ARISA diversity, suggesting strong viral interactions in this habitat. To examine covariation of viral parameters and the relative abundance and diversity of rarer bacterial taxa (i.e., less-dominant competitor), the richness and diversity of diazotroph communities was measured using terminal restriction fragment length polymorphism (TRFLP) of a portion ( nifH) of the nitrogenase gene. The richness and diversity of diazotrophic communities were significantly and negatively correlated with viral parameters across all locations. Since diazotrophs

  8. The Southern California Coastal Ocean Observing System (SCCOOS): Developing A Coastal Observation System To Enable Both Science Based Decision Making And Scientific Discovery

    Science.gov (United States)

    Terrill, E.; John, O.

    2005-05-01

    The Southern California Coastal Ocean Observing System (SCCOOS) is a consortium that extends from Northern Baja CA in Mexico to Morro Bay at the southern edge of central California, and aims to streamline, coordinate, and further develop individual institutional efforts by creating an integrated, multidisciplinary coastal observatory in the Bight of Southern California for the benefit of society. By leveraging existing infrastructure, partnerships, and private, local, state, and federal resources, SCCOOS is developing a fully operational coastal observation system to address issues related to coastal water quality, marine life resources, and coastal hazards for end user communities spanning local, state, and federal interests. However, to establish a sensible observational approach to address these societal drivers, sound scientific approaches are required in both the system design and the transformation of data to useful products. Since IOOS and coastal components of the NSF Ocean Observatories Initiative (OOI) are not mutually exclusive within this framework, the SCCOOS consortium of observatory implementers have created an organizational structure that encourages dovetailing of OOI into the routine observations provided by the operational components of a regional IOOS. To begin the development, SCCOOS has grant funding from the California Coastal Conservancy as part of a $21M, statewide initiative to establish a Coastal Ocean Currents Monitoring Program, and funding from NOAA's Coastal Observing Technology System (COTS). In addition, SCCOOS is leveraging IT development that has been supported by the NSF Information Technology Research program Real-time observatories, Applications,and Data Manageemnt Network (ROADNET), and anticipates using developments which will result from the NSF Laboratory for Ocean Observatory Knowledge Integration Grid (LOOKING) program. The observational components now funded at SCCOOS include surface current mapping by HF radar; high

  9. Satellite tracking of harbour seals on Horns Reef - Use of the Horns Reef wind farm area and the North Sea

    Energy Technology Data Exchange (ETDEWEB)

    Tougaard, J.; Tougaard, S.; Jensen, Thyge [Fisheries and Maritime Museum Esbjerg (Denmark); Ebbesen, I. [Univ. of Sourthern Denmark, Inst. of Biology, Odense (Denmark); Teilmann, J. [NationL Environmental Res. Inst., Roskidle (Denmark)

    2003-03-15

    Ten harbour seals (Phoca vitulina) caught on the Danish Wadden Sea island Roemoe were equipped with satellite linked time depth recorders. The animals were caught on three separate occasions (Jan. 4th, Feb. 18th and May 6th, 2002). The transmitters worked between 49 and 100 days, relaying positional and dive information back via the ARGOS satellite service until beginning of July. Background for the studies is the construction of the Worlds largest off shore wind farm on Horns Reef. Based on previous studies using VHF-transmitters, it was expected that the seals would spend considerable time on Horns Reef. The VHF-telemetry studies showed that the preferred direction for seals leaving the Danish Wadden Sea is NW from Graedyb tidal area outside Esbjerg, the direction directly towards the wind farm area. The previously used VHF-transmitters had a limited detection range and it was decided to equip a number of seals from the same area as before with satellite transmitters. This allows for positioning of the seals in the entire North Sea as well as providing dive summary information, as a transmitter with a depth transducer was chosen for the study. Positional information revealed that animals move about more extensively than previously believed. Substantial variation between animals was observed and each seal seemed to have adopted its own foraging strategy. Some animals travelled to the centre of the North Sea on foraging trips and spent considerable time close to the bottom at 30-70 meters depth. Other seals remained in the German Bight and yet others spent considerable time on and around Horns Reef. The area of Horns reef wind farm constitutes a negligible fraction of the total area visited by the tagged seals. The reef as a whole however, appears to be important to the seals both for foraging and as transit area to other feeding grounds further off shore. The resolution in positional information is not sufficiently high to allow for a detailed study of the effects

  10. An Automated Approach to Reasoning Under Multiple Perspectives

    Science.gov (United States)

    deBessonet, Cary

    2004-01-01

    This is the final report with emphasis on research during the last term. The context for the research has been the development of an automated reasoning technology for use in SMS (symbolic Manipulation System), a system used to build and query knowledge bases (KBs) using a special knowledge representation language SL (Symbolic Language). SMS interpreters assertive SL input and enters the results as components of its universe. The system operates in two basic models: 1) constructive mode (for building KBs); and 2) query/search mode (for querying KBs). Query satisfaction consists of matching query components with KB components. The system allows "penumbral matches," that is, matches that do not exactly meet the specifications of the query, but which are deemed relevant for the conversational context. If the user wants to know whether SMS has information that holds, say, for "any chow," the scope of relevancy might be set so that the system would respond based on a finding that it has information that holds for "most dogs," although this is not exactly what was called for by the query. The response would be qualified accordingly, as would normally be the case in ordinary human conversation. The general goal of the research was to develop an approach by which assertive content could be interpreted from multiple perspectives so that reasoning operations could be successfully conducted over the results. The interpretation of an SL statement such as, "{person believes [captain (asserted (perhaps)) (astronaut saw (comet (bright)))]}," which in English would amount to asserting something to the effect that, "Some person believes that a captain perhaps asserted that an astronaut saw a bright comet," would require the recognition of multiple perspectives, including some that are: a) epistemically-based (focusing on "believes"); b) assertion-based (focusing on "asserted"); c) perception-based (focusing on "saw"); d) adjectivally-based (focusing on "bight"); and e) modally

  11. Drivers of Intra-Summer Seasonality and Daily Variability of Coastal Low Cloudiness in California Subregions

    Science.gov (United States)

    Schwartz, R. E.; Iacobellis, S.; Gershunov, A.; Williams, P.; Cayan, D. R.

    2014-12-01

    Summertime low cloud intrusion into the terrestrial west coast of North America impacts human, ecological, and logistical systems. Over a broad region of the West Coast, summer (May - September) coastal low cloudiness (CLC) varies coherently on interannual to interdecadal timescales and has been found to be organized by North Pacific sea surface temperature. Broad-scale studies of low stratiform cloudiness over ocean basins also find that the season of maximum low stratus corresponds to the season of maximum lower tropospheric stability (LTS) or estimated inversion strength. We utilize a 18-summer record of CLC derived from NASA/NOAA Geostationary Operational Environmental Satellite (GOES) at 4km resolution over California (CA) to make a more nuanced spatial and temporal examination of intra-summer variability in CLC and its drivers. We find that uniform spatial coherency over CA is not apparent for intra-summer variability in CLC. On monthly to daily timescales, at least two distinct subregions of coastal California (CA) can be identified, where relationships between meteorology and stratus variability appear to change throughout summer in each subregion. While north of Point Conception and offshore the timing of maximum CLC is closely coincident with maximum LTS, in the Southern CA Bight and northern Baja region, maximum CLC occurs up to about a month before maximum LTS. It appears that summertime CLC in this southern region is not as strongly related as in the northern region to LTS. In particular, although the relationship is strong in May and June, starting in July the daily relationship between LTS and CLC in the south begins to deteriorate. Preliminary results indicate a moderate association between decreased CLC in the south and increased precipitable water content above 850 hPa on daily time scales beginning in July. Relationships between daily CLC variability and meteorological variables including winds, inland temperatures, relative humidity, and

  12. Coupling alongshore variations in wave energy to beach morphologic change using the SWAN wave model at Ocean Beach, San Francisco, CA

    Science.gov (United States)

    Eshleman, Jodi L.; Barnard, Patrick L.; Erikson, Li H.; Hanes, Daniel M.

    2007-01-01

    conditions to help isolate the effects of offshore wave direction and period on nearshore wave predictions. Alongshore varying average beach change statistics are computed at specific profile locations from topographic beach surveys and lidar data. The study area is located in the San Francisco Bight in central California. Ocean Beach is a seven kilometer long north-south trending sandy coastline located just south of the entrance to the San Francisco Bay Estuary (Figure 1). It contains an erosion hotspot in the southern part of the beach which has resulted in damage to local infrastructure and is the cause of continued concern. A wide range of field data collection and numerical modeling efforts have been focused here as part of the United States Geological Survey's (USGS) San Francisco Bight Coastal Processes Study, which began in October 2003 and represents the first comprehensive study of coastal processes at the mouth of San Francisco Bay. Ocean Beach is exposed to very strong tidal flows, with measured currents often in excess of 1 m/s at the north end of the beach. Current profiler measurements indicate that current magnitudes are greater in the northern portion of the beach, while wave energy is greater in the southern portion where erosion problems are greatest (Barnard et al., 2007). The sub-aerial beach volume fluctuates seasonally over a maximum envelope of 400,000 m3 for the seven kilometer stretch (Barnard et al, 2007). The wave climate in the region is dominated by an abundance of low frequency energy (greater than 20 s period) and prevailing northwest incident wave angles. The application of a wave model to the region is further complicated by the presence of the Farallon Islands 40 kilometers west, and a massive ebb tidal delta at the mouth of San Francisco Bay (~150 km2), which creates complicated refraction patterns as wave energy moves from offshore Ocean Beach; however the cost and threat of the energetic nearshore environment have limited the temporal

  13. Surficial sediment character of the New York-New Jersey offshore continental shelf region: a GIS compilation

    Science.gov (United States)

    Williams, S. Jeffress; Arsenault, Matthew A.; Poppe, Lawrence J.; Reid, Jane A.; Reid, Jamey M.; Jenkins, Chris J.

    2007-01-01

    Broad continental shelf regions such as the New York Bight are the product of a complex geologic history and dynamic oceanographic processes, dominated by the Holocene marine transgression (>100 m sea-level rise) following the end of the last Pleistocene ice advance ~ 20,000 years ago. The area of the U.S. Exclusive Economic Zone (U.S. EEZ) territory, extending 200 nautical miles seaward from the coast, is larger than the continental U.S. and contains submerged landforms that provide a variety of natural functions and societal benefits, such as: critical habitats for fisheries, ship navigation and homeland security, and engineering activities (i.e. oil and gas platforms, pipeline and cable routes, potential wind-energy-generation sites). Some parts of the continental margins, particularly inner-continental shelf regions, also contain unconsolidated hard-mineral deposits such as sand and gravel that are regarded as potential aggregate resources to meet or augment needs not met by onshore deposits (Williams, 1992). The present distribution of surficial sediment off the northeastern United States is shaped from the deposits left by the last glaciation and reflects the cumulative effects of sediment erosion, transport, sorting, and deposition by storm and tidal processes during the Holocene rise in sea level. As a result, the sediments on the sea floor represent both an historical record of former conditions and a guide to possible future sedimentary environments. The U.S. Geological Survey (USGS) through the Coastal and Marine Geology Program, in cooperation with the University of Colorado and other partners, has compiled extant sediment character and textural data as well as other geologic information on the sea floor from all regions around the U.S. into the usSEABED data system (Reid and others, 2005; Buczkowski and others, 2006; Reid and others, 2006). The usSEABED system, which contains information on sediment grain size and lithology for more than 340

  14. Fluvial fluxes of natural radium isotopes and dissolved barium for Ubatuba embayments, Sao Paulo

    International Nuclear Information System (INIS)

    Sousa, Keila Cristina Pinheiro Marchini de

    2008-01-01

    Radium isotopes are among the most important isotopes in the environment from both radioprotection and geo-hydrological points of view. They are also a powerful tool for studying geohydrological processes and have been used intensively as tracers of groundwater sources that discharge into the coastal ocean.The complex exchange of fluvial, subsurface and seawater within a coastal area directly affects global biogeochemical cycles. Environmental scientists have few tools to accurately quantify such processes and must therefore rely on various tracer techniques. Radium isotopes have been frequently applied as tracers of submarine groundwater discharge (SGD). The unique radium signature of SGD is acquired within the subterranean estuary, a mixing zone between fresh groundwater and seawater in coastal aquifers. In this study we determined the fluvial fluxes of the radium isotopes and dissolved barium for Ubatuba embayments, northernmost part of Sao Paulo Bight. The research work was carried out from April/ 2007 to August/ 2007 and covered 17 small rivers sources that belong to the major surface draining system of such coastal area. During this period of investigation, groundwater samples were also collected from 10 sources available in this coastal region. Activity concentrations of 223 Ra in riverine waters discharging to Ubatuba and Caraguatatuba embayments varied from -1 to 335 mBq 1000L -1 (in Cocanha River), while 224 Ra concentrations ranged from 17 mBq 100L -1 to 7270 mBq 100L -1 . Activity concentrations up to 1424 mBq 100L -1 were observed for 226 Ra in riverine waters, while 228 Ra concentrations varied from 1412 mBq 100L -1 to 4058 mBq 100L -1 . Groundwater activity concentrations of 223 Ra varied from 1 mBq 100L -1 to 126 mBq 100L -1 , while 224 Ra ranged from 118 mBq 100L -1 to 3701 mBq 100L -1 . 223 Ra/ 224 Ra activity ratios up to 0.7x10 -1 and 0.2 were observed in riverine and groundwater, respectively. For 226 Ra groundwater activity concentrations

  15. Atmospheric Wind Relaxations and the Oceanic Response in the California Current Large Marine Ecosystem

    Science.gov (United States)

    Fewings, M. R.; Dorman, C. E.; Washburn, L.; Liu, W.

    2010-12-01

    On the West Coast of North America in summer, episodic relaxation of the upwelling-favorable winds causes warm water to propagate northward from southern to central California, against the prevailing currents [Harms and Winant 1998, Winant et al. 2003, Melton et al. 2009]. Similar wind relaxations are an important characteristic of coastal upwelling ecosystems worldwide. Although these wind relaxations have an important influence on coastal ocean dynamics, no description exists of the regional atmospheric patterns that lead to wind relaxations in southern California, or of the regional ocean response. We use QuikSCAT wind stress, North American Regional Reanalysis atmospheric pressure products, water temperature and velocity from coastal ocean moorings, surface ocean currents from high-frequency radars, and MODIS satellite sea-surface temperature and ocean color images to analyze wind relaxation events and the ocean response. We identify the events based on an empirical index calculated from NDBC buoy winds [Melton et al. 2009]. We describe the regional evolution of the atmosphere from the Gulf of Alaska to Baja California over the few days leading up to wind relaxations, and the coastal ocean temperature, color, and current response off southern and central California. We analyze ~100 wind relaxation events in June-September during the QuikSCAT mission, 1999-2009. Our results indicate south-central California wind relaxations in summer are tied to mid-level atmospheric low-pressure systems that form in the Gulf of Alaska and propagate southeastward over 3-5 days. As the low-pressure systems reach southern California, the atmospheric pressure gradient along the coast weakens, causing the surface wind stress to relax to near zero. The weak wind signal appears first at San Diego and propagates northward. QuikSCAT data indicate the relaxed winds extend over the entire Southern California Bight and up to 200 km offshore of central California. Atmospheric dynamics in

  16. Estimating Population Turnover Rates by Relative Quantification Methods Reveals Microbial Dynamics in Marine Sediment.

    Science.gov (United States)

    Kevorkian, Richard; Bird, Jordan T; Shumaker, Alexander; Lloyd, Karen G

    2018-01-01

    The difficulty involved in quantifying biogeochemically significant microbes in marine sediments limits our ability to assess interspecific interactions, population turnover times, and niches of uncultured taxa. We incubated surface sediments from Cape Lookout Bight, North Carolina, USA, anoxically at 21°C for 122 days. Sulfate decreased until day 68, after which methane increased, with hydrogen concentrations consistent with the predicted values of an electron donor exerting thermodynamic control. We measured turnover times using two relative quantification methods, quantitative PCR (qPCR) and the product of 16S gene read abundance and total cell abundance (FRAxC, which stands for "fraction of read abundance times cells"), to estimate the population turnover rates of uncultured clades. Most 16S rRNA reads were from deeply branching uncultured groups, and ∼98% of 16S rRNA genes did not abruptly shift in relative abundance when sulfate reduction gave way to methanogenesis. Uncultured Methanomicrobiales and Methanosarcinales increased at the onset of methanogenesis with population turnover times estimated from qPCR at 9.7 ± 3.9 and 12.6 ± 4.1 days, respectively. These were consistent with FRAxC turnover times of 9.4 ± 5.8 and 9.2 ± 3.5 days, respectively. Uncultured Syntrophaceae , which are possibly fermentative syntrophs of methanogens, and uncultured Kazan-3A-21 archaea also increased at the onset of methanogenesis, with FRAxC turnover times of 14.7 ± 6.9 and 10.6 ± 3.6 days. Kazan-3A-21 may therefore either perform methanogenesis or form a fermentative syntrophy with methanogens. Three genera of sulfate-reducing bacteria, Desulfovibrio , Desulfobacter , and Desulfobacterium , increased in the first 19 days before declining rapidly during sulfate reduction. We conclude that population turnover times on the order of days can be measured robustly in organic-rich marine sediment, and the transition from sulfate-reducing to methanogenic conditions stimulates

  17. Extreme 13Ccarb enrichment in ca. 2.0 Ga magnesite-stromatolite-dolomite-`red beds' association in a global context: a case for the world-wide signal enhanced by a local environment

    Science.gov (United States)

    Melezhik, Victor A.; Fallick, Anthony E.; Medvedev, Pavel V.; Makarikhin, Vladimir V.

    1999-12-01

    The Palaeoproterozoic positive excursion of δ 13Ccarb is now considered as three positive shifts of δ 13Ccarb separated by returns to 0‰, which all occurred between 2.40 and 2.06 Ma. This isotopic event is unique in terms of both duration (>300 Ma) and 13C enrichment (up to +18‰). The mechanism responsible for one of the most significant carbon isotopic shifts in Earth history remains highly debatable. To date, δ 13C of +10‰ to +15‰ cannot be balanced by organic carbon burial ( forg) as there is no geological evidence for an enhanced C org accumulation prior to or synchronous with the excursion. Instead, termination of these excursions is followed by formation of a vast reservoir of 13C-depleted organic material (-45‰ at Shunga) and by one of the earliest known oil-generation episodes at 2.0 Ga. None of the three positive excursions of δ 13Ccarb is followed by a negative isotopic shift significantly below 0‰, as has always been observed in younger isotopic events, reflecting an overturn of a major marine carbon reservoirs. This may indicate that forg was constant: implying that the mechanism involved in the production of C org was different. Onset of intensive methane cycling resulting in Δc change is another possibility. The majority of sampled 13Ccarb-rich localities represents shallow-water stromatolitic dolostones, `red beds' and evaporites formed in restricted intracratonic basins, and may not reflect global δ 13Ccarb values. Closely spaced drill core samples ( n=73) of stromatolitic dolostones from the >1980±27 Ma Tulomozerskaya Formation in the Onega palaeobasin, Russian Karelia, have been analysed for δ 13Ccarb and δ 18Ocarb in order to demonstrate that different processes were involved in the formation of 13Ccarb-rich carbonates. The 800 m-thick magnesite-stromatolite-dolomite-`red beds' succession formed in a complex combination of environments on the Karelian craton: peritidal shallow marine, low-energy protected bights, barred

  18. Variability of Wind Speeds and Power over Europe

    Science.gov (United States)

    Tambke, J.; von Bremen, L.; de Decker, J.; Schmidt, M.; Steinfeld, G.; Wolff, J.-O.

    2010-09-01

    This study comprises two parts: First, we describe the vertical wind speed and turbulence profiles that result from our improved PBL scheme and compare it to observations and 1-dimensional approaches (Monin-Obukhov etc.). Second, we analyse the spatio-temporal correlations in our meso-scale simulations for the years 2004 to 2007 over entire Europe, with special focus on the Irish, North and Baltic Sea. 1.) Vertical Wind Speed Profiles The vertical wind profile above the sea has to be modelled with high accuracy for tip heights up to 160m in order to achieve precise wind resource assessments, to calculate loads and wakes of wind turbines as well as for reliable short-term wind power forecasts. We present an assessment of different models for wind profiles in unstable, neutral and stable thermal stratification. The meso-scale models comprise MM5, WRF and COSMO-EU (LME). Both COSMO-EU from the German Weather Service DWD and WRF use a turbulence closure of 2.5th order - and lead to similar results. Especially the limiting effect of low boundary layer heights on the wind shear in very stable stratification is well captured. In our new WRF-formulation for the mixing length in the Mellor-Yamada-Janjic (MYJ) parameterisation of the Planetary Boundary Layer (PBL-scheme), the master length scale itself depends on the Monin-Obukhov-Length as a parameter for the heat flux effects on the turbulent mixing. This new PBL-scheme shows a better performance for all weather conditions than the original MYJ-scheme. Apart from the low-boundary-layer-effect in very stable situations (which are seldom), standard Monin-Obukhov formulations in combination with the Charnock relation for the sea surface roughness show good agreement with the FINO1-data (German Bight). Interesting results were achieved with two more detailed micro-scale approaches: - the parameterization proposed by Pena, Gryning and Hasager [BLM 2008] that depends on the boundary layer height - our ICWP-model, were the flux

  19. Circulation in the region of the Reykjanes Ridge in June-July 2015

    Science.gov (United States)

    Tillys, Petit; Herle, Mercier; Virginie, Thierry

    2017-04-01

    The Reykjanes Ridge is a major topographic feature of the North-Atlantic Ocean lying south of Iceland that strongly influences the pathways of the upper and lower limbs of the meridional overturning cell. The circulation in the vicinity of the Reykjanes Ridge is anticyclonic and characterized by a southwestward flow (the East Reykjanes Ridge Current, ERRC) along the eastern flank and a northeastward flow (the Irminger Current, IC) along the western flank. Even if it is admitted that the ERRC feeds the IC through a cross-ridge flow, details and magnitude of this circulation remain unclear. In this study, the circulation in the region of the Reykjanes Ridge was investigated based on ADCP and CTDO2 measurements carried out from the R/V Thalassa during the RREX cruise, which provided a snapshot of the water mass distribution and circulation during summer 2015. One hydrographic section followed the top of the Reykjanes Ridge between Iceland and 50˚ N and three other sections were carried out perpendicularly to the ridge at 62˚ N, 58.5˚ N and 56˚ N. Geostrophic transports were estimated by combining ADCP and hydrographic data. Those observations were used to provide an estimate of the circulation around the Ridge and to discuss the meridional evolutions of the ERRC and IC transports along the Ridge and their connection to the cross-Ridge flows. The section along the top of the Reykjanes Ridge allowed us to describe the cross ridge exchanges. A westward flow crossed the Ridge between Iceland and 53˚ N. Its top to bottom integrated transport was estimated at 17.7 Sv. Two main passages were identified for the westward crossing. A first passage is located near 57˚ N (Bight Fracture Zone, BFZ) in agreement with previous studies. More surprisingly, a second passage is located near 59˚ N. The top-to-bottom transports of those two main flows were estimated at 6.5 and 8 Sv respectively. The IC and ERRC top-to-bottom integrated transports were maximum at 58.5˚ N and

  20. Enriching the Web Processing Service

    Science.gov (United States)

    Wosniok, Christoph; Bensmann, Felix; Wössner, Roman; Kohlus, Jörn; Roosmann, Rainer; Heidmann, Carsten; Lehfeldt, Rainer

    2014-05-01

    -T interface. In order to deal with the results of these processing workflows, a server side extension enables the RichWPS Server and its clients to use WPS presentation directives (WPS-PD), a content related enhancement for the standardized WPS schema. We identified essential requirements of the components of our toolset by applying two use cases. The first enables the simplified comparison of modeled and measured data, a common task in hydro-engineering to validate the accuracy of a model. An implementation of the workflow includes reading, harmonizing and comparing two datasets in NetCDF-format. 2D Water level data from the German Bight can be chosen, presented and evaluated in a web client with interactive plots. The second use case is motivated by the Marine Strategy Directive (MSD) of the EU, which demands monitoring, action plans and at least an evaluation of the ecological situation in marine environment. Information technics adapted to those of INSPIRE should be used. One of the parameters monitored and evaluated for MSD is the expansion and quality of seagrass fields. With the view towards other evaluation parameters we decompose the complex process of evaluation of seagrass in reusable process steps and implement those packages as configurable WPS.