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Sample records for models gulf menhaden

  1. Ultrasound detection in the Gulf menhaden requires gas-filled bullae and an intact lateral line

    DEFF Research Database (Denmark)

    Wilson, Maria; Montie, Eric W.; Mann, Kenneth A.

    2009-01-01

    Clupeiform fish species, including the Gulf menhaden (Brevoortia patronus) that belong to the subfamily Alosinae, can detect ultrasound. Clupeiform fishes are unique in that they have specialized gas-filled bullae in the head associated with the ear via the bulla membrane and with the lateral line...... via the lateral recess membrane. It has been hypothesized that the utricle of the inner ear is responsible for ultrasound detection through a specialized connection to the gas-filled bullae complex. Here, we show that the lateral line and its connection to the gas-filled bullae complex via the lateral...... recess are involved in ultrasound detection in Gulf menhaden. Removal of a small portion of the lateral line overlying the lateral recess membrane eliminates the ability of Gulf menhaden to detect ultrasound. We further show that the gas-filled bullae vibrates in response to ultrasound, that the gas...

  2. Trace metal concentrations in menhaden larvae Brevoortia patronus from the northern Gulf of Mexico

    Science.gov (United States)

    Hanson, Peter J.; Hoss, Donald E.

    1986-09-01

    Whole body concentrations of Cu, Zn, Mn and Fe were measured in individual gulf menhaden larvae, Brevoortia patronus (11-18 mm standard length) from coastal waters of the northern Gulf of Mexico as part of a continuing project investigating the mechanisms of biological interaction and effect of trace metals in marine food webs. Larvae were collected at three different times between February 1981 and 1982 at two locations, offshore of Southwest Pass of the Mississippi River and offshore of Galveston, Texas. Fish at the Mississippi location had significantly ( P≤0·05) greater concentrations of all metals compared with those from the Galveston location. No significant ( P>0·05) differences in concentration were detected among the three sampling periods. Menhaden larvae had metal conentrations comparabe to other species of larval fish and zooplankton from the Gulf of Mexico and other coastal waters. Differences in metal concentrations in larvae from the two locations appear to be a subtle response of the fish to differences in the trace metal chemistries of the two coastal areas. Processes influencing metal concentrations are discussed.

  3. Assessment of the toxic potential of polycyclic aromatic hydrocarbons (PAHs) affecting Gulf menhaden (Brevoortia patronus) harvested from waters impacted by the BP Deepwater Horizon Spill.

    Science.gov (United States)

    Olson, Gregory M; Meyer, Buffy M; Portier, Ralph J

    2016-02-01

    Approximately 4.9 million barrels of crude oil and gas were released into the Gulf of Mexico (GoM) from April to July 2010 during the Deepwater Horizon (DWH) spill. This resulted in the possible contamination of marine organisms with polycyclic aromatic hydrocarbons (PAHs), USEPA identified constituents of concern. To determine the impact of the DWH oil spill, Gulf menhaden (Brevoortia patronus), a commercially harvested and significant trophic grazing species, was sampled from two Louisiana coastal regions between the years 2011-2013. Tissue extraction and GC/MS analysis demonstrated measurable concentrations of PAH within menhaden. Analysis yielded total PAHs, carcinogenic equivalents (BaP-TEQ), and mutagenic equivalents (BaP-MEQ) which provided an initial toxic potential assessment of this GoM Fishery. Gulf menhaden contained less total PAH concentrations in 2012 and significantly less in 2013 as compared to 2011 (p PAHs were also significantly reduced (p PAH concentrations and the reduction of BaP-TEQs and MEQs between 2011 and 2013 indicates a diminished input of new source PAHs along with a reduction of carcinogenic and mutagenic PAHs in menhaden populations. The use of Gulf menhaden was successful in determining the acute toxic potential of PAHs contaminating the GoM in the years directly following the DWH spill event.

  4. Investigation using data from ERTS-1 to develop and implement utilization of living marine resources. [availability and distribution of menhaden fish in Mississippi Sound and Gulf waters

    Science.gov (United States)

    Stevenson, W. H. (Principal Investigator); Pastula, E. J., Jr.

    1973-01-01

    The author has identified the following significant results. This 15-month ERTS-1 investigation produced correlations between satellite, aircraft, menhaden fisheries, and environmental sea truth data from the Mississippi Sound. Selected oceanographic, meteorological, and biological parameters were used as indirect indicators of the menhaden resource. Synoptic and near real time sea truth, fishery, satellite imagery, aircraft acquired multispectral, photo and thermal IR information were acquired as data inputs. Computer programs were developed to manipulate these data according to user requirements. Preliminary results indicate a correlation between backscattered light with chlorophyll concentration and water transparency in turbid waters. Eight empirical menhaden distribution models were constructed from combinations of four fisheries-significant oceanographic parameters: water depth, transparency, color, and surface salinity. The models demonstrated their potential for management utilization in areas of resource assessment, prediction, and monitoring.

  5. NMFS Menhaden Biostatistical (Port Samples) Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data set consists of port samples of gulf and Atlantic menhaden from the reduction purse-seine fisheries: data include specimen fork length, weight and age (yrs),...

  6. Atlantic menhaden adult tagging study

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Atlantic menhaden are a schooling forage fish species, which are subject to a large commercial purse seine fishery. Atlantic menhaden are harvested for reduction...

  7. 21 CFR 184.1472 - Menhaden oil.

    Science.gov (United States)

    2010-04-01

    ... hydrogenated menhaden oils are used as edible fats or oils, as defined in § 170.3(n)(12) of this chapter, in... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Menhaden oil. 184.1472 Section 184.1472 Food and... Substances Affirmed as GRAS § 184.1472 Menhaden oil. (a) Menhaden oil. (1) Menhaden oil is prepared from...

  8. Atlantic menhaden processing plant test tagging data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Atlantic menhaden are a schooling forage fish species, which are subject to a large commercial purse seine fishery. Atlantic menhaden are harvested for reduction...

  9. 76 FR 52638 - Fisheries of the Gulf of Mexico and South Atlantic; Southeast Data, Assessment, and Review (SEDAR...

    Science.gov (United States)

    2011-08-23

    ... National Oceanic and Atmospheric Administration RIN 0648-XA654 Fisheries of the Gulf of Mexico and South Atlantic; Southeast Data, Assessment, and Review (SEDAR); Review Workshop for Gulf of Mexico Menhaden and... technical stock assessments of the Gulf of Mexico stock of menhaden and the southeast U.S. stocks of...

  10. Rat Models of Diet-Induced Obesity and High Fat/Low Dose Streptozotocin Type 2 Diabetes: Effect of Reversal of High Fat Diet Compared to Treatment with Enalapril or Menhaden Oil on Glucose Utilization and Neuropathic Endpoints

    Directory of Open Access Journals (Sweden)

    Amey Holmes

    2015-01-01

    Full Text Available We examined whether reversal of high fat diet, stimulating weight loss, compared to two treatments previously shown to have beneficial effects, could improve glucose utilization and peripheral neuropathy in animal models of obesity and type 2 diabetes. Rats were fed a high fat diet and treated with a low dose of streptozotocin to create models of diet induced obesity or type 2 diabetes, respectively. Afterwards, rats were transferred to a normal diet or treated with enalapril or dietary enrichment with menhaden oil for 12 weeks. Obesity and to a greater extent type 2 diabetes were associated with impaired glucose utilization and peripheral neuropathy. Placing obese rats on a normal diet improved glucose utilization. Steatosis but not peripheral neuropathy was improved after placing obese or diabetic rats on a normal diet. Treating obese and diabetic rats with enalapril or a menhaden oil enriched diet generally improved peripheral neuropathy endpoints. In summary, dietary improvement with weight loss in obese or type 2 diabetic rats was not sufficient to correct peripheral neuropathy. These results further stress the need for discovery of a comprehensive treatment for peripheral neuropathy.

  11. Rat Models of Diet-Induced Obesity and High Fat/Low Dose Streptozotocin Type 2 Diabetes: Effect of Reversal of High Fat Diet Compared to Treatment with Enalapril or Menhaden Oil on Glucose Utilization and Neuropathic Endpoints.

    Science.gov (United States)

    Holmes, Amey; Coppey, Lawrence J; Davidson, Eric P; Yorek, Mark A

    2015-01-01

    We examined whether reversal of high fat diet, stimulating weight loss, compared to two treatments previously shown to have beneficial effects, could improve glucose utilization and peripheral neuropathy in animal models of obesity and type 2 diabetes. Rats were fed a high fat diet and treated with a low dose of streptozotocin to create models of diet induced obesity or type 2 diabetes, respectively. Afterwards, rats were transferred to a normal diet or treated with enalapril or dietary enrichment with menhaden oil for 12 weeks. Obesity and to a greater extent type 2 diabetes were associated with impaired glucose utilization and peripheral neuropathy. Placing obese rats on a normal diet improved glucose utilization. Steatosis but not peripheral neuropathy was improved after placing obese or diabetic rats on a normal diet. Treating obese and diabetic rats with enalapril or a menhaden oil enriched diet generally improved peripheral neuropathy endpoints. In summary, dietary improvement with weight loss in obese or type 2 diabetic rats was not sufficient to correct peripheral neuropathy. These results further stress the need for discovery of a comprehensive treatment for peripheral neuropathy.

  12. Northern Gulf Coast Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions in the Gulf of Mexico....

  13. Effect of Treatment with Salsalate, Menhaden Oil, Combination of Salsalate and Menhaden Oil, or Resolvin D1 of C57Bl/6J Type 1 Diabetic Mouse on Neuropathic Endpoints

    Science.gov (United States)

    Yorek, Matthew S.; Coppey, Lawrence J.; Obrosov, Alexander; Kardon, Randy H.

    2016-01-01

    Aims. In this study a streptozotocin induced type 1 diabetes mouse model was used to assess the effectiveness of salsalate, menhaden oil, the combination of salsalate and menhaden oil, or resolvin D1 on neuropathic endpoints. Materials and Methods. Changes in body weight, blood glucose, serum markers for triglycerides, free fatty acids, cholesterol, and resolvin D1, motor and sensory nerve conduction velocities and thermal sensitivity were assessed, as well as performing in vivo confocal microscopy of subepithelial corneal nerves and immunohistochemistry of nerves in the cornea and foot pad. Results. Diabetic animals failed to gain weight and had elevated blood glucose levels. Diabetic mice had slowed nerve conduction velocity, reduced innervation of the foot pad and cornea subepithelial and epithelial layers, and reduced thermal sensitivity. Monotherapy treatment with salsalate, menhaden oil, and resolvin D1 reduced the pathological signs of diabetic neuropathy. The combination of salsalate and menhaden oil also reduced signs of pathology and generated elevated plasma levels of resolvin D1 compared to other groups. Conclusions. Additional studies are needed to determine whether the combination of salsalate and menhaden oil may be more efficacious than monotherapy alone for the treatment of diabetic peripheral neuropathy.

  14. Partial Replacement with Menhaden Oil Improves Peripheral Neuropathy in High-Fat-Fed Low-Dose Streptozotocin Type 2 Diabetic Rat

    Directory of Open Access Journals (Sweden)

    Lawrence J. Coppey

    2012-01-01

    Full Text Available Aims. To determine the effect of partial replacement of a high-fat diet with menhaden oil on diabetic neuropathy in an animal model of type 2 diabetes. Materials and Methods. High-fat/low-dose streptozotocin diabetic rats were used to examine the influence of replacing 50% of the source of the high-fat diet (lard with menhaden oil, a natural source of n-3 fatty acids, on diabetic neuropathy. Endpoints included analyses of glucose tolerance, fatty liver disease, serum and liver fatty acid composition, serum lipid and adiponectin levels, motor and sensory nerve conduction velocity, thermal sensitivity and innervation of the hindpaw. Results. Diabetic rats were insulin resistant and menhaden oil did not improve whole animal glucose utilization. Menhaden oil did not improve elevated HbA1C levels or serum lipid levels but serum levels of adiponectin were significantly increased and hepatic steatosis was significantly improved. Diabetic rats were thermal hypoalgesic, had reduced motor and sensory nerve conduction velocities and intraepidermal nerve fiber profiles were decreased in the hindpaw and these endpoints were significantly improved with menhaden oil. Conclusions. We found that enrichment of a high-fat diet with menhaden oil improved a number of endpoints associated with diabetic neuropathy.

  15. Modeling the Gulf Stream System: How Far from Reality?

    Science.gov (United States)

    Choa, Yi; Gangopadhyay, Avijit; Bryan, Frank O.; Holland, William R.

    1996-01-01

    Analyses of a primitive equation ocean model simulation of the Atlantic Ocean circulation at 1/6 deg horizontal resolution are presented with a focus on the Gulf Stream region. Among many successful features of this simulation, this letter describes the Gulf Stream separation from the coast of North America near Cape Hatteras, meandering of the Gulf Stream between Cape Hatteras and the Grand Banks, and the vertical structure of temperature and velocity associated with the Gulf Stream. These results demonstrate significant improvement in modeling the Gulf Stream system using basin- to global scale ocean general circulation models. Possible reasons responsible for the realistic Gulf Stream simulation are discussed, contrasting the major differences between the present model configuration and those of previous eddy resolving studies.

  16. Partial Replacement with Menhaden Oil Improves Peripheral Neuropathy in High-Fat-Fed Low-Dose Streptozotocin Type 2 Diabetic Rat

    OpenAIRE

    Coppey, Lawrence J.; Amey Holmes; Davidson, Eric P.; Yorek, Mark A.

    2012-01-01

    Aims. To determine the effect of partial replacement of a high-fat diet with menhaden oil on diabetic neuropathy in an animal model of type 2 diabetes. Materials and Methods. High-fat/low-dose streptozotocin diabetic rats were used to examine the influence of replacing 50% of the source of the high-fat diet (lard) with menhaden oil, a natural source of n-3 fatty acids, on diabetic neuropathy. Endpoints included analyses of glucose tolerance, fatty liver disease, serum and liver fatty acid com...

  17. Dispersed oil toxicity tests with biological species indigenous to the Gulf of Mexico. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Fucik, K.W.; Carr, K.A.; Balcom, B.J.

    1994-08-01

    Static and flowthrough aquatic acute toxicity testing protocols were utilized on eggs and larvae of seven commercially important invertebrates and fishes from the Gulf of Mexico. Test organisms were exposed to Central and Western Gulf oils, dispersed oil, and Corexit 9527. Species included brown shrimp (Penaeus aztecus), white shrimp (Penaeus setiferus), blue crab (Callinectes sapidus), eastern oyster (Crassostrea virginica), red drum (Sciaenops ocellatus), inland silverside (Menidia berylina), and spot (Leiosomus xanthurus). Atlantic menhaden (Brevoortia tyrannus) was also tested because gulf menhaden were not available. Mysids (Mysidopsis bahia) were evaluated as part of a chronic toxicity assessment.

  18. Gulf of Mexico dissolved oxygen model (GoMDOM) research and quality assurance project plan

    Science.gov (United States)

    An integrated high resolution mathematical modeling framework is being developed that will link hydrodynamic, atmospheric, and water quality models for the northern Gulf of Mexico. This Research and Quality Assurance Project Plan primarily focuses on the deterministic Gulf of Me...

  19. Regional CMS Modeling: Southwest Florida Gulf Coast

    Science.gov (United States)

    2016-05-01

    counties and over 70 miles of southwest Florida shoreline along the Gulf of Mexico . The study region is entirely within the USACE Jacksonville...2 Figure 1. Sediment budget extent and active USACE Jacksonville District (SAJ) projects in Pinellas, Manatee, and Sarasota Counties, FL. METHOD ...The CMS is a product of the Coastal Inlets Research Program (http://cirp.usace. army.mil), a USACE Navigation Research Development and Technology

  20. Bio-Physical Ocean Modeling in the Gulf of Mexico

    Science.gov (United States)

    2009-01-01

    SS11/G (Rev. 12- efl ] (o) Bio-Physical Ocean Modeling in the Gulf of Mexico Sergio deRada, Robert A. Arnone, Stephanie Anderson Naval Research...for viewing the model results interactively and dynamically in real-time. Initial assessment of the model prediction skill is presented along with...comprehensive picture of the ocean environment. In mutual benefit, the numerical solution gains skill from the assimilation of observational data which are

  1. Marginal production in the Gulf of Mexico - II. Model results

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, Mark J.; Yu, Yunke [Center for Energy Studies, Louisiana State University, Baton Rouge, LA 70803 (United States)

    2010-08-15

    In the second part of this two-part article on marginal production in the Gulf of Mexico, we estimate the number of committed assets in water depth less than 1000 ft that are expected to be marginal over a 60-year time horizon. We compute the expected quantity and value of the production and gross revenue streams of the gulf's committed asset inventory circa. January 2007 using a probabilistic model framework. Cumulative hydrocarbon production from the producing inventory is estimated to be 1056 MMbbl oil and 13.3 Tcf gas. Marginal production from the committed asset inventory is expected to contribute 4.1% of total oil production and 5.4% of gas production. A meta-evaluation procedure is adapted to present the results of sensitivity analysis. Model results are discussed along with a description of the model framework and limitations of the analysis. (author)

  2. Understanding Gulf War Illness: An Integrative Modeling Approach

    Science.gov (United States)

    2015-10-01

    Repeating this propagation analysis for all 26 markers we found:  Important trigger effects for several markers in blood and brain in response to LPS...Computational Biology Cytokines Deregulated Balance Diisopropyl Phosphorofluoridate Drug Treatment Electrocardiogram Exercise Physiology Gulf War Illness...continue 30% Conduct wheel running acute and chronic exercise tests to simulate the exercise model in humans 4-12 25% Combine tests of acute and

  3. [A biogeochemical model for the Gulf of Nicoya, Costa Rica].

    Science.gov (United States)

    Tabash Blanco, Farid A

    2007-03-01

    In agreement with the Broecker and Penn two-boxes model, I generated a biogeochemical balance model for the Gulf of Nicoya (Guanacaste, Costa Rica) using two nutrient reservoirs: surface water and deep water. The mixing zone was located at a depth of 20 m. There is a balance between surface waters descending to the bottom and upwelling waters that carry nutrients and other chemical elements to the surface. The main source of nitrogen (nitrate), was the outlet of the Tempisque and Tárcoles rivers. The Gulf of Nicoya is a net source of Dissolved Inorganic Nitrogen (DIN) with an availability rate of 87 x 10(3) mol day(-1) in the dry season and 3044 x 10(3) mol day(-1)in the rainy season. Dissolved Inorganic Phosphate (DIP) was estimated in 27 mol day(-1) in the dry season and 207 mol day(-1) in the rainy season. The dynamics of these biolimited nutrients, in relation to runoff seasonal variations, fits the biological processes reported for the gulf, for example, for variations in primary productivity levels, and maturity and reproduction seasons for species with short and long life cycles.

  4. Model outputs - Developing end-to-end models of the Gulf of California

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to develop spatially discrete end-to-end models of the northern Gulf of California, linking oceanography, biogeochemistry, food web...

  5. Tidal regime in Gulf of Kutch, west coast of India, by 2D model

    Digital Repository Service at National Institute of Oceanography (India)

    Unnikrishnan, A; Gouveia, A; Vethamony, P.

    A 2D barotropic numerical model is developed for the Gulf of Kutch with a view to synthesize available information on tides and currents in the Gulf. A comparison of model results with moored current meter observations shows that the model...

  6. The Ancillary Harvest of Atlantic Menhaden, Brevoortia tyrannus, Roe on the North Carolina Coast

    OpenAIRE

    Smith, Joseph W.; Ahrenholz, Dean W.

    2000-01-01

    Gravid Atlantic menhaden, Brevoortia tyrannus, are available along the central coast of North Carolina during the fall and are harvested by the purse-seine fleet from the port of Beaufort. Virtually all of the catch, sexually immature fish included, is reduces to fish meal, fish oil, and fish solubles; however, minor quantities of roe from ripening female menhaden are extracted for local consupmtion. Routine and selective port sampling information was used to characterize the seasonal and bio...

  7. Modeling the mesoscale eddy field in the Gulf of Alaska

    Science.gov (United States)

    Xiu, Peng; Chai, Fei; Xue, Huijie; Shi, Lei; Chao, Yi

    2012-05-01

    Mesoscale anticyclonic eddies are a common feature in the Gulf of Alaska (GOA). A three-dimensional circulation model is used to examine the general characteristics of eddies in the GOA during 1993-2009. Using an eddy detection algorithm, we tracked on average 6.5 eddies formed each year from the modeled results and 6.9 eddies from altimeter data. Modeled eddy characteristics agree with the remote sensing derived eddy statistics in terms of eddy magnitude, propagation speed, and eddy-core diameter. From the model results, strong seasonal and interannual variations were found in both the number and areal coverage of GOA eddies. At the seasonal scale, more eddies are observed to form from March to May, while the eddy-covered area usually peaks around October. At the interannual scale, our results suggest the years with large eddy-covered area do not necessarily have more eddies generated. The long-term variation of eddy-covered area in the GOA is modulated by El Niño/Southern Oscillation (ENSO) events through altering the local wind stress. Model results indicate one typical Haida eddy could transport 37×1018 J of heat and 27 km3 of freshwater from the shelf to the central gulf. The equivalent fluxes caused by Haida eddies are comparable with the annual mean of net heat flux and freshwater flux from the atmosphere into the ocean in the Haida region, implying that mesoscale eddies are important sources contributing to the heat and freshwater budgets.

  8. Providing Flaxseed Oil but Not Menhaden Oil Protects against OVX Induced Bone Loss in the Mandible of Sprague-Dawley Rats

    Directory of Open Access Journals (Sweden)

    Amanda B. Longo

    2016-09-01

    Full Text Available Higher intakes of polyunsaturated fatty acids (PUFA are associated with benefits at several skeletal sites in postmenopausal women and in rodent models, but the effect of PUFA-containing oils on tooth-supporting alveolar bone of the mandible has not been studied. Moreover, direct comparison of the effect of flaxseed oil (a source of alpha-linolenic acid (ALA and menhaden oil (a source of eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA is unknown. One-month old female Sprague-Dawley rats (n = 48 were randomized to and fed a diet containing flaxseed oil or menhaden oil from one to six months of age. At three months of age, rats were randomized to receive SHAM or ovariectomy (OVX surgery (n = 12/diet. The inter-radicular septum below the first molar of the mandible was imaged at 6 months of age (study endpoint using micro-computed tomography (μCT at a resolution of 9 μm. As expected, OVX significantly reduced percent bone volume (BV/TV, connectivity density (Conn. D., trabecular number (Tb. N., and increased trabecular separation (Tb. Sp. compared to SHAM rats (p < 0.001. However, post hoc analysis revealed these differences were present in rats fed menhaden oil but not those fed flaxseed oil. These results suggest that providing flaxseed oil, possibly through its high ALA content, provides protection against the OVX-induced alveolar bone loss in rats.

  9. Numerical modelling of tides and tidal currents in the Gulf of Kutch

    Digital Repository Service at National Institute of Oceanography (India)

    Unnikrishnan, A.S.

    An application of a two-dimensional tidal model to study the tidal regime in the Gulf of Kutch is made. This is with a view to synthesise various information on tides and currents that are available in the Gulf. A comparison of surface elevations...

  10. Numerical modeling of the winter circulation of the Gulf of Trieste (northern Adriatic

    Directory of Open Access Journals (Sweden)

    Boris PETELIN

    2006-12-01

    Full Text Available Numerical simulations of the winter circulation in and around the Gulf of Trieste are presented. The model, based on the architecture of the Princeton Ocean Model, gave reasonable results for circulation in the Gulf during the winter period, when the dominant bora wind is blowing. Three model runs with different initial and surface boundary conditions show that there is an outflow along the shallow northern coastline of the Gulf and over the surface of the major part of the area, and an inflow at depth in the central and southern parts of the Gulf. However, the variability of the temperature and salinity fields when vertical fluxes of heat and salinity are present cause a weak outflow in an area near the southern part of the Gulf, and make the general circulation pattern more complex.

  11. Influence of dietary menhaden oil on 7,12-dimethylbenzanthracene induced mammary tumorigenesis in rats

    Energy Technology Data Exchange (ETDEWEB)

    O' Connor, T.P.; Peterson, F.; Campbell, T.C.

    1986-03-05

    The effect of dietary menhaden oil on 7,12-dimethylbenzanthracene (DMBA) induced mammary tumorigenesis was examined in female Sprague-Dawley rats. Rats were obtained at age 28 days and acclimated until age 50 days when they received a single i.g. dose of 5 mg DMBA dissolved in 1 ml corn oil. Rats were then randomly assigned to one of four treatment groups with 25 rats per group. One group was fed a diet based on fish protein (freeze-dried cod) and corn oil (F/C). The second group received a diet based on fish protein and menhaden oil (F/M). The third group received a casein based diet with corn oil as the lipid source (C/C). The fourth group was fed a casein based diet with menhaden oil as the lipid source (C/M). Both the protein and lipid sources were fed at a level of 20% by weight of the diets. Rats were palpated weekly to check for mammary tumor development and the experiment was terminated 24 weeks after DMBA administration. Rats fed menhaden oil as a lipid source (F/M and C/M groups) developed significantly fewer mammary tumors than animals on the corn oil based diets (F/C and C/C groups, respectively). Thus, menhaden oil, rich in omega-3 fatty acids, significantly inhibited the development of DMBA induced mammary tumors in this experiment.

  12. Etiology and pathogenesis of skin ulcers in menhaden, Brevoortia tyrannis: does Pfiesteria piscicida play a role?

    Science.gov (United States)

    Blazer, V.; Vogelbein, W.K.; Densmore, C.; Kator, H.; Zwerner, D.; Lilley, J.

    2000-01-01

    The toxic dinoflagellate, Pfiesteria piscicida, is widely blamed for adverse human health effects, acute fish kills and skin lesion events in fishes, particularly menhaden, Brevoortia tyrannis, inhabiting coastal waters from Delaware to North Carolina, USA. In response, we initiated studies to clarify the etiology and pathogenesis of presumed 'Pfiesteria-specific' menhaden skin lesions. Histopathologically, all lesions (>150 fish examined) were associated with a highly invasive and pathogenic fungus eliciting severe tissue necrosis and intense granulomatous inflammation. Severity and extent of the host response indicates that ulcers were at least 1 week old or older. Maryland and Virginia currently use menhaden ulcers as one of several indicators of local Pfiesteria activity. However, their chronic nature, advanced age, and consistent fungal involvement suggest that their use for this purpose may not be valid. We recently isolated an Aphanomyces sp. from the menhaden lesions which by appearance in culture, temperature growth curves, pathogenicity studies in snakehead and positive immunohistochemical staining with polyclonal antibodies suggest the infectious agent is A. invadans (cause of epizootic ulcerative syndrome in Asia, Japan and Australia) or a very closely related species. Ongoing research will address pathogenicity of the fungus in menhaden, genetic comparisons of isolates, and the role of environmental stressors, including P. piscicida, in initiation of the infection. Copyright (C) 2000.

  13. Improved Hypoxia Modeling for Nutrient Control Decisions in the Gulf of Mexico

    Science.gov (United States)

    Habib, Shaid; Pickering, Ken; Tzortziou, Maria; Maninio, Antonio; Policelli, Fritz

    2010-01-01

    As required by the Harmful Algal Bloom and Hypoxia Research Control Act of 1998, the Mississippi River/Gulf of Mexico Watershed Nutrient Task Force issued the 2001 Gulf Hypoxia Action Plan (updated in 2008). In response to the Gulf Hypoxia Action Plan of 2001 (updated in 2008), the EPA Gulf of Mexico Hypoxia Modeling and Monitoring Project has established a detailed model for the Mississippi-Attchafalaya River Basin which provides a capability to forecast the multi-source nutrient loading to the Gulf and the subsequent bio-geochemical processes leading to hypoxic conditions and subsequent effects on Gulf habitats and fisheries. The primary purpose of the EPA model is to characterize the impacts of nutrient management actions, or proposed actions on the spatial and temporal characteristics of the Gulf hypoxic zone. The model is expected to play a significant role in determining best practices and improved strategies for incentivizing nutrient reduction strategies, including installation of on-farm structures to reduce sediment and nutrient runoff, use of cover crops and other agricultural practices, restoration of wetlands and riparian buffers, improved waste water treatment and decreased industrial nitrogen emissions. These decisions are currently made in a fragmented way by federal, state, and local agencies, using a variety of small scale models and limited data. During the past three years, EPA has collected an enormous amount of in-situ data to be used in the model. We believe that the use of NASA satellite data products in the model and for long term validation of the model has the potential to significantly increase the accuracy and therefore the utility of the model for the decision making described above. This proposal addresses the Gulf of Mexico Alliance (GOMA) priority issue of reductions in nutrient inputs to coastal ecosystem. It further directly relates to water quality for healthy beaches and shellfish beds and wetland and coastal conservation

  14. MANAGEMENT MODEL FOR THE SUSTAINABILITY OF THE FISHERY RESOURCES IN THE GULF OF NICOYA, COSTA RICA

    OpenAIRE

    Pacheco-Urpí, Oscar P; Salas, Silvia; Sierra-Sierra, Luis

    2013-01-01

    The state of the management of fishery resources and management strategies for their sustainability are established in the Gulf of Nicoya. The model for sustainable fishing management in Gulf of Nicoya is constructed using approaches based on defined management strategies and on perceived needs and weaknesses. This model unfolds within the context of integral human development in hand with strategies for the conservation of fishery resources within the context of capacity development for comp...

  15. Gulf of California species and catch spatial distributions and historical time series - Developing end-to-end models of the Gulf of California

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to develop spatially discrete end-to-end models of the northern Gulf of California, linking oceanography, biogeochemistry, food web...

  16. Fresh water balance of the Gulf Stream system in a regional model study

    Energy Technology Data Exchange (ETDEWEB)

    Gerdes, R. [Alfred-Wegener-Institut fuer Polar- und Meeresforschung, Bremerhaven (Germany); Biastoch, A. [California Univ., San Diego, La Jolla, CA (United States). Scripps Inst. of Oceanography; Redler, R. [SCAI Inst. for Algorithms and Scientific Computing, German National Research Center for Information Technology, Sankt Augustin (Germany)

    2001-11-01

    We investigate the dependence of surface fresh water fluxes in the Gulf Stream and North Atlantic Current (NAC) area on the position of the stream axis which is not well represented in most ocean models. To correct this shortcoming, strong unrealistic surface fresh water fluxes have to be applied that lead to an incorrect salt balance of the current system. The unrealistic surface fluxes required by the oceanic component may force flux adjustments and may cause fictitious long-term variability in coupled climate models. To identify the important points in the correct representation of the salt balance of the Gulf Stream a regional model of the northwestern part of the subtropical gyre has been set up. Sensitivity studies are made where the westward flow north of the Gulf Stream and its properties are varied. Increasing westward volume transport leads to a southward migration of the Gulf Stream separation point along the American coast. The salinity of the inflow is essential for realistic surface fresh water fluxes and the water mass distribution. The subpolar-subtropical connection is important in two ways: The deep dense flow from the deep water mass formation areas sets up the cyclonic circulation cell north of the Gulf Stream. The surface and mid depth flow of fresh water collected at high northern latitudes is mixed into the Gulf Stream and compensates for the net evaporation at the surface. (orig.)

  17. Modelling and assessment of the impact of radiocesium and radiostrontium contamination in the Thermaikos Gulf, Greece

    Energy Technology Data Exchange (ETDEWEB)

    Eleftheriou, G., E-mail: gelefthe@central.ntua.gr [Department of Physics, National Technical University of Athens (Greece); Institute of Oceanography, Hellenic Centre for Marine Research (Greece); Monte, L., E-mail: monte.luigi@fastwebnet.it [ENEA, Roma (Italy); Brittain, J.E. [Natural History Museum, University of Oslo (Norway); Tsabaris, C. [Institute of Oceanography, Hellenic Centre for Marine Research (Greece)

    2015-11-15

    A radiological model for {sup 137}Cs and {sup 90}Sr dispersion in the marine environment of the Thermaikos Gulf, Greece, and the river catchments draining into the Gulf, is presented. The model, developed and implemented within the MOIRA-PLUS decision support system, integrates appropriate site-specific information. The model's performance has been tested using the available empirical {sup 137}Cs activity concentration data in abiotic and biotic components of the gulf since the Chernobyl accident. Further, this paper describes the results of a modelling exercise performed within the IAEA's EMRAS II international modelling programme to estimate the environmental sensitivity of this characteristic Mediterranean coastal marine environment following radioactive contamination. The radiation doses to humans after a single hypothetical instantaneous deposition of 1000 Bq m{sup −2}, assuming that all of their food intake from the marine pathway comes from the local environment, were calculated. The obtained results are consistent with estimates from other models for different coastal marine environments in the frame of the above-mentioned EMRAS exercise. - Highlights: • The Decision Support System (DSS) MOIRA-PLUS was customised to Thermaikos Gulf. • Model results were compared with empirical data to adjust parameter values. • The environmental sensitivity of the Gulf to {sup 90}Sr and {sup 137}Cs pollution was assessed. • Radiation doses from marine and fresh water pathways were compared. • The dose from fresh water pathways is notably higher than that from marine pathways.

  18. Effect of combination therapy consisting of enalapril, α-lipoic acid, and menhaden oil on diabetic neuropathy in a high fat/low dose streptozotocin treated rat.

    Science.gov (United States)

    Davidson, Eric P; Holmes, Amey; Coppey, Lawrence J; Yorek, Mark A

    2015-10-15

    We have previously demonstrated that treating diabetic rats with enalapril, an angiotensin converting enzyme (ACE) inhibitor, α-lipoic acid, an antioxidant, or menhaden oil, a natural source of omega-3 fatty acids can partially improve diabetic peripheral neuropathy. In this study we sought to determine the efficacy of combining these three treatments on vascular and neural complications in a high fat fed low dose streptozotocin treated rat, a model of type 2 diabetes. Rats were fed a high fat diet for 8 weeks followed by a 30 mg/kg dose of streptozotocin. Eight weeks after the onset of hyperglycemia diabetic rats were treated with a combination of enalapril, α-lipoic acid and menhaden oil. Diabetic rats not receiving treatment were continued on the high fat diet. Glucose clearance was impaired in diabetic rats and significantly improved with treatment. Diabetes caused steatosis, elevated serum lipid levels, slowing of motor and sensory nerve conduction, thermal hypoalgesia, reduction in intraepidermal nerve fiber profiles, decrease in cornea sub-basal nerve fiber length and corneal sensitivity and impairment in vascular relaxation to acetylcholine and calcitonin gene-related peptide in epineurial arterioles of the sciatic nerve. Treating diabetic rats with the combination of enalapril, α-lipoic acid and menhaden oil reversed all these deficits to near control levels except for motor nerve conduction velocity which was also significantly improved compared to diabetic rats but remained significantly decreased compared to control rats. These studies suggest that a combination therapeutic approach may be most effective for treating vascular and neural complications of type 2 diabetes.

  19. Effects of model physics on hypoxia simulations for the northern Gulf of Mexico: A model intercomparison

    Science.gov (United States)

    Fennel, Katja; Laurent, Arnaud; Hetland, Robert; Justić, Dubravko; Ko, Dong S.; Lehrter, John; Murrell, Michael; Wang, Lixia; Yu, Liuqian; Zhang, Wenxia

    2016-08-01

    A large hypoxic zone forms every summer on the Texas-Louisiana Shelf in the northern Gulf of Mexico due to nutrient and freshwater inputs from the Mississippi/Atchafalaya River System. Efforts are underway to reduce the extent of hypoxic conditions through reductions in river nutrient inputs, but the response of hypoxia to such nutrient load reductions is difficult to predict because biological responses are confounded by variability in physical processes. The objective of this study is to identify the major physical model aspects that matter for hypoxia simulation and prediction. In order to do so, we compare three different circulation models (ROMS, FVCOM, and NCOM) implemented for the northern Gulf of Mexico, all coupled to the same simple oxygen model, with observations and against each other. By using a highly simplified oxygen model, we eliminate the potentially confounding effects of a full biogeochemical model and can isolate the effects of physical features. In a systematic assessment, we found that (1) model-to-model differences in bottom water temperatures result in differences in simulated hypoxia because temperature influences the uptake rate of oxygen by the sediments (an important oxygen sink in this system), (2) vertical stratification does not explain model-to-model differences in hypoxic conditions in a straightforward way, and (3) the thickness of the bottom boundary layer, which sets the thickness of the hypoxic layer in all three models, is key to determining the likelihood of a model to generate hypoxic conditions. These results imply that hypoxic area, the commonly used metric in the northern Gulf which ignores hypoxic layer thickness, is insufficient for assessing a model's ability to accurately simulate hypoxia, and that hypoxic volume needs to be considered as well.

  20. Enriching the diet with menhaden oil improves peripheral neuropathy in streptozotocin-induced type 1 diabetic rats.

    Science.gov (United States)

    Coppey, Lawrence J; Davidson, Eric P; Obrosov, Alexander; Yorek, Mark A

    2015-02-01

    The purpose of this study was to determine the effect of supplementing the diet of type 1 diabetic rats with menhaden oil on diabetic neuropathy. Menhaden oil is a natural source for n-3 fatty acids, which have been shown to have beneficial effects in cardiovascular disease and other morbidities. Streptozotocin-induced diabetic rats were used to examine the influence of supplementing their diet with 25% menhaden oil on diabetic neuropathy. Both prevention and intervention protocols were used. Endpoints included motor and sensory nerve conduction velocity, thermal and mechanical sensitivity, and innervation and sensitivity of the cornea and hindpaw. Diabetic neuropathy as evaluated by the stated endpoints was found to be progressive. Menhaden oil did not improve elevated HbA1C levels or serum lipid levels. Diabetic rats at 16-wk duration were thermal hypoalgesic and had reduced motor and sensory nerve conduction velocities, and innervation and sensitivity of the cornea and skin were impaired. These endpoints were significantly improved with menhaden oil treatment following the prevention or intervention protocol. We found that supplementing the diet of type 1 diabetic rats with menhaden oil improved a variety of endpoints associated with diabetic neuropathy. These results suggest that enriching the diet with n-3 fatty acids may be a good treatment strategy for diabetic neuropathy.

  1. Barotropic tidal model for the Bombay High, Gulf of Khambhat and surrounding areas

    Digital Repository Service at National Institute of Oceanography (India)

    Unnikrishnan, A.S.; Shetye, S.R.; Michael, G.S.

    A barotropic model is developed for the shelf region off the central west coast of India, which includes the regions of Bombay High and Gulf of Khambhat, in order to simulate tides and tidal currents in the region. The model is forced by a composite...

  2. Providing Flaxseed Oil but Not Menhaden Oil Protects against OVX Induced Bone Loss in the Mandible of Sprague-Dawley Rats.

    Science.gov (United States)

    Longo, Amanda B; Ward, Wendy E

    2016-01-01

    Higher intakes of polyunsaturated fatty acids (PUFA) are associated with benefits at several skeletal sites in postmenopausal women and in rodent models, but the effect of PUFA-containing oils on tooth-supporting alveolar bone of the mandible has not been studied. Moreover, direct comparison of the effect of flaxseed oil (a source of alpha-linolenic acid (ALA)) and menhaden oil (a source of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)) is unknown. One-month old female Sprague-Dawley rats (n = 48) were randomized to and fed a diet containing flaxseed oil or menhaden oil from one to six months of age. At three months of age, rats were randomized to receive SHAM or ovariectomy (OVX) surgery (n = 12/diet). The inter-radicular septum below the first molar of the mandible was imaged at 6 months of age (study endpoint) using micro-computed tomography (μCT) at a resolution of 9 μm. As expected, OVX significantly reduced percent bone volume (BV/TV), connectivity density (Conn. D.), trabecular number (Tb. N.), and increased trabecular separation (Tb. Sp.) compared to SHAM rats (p oil but not those fed flaxseed oil. These results suggest that providing flaxseed oil, possibly through its high ALA content, provides protection against the OVX-induced alveolar bone loss in rats.

  3. Detection of polycyclic aromatic hydrocarbons (PAHs) in raw menhaden fish oil using fluorescence spectroscopy: Method development.

    Science.gov (United States)

    Pena, Edwin A; Ridley, Lauren M; Murphy, Wyatt R; Sowa, John R; Bentivegna, Carolyn S

    2015-09-01

    Raw menhaden fish oil was developed for biomonitoring polycyclic aromatic hydrocarbons (PAHs) using fluorescence spectroscopy. Menhaden (Genus Brevoortia) were collected in 2010 and/or 2011 from Delaware Bay, New Jersey, USA; James River, Virginia, USA; Vermillion Bay, Louisiana, USA (VBLA); and Barataria Bay, Louisiana, USA (BBLA). Barataria Bay, Louisiana received heavy oiling from the Deepwater Horizon oil spill. Method development included determining optimal wavelengths for PAH detection, fish oil matrix interferences, and influence of solvent concentration on extraction. Results showed that some fish oils contained high molecular weight PAH-like compounds in addition to other fluorescent compounds such as albumin and vitamin A and vitamin E. None of these naturally occurring compounds interfered with detection of high molecular weight PAHs. However, data suggested that the lipid component of fish oil was altering fluorescence spectra by supporting the formation of PAH excimers. For example, the most intense excitation wavelength for hydroxypyrene shifted from Ex285/Em430 to Ex340/Em430. Comparison of Deepwater Horizon crude oil and fish oil spectra indicated that some fish oils contained crude oil-like PAHs. Using wavelengths of Ex360/Em430, fish oil concentrations were calculated as 3.92 μg/g, 0.61 μg/g, and 0.14 μg/g for a Delaware Bay sample, BBLA 2011, and VBLA 2011, respectively. Overall, these results supported using menhaden fish oil to track PAH exposures spatially and temporally.

  4. Modeling the relative importance of nutrient and carbon loads, boundary fluxes, and sediment fluxes on Gulf of Mexico hypoxia

    Science.gov (United States)

    The Louisiana continental shelf (LCS) in the northern Gulf of Mexico experiences bottom water hypoxia in the summer. In order to gain a more fundamental understanding of the controlling factors leading to hypoxia, the Gulf of Mexico Dissolved Oxygen Model (GoMDOM) was applied to ...

  5. PCB modeling in the Gulf of Lions using a 3D coupled model

    Science.gov (United States)

    Alekseenko, Elena; Thouvenin, Bénédicte; Tixier, Céline; Tronczynski, Jacek; Garreau, Pierre; Verney, Romaric; Carlotti, Francois; Espinasse, Boris; Queguiner, Bernard; Baklouti, Melika

    2013-04-01

    Polychlorobiphenyls (PCBs) are synthetic chlorinated organic compounds, which were widely used in many industrial materials. These compounds are persistent, bioaccumulable and toxic for living organisms. The riverine and atmospheric fluxes are the major routes of entry for these chemicals into marine ecosystems, where they are now embedded in natural biogeochemical cycles (Lohmann et al. 2007). Because of bioaccumulation and biomagnification processes in food webs, even nowadays, these compounds may attain dangerous concentration levels especially in the top predators including marine mammals. The contamination of marine biota by PCBs in Mediterranean has also become a matter of concern as the concentrations in some species are at levels putting them at risk for significant biological effects. This may pose potential human health risks in commercial edible species (Carpenter 2006). Planktonic populations play a key role in the trophic food webs in marine ecosystems by the mobilisation and transfer of energy and organic matter towards higher trophic levels. This work aims at a better understanding of the role of plankton in the transfer of PCBs to higher trophic levels in the Gulf of Lions (Mediterranean) by coupling of biogeochemical, ecological and hydrodynamical processes. Modeling is a powerful tool for coupling processes of different disciplines and scales. The recent development of 3D hydrodynamic, hydrosedimentary and biogeochemical models in the Mediterranean (André et al, 2005,2009, Ulses et al, 2008, Dufois et al, 2008, Auger et al, 2011), enables feasibility testing of coupling these models with transfer processes of chemical contaminants. The lack of detailed observations in the sea and the significant uncertainty on contaminants inputs prevent from a proper validation of such modeling tests. However, these tools are very useful to assess the influence of fast processes on the transfer of contaminants to bioaccumulative species. Sensitivity analysis

  6. Modelling of PCB trophic transfer in the Gulf of Lions; 3D coupled model application

    Science.gov (United States)

    Alekseenko, Elena; Thouvenin, Benedicte; Tronczynsky, Jacek; Carlotti, Francois; Garreau, Pierre; Tixier, Celine; Baklouti, Melika

    2017-04-01

    This work aims at assessing the role of plankton in the transfer of PCBs to higher trophic levels in the Gulf of Lions (NW Mediterranean Sea) using a 3D modelling approach, which is coupling biogeochemical and hydrodynamical processes and taking into account the physical-chemical properties of PCBs. Transport of various PCB species were simulated during one year: total dissolved, freely dissolved, particulate, biosorbed on plankton, assimilated by zooplankton. PCB budgets and fluxes into the Gulf of Lions between various species were governed by different processes, such as: adsorption/desorption, bacteria and plankton mortality, zooplankton excretion, grazing, mineralization, volatilization and biodegradation. CB153 (2,2',4,4',5,5' hexachlorobiphényle) congener have been considered in the model, since it presents a large amount of PCB among the other congeners in the environment of the Gulf of Lions. At first, the simulated PCBs distributions within particulate matter and plankton were compared with available in-situ measurements (COSTAS and Merlumed field campaigns) performed in the Gulf of Lions. Two size classes of plankton X (60μ msuspended solids have been considered for the comparison. In general, the magnitudes of CB153 concentrations within two size classes of plankton in April are comparable to the measured ones except the eastern station C1. The magnitudes of living CB153 concentrations in January are less close to the measured ones in vicinity of the Rhone River. Then, the analyses of spatial-temporal variations of PCB within different compartments and within three different zones (coastal, intermediate and offshore zones) of GoL have been performed in order to advance in understanding the contamination pathways from air and water to plankton. For all zones CB153 concentration is raising in January and in July 2010, what is linked with two Rhone River flood events started in the middle of December 2009 and in the middle of June 2010. In all zones

  7. Nutrient biogeochemical cycles in the Gulf of Riga: scaling up field studies with a mathematical model

    Science.gov (United States)

    Savchuk, Oleg P.

    2002-05-01

    A box model has been implemented to understand the large-scale biogeochemical cycles of nitrogen, phosphorus, and silicon in the Gulf of Riga. The large data sets collected within the international Gulf of Riga Project in 1993/1995 were used to validate the model. The comparison to data was useful in scaling up to the gulf-wide level and scrutinizing the conclusions based on short-term field surveys and experimental studies. The simulations indicate that the limiting role was passing from silicon to phosphorus to nitrogen over the seasons of organic production. However, on an annual scale, nutrient limitation was close to the "Redfield equilibrium". Mass balance considerations, based on modeled coupled fluxes, disagree with the conclusions on low sediment denitrification and high phosphorus retention in the pelagic system, which were derived from isolated measurements. Nutrient budgets constructed with the model revealed the high buffer capacity of the Gulf of Riga. The nutrient residence times span a range from 6 years for N to 70 years for Si. The buffering arises from intensive internal recycling in the water body and by the bottom sediments. The budgets indicate that the Gulf retains about two-thirds of external nitrogen and silicon inputs, while phosphorus retention is only 10%. A slow response to external perturbations is demonstrated with numerical experiments run for 15 years under 50% reductions of terrestrial nutrient inputs. These experiments imply that the most effective is the N+P reduction scenario, which resulted in a 20% decrease of primary production after 12 years. A reduction of P resulted in only a 6% decrease of primary production; however, it yielded an 80% drop in the amount of nitrogen fixation.

  8. Modeling lost production from destroyed platforms in the 2004-2005 Gulf of Mexico hurricane seasons

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, Mark J.; Yu, Yunke [Center for Energy Studies, Louisiana State University, Energy Coast and Environment Building, Nicholson Extension Drive, Baton Rouge, LA 70803 (United States); Jablonowski, Christopher J. [Department of Petroleum and Geosystems Engineering, The University of Texas at Austin, 1 University Station C0300, Austin, TX 78712-0228 (United States)

    2009-09-15

    Hurricanes Ivan, Katrina, and Rita passed through the Gulf of Mexico during 2004 and 2005 and resulted in the largest number of destroyed and damaged offshore oil and gas structures in the history of Gulf operations. In the final official government assessment, a total of 126 platforms were destroyed and over 183 structures were identified as having extensive damage. Production associated with wells and structures that are not redeveloped are classified as lost. The purpose of this paper is to derive functional relations that describe the likely contribution the collection of destroyed assets would have made to future production in the Gulf of Mexico. We estimate that the total remaining reserves from the set of destroyed structures range in value between 1.3 and 4.5 billion depending on the assumptions employed. We summarize the impact of the storms on the Gulf of Mexico oil and gas infrastructure and discuss the main issues involved in redevelopment decision making. A meta-model analytic framework is applied to perform sensitivity analysis and to explore the interactions of assumptions on model output. A discussion of the limitations of the analysis is presented. (author)

  9. Modeling and Mapping Oyster Norovirus Outbreak Risks in Gulf of Mexico Using NASA MODIS Aqua Data

    Science.gov (United States)

    Deng, Z.; Wang, J.

    2015-12-01

    Norovirus is a highly infectious virus and the leading cause of foodborne disease outbreaks such as oyster norovirus outbreaks. Currently, there is no vaccine to prevent norovirus infection and no drug to treat it. This paper presents an integrated modeling and mapping framework for predicting the risk of norovirus outbreaks in oyster harvesting waters in the Northern Gulf of Mexico coast. The framework involves (1) the construction of three novel remote sensing algorithms for the retrieval of sea surface salinity, sea surface temperature, and gage height (tide level) using NASA MODIS Aqua data; (2) the development of probability-based Artificial Neural Network (ANN) model for the prediction of oyster norovirus outbreak risk, and (3) the application of the Local Indicators of Spatial Association (LISA) for mapping norovirus outbreak risks in oyster harvesting areas in the Northern Gulf of Mexico using the remotely sensed NASA data, retrieved data from the three remote sensing algorithms, and the ANN model predictions. The three remote sensing algorithms are able to correctly retrieve 94.1% of sea surface salinity, 94.0% of sea surface temperature, and 77.8% of gage height observed along the US coast, including the Pacific coast, the Gulf of Mexico coast, and the Atlantic coast. The gage height, temperature, and salinity are the three most important explanatory variables of the ANN model in terms of spatially distributed input variables. The ANN model is capable of hindcasting/predicting all oyster norovirus outbreaks occurred in oyster growing areas along the Gulf of Mexico coast where environmental data are available. The integrated modeling and mapping framework makes it possible to map daily risks of norovirus outbreaks in all oyster harvesting waters and particularly the oyster growing areas where no in-situ environmental data are available, greatly improving the safety of seafood and reducing outbreaks of foodborne disease.

  10. A biophysical model of S. aurita early life history in the northern Gulf of Guinea

    Science.gov (United States)

    Koné, Vamara; Lett, Christophe; Penven, Pierrick; Bourlès, Bernard; Djakouré, Sandrine

    2017-02-01

    S. aurita is the most abundant small pelagic fish in the northern Gulf of Guinea. Its reproduction and recruitment depend crucially on environmental conditions. We developed a biophysical model of S. aurita early life history by coupling offline an individual-based model with the regional oceanic modeling system (ROMS). We used this model to investigate the main factors driving variability in eggs and larval dispersal and survival in the northern Gulf of Guinea. Precisely, individuals were released from different spawning areas along the coast and tracked for a period of 28 days corresponding to their planktonic phase. Individuals that remained in the coastal recruitment areas at an age more than 7 days, at which they can supposedly actively retain themselves in a favorable area, were considered as recruited. Simulation results show the importance of the spawning areas around Cape Palmas and Cape Three Points where cyclonic eddies trap eggs and larvae along the coast, preventing their advection offshore by the Guinea Current. The spawning period also plays a key role in the recruitment success, with highest coastal retention obtained during the major upwelling period (July-September). We find that a second retention peak can occur during the minor upwelling period (February-March) when larval mortality due to temperature is included in the model. These results are in general agreement with knowledge of S. aurita reproduction in the northern Gulf of Guinea.

  11. Habitat Suitability Index Models: Gulf of Mexico American Oyster

    Science.gov (United States)

    Cake, Edwin W.

    1983-01-01

    The American or eastern oyster (Crassostrea virrinica [Gmelin]), a bivalve in the family Ostreidae, is an important commercia and recreational species along the Atlantic and Gulf of Mexico coasts of North America and other areas (U.S. Pacific coast and Hawaii) where it has been introduced (Galtsoff 1964). It evolved over the last 25 million years (Miocene and Pliocene epochs) from an ancestral, Atlantic-Pacific species that also gave rise to the Central American oyster of the Pacific coast, Crassostrea corteziensis (Hertlein) (Stenzel 1971). It evolved to fill a eurytopic niche in coastal estuaries where it forms massive reefs in nearshore bays, sounds, lagoons, and river mouths. Its existence depends on suitable substratum (cultch and firm bottom sediments) and acceptable sal-inity conditions. The location and distribution of oyster reefs in a salt marsh-estuari ne ecosystem are not acci denta 1; rather, they result from the interacti on of many bi 01 ogi ca 1, chemica1, geo1ogi ca1, and phys i ca 1 processes (Butler 1954a; Marshall 1954; Bahr and Lanier 1981).

  12. Study of Sediment Transportation in the Gulf of Kachchh, using 3D Hydro-dynamic Model Simulation and Satellite Data

    Digital Repository Service at National Institute of Oceanography (India)

    Kunte, P.D.

    . Modeling is, therefore, the integrated development of mathematical equations, logical rules and constraints and a computer program embodying the equations, the logical rules and the solutions to them. Simulation on the other hand, is the experimental... in the Gulf of Kachchh without considering influence of other factors except M2 tide components. It seems that surface current velocity in the Gulf is mainly controlled by the tide system. The COSMOS numerical modeling results also confirmed this conclusion...

  13. Dietary olive oil and menhaden oil mitigate induction of lipogenesis in hyperinsulinemic corpulent JCR:LA-cp rats: microarray analysis of lipid-related gene expression.

    Science.gov (United States)

    Deng, Xiong; Elam, Marshall B; Wilcox, Henry G; Cagen, Lauren M; Park, Edwards A; Raghow, Rajendra; Patel, Divyen; Kumar, Poonam; Sheybani, Ali; Russell, James C

    2004-12-01

    In the corpulent James C. Russell corpulent (JCR:LA-cp) rat, hyperinsulinemia leads to induction of lipogenic enzymes via enhanced expression of sterol-regulatory-binding protein (SREBP)-1c. This results in increased hepatic lipid production and hypertriglyceridemia. Information regarding down-regulation of SREBP-1c and lipogenic enzymes by dietary fatty acids in this model is limited. We therefore assessed de novo hepatic lipogenesis and hepatic and plasma lipids in corpulent JCR rats fed diets enriched in olive oil or menhaden oil. Using microarray and Northern analysis, we determined the effect of these diets on expression of mRNA for lipogenic enzymes and other proteins related to lipid metabolism. In corpulent JCR:LA-cp rats, both the olive oil and menhaden oil diets reduced expression of SREBP-1c, with concomitant reductions in hepatic triglyceride content, lipogenesis, and expression of enzymes related to lipid synthesis. Unexpectedly, expression of many peroxisomal proliferator-activated receptor-dependent enzymes mediating fatty acid oxidation was increased in livers of corpulent JCR rats. The menhaden oil diet further increased expression of these enzymes. Induction of SREBP-1c by insulin is dependent on liver x receptor (LXR)alpha. Although hepatic expression of mRNA for LXR itself was not increased in corpulent rats, expression of Cyp7a1, an LXR-responsive gene, was increased, suggesting increased LXR activity. Expression of mRNA encoding fatty acid translocase and ATP-binding cassette subfamily DALD member 3 was also increased in livers of corpulent JCR rats, indicating a potential role for these fatty acid transporters in the pathogenesis of disordered lipid metabolism in obesity. This study clearly demonstrates that substitution of dietary polyunsaturated fatty acid for carbohydrate in the corpulent JCR:LA-cp rat reduces de novo lipogenesis, at least in part, by reducing hepatic expression of SREBP-1c and that strategies directed toward reducing

  14. Floating Circle of Objects Simulation with the Princeton Ocean Model for the Gulf of Thailand

    Directory of Open Access Journals (Sweden)

    Chairote YAIPRASERT

    2005-01-01

    Full Text Available The Princeton Ocean Model (POM was modified to simulate motion of a group of particles floating on the sea surface in the Gulf of Thailand. The particles in this group were set up so that they formed a circle. The radius reflected uncertainties of longitude and latitude directions while the centre was set at the point of interest. POM was incorporated with tidal forcing on the boundary, which included used current forcing on the inflow by wind velocities, high resolution and realistic ocean bottom topography, temperature and salinity. The model domain for the Gulf of Thailand extended from latitude 3°N-14°N and longitude 99°E-109°E. A horizontal grid resolution of 0.1 degree (approximately 11.1 km was used in the model. Therefore, the grids consisted of 101×111 cells. Twenty one levels in sigma coordinate were used in vertical resolution. The model results were verified using TOPEX/Poseidon and JASON satellite data. The results of the simulation were used to gain a better understanding of the sea current and object movement patterns in the Gulf of Thailand.

  15. Marginal production in the Gulf of Mexico - I. Historical statistics and model framework

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, Mark J. [Center for Energy Studies, Louisiana State University, Baton Rouge, LA 70803 (United States)

    2010-08-15

    Experts may disagree on when world oil production will peak, but there is general agreement that marginal fields will contribute a greater percentage of world supply in the future. As fields mature and operations transition into the later stages of their production cycle, decreasing revenue streams, higher operating costs, and fewer upside opportunities lead to declining profitability. Eventually, all properties are abandoned when cost exceeds the revenue of production. In this two-part paper on marginal production in the Gulf of Mexico, the number of marginal structures in the gulf and their expected contribution to future production is forecast using established economic models. In Part 1, a historical perspective on producing assets is provided and the inventory of committed assets is modeled and categorized. We operationalize the definition of marginal production based on a structure's economic limit. The model framework to identify marginal assets in the Gulf of Mexico is discussed and a step-by-step description of the methodology is provided. In Part 2, the results of the model are described. (author)

  16. Modeling and investigation of Gulf El-Zayt wind farm for stability studying during extreme

    Directory of Open Access Journals (Sweden)

    Omar Noureldeen

    2014-03-01

    Full Text Available This paper investigates the impact of extreme gust wind as a case of wind speed variation on a wind farm interconnected electrical grid. The impact of extreme gust wind speed variation on active and reactive power of the wind farms is studied for variable speed wind farm equipped with Doubly Fed Induction Generators (DFIGs. A simulation model of the under implementation 120 MW wind farm at Gulf El-Zayt region, Red Sea, Egypt, is simulated as a case study. A detailed model of extreme gust wind speed variation is implemented and simulated, using MATLAB/Simulink toolbox, based on International Electrotechnical Commission IEC 61400-1 and climate characteristic of Gulf El-Zayt site. The simulation results show the influence of different extreme gust wind speed variations on the fluctuation of active power and reactive power at the Point of Common Coupling (PCC of the studied wind farm.

  17. Neuroinflammatory Pathobiology in Gulf War Illness: Characterization with an Animal Model

    Science.gov (United States)

    2014-06-01

    treatment of GWI. Future studies will benefit from a better understanding of the molecular underpinnings of the immune “priming” in order to...physiological stressors, e.g., heat, exercise and war stress were encountered in theater during the 1991Gulf War and may have contributed to the...neuroinflammation, these GWI-relevant agents were not used in the neurophysiology studies. So the model consisted of CORT in the drinking water for 7 days

  18. Quantitative model of trophic interactions in Beibu Gulf ecosystem in the northern South China Sea

    Institute of Scientific and Technical Information of China (English)

    CHEN Zuozhi; QIU Yongsong; JIA Xiaoping

    2006-01-01

    A mass-balanced model was constructed to determine the flow-energy in a community of fishes and invertebrates in the Beibu Gulf,northern South China Sea using Ecopath and Ecosim software. Input parameters were taken from the literature, except for the biomass of fish groups which was obtained from trawl surveys during October 1997 to May 1999 in the study area. The model consisted of 16 functional groups (boxes), including one marine mammal and seabirds, each representing organisms with a similar role in the food web, and only covered the main trophic flow in the Beibu Gulf ecosystem. The results showed that the food web of Beibu Gulf was dominated by the detrital path and benthic invertebrates played a significant role in transferring energy from the detritus to higher trophic levels; phytoplankton was a primary producer and most utilized as a food source. Fractional trophic levels ranged from 1.0 to 4.08 with marine mammals occupying the highest trophic level. Using network analysis, the system network was mapped into a linear food chain and six discrete trophic levels were found with a mean transfer efficiency of 16.7% from the detritus, 16.2% from the primary producer within the ecosystem. The biomass density of the commercially utilized species estimated by the model is 8.46 t/km2, only 0.48% of the net primary production.

  19. Paleoecologic and biostratigraphic models for pleistocene through miocene foraminiferal assemblages of the Gulf Coast Basin

    Energy Technology Data Exchange (ETDEWEB)

    Breard, S.Q.; Callender, A.D.; Nault, M.J. (Paleo Control Inc., Houston, TX (United States))

    1993-09-01

    We have developed operationally oriented paleoecologic models used in hydrocarbon exploration of the Gulf Coast basin for Pleistocene through Miocene foraminifera and an updated, refined biostratigraphic chart. We also present estimated paleoecologic tolerances for major benthic and planktic foraminiferal markers, and discuss a number of rules and problems encountered in oil industry paleoenvironmental reconstruction. Key benthic paleoenvironmental markers for particular depth zones are graphically presented for the Pleistocene through Miocene. Improvements over previous models include greater use of calcareous and arenaceous foraminiferal species not used or recognized in earlier studies. Finer subdivisions of bathyal paleoenvironments are of particular significance due to current Gulf of Mexico deep-water exploration. Operationally, the abyssal environmental is difficult to recognize due to a reliance of faunal abundance to delineate abyssal from bathyal and the lack of abyssal zone markers. A number of genera and species are identified as having changed habitat preference through time. Some forms have moved progressively into deeper water (Ceratobulimina Cyclammina cancellata and Nonion pompiloides). Conversely, the movement of species into progressively shallower occurrences through time (Pullenia bullodies) appears to be less common. The widespread occurrence of known Gulf of Mexico foraminiferal species from countries such as Mexico, Venezuela, Ecuador, Jamaica, Trinidad, and the Dominican Republic, suggest that these; models have direct application to Neogene studies in Central America, South America, the Caribbean, and the U.S. Gulf Coast. We introduce a variety of deep-water benthic marker foraminifera, many for the first time. These taxa help fill gaps for deeper-water sections where standard benthic marker foraminifera do not occur, helping debunk the popular myth that benthic foraminifera are useless as markers in the exploration of deep-water sections.

  20. Lagrangian velocity statistics of directed launch strategies in a Gulf of Mexico model

    Directory of Open Access Journals (Sweden)

    M. Toner

    2004-01-01

    Full Text Available The spatial dependence of Lagrangian displacement and velocity statistics is studied in the context of a data assimilating numerical model of the Gulf Mexico. In the active eddy region of the Western Gulf, a combination of Eulerian and Lagrangian measures are used to locate strongly hyperbolic regions of the flow. The statistics of the velocity field sampled by sets of drifters launched specifically in these hyperbolic regions are compared to those produced by randomly chosen launch sites. The results show that particle trajectories initialized in hyperbolic regions preferentially sample a broader range of Eulerian velocities than do members of ensembles of randomly launched drifters. The velocity density functions produced by the directed launches compare well with Eulerian velocity pdfs. Implications for the development of launch strategies to improve Eulerian velocity field reconstruction from drifter data are discussed.

  1. Parvalbumin and neuropeptide Y expressing hippocampal GABA-ergic inhibitory interneuron numbers decline in a model of Gulf War illness

    OpenAIRE

    Tarick eMegahed; Bharathi eHattiangady; Bing eShuai; Shetty, Ashok K.

    2015-01-01

    Cognitive dysfunction is amongst the most conspicuous symptoms in Gulf War illness (GWI). Combined exposure to the nerve gas antidote pyridostigmine bromide (PB), pesticides and stress during the Persian Gulf War-1 (PGW-1) are presumed to be among the major causes of GWI. Indeed, our recent studies in rat models have shown that exposure to GWI-related (GWIR) chemicals and mild stress for 4 weeks engenders cognitive impairments accompanied with several detrimental changes in the hippocampus. I...

  2. Species Profiles: Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (Mid-Atlantic): Atlantic Menhaden

    Science.gov (United States)

    1989-08-01

    eggs and larvae (Reintjes descriptions of Atlantic menhaden 1961, 1968; Herman 1963; Kendall and larvae and juveniles . Reintjes 1975; Ferraro 1980a,b...function and community 12 dynamics have received little ENVIRONMENTAL REQUIREMENTS attention. Larvae and juveniles are seasonally important

  3. Modeling pCO2 variability in the Gulf of Mexico

    Science.gov (United States)

    Xue, Zuo; He, Ruoying; Fennel, Katja; Cai, Wei-Jun; Lohrenz, Steven; Huang, Wei-Jen; Tian, Hanqin; Ren, Wei; Zang, Zhengchen

    2016-08-01

    A three-dimensional coupled physical-biogeochemical model was used to simulate and examine temporal and spatial variability of sea surface pCO2 in the Gulf of Mexico (GoM). The model was driven by realistic atmospheric forcing, open boundary conditions from a data-assimilative global ocean circulation model, and observed freshwater and terrestrial nutrient and carbon input from major rivers. A 7-year model hindcast (2004-2010) was performed and validated against ship measurements. Model results revealed clear seasonality in surface pCO2 and were used to estimate carbon budgets in the Gulf. Based on the average of model simulations, the GoM was a net CO2 sink with a flux of 1.11 ± 0.84 × 1012 mol C yr-1, which, together with the enormous fluvial inorganic carbon input, was comparable to the inorganic carbon export through the Loop Current. Two model sensitivity experiments were performed: one without biological sources and sinks and the other using river input from the 1904-1910 period as simulated by the Dynamic Land Ecosystem Model (DLEM). It was found that biological uptake was the primary driver making GoM an overall CO2 sink and that the carbon flux in the northern GoM was very susceptible to changes in river forcing. Large uncertainties in model simulations warrant further process-based investigations.

  4. Integration of numerical modeling and observations for the Gulf of Naples monitoring network

    Science.gov (United States)

    Iermano, I.; Uttieri, M.; Zambianchi, E.; Buonocore, B.; Cianelli, D.; Falco, P.; Zambardino, G.

    2012-04-01

    Lethal effects of mineral oils on fragile marine and coastal ecosystems are now well known. Risks and damages caused by a maritime accident can be reduced with the help of better forecasts and efficient monitoring systems. The MED project TOSCA (Tracking Oil Spills and Coastal Awareness Network), which gathers 13 partners from 4 Mediterranean countries, has been designed to help create a better response system to maritime accidents. Through the construction of an observational network, based on state of the art technology (HF radars and drifters), TOSCA provides real-time observations and forecasts of the Mediterranean coastal marine environmental conditions. The system is installed and assessed in five test sites on the coastal areas of oil spill outlets (Eastern Mediterranean) and on high traffic areas (Western Mediterranean). The Gulf of Naples, a small semi-closed basin opening to the Tyrrhenian Sea is one of the five test-sites. It is of particular interest from both the environmental point of view, due to peculiar ecosystem properties in the area, and because it sustains important touristic and commercial activities. Currently the Gulf of Naples monitoring network is represented by five automatic weather stations distributed along the coasts of the Gulf, one weather radar, two tide gauges, one waverider buoy, and moored physical, chemical and bio-optical instrumentation. In addition, a CODAR-SeaSonde HF coastal radar system composed of three antennas is located in Portici, Massa Lubrense and Castellammare. The system provides hourly data of surface currents over the entire Gulf with a 1km spatial resolution. A numerical modeling implementation based on Regional Ocean Modeling System (ROMS) is actually integrated in the Gulf of Naples monitoring network. ROMS is a 3-D, free-surface, hydrostatic, primitive equation, finite difference ocean model. In our configuration, the model has high horizontal resolution (250m), and 30 sigma levels in the vertical. Thanks

  5. Marine regime shifts in ocean biogeochemical models: a case study in the Gulf of Alaska

    Science.gov (United States)

    Beaulieu, Claudie; Cole, Harriet; Henson, Stephanie; Yool, Andrew; Anderson, Tom; de Mora, Lee; Buitenhuis, Erik T.; Butenschön, Momme; Totterdell, Ian J.; Icarus Allen, J.

    2016-08-01

    Regime shifts have been reported in many marine ecosystems, and are often expressed as an abrupt change occurring in multiple physical and biological components of the system. In the Gulf of Alaska, a regime shift in the late 1970s was observed, indicated by an abrupt increase in sea surface temperature and major shifts in the catch of many fish species. A thorough understanding of the extent and mechanisms leading to such regime shifts is challenged by data paucity in time and space. We investigate the ability of a suite of ocean biogeochemistry models of varying complexity to simulate regime shifts in the Gulf of Alaska by examining the presence of abrupt changes in time series of physical variables (sea surface temperature and mixed-layer depth), nutrients and biological variables (chlorophyll, primary productivity and plankton biomass) using change-point analysis. Our results show that some ocean biogeochemical models are capable of simulating the late 1970s shift, manifested as an abrupt increase in sea surface temperature followed by an abrupt decrease in nutrients and biological productivity. Models from low to intermediate complexity simulate an abrupt transition in the late 1970s (i.e. a significant shift from one year to the next) while the transition is smoother in higher complexity models. Our study demonstrates that ocean biogeochemical models can successfully simulate regime shifts in the Gulf of Alaska region. These models can therefore be considered useful tools to enhance our understanding of how changes in physical conditions are propagated from lower to upper trophic levels.

  6. Lack of a protective effect of menhaden oil on skin tumor promotion by 12-O-tetradecanoylphorbol-13-acetate.

    Science.gov (United States)

    Locniskar, M; Belury, M A; Cumberland, A G; Patrick, K E; Fischer, S M

    1990-09-01

    Fish oil has been shown to have a protective effect in some cancer models. To determine whether fish oil alters skin tumorigenesis, a study was designed using the initiation-promotion mouse skin carcinogenesis model, feeding mice during the promotion stage a constant overall amount of dietary fat (10%) in which the levels of menhaden oil (MO) varied from 0 to 8.5% or corn oil (CO) at 10%. SENCAR mice were initiated with 10 nmol dimethylbenz[a]anthracene. Two weeks later mice were divided into five groups and maintained on one of the following AIN-76 based diets consisting of: 8.5% coconut oil (CT)/1.5% CO (diet A); 1% MO/7.5% CT/1.5% CO (diet B); 4% MO/4.5% CT/1.5% CO (diet C); 8.5% MO/1.5% CO (diet D); or 10% CO (diet E). Two weeks later, promotion with twice weekly applications of 1 micrograms 12-O-tetradecanoylphorbol-13-acetate (TPA) was begun and continued for 24 weeks. No statistically significant differences in kcal food consumed or body wts were observed between diet groups during the study. The final papilloma and carcinoma incidence was not different among the diet groups. However, differences were seen in the rate of papilloma appearance with the group fed diet E (10% CO) being the slowest and diet B being the most rapid. In a parallel study, ornithine decarboxylase activity, a suggested marker of promotion, was greatly elevated in the epidermis of all TPA-treated mice and the effect of diet tended to reflect the different rates of tumor formation observed among the groups. These data indicate that the diets containing fish oil were not protective in the final incidence of tumor formation and suggest that a better understanding of the complex interactions is warranted before recommendations are made to alter the human diet for cancer prevention.

  7. Application of a one-dimensional model to explore the drivers and lability of carbon in the northern Gulf of Mexico

    Science.gov (United States)

    A one-dimensional water quality model, Gulf of Mexico Dissolved Oxygen Model (GoMDOM-1D), was developed to simulate phytoplankton, carbon, nutrients, and dissolved oxygen in Gulf of Mexico. The model was calibrated and corroborated against a comprehensive set of field observation...

  8. Tectonoestratigraphic and Thermal Models of the Tiburon and Wagner Basins, northern Gulf of California Rift System

    Science.gov (United States)

    Contreras, J.; Ramirez Zerpa, N. A.; Negrete-Aranda, R.

    2014-12-01

    The northern Gulf of California Rift System consist sofa series faults that accommodate both normal and strike-slip motion. The faults formed a series of half-greens filled with more than 7 km of siliciclastic suc­cessions. Here, we present tectonostratigraphic and heat flow models for the Tiburón basin, in the southern part of the system, and the Wag­ner basin in the north. The models are constrained by two-dimensional seis­mic lines and by two deep boreholes drilled by PEMEX­-PEP. Analysis of the seismic lines and models' results show that: (i) subsidence of the basins is controlled by high-angle normal faults and by flow of the lower crust, (ii) basins share a common history, and (iii) there are significant differences in the way brittle strain was partitioned in the basins, a feature frequently observed in rift basins. On one hand, the bounding faults of the Tiburón basin have a nested geometry and became active following a west-to-east sequence of activation. The Tiburon half-graben was formed by two pulses of fault activity. One took place during the protogulf extensional phase in the Miocene and the other during the opening of Gulf of California in the Pleistocene. On the other hand, the Wagner basin is the result of two fault generations. During the late-to middle Miocene, the west-dipping Cerro Prieto and San Felipe faults formed a domino array. Then, during the Pleistocene the Consag and Wagner faults dissected the hanging-wall of the Cerro Prieto fault forming the modern Wagner basin. Thermal modeling of the deep borehole temperatures suggests that the heat flow in these basins in the order of 110 mW/m2 which is in agreement with superficial heat flow measurements in the northern Gulf of California Rift System.

  9. U.S. Coastal Relief Model - Western Gulf of Mexico

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NGDC's U.S. Coastal Relief Model (CRM) provides the first comprehensive view of the U.S. coastal zone integrating offshore bathymetry with land topography into a...

  10. U.S. Coastal Relief Model - Central Gulf of Mexico

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NGDC's U.S. Coastal Relief Model (CRM) provides the first comprehensive view of the U.S. coastal zone integrating offshore bathymetry with land topography into a...

  11. Modelling deformation rates in the western Gulf of Corinth: rheological constraints

    Science.gov (United States)

    Cianetti, S.; Tinti, E.; Giunchi, C.; Cocco, M.

    2008-08-01

    The Gulf of Corinth is one of the most active extensional regions in the Mediterranean area characterized by a high rate of seismicity. However, there are still open questions concerning the role and the geometry of the numerous active faults bordering the basin, as well as the mechanisms governing the seismicity. In this paper, we use a 2-D plane strain finite element analysis to constrain the upper crust rheology by modelling the available deformation data (GPS and geomorphology). We consider a SSW-NNE cross-section of the rift cutting the main active normal faults (Aigion, West Eliki and Off-Shore faults). The models run for 650 Kyr assuming an elasto-viscoplastic rheology and 1.3 cmyr-1 horizontal extension as boundary condition (resulting from GPS data). We model the horizontal and vertical deformation rates and the accumulation of plastic strain at depth, and we compare them with GPS data, with long term uplift rates inferred from geomorphology and with the distribution of seismicity, respectively. Our modelling results demonstrate that dislocation on high-angle normal faults in a plastic crustal layer plays a key role in explaining the extremely localized strain within the Gulf of Corinth. Conversely, the contribution of structures such as the antithetic Trizonia fault or the buried hypothetical subhorizontal discontinuity are not necessary to model observed data.

  12. Performance evaluation of WAVEWATCH III model in the Persian Gulf using different wind resources

    Science.gov (United States)

    Kazeminezhad, Mohammad Hossein; Siadatmousavi, Seyed Mostafa

    2017-07-01

    The third-generation wave model, WAVEWATCH III, was employed to simulate bulk wave parameters in the Persian Gulf using three different wind sources: ERA-Interim, CCMP, and GFS-Analysis. Different formulations for whitecapping term and the energy transfer from wind to wave were used, namely the Tolman and Chalikov (J Phys Oceanogr 26:497-518, 1996), WAM cycle 4 (BJA and WAM4), and Ardhuin et al. (J Phys Oceanogr 40(9):1917-1941, 2010) (TEST405 and TEST451 parameterizations) source term packages. The obtained results from numerical simulations were compared to altimeter-derived significant wave heights and measured wave parameters at two stations in the northern part of the Persian Gulf through statistical indicators and the Taylor diagram. Comparison of the bulk wave parameters with measured values showed underestimation of wave height using all wind sources. However, the performance of the model was best when GFS-Analysis wind data were used. In general, when wind veering from southeast to northwest occurred, and wind speed was high during the rotation, the model underestimation of wave height was severe. Except for the Tolman and Chalikov (J Phys Oceanogr 26:497-518, 1996) source term package, which severely underestimated the bulk wave parameters during stormy condition, the performances of other formulations were practically similar. However, in terms of statistics, the Ardhuin et al. (J Phys Oceanogr 40(9):1917-1941, 2010) source terms with TEST405 parameterization were the most successful formulation in the Persian Gulf when compared to in situ and altimeter-derived observations.

  13. Understanding Gulf War Illness: An Integrative Modeling Approach

    Science.gov (United States)

    2016-10-01

    adaptation from the heart to keep the normal functional for this stress (dobutamine), increasing isovolumetric relaxation time (IVRT) and myocardial...isovolumetric contraction and relaxation time. MPI which is the ratio of total activity (index of cardiac overload) was significantly increased in DFP exposure...Sarin Stress Response Target Intervention Therapeutic Interventions Translational Human Clinical Trials Translational Model Treatment 5

  14. Tsunamigenic earthquakes in the Gulf of Cadiz: fault model and recurrence

    Directory of Open Access Journals (Sweden)

    L. M. Matias

    2013-01-01

    Full Text Available The Gulf of Cadiz, as part of the Azores-Gibraltar plate boundary, is recognized as a potential source of big earthquakes and tsunamis that may affect the bordering countries, as occurred on 1 November 1755. Preparing for the future, Portugal is establishing a national tsunami warning system in which the threat caused by any large-magnitude earthquake in the area is estimated from a comprehensive database of scenarios. In this paper we summarize the knowledge about the active tectonics in the Gulf of Cadiz and integrate the available seismological information in order to propose the generation model of destructive tsunamis to be applied in tsunami warnings. The fault model derived is then used to estimate the recurrence of large earthquakes using the fault slip rates obtained by Cunha et al. (2012 from thin-sheet neotectonic modelling. Finally we evaluate the consistency of seismicity rates derived from historical and instrumental catalogues with the convergence rates between Eurasia and Nubia given by plate kinematic models.

  15. Modeling of circulation in the Arabian Gulf and the Sea of Oman: Skill assessment and seasonal thermohaline structure

    Science.gov (United States)

    Al Azhar, Muchamad; Temimi, Marouane; Zhao, Jun; Ghedira, Hosni

    2016-03-01

    Hindcast simulations of the Arabian Gulf and the Sea of Oman using the Regional Ocean Modeling System (ROMS) are quantitatively evaluated with basin-wide hydrographic data and time series measurements. The model shows comparable skill in reproducing moored observations of current velocities structure in upper and bottom depths. The skill in simulating observed temperature is higher of 0.93 (scale 0-1) in upper depths compared to 0.52 in bottom depths. Model results are sensitive to parameterization of water clarity. A lower sensitivity was noticed to KPP, GLS, and MY2.5 turbulence closures. When coastal turbid water parameterization is used, accuracy of the model in reproducing seasonal and spatial variations of temperature and salinity increased by 25% compared to the clear water case whereas only 10% increase was noticed when applying KPP turbulent closure. The model reproduces well anticlockwise circulation in the Gulf. A stronger surface inflow of fresher water to the Arabian Gulf through the Strait of Hormuz is simulated in summer compared to winter conditions, mainly due to upper layer horizontal gradient of density between the Arabian Gulf and the Sea of Oman. Less seasonal variability of outflow between 0.15 and 0.20 m s-1 at 50 m to bottom depth around the Strait of Hormuz was noticed in the model results. Modeled surface layer stratification is stronger in summer than winter and varies spatially in the Arabian Gulf with highest stratification near the Strait of Hormuz. Overall, the stratification in shallow water area of the Arabian Gulf remains low throughout the year.

  16. Application of Thermal Modelling for Geochemical Characterization of Gadvan Formation, Persian Gulf, Iran

    Directory of Open Access Journals (Sweden)

    Ahmad Vaezian

    2014-12-01

    Full Text Available In the this research, the hydrocarbon generation potential of the Gadvan Formation as a probable source rock was investigated in the central part of the Persian Gulf at the borders of Iran. Type and maturity level of kerogen were investigated in six wells using the results of Rock-Eval pyrolysis and compared with results yielded by the modelling software program known as Pars Basin Modeler (PBM. The cross-plot of hydrogen index (HI versus maximum temperature suggests that the Gadvan Formation reached early to mid-maturity stages in the studied area, which means that it could act as a gas prone source rock. Furthermore, the burial and thermal history of the Gadvan Formation was determined in one well. Two methods, Easy %Ro and time-temperature index (TTI were used for the reconstruction of thermal modelling and studying the thermal maturity level in all of the drilled wells reaching the Gadvan Formation. The results of the TTI and Easy %Ro methods were in good agreement and both of confirmed the results of Rock Eval analysis. An integrated approach using different techniques showed that the Gadvan Formation can be classified as a poor gas bearing source rock in the studied area, while its maturity increases towards the southern parts of the Persian Gulf.

  17. Habitat-based cetacean density models for the U.S. Atlantic and Gulf of Mexico

    Science.gov (United States)

    Roberts, Jason J.; Best, Benjamin D.; Mannocci, Laura; Fujioka, Ei; Halpin, Patrick N.; Palka, Debra L.; Garrison, Lance P.; Mullin, Keith D.; Cole, Timothy V. N.; Khan, Christin B.; McLellan, William A.; Pabst, D. Ann; Lockhart, Gwen G.

    2016-03-01

    Cetaceans are protected worldwide but vulnerable to incidental harm from an expanding array of human activities at sea. Managing potential hazards to these highly-mobile populations increasingly requires a detailed understanding of their seasonal distributions and habitats. Pursuant to the urgent need for this knowledge for the U.S. Atlantic and Gulf of Mexico, we integrated 23 years of aerial and shipboard cetacean surveys, linked them to environmental covariates obtained from remote sensing and ocean models, and built habitat-based density models for 26 species and 3 multi-species guilds using distance sampling methodology. In the Atlantic, for 11 well-known species, model predictions resembled seasonal movement patterns previously suggested in the literature. For these we produced monthly mean density maps. For lesser-known taxa, and in the Gulf of Mexico, where seasonal movements were less well described, we produced year-round mean density maps. The results revealed high regional differences in small delphinoid densities, confirmed the importance of the continental slope to large delphinoids and of canyons and seamounts to beaked and sperm whales, and quantified seasonal shifts in the densities of migratory baleen whales. The density maps, freely available online, are the first for these regions to be published in the peer-reviewed literature.

  18. A spatiotemporal model for snow crab (Chionoecetes opilio) stock size in the southern Gulf of St. Lawrence

    DEFF Research Database (Denmark)

    Cadigan, Noel G.; Wade, Elmer; Nielsen, Anders

    2017-01-01

    We develop a high-resolution spatiotemporal model of stock size and harvest rates for snow crab (Chionoecetes opilio) in the southern Gulf of St. Lawrence, which supports an economically important fishery off the east coast of Canada. It is a spatial and weekly model during 1997–2014 that utilize...

  19. 3D Gravity Modeling of Complex Salt Features in the Southern Gulf of Mexico

    Directory of Open Access Journals (Sweden)

    Mauricio Nava-Flores

    2016-01-01

    Full Text Available We present a three-dimensional (3D gravity modeling and inversion approach and its application to complex geological settings characterized by several allochthonous salt bodies embedded in terrigenous sediments. Synthetic gravity data were computed for 3D forward modeling of salt bodies interpreted from Prestack Depth Migration (PSDM seismic images. Density contrasts for the salt bodies surrounded by sedimentary units are derived from density-compaction curves for the northern Gulf of Mexico’s oil exploration surveys. By integrating results from different shape- and depth-source estimation algorithms, we built an initial model for the gravity anomaly inversion. We then applied a numerically optimized 3D simulated annealing gravity inversion method. The inverted 3D density model successfully retrieves the synthetic salt body ensemble. Results highlight the significance of integrating high-resolution potential field data for salt and subsalt imaging in oil exploration.

  20. Ocean modelling and Early-Warning System for the Gulf of Thailand

    Science.gov (United States)

    de Lima Rego, Joao; Yan, Kun; Sisomphon, Piyamarn; Thanathanphon, Watin; Twigt, Daniel; Irazoqui Apecechea, Maialen

    2017-04-01

    Storm surges associated with severe tropical cyclones are among the most hazardous and damaging natural disasters to coastal areas. The Gulf of Thailand (GoT) has been periodically affected by typhoon induced storm surges in the past (e.g. storm Harriet in 1962, storm Gay in 1989 and storm Linda in 1997). Due to increased touristic / economic development and increased population density in the coastal zone, the combined effect and risk of high water level and increased rainfall / river discharge has dramatically increased and are expected to increase in future due to climate change effects. This presentation describes the development and implementation of the first real-time operational storm surge, wave and wave setup forecasting system in the GoT, a joint applied research initiative by Deltares in The Netherlands and the Hydro and Agro Informatics Institute (HAII) in Thailand. The modelling part includes a new hydrodynamic model to simulate tides and storm surges and two wave models (regional and local). The hydrodynamic model is based on Delft3D Flexible Mesh, capable of simulating water levels and detailed flows. The regional and the recently-developed local wave model are based on the SWAN model, a third-generation wave model. The operational platform is based on Delft-FEWS software, which coordinates all the data inputs, the modelling tasks and the automatic forecast exports including overland inundation in the upper Gulf of Thailand. The main objective of the Gulf of Thailand EWS is to provide daily accurate storm surge, wave and wave setup estimates automatically with various data exports possibilities to support this task. It adds a coastal component to HAII's existing practice of providing daily reports on fluvial flood forecasts, used for decision-support in issuing flood warnings for inland water systems in Thailand. Every day, three-day coastal forecasts are now produced based on the latest regional meteorological predictions. Examples are given to

  1. Development of a computer model to predict platform station keeping requirements in the Gulf of Mexico using remote sensing data

    Science.gov (United States)

    Barber, Bryan; Kahn, Laura; Wong, David

    1990-01-01

    Offshore operations such as oil drilling and radar monitoring require semisubmersible platforms to remain stationary at specific locations in the Gulf of Mexico. Ocean currents, wind, and waves in the Gulf of Mexico tend to move platforms away from their desired locations. A computer model was created to predict the station keeping requirements of a platform. The computer simulation uses remote sensing data from satellites and buoys as input. A background of the project, alternate approaches to the project, and the details of the simulation are presented.

  2. Forecasting hypoxia in the Chesapeake Bay and Gulf of Mexico: model accuracy, precision, and sensitivity to ecosystem change

    Energy Technology Data Exchange (ETDEWEB)

    Evans, Mary Anne; Scavia, Donald, E-mail: mevans@umich.edu, E-mail: scavia@umich.edu [School of Natural Resources and Environment, University of Michigan, Ann Arbor, MI 48109 (United States)

    2011-01-15

    Increasing use of ecological models for management and policy requires robust evaluation of model precision, accuracy, and sensitivity to ecosystem change. We conducted such an evaluation of hypoxia models for the northern Gulf of Mexico and Chesapeake Bay using hindcasts of historical data, comparing several approaches to model calibration. For both systems we find that model sensitivity and precision can be optimized and model accuracy maintained within reasonable bounds by calibrating the model to relatively short, recent 3 year datasets. Model accuracy was higher for Chesapeake Bay than for the Gulf of Mexico, potentially indicating the greater importance of unmodeled processes in the latter system. Retrospective analyses demonstrate both directional and variable changes in sensitivity of hypoxia to nutrient loads.

  3. Modeling regulatory policies associated with offshore structure removal requirements in the Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, Mark J. [Center for Energy Studies, Louisiana State University, Energy Coast and Environment Building, Baton Rouge, LA (United States)

    2008-07-15

    Federal regulations require that a lease in the Outer Continental Shelf of the Gulf of Mexico be cleared of all structures within one year after production on the lease ceases, but in recent years, the Minerals Management Service has begun to encourage operators to remove idle (non-producing) structures on producing leases that are no longer ''economically viable''. At the end of 2003, there were 2175 producing structures, 898 idle (non-producing) structures, and 440 auxiliary (never-producing) structures on 1356 active leases; and 329 idle structures and 65 auxiliary structures on 273 inactive leases. The purpose of this paper is to model the impact of alternative regulatory policies on the removal trends of structures and the inventory of idle iron, and to provide first-order estimates of the cost of each regulatory option. A description of the modeling framework and implementation results is presented. (author)

  4. Modelling the influence of Major Baltic Inflows on near-bottom conditions at the entrance of the Gulf of Finland.

    Science.gov (United States)

    Lessin, Gennadi; Raudsepp, Urmas; Stips, Adolf

    2014-01-01

    A coupled hydrodynamic-biogeochemical model was implemented in order to estimate the effects of Major Baltic Inflows on the near-bottom hydrophysical and biogeochemical conditions in the northern Baltic Proper and the western Gulf of Finland during the period 1991-2009. We compared results of a realistic reference run to the results of an experimental run where Major Baltic Inflows were suppressed. Further to the expected overall decrease in bottom salinity, this modelling experiment confirms that in the absence of strong saltwater inflows the deep areas of the Baltic Proper would become more anoxic, while in the shallower areas (western Gulf of Finland) near-bottom average conditions improve. Our experiment revealed that typical estuarine circulation results in the sporadic emergence of short-lasting events of near-bottom anoxia in the western Gulf of Finland due to transport of water masses from the Baltic Proper. Extrapolating our results beyond the modelled period, we speculate that the further deepening of the halocline in the Baltic Proper is likely to prevent inflows of anoxic water to the Gulf of Finland and in the longer term would lead to improvement in near-bottom conditions in the Baltic Proper. Our results reaffirm the importance of accurate representation of salinity dynamics in coupled Baltic Sea models serving as a basis for credible hindcast and future projection simulations of biogeochemical conditions.

  5. Challenges in modelling spatiotemporally varying phytoplankton blooms in the Northwestern Arabian Sea and Gulf of Oman

    Directory of Open Access Journals (Sweden)

    S. Sedigh Marvasti

    2015-07-01

    Full Text Available We examine interannual variability of phytoplankton blooms in northwestern Arabian Sea and Gulf of Oman. Satellite data (SeaWIFS ocean color shows two climatological blooms in this region, a wintertime bloom peaking in February and a summertime bloom peaking in September. A pronounced anti-correlation between the AVISO sea surface height anomaly (SSHA and chlorophyll is found during the wintertime bloom. On a regional scale, interannual variability of the wintertime bloom is thus dominated by cyclonic eddies which vary in location from one year to another. These results were compared against the outputs from three different 3-D Earth System models. We show that two coarse (1° models with the relatively complex biogeochemistry (TOPAZ capture the annual cycle but neither eddies nor the interannual variability. An eddy-resolving model (GFDL CM2.6 with a simpler biogeochemistry (miniBLING displays larger interannual variability, but overestimates the wintertime bloom and captures eddy-bloom coupling in the south but not in the north. The southern part of the domain is a region with a much sharper thermocline and nutricline relatively close to the surface, in which eddies modulate diffusive nutrient supply to the surface (a mechanism not previously emphasized in the literature. We suggest that for the model to simulate the observed wintertime blooms within cyclones, it will be necessary to represent this relatively unusual nutrient structure as well as the cyclonic eddies. This is a challenge in the Northern Arabian Sea as it requires capturing the details of the outflow from the Persian Gulf.

  6. Gulf War agent exposure causes impairment of long-term memory formation and neuropathological changes in a mouse model of Gulf War Illness.

    Directory of Open Access Journals (Sweden)

    Zuchra Zakirova

    Full Text Available Gulf War Illness (GWI is a chronic multisymptom illness with a central nervous system component such as memory deficits, neurological, and musculoskeletal problems. There are ample data that demonstrate that exposure to Gulf War (GW agents, such as pyridostigmine bromide (PB and pesticides such as permethrin (PER, were key contributors to the etiology of GWI post deployment to the Persian GW. In the current study, we examined the consequences of acute (10 days exposure to PB and PER in C57BL6 mice. Learning and memory tests were performed at 18 days and at 5 months post-exposure. We investigated the relationship between the cognitive phenotype and neuropathological changes at short and long-term time points post-exposure. No cognitive deficits were observed at the short-term time point, and only minor neuropathological changes were detected. However, cognitive deficits emerged at the later time point and were associated with increased astrogliosis and reduction of synaptophysin staining in the hippocampi and cerebral cortices of exposed mice, 5 months post exposure. In summary, our findings in this mouse model of GW agent exposure are consistent with some GWI symptom manifestations, including delayed onset of symptoms and CNS disturbances observed in GWI veterans.

  7. Surface chlorophyll distributions in the upper Gulf of Thailand investigated using satellite imagery and ecosystem model

    Science.gov (United States)

    Buranapratheprat, Anukul

    MERIS data and Nutrient-Phytoplankton-Zooplankton-Detritus (NPZD) ecosystem model coupled with the Princeton Ocean Model (POM), were used to investigate seasonal variations in surface chlorophyll distributions and their controlling factors to clarify phytoplankton dynamics in the upper Gulf of Thailand. Chlorophyll maps were produced by application on MERIS Level 2 data an empirical algorithm derived from the regression analysis of the relationship between chlorophyll-a concentration and remote sensing reflectance ratio. The results indicated that the patterns of seasonal chlorophyll distributions corresponded to local wind and water circulations. The model simulation highlighted the importance of river water as a significant nutrient source, and its movement after discharge into the sea is controlled by seasonal circulations. High chlorophyll concentration located along the western coast following the direction of counter-clockwise circulation, forced by the northeast winds, while chlorophyll accumulation was observed in the northeastern corner of the gulf due to clockwise circulation, driven by the southwest winds. These key simulated results are consistent with those of field observations and satellite images captured in the same periods of time, and also described seasonal shifting of blooming areas previously reported. Sensitivity analysis of simulated chlorophyll distributions suggested that not only nutrients but also wind-induced vertical movement plays a significant role in controlling phytoplankton growth. Plankton blooms occur in zones of upwelling or where vertical diffusivities are low. Increasing nutrients in the water column due to river loads leads to increasing potential for severe plankton blooms when other photosynthetic factors, such as water stability and light, are optimized. The knowledge of seasonal patterns of blooming can be used to construct environmental risk maps which are very useful for planning to mitigate the eutrophic problems

  8. Modelling tide-driven currents and residual eddies in the Gulf of Kachchh and their seasonal variability: A marine environmental planning perspective

    Digital Repository Service at National Institute of Oceanography (India)

    Babu, M.T.; Vethamony, P.; Desa, E.

    Tide-driven currents in the Gulf of Kachchh (GoK) have been studied using MIKE21 hydrodynamic model. The results are validated with measured currents for three different periods characterized by different wind fields. Comparison of model results...

  9. The Arabian Gulf University College of Medicine and Medical Sciences: a successful model of a multinational medical school.

    Science.gov (United States)

    Hamdy, Hossam; Anderson, M Brownell

    2006-12-01

    In the late 1970s, leaders of the Arabian [corrected] Gulf countries proposed a novel idea of a joint educational and cultural venture: establishing a new regional university based in the Kingdom of Bahrain that would be managed as a multinational consortium of Gulf countries including Saudi Arabia, United Arab Emirates, Kuwait, Oman, Qatar, and Bahrain. It was intended to promote higher education and research in the Gulf region; to serve the development needs of the region; to reflect the unique economic, social, and cultural attributes of the Gulf communities and their environments; and to respond to the health care needs of the member countries. Since its inception in 1982, the College of Medicine and Medical Sciences (CMMS) at Arabian Gulf University (AGU) has adopted the educational philosophy of problem-based learning (PBL) and self-directed, student-centered education. The curriculum is integrated, with early introduction of education to foster clinical skills and professional competencies. The strategic alliance with the health care systems in Bahrain and other Gulf regions has created a successful model of efficient and effective initialization of health care resources in the community. The experience that has accumulated at the AGU-CMMS from introducing innovative medical education has allowed it to take a leadership position in medical education in the Gulf region. The original goals of this unique experiment have been realized along with unanticipated outcomes of spearheading changes in medical education in the Gulf region. Old and new medical schools have adopted several characteristics of the AGU educational program. Several elements contributed to its success: a clear vision of providing quality medical education and realizing and sustaining this vision by a supportive leadership at the university and college levels; an alliance with the regional health care systems; a dedicated faculty who have been able to work as a team while continually

  10. The Application of Remotely Sensed Data and Models to Benefit Conservation and Restoration Along the Northern Gulf of Mexico Coast

    Science.gov (United States)

    Quattrochi, D. A.; Estes, M. G., Jr.; Al-Hamdan, M. Z.; Thom, R.; Woodruff, D.; Judd, C.; Ellis, J. T.; Swann, R.; Johnson, H., III

    2010-12-01

    New data, tools, and capabilities for decision making are significant needs in the northern Gulf of Mexico and other coastal areas. The goal of this project is to support NASA’s Earth Science Mission Directorate and its Applied Science Program and the Gulf of Mexico Alliance by producing and providing NASA data and products that will benefit decision making by coastal resource managers and other end users in the Gulf region. Data and research products are being developed to assist coastal resource managers adapt and plan for changing conditions by evaluating how climate changes and urban expansion will impact land cover/land use (LCLU), hydrodynamics, water properties, and shallow water habitats; to identify priority areas for conservation and restoration; and to distribute datasets to end-users and facilitating user interaction with models. The proposed host sites for data products are NOAA’s National Coastal Data Development Center Regional Ecosystem Data Management, and Mississippi-Alabama Habitat Database. Tools will be available on the Gulf of Mexico Regional Collaborative website with links to data portals to enable end users to employ models and datasets to develop and evaluate LCLU and climate scenarios of particular interest. These data will benefit the Mobile Bay National Estuary Program in ongoing efforts to protect and restore the Fish River watershed and around Weeks Bay National Estuarine Research Reserve. The usefulness of data products and tools will be demonstrated at an end-user workshop.

  11. The Application of Remotely Sensed Data and Models to Benefit Conservation and Restoration Along the Northern Gulf of Mexico Coast

    Science.gov (United States)

    Quattrochi, Dale; Estes, Maurice, Jr.; Al-Hamdan, Mohammad; Thom, Ron; Woodruff, Dana; Judd, Chaeli; Ellis, Jean; Swann, Roberta; Johnson, Hoyt, III

    2010-01-01

    New data, tools, and capabilities for decision making are significant needs in the northern Gulf of Mexico and other coastal areas. The goal of this project is to support NASA s Earth Science Mission Directorate and its Applied Science Program and the Gulf of Mexico Alliance by producing and providing NASA data and products that will benefit decision making by coastal resource managers and other end users in the Gulf region. Data and research products are being developed to assist coastal resource managers adapt and plan for changing conditions by evaluating how climate changes and urban expansion will impact land cover/land use (LCLU), hydrodynamics, water properties, and shallow water habitats; to identify priority areas for conservation and restoration; and to distribute datasets to end-users and facilitating user interaction with models. The proposed host sites for data products are NOAA s National Coastal Data Development Center Regional Ecosystem Data Management, and Mississippi-Alabama Habitat Database. Tools will be available on the Gulf of Mexico Regional Collaborative website with links to data portals to enable end users to employ models and datasets to develop and evaluate LCLU and climate scenarios of particular interest. These data will benefit the Mobile Bay National Estuary Program in ongoing efforts to protect and restore the Fish River watershed and around Weeks Bay National Estuarine Research Reserve. The usefulness of data products and tools will be demonstrated at an end-user workshop.

  12. Modeling pCO2 variability in the Gulf of Mexico

    Directory of Open Access Journals (Sweden)

    Z. Xue

    2014-08-01

    Full Text Available A three-dimensional coupled physical–biogeochemical model was used to simulate and examine temporal and spatial variability of surface pCO2 in the Gulf of Mexico (GoM. The model is driven by realistic atmospheric forcing, open boundary conditions from a data-assimilative global ocean circulation model, and observed freshwater and terrestrial nutrient and carbon input from major rivers. A seven-year model hindcast (2004–2010 was performed and was validated against in situ measurements. The model revealed clear seasonality in surface pCO2. Based on the multi-year mean of the model results, the GoM is an overall CO2 sink with a flux of 1.34 × 1012 mol C yr−1, which, together with the enormous fluvial carbon input, is balanced by the carbon export through the Loop Current. A sensitivity experiment was performed where all biological sources and sinks of carbon were disabled. In this simulation surface pCO2 was elevated by ~ 70 ppm, providing the evidence that biological uptake is a primary driver for the observed CO2 sink. The model also provided insights about factors influencing the spatial distribution of surface pCO2 and sources of uncertainty in the carbon budget.

  13. LANDSAT follow-on experiment: Gulf of Mexico menhaden and thread herring resources investigation. [Mississippi and Louisiana

    Science.gov (United States)

    Savastano, K. (Principal Investigator); Kemmerer, A. J.; Faller, K.

    1976-01-01

    The author has identified the following significant results. The most significant achievement realized is the successful mapping of high probability fishing areas from LANDSAT MSS data for two Mississippi Sound missions.

  14. Gulf stream separation dynamics

    Science.gov (United States)

    Schoonover, Joseph

    Climate models currently struggle with the more traditional, coarse ( O(100 km) ) representation of the ocean. In these coarse ocean simulations, western boundary currents are notoriously difficult to model accurately. The modeled Gulf Stream is typically seen exhibiting a mean pathway that is north of observations, and is linked to a warm sea-surface temperature bias in the Mid-Atlantic Bight. Although increased resolution ( O(10 km) ) improves the modeled Gulf Stream position, there is no clean recipe for obtaining the proper pathway. The 70 year history of literature on the Gulf Stream separation suggests that we have not reached a resolution on the dynamics that control the current's pathway just south of the Mid-Atlantic Bight. Without a concrete knowledge on the separation dynamics, we cannot provide a clean recipe for accurately modeling the Gulf Stream at increased resolutions. Further, any reliable parameterization that yields a realistic Gulf Stream path must express the proper physics of separation. The goal of this dissertation is to determine what controls the Gulf Stream separation. To do so, we examine the results of a model intercomparison study and a set of numerical regional terraforming experiments. It is argued that the separation is governed by local dynamics that are most sensitive to the steepening of the continental shelf, consistent with the topographic wave arrest hypothesis of Stern (1998). A linear extension of Stern's theory is provided, which illustrates that wave arrest is possible for a continuously stratified fluid.

  15. Microencapsulation of menhaden fish oil containing soluble rice bran fiber using spray drying technology.

    Science.gov (United States)

    Wan, Yuting; Bankston, Joseph David; Bechtel, Peter J; Sathivel, Subramaniam

    2011-05-01

    Emulsion (EFMO) containing purified menhaden oil (PMO) and soluble rice bran fiber (SRBF) was dried in a pilot scale spray dryer and produced microencapsulated PMO with SRBF (MFMO). EFMO had well isolated spherical droplets with the size of 1 to 10 μm and showed pseudoplastic fluid and viscoelastic characteristics. EFMO had lower lipid oxidation than the emulsion containing PMO without SRBF when both emulsions were stored at 20 and 40 °C for 88 h, which indicated that the SRBF reduced the lipid oxidation in the EFMO. The estimated MFMO production rate (3.45 × 10(-5) kg dry solids/s) was higher than the actual production rate (2.31 × 10(-5) kg dry solids/s). The energy required to spray dry the EFMO was 12232 kJ/kg of emulsion. EPA and DHA contents of MFMO were 11.52% and 4.51%, respectively. The particle size of 90% MFMO ranged from 8 to 62 μm, and the volume-length diameter of MFMO was 28.5 μm.

  16. Assessing the Performance of a Northern Gulf of Mexico Tidal Model Using Satellite Imagery

    Directory of Open Access Journals (Sweden)

    Stephen C. Medeiros

    2013-11-01

    Full Text Available Tidal harmonic analysis simulations along with simulations spanning four specific historical time periods in 2003 and 2004 were conducted to test the performance of a northern Gulf of Mexico tidal model. A recently developed method for detecting inundated areas based on integrated remotely sensed data (i.e., Radarsat-1, aerial imagery, LiDAR, Landsat 7 ETM+ was applied to assess the performance of the tidal model. The analysis demonstrates the applicability of the method and its agreement with traditional performance assessment techniques such as harmonic resynthesis and water level time series analysis. Based on the flooded/non-flooded coastal areas estimated by the integrated remotely sensed data, the model is able to adequately reproduce the extent of inundation within four sample areas from the coast along the Florida panhandle, correctly identifying areas as wet or dry over 85% of the time. Comparisons of the tidal model inundation to synoptic (point-in-time inundation areas generated from the remotely sensed data generally agree with the results of the traditional performance assessment techniques. Moreover, this approach is able to illustrate the spatial distribution of model inundation accuracy allowing for targeted refinement of model parameters.

  17. Modeling ocean circulation and biogeochemical variability in the Gulf of Mexico

    Science.gov (United States)

    Xue, Z.; He, R.; Fennel, K.; Cai, W.-J.; Lohrenz, S.; Hopkinson, C.

    2013-11-01

    A three-dimensional coupled physical-biogeochemical model is applied to simulate and examine temporal and spatial variability of circulation and biogeochemical cycling in the Gulf of Mexico (GoM). The model is driven by realistic atmospheric forcing, open boundary conditions from a data assimilative global ocean circulation model, and observed freshwater and terrestrial nitrogen input from major rivers. A 7 yr model hindcast (2004-2010) was performed, and validated against satellite observed sea surface height, surface chlorophyll, and in situ observations including coastal sea level, ocean temperature, salinity, and dissolved inorganic nitrogen (DIN) concentration. The model hindcast revealed clear seasonality in DIN, phytoplankton and zooplankton distributions in the GoM. An empirical orthogonal function analysis indicated a phase-locked pattern among DIN, phytoplankton and zooplankton concentrations. The GoM shelf nitrogen budget was also quantified, revealing that on an annual basis the DIN input is largely balanced by the removal through denitrification (an equivalent of ~ 80% of DIN input) and offshore exports to the deep ocean (an equivalent of ~ 17% of DIN input).

  18. An approximate Kalman filter for ocean data assimilation: An example with an idealized Gulf Stream model

    Science.gov (United States)

    Fukumori, Ichiro; Malanotte-Rizzoli, Paola

    1995-01-01

    A practical method of data assimilation for use with large, nonlinear, ocean general circulation models is explored. A Kalman filter based on approximation of the state error covariance matrix is presented, employing a reduction of the effective model dimension, the error's asymptotic steady state limit, and a time-invariant linearization of the dynamic model for the error integration. The approximations lead to dramatic computational savings in applying estimation theory to large complex systems. We examine the utility of the approximate filter in assimilating different measurement types using a twin experiment of an idealized Gulf Stream. A nonlinear primitive equation model of an unstable east-west jet is studied with a state dimension exceeding 170,000 elements. Assimilation of various pseudomeasurements are examined, including velocity, density, and volume transport at localized arrays and realistic distributions of satellite altimetry and acoustic tomography observations. Results are compared in terms of their effects on the accuracies of the estimation. The approximate filter is shown to outperform an empirical nudging scheme used in a previous study. The examples demonstrate that useful approximate estimation errors can be computed in a practical manner for general circulation models.

  19. A model study of the Gulf Stream Extension intrinsic low-frequency variability

    Science.gov (United States)

    Quattrocchi, Giovanni; Pierini, Stefano; Dijkstra, Henk A.

    2010-05-01

    A process-oriented model study aimed at understanding aspects of the intrinsic low-frequency variability of the Gulf Stream Extension is presented. Reduced-gravity and two-layer shallow water eddy-permitting models are implemented in a domain spanning the latitudes from 10°S to 60°N, with schematic coastlines representing correctly the large-scale shape of the continental boundaries. The forcing, provided by a time-independent climatological wind stress field, is obtained from 41 years (1961-2001) of ECMWF Re-Analysis data. In the two-layer model a Deep Western Boundary Current is introduced through boundary forcing. The dissipative mechanisms are the lateral eddy viscosity (with coefficient A) and the interfacial friction (with coefficient F) and, in the two-layer model, also the bottom friction. Sensitivity experiments are carried out by varying A and F, and the results are interpreted also in terms of dynamical systems theory. For sufficiently high dissipation a steady western boundary current and corresponding extension jet are obtained: their comparison with AVISO altimeter data provides experimental validation of the model setup. Decreasing A and F leads to a first Hopf bifurcation and to the successive transition to chaotic fluctuations characterized by interannual time scales. A thorough analysis is carried out also by considering previous work on more idealized double-gyre flows.

  20. Modeling ocean circulation and biogeochemical variability in the Gulf of Mexico

    Directory of Open Access Journals (Sweden)

    Z. Xue

    2013-05-01

    Full Text Available A three-dimensional coupled physical-biogeochemical model is applied to simulate and examine temporal and spatial variability of circulation and biogeochemical cycling in the Gulf of Mexico (GoM. The model is driven by realistic atmospheric forcing, open boundary conditions from a data assimilative global ocean circulation model, and observed freshwater and terrestrial nutrient input from major rivers. A 7 yr model hindcast (2004–2010 was performed, and validated against satellite observed sea surface height, surface chlorophyll, and in-situ observations including coastal sea-level, ocean temperature, salinity, and nutrient concentration. The model hindcast revealed clear seasonality in nutrient, phytoplankton and zooplankton distributions in the GoM. An Empirical Orthogonal Function analysis indicated a phase-locked pattern among nutrient, phytoplankton and zooplankton concentrations. The GoM shelf nutrient budget was also quantified, revealing that on an annual basis ~80% of nutrient input was denitrified on the shelf and ~17% was exported to the deep ocean.

  1. Radiative transfer modeling applied to sea water constituent determination. [Gulf of Mexico

    Science.gov (United States)

    Faller, K. H.

    1979-01-01

    Optical radiation from the sea is influenced by pigments dissolved in the water and contained in discrete organisms suspended in the sea, and by pigmented and unpigmented inorganic and organic particles. The problem of extracting the information concerning these pigments and particulates from the optical properties of the sea is addressed and the properties which determine characteristics of the radiation that a remote sensor will detect and measure are considered. The results of the application of the volume scattering function model to the data collected in the Gulf of Mexico and its environs indicate that the size distribution of the concentrations of particles found in the sea can be predicted from measurements of the volume scattering function. Furthermore, with the volume scattering function model and knowledge of the absorption spectra of dissolved pigments, the radiative transfer model can compute a distribution of particle sizes and indices of refraction and concentration of dissolved pigments that give an upwelling light spectrum that closely matches measurements of that spectrum at sea.

  2. Lagrangian predictability of high-resolution regional models: the special case of the Gulf of Mexico

    Directory of Open Access Journals (Sweden)

    P. C. Chu

    2004-01-01

    Full Text Available The Lagrangian prediction skill (model ability to reproduce Lagrangian drifter trajectories of the nowcast/forecast system developed for the Gulf of Mexico at the University of Colorado at Boulder is examined through comparison with real drifter observations. Model prediction error (MPE, singular values (SVs and irreversible-skill time (IT are used as quantitative measures of the examination. Divergent (poloidal and nondivergent (toroidal components of the circulation attractor at 50m depth are analyzed and compared with the Lagrangian drifter buoy data using the empirical orthogonal function (EOF decomposition and the measures, respectively. Irregular (probably, chaotic dynamics of the circulation attractor reproduced by the nowcast/forecast system is analyzed through Lyapunov dimension, global entropies, toroidal and poloidal kinetic energies. The results allow assuming exponential growth of prediction error on the attractor. On the other hand, the q-th moment of MPE grows by the power law with exponent of 3q/4. The probability density function (PDF of MPE has a symmetrical but non-Gaussian shape for both the short and long prediction times and for spatial scales ranging from 20km to 300km. The phenomenological model of MPE based on a diffusion-like equation is developed. The PDF of IT is non-symmetric with a long tail stretched towards large ITs. The power decay of the tail was faster than 2 for long prediction times.

  3. Topobathymetric Model of the Northern Gulf of Mexico, 1888 to 2013

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Accurate, high-resolution elevation information is vital to understanding the highly dynamic Northern Gulf Coast, with Louisiana being the location of North...

  4. Model Development and Hindcast Simulations of NOAA’s Gulf of Maine Operational Forecast System

    Directory of Open Access Journals (Sweden)

    Zizang Yang

    2016-11-01

    Full Text Available The National Ocean Service (NOS of National Oceanic and Atmospheric Administration is developing an operational nowcast/forecast system for the Gulf of Maine (GoMOFS. The system aims to produce real-time nowcasts and short-range forecast guidance for water levels, 3-dimensional currents, water temperature, and salinity over the broad GoM region. GoMOFS will be implemented using the Regional Ocean Model System (ROMS. This paper describes the system setup and results from a one-year (2012 hindcast simulation. The hindcast performance was evaluated using the NOS standard skill assessment software. The results indicate favorable agreement between observations and model forecasts. The root-mean-squared errors are about 0.12 m for water level, less than 1.5 °C for temperature, less than 1.5 psu for salinity, and less than 0.2 m/s for currents. It is anticipated to complete the system development and the transition into operations in fiscal year 2017.

  5. Investigating the Marine Protected Areas most at risk of current-driven pollution in the Gulf of Finland, the Baltic Sea, using a Lagrangian transport model.

    Science.gov (United States)

    Delpeche-Ellmann, Nicole C; Soomere, Tarmo

    2013-02-15

    The possibility of current-driven propagation of contaminants released along a major fairway polluting the Marine Protected Areas (MPAs) in the Gulf of Finland, the Baltic Sea, is examined using a 3D circulation model, a Lagrangian transport model and statistics. Not surprisingly, the number of hits to the MPA decreases almost linearly with its distance from the fairway. In addition, the potential pollution released during a ship accident with the pollutants carried by currents may affect MPAs at very large distances. Typically, a fairway section approximately 125 km long (covering about 1/3 of the approximate 400-km-long gulf) may serve as a source of pollution for each MPA. The largest MPA (in the Eastern Gulf of Finland) may receive pollution from an approximately 210-km-long section (covering about 1/2 of the entire length of the gulf). This information may be useful in assisting maritime management.

  6. A model-based examination of multivariate physical modes in the Gulf of Alaska

    Science.gov (United States)

    Hermann, A. J.; Ladd, C.; Cheng, W.; Curchitser, E. N.; Hedstrom, K.

    2016-10-01

    We use multivariate output from a hydrodynamic model of the Gulf of Alaska (GOA) to explore the covariance among its physical state and air/sea fluxes. We attempt to summarize this coupled variability using a limited set of patterns, and examine their correlation to three large-scale climate indices relevant to the Northeast Pacific. This analysis is focused on perturbations from monthly climatology of the following attributes of the GOA: sea surface temperature, sea surface height, mixed layer depth, sea surface salinity, latent heat flux, sensible heat flux, shortwave irradiance, net long wave irradiance, currents at 40 m depth, and wind stress. We identified two multivariate modes, both substantially correlated with the Pacific Decadal Oscillation (PDO) and Multivariate El Nino (MEI) indices on interannual timescales, which together account for ~30% of the total normalized variance of the perturbation time series. These two modes indicate the following covarying events during periods of positive PDO/MEI: (1) anomalously warm, wet and windy conditions (typically in winter), with elevated coastal SSH, followed 2-5 months later by (2) reduced cloud cover, with emerging shelf-break eddies. Similar modes are found when the analysis is performed separately on the eastern and western GOA; in general, modal amplitudes appear stronger in the western GOA.

  7. AIRSAR observations of the Gulf Stream with interpretation from sea truth and modeling

    Science.gov (United States)

    Valenzuela, G. R.; Chubb, S. R.; Marmorino, G. O.; Trump, C. L.; Lee, J. S.; Cooper, A. L.; Askari, F.; Keller, W. C.; Kaiser, J. A. C.; Mied, R. P.

    1991-01-01

    On 20 Jul., JPL/DC-8 synthetic aperture radar (SAR) participated in the 17-21 Jul. 1990 NRL Gulf Stream (GS) experiment in preparation for SIR-C missions in 1993, 1994, and 1996 for calibration purposes and to check modes and techniques for operation at our experimental site off the east coast of the US. During this experiment, coordinated and near simultaneous measurements were performed from ship (R/V Cape Henlopen) and other aircraft (NADC/P-3 and NRL/P-3) to address scientific questions relating to the origin of 'slick-like' features observed by Scully-Power, the refraction and modulation of waves by variable currents, the effect of current and thermal fronts on radar imagery signatures and the modification of Kelvin ship wakes by fronts. The JPL/DC-8 and NADC/P-3 SAR's are fully polarimetric systems. Their composite frequency range varies between P- and X-band. We describe in detail the Airborne SAR (AIRSAR) participation in the Jul. 1990 GS experiment and present preliminary results of the ongoing analysis and interpretation of the radar imagery in the context of ground truth, other remote measurements, and modeling efforts.

  8. The effects of menhaden oil, flaxseed oil and a dairy-yeast prebiotic on growth , health , feed conversion , survival , critical maximum temperature, and body composition of sunshine bass

    Science.gov (United States)

    A 12-week feeding trial was conducted with juvenile "sunshine bass" female Morone chrysops x male M. saxatilis using four diets containing two levels of a dairy-yeast prebiotic (0 or 2%) and either menhaden fish oil or flaxseed oil as a lipid source. The objective was to determine the main and inte...

  9. Full replacement of menhaden fish meal protein by low-gossypol cottonseed flour protein in the diet of juvenile black sea bass Centropristis striata

    Science.gov (United States)

    Eight iso-nitrogeneous (46% crude protein) and iso-lipidic (14% crude lipid) diets were formulated and prepared to replace menhaden fish meal (FM) protein (59.5% CP) by low-gossypol glandless meal (GCSM) protein (50.4% CP), solvent-extracted cottonseed meal (SCSM) protein (53.8% protein) and high go...

  10. Naval Reseaarch Laboratory Gulf of Mexico Geoid Model Texas Reference Center Pilot Project

    Science.gov (United States)

    Prouty, D. B.; Lyle, S. D.; Roman, D. R.; Mulcare, D. M.; Jeffress, G.; Sadovski, A.; Aiken, C. L.; Smith, R.; Childers, V. A.; Brozena, J. M.

    2007-05-01

    The purpose of this project is to improve elevations in Texas and nearby regions for flooding, mapping and hurricane preparedness. The U.S. Navy Department's Naval Research Laboratory and Texas A&M University- Corpus Christi are planning an aircraft-based gravity data collection effort along the Gulf of Mexico and the southern boundary of the United States. This project will utilize the Naval Airborne Gravity modeling system to improve elevations along the coast and throughout the United States in support of shallow-water navigation, aviation, and ground monitoring systems used by federal, state and local public safety agencies. The current project plan will address the issue of inconsistencies in the gravity field from onshore to offshore, facilitate the identification of systematic problems and otherwise help resolve issues related to existing, legacy gravity data. The widespread and increasing use of GPS for height determinations fundamentally depends on the use of a geoid height model to convert GPS-derived heights into heights above mean sea level. Current geoid models are inadequate. Accurate, homogeneous gravity measurements are essential for the computation of geoid models. To address the inadequate gravity data set for the US, the Naval Research Laboratory (NRL) and National Geodetic Survey (NGS) have developed a new approach based on airborne methods. The new approach yields spatially well distributed high-quality, consistent, and contemporary gravity data. The method to be employed has undergone extensive testing and is now ready for additional investigation. The airborne gravitational data will be used in conjunction with existing ground and marine gravity data sets and data from the Texas Coastal Ocean Observation Network (TCOON), a network of 32 tide gauges, to be used to help identify problems of tying the geoid to mean sea-level. These improved gravity data will lead to the creation of new and improved US geoid models. Accurate geoid models will

  11. A Semi-Analytical Model for Remote Sensing Retrieval of Suspended Sediment Concentration in the Gulf of Bohai, China

    Directory of Open Access Journals (Sweden)

    Jin-Ling Kong

    2015-04-01

    Full Text Available Suspended sediment concentration (SSC is one of the most critical parameters in ocean ecological environment evaluation and it can be determined using ocean color remote sensing (RS. The purpose of this study is to develop a model that provides a reliable and sensitive evaluation of SSC retrieval using RS data. Data were acquired for and gathered from the Gulf of Bohai where SSC levels are relatively low with an average value below 30 mg·L−1. The study indicates that the most sensitive band to SSC levels in the study area is the NIR band of Landsat5 TM images. A quadratic polynomial semi-analytical model appears to be the best retrieval model based on the relationship between the inherent optical properties (IOPs and apparent optical properties (AOPs of water as described by the quasi-analytical algorithm (QAA. The model has a higher precision and effectiveness for SSC retrieval than data-driven statistical models, especially when SSC level is relatively high. The average relative error and the root mean square error (RMSE are 12.32% and 4.53 mg·L−1, respectively, while the correlation coefficient between observed and estimated SSC by the model is 0.95. Using the proposed retrieval model and TM data, SSC levels of the entire study region in the Gulf of Bohai were estimated. These estimates can serve as the baseline for efficient monitoring of the ocean environment in the future.

  12. Meso- and Micro-scale flow modelling in the Gulf of Suez, Arab Republic of Egypt

    DEFF Research Database (Denmark)

    Mortensen, Niels Gylling; Said Said, Usama; Frank, Helmut Paul

    2003-01-01

    The results of a comprehensive, 10-year wind resource assessment programme in the Gulf of Suez are presented. The primary purpose has been to provide reliable and accurate wind atlas data sets for evaluating the potential wind power output from large electricity producing wind-turbine installatio...

  13. Lessons learned using water quality models to develop numeric nutrient criteria for a Gulf coast estuary

    Science.gov (United States)

    Pensacola Bay is a shallow, mesotrophic estuary located in the north-central coast of the Gulf of Mexico, US. In November 2012, the US Environmental Protection Agency (US EPA) proposed numeric total nitrogen (TN), total phosphorus (TP), and chlorophyll-a (chl-a) water quality cr...

  14. Factors influencing the sporulation and cyst formation of Aphanomyces invadans, etiological agent of ulcerative mycosis in Atlantic menhaden, Brevoortia tyrannus

    Science.gov (United States)

    Kiryu, Y.; Blazer, V.S.; Vogelbein, W.K.; Kator, H.; Shields, J.D.

    2005-01-01

    Oomycete infections caused by Aphanomyces invadans occur in freshwater and estuarine fishes around the world. Along the east coast of the USA, skin ulcers caused by A. invadans are prevalent in Atlantic menhaden, Brevoortia tyrannus. From laboratory observations low salinities appear crucial to transmission of the pathogen. To better understand aspects of transmission, we characterized sporulation and cyst formation of secondary zoospores of two isolates of A. invadans at different salinities and temperatures. Sporulation occurred only at low salinities. At room temperature (ca. 20-22 C), using "pond water" augmented with artificial sea salts, the endemic strain WIC and the Thailand strain PA7 of A. invadans produced free-swimming secondary zoospores at salinities of 0, 1 and 2 psu (practical salinity unit = ???), but not at 4 psu or higher. Secondary zoospores of another species, ATCC-62427 (Aphanomyces sp.), were observed at 1, 2, 4 and 8 psu but not at 0 and 12 psu. Secondary zoospores of all three isolates, especially WIC, were abundant and motile 1-2 d post-sporulation. Sporulation was temperature dependent and occurred over a relatively narrow range. No sporulation occurred at 4, 30 or 35 C for either WIC or PA7. For both strains zoospore production within 1-3 d after the initiation of sporulation was more prolific at 25 C than at 20 and 15 C. At 15 C production of zoospores was sustained over 11 d for WIC and 5 d for PA7. At room temperature single WIC secondary zoospores remained motile 12-18 h. Salinities exceeding 4 psu or vigorous shaking caused immediate cyst formation of WIC secondary zoospores. Exposure to menhaden tissue, but not tissues of other fishes to secondary zoospores (WIC), caused rapid (2 h) cyst formation. Cysts were capable of excysting when transferred to 1 psu water within 2-3 h of cyst formation. Cysts that had remained encysted in 6.5 psu for 24 h did not excyst when transferred to 1 psu water. Salinity and temperature requirements

  15. A probabilistic model estimating oil spill clean-up costs--a case study for the Gulf of Finland.

    Science.gov (United States)

    Montewka, Jakub; Weckström, Mia; Kujala, Pentti

    2013-11-15

    Existing models estimating oil spill costs at sea are based on data from the past, and they usually lack a systematic approach. This make them passive, and limits their ability to forecast the effect of the changes in the oil combating fleet or location of a spill on the oil spill costs. In this paper we make an attempt towards the development of a probabilistic and systematic model estimating the costs of clean-up operations for the Gulf of Finland. For this purpose we utilize expert knowledge along with the available data and information from literature. Then, the obtained information is combined into a framework with the use of a Bayesian Belief Networks. Due to lack of data, we validate the model by comparing its results with existing models, with which we found good agreement. We anticipate that the presented model can contribute to the cost-effective oil-combating fleet optimization for the Gulf of Finland. It can also facilitate the accident consequences estimation in the framework of formal safety assessment (FSA).

  16. Toxicity of ozonated estuarine water to juvenile blue crabs (Callinectes sapidus) and Juvenile Atlantic menhaden (Brevoortia tyrannus)

    Energy Technology Data Exchange (ETDEWEB)

    Richardson, L.B.; Burton, D.T.

    1981-02-01

    Large quantitites of estuarine and marine water are treated with chlorine to prevent condenser system fouling at power plants. Chlorine and its residual by-products, however, are toxic to many forms of aquatic life. Ozone is one alternative oxidant which has proven to be an effective biocide and disinfectant in many fresh water applications. Ozonation of estuarine and marine waters, however, may produce residual compounds similar to those produced by chlorination. This study was initiated to provide baseline information on the toxicity of ozonated estuarine water to two representative estuarine species. The blue crab, Callinectes sapidus Rathbun, and the Atlantic menhaden, Brevoortia tyrannus Latrobe, were selected because of their wide distribution and commercial importance. The toxicity of ozone has been compared with chlorine toxicity data from the literature in an effort to examine possible similarities in toxicity.

  17. Modeling coastal aquifers in a Mediterranean area: the example of Taranto gulf (southern Italy)

    Science.gov (United States)

    De Filippis, Giovanna; Giudici, Mauro; Negri, Sergio; Margiotta, Stefano; Cattaneo, Laura; Vassena, Chiara

    2015-04-01

    Water resources stored in coastal aquifers are of strategic relevance for several regions throughout the world and in particular in the Mediterranean basin. They are extremely important in areas characterized by heavy urbanization, active industrial or touristic systems, where the need for fresh water is very acute and, sometimes, they are the only water resources available. This in turn can lead to the phenomenon of seawater intrusion because of aquifer overexploitation to satisfy the demand of an increasing population in coastal plains. Furthermore, karstic aquifers are well known for their specific vulnerability to natural and human-induced contamination, due to their particular characteristics such as thin soils, point recharge in dolines and swallow holes and increased hydraulic conductivity. Within this framework, the Taranto gulf is an example of paramount importance. In fact the presence of a wide industrial area close to the city of Taranto and the numerous maritime and military activities in the harbor area favored the increase of population density in the XX century. Moreover, they constitute factors of great concern for the protection of groundwater quality and quantity, in particular for the presence of the highly-vulnerable basins of Mar Piccolo and Mar Grande. In this area, groundwater resources are stored in a karst multilayered aquifer, which is very complex from the hydrostratigraphic point of view. Furthermore, the presence of highly water-demanding activities makes the seawater intrusion phenomenon very serious, especially along the coastline. In order to characterize the groundwater dynamic in the study area, we discuss the hydraulic relationships between the different hydrostratigraphic units and between the sea and the aquifer system by developing a numerical groundwater model to test and refine the preliminary conceptual model and estimate the most uncertain hydraulic parameters. To achieve these objectives, we used different data-sets to

  18. Geophysical Modeling of Tectonostratigraphic Terrane Boundaries and Crustal Structure Across a Pacific Ocean-Gulf of Mexico Transect, Southern Mexico

    Science.gov (United States)

    Urrutia-Fucugauchi, J.; Flores-Ruiz, J. H.; Spranger, M.

    2006-12-01

    Geophysical models of terrane boundaries and lithospheric structure beneath southern Mexico derived from gravity and aeromagnetic surveys are presented. The transect crosses southern Mexico from the active Pacific margin to the passive Gulf of Mexico margin, across four distinct terranes (Xolapa, Oaxaca, Juarez and Maya) with Precambrian, Paleozoic and Mesozoic basements and contrasting tectonostratigraphic records. The crust/mantle boundary displays a smooth large amplitude variation along the transect from Puerto Escondido at the Pacific margin to Los Tuxtlas-Alvarado at the Gulf of Mexico, roughly between 28 km and 44 km deep. Crustal thickness variations correspond well with inferred terrane distribution and major surface discontinuities. Suture zones are complex as a result of the kinematics of terrane accretion, contrasting crustal rheological properties, shallow level detachments, post-accretion deformation, thermal conditions and characteristics of relative terrane/plate motions. Pre-suturing characteristics of terranes including crustal structure are difficult to document because of deformation resulting from suturing and any subsequent post-accretion processes. In a simplified way, gravity anomalies from the Pacific margin to the Gulf of Mexico show: large positive 50 mgal anomaly above the continental slope units and the intrusive and metamorphic rocks of the Xolapa complex, then anomalies increasingly negative (with minimum values of -180 mgal over the Acatlan and Oaxaca metamorphics. The Juchatengo mylonitic zone is characterized by a gradient change, while minimum gravity values approximately coincide with the wide mylonitic zone north of Oaxaca city. The Juarez terrane and the region over the Sierra de Juarez is characterized by positive gradient. Finally, the Gulf coastal plain is marked by a positive anomaly in the order of -40 mgal. Geophysical models are combined with the seismic models of the Geolimex profile and used to evaluate the crustal

  19. A Hybrid Decision-Making Model for Selecting Container Seaport in the Persian Gulf

    Directory of Open Access Journals (Sweden)

    Jafar Sayareh

    2014-04-01

    Full Text Available Ports have always played a vital role in international transportation. Port selection decision is a process that requires consideration of many important and relevant criteria. The selection of the influential decision-making criteria is also a significant and vital issue which demands cautious thoughts. The main objective of this paper is to weigh the most dominant decision-making criteria by Technique for Order Preference to Similarity by Ideal Solution (TOPSIS and select an optimised container seaport in the Persian Gulf by Analytical Hierarchy Process (AHP according to decisive port selection factors. This paper presents an extensive review of port selection decision-making attributes in different past studies. Finally, by using TOPSIS and AHP, the findings of this research suggest that the working time, stevedoring rate, safety, port entrance, sufficient draft, capacity of port facilities, operating cost, number of berths, ship chandelling, and international policies are critical factors for selecting container seaport in the Persian Gulf.

  20. Gulf of Mexico and Caribbean Sea Data and Model Base Report

    Science.gov (United States)

    1979-07-01

    apparently taking place in the shallower water depths. Although Mexico has deep water reserves, PEMEX is developing the fields under shallow water first...Campeche is presently being explored by 9 rigs, so we can expect about that number of supply boats to b’. operating there at all times. PEMEX is...the northern Gulf of Mexico, and PEMEX is reportedly using 2 in the vicinity of the Bay of Campeche and the periphery of the Yucatan Atoll. With this

  1. The Gulf of Mexico Research Initiative: A Funding Model for Science, Engineering, and Technology

    Science.gov (United States)

    Colwell, R. R.

    2016-12-01

    The Deepwater Horizon oil spill, a massive ecological event, resulted in the tragic loss of 11 lives, and an environmental release of more than 130 million gallons of crude oil. Approximately 1.8 million gallons of dispersants were used in remediation efforts. An immediate response by BP was to establish a ten-year research program, with funding of 500 million. The funding was to determine the impact and long-term ecological and public health effects of oil spills and to develop improved preparation in the event of future oil or gas release into the environment. This Gulf of Mexico Research Initiative (GoMRI), established by BP, provided independent leadership for both the program and administration of the 500 million funding, and the Research Board provides oversight, assisted by excellent staff. The Research Board of the GoMRI comprises twenty scientists, many of whom have prior scientific research administrative expertise. The Research Board, in accordance with its charge, develops research programs and carries out their evaluation and oversight, employing the peer review and operational principles of the National Science Foundation and the National Academies of Science. With these guiding principles, the Research Board established procedures for conflict of interest oversight and requesting and evaluating research programs. It has also focused on communicating the research findings accurately and responsibly. The GoMRI Research Board operates with transparency and ensures availability of all scientific results and data. GoMRI, currently midway through its 10-year mandate, has funded more than 3,000 scientists, representing 278 institutions in 42 states and 17 countries, who have produced more than 1,000 peer-reviewed publications to date. The Research Board is exploring mechanisms by which the GoMRI science findings can be communicated to the broader community and the public and to continue availability of data when the program has ended. A major contribution

  2. Tectonic model and seismic potential of the eastern Gulf of Alaska and Yakataga Seismic Gap

    Science.gov (United States)

    Perez, Omar J.; Jacob, Klaus H.

    1980-12-01

    Based on 13 new fault plane solutions and published seismological, geological, and geophysical data, we interpret the deformation along the Pacific-North American plate margin in the eastern Gulf of Alaska. Three major tectonic units can be distinguished: (1) the North American plate, (2) the Pacific plate, and (3) a belt of mobile borderland terranes. The Pacific plate moves in a NNW direction at rates of about 6 cm/yr in relation to the North American plate. That motion results in mostly right-lateral strike slip at the Queen Charlotte-Fairweather fault system, a well-known observation. A new finding,however, is that a small component (˜1 cm/yr) of convergence may also be present which results in minor subduction of the oceanic plate beneath portions of the continental margin. Heretofore the Queen Charlotte-Fairweather fault zone and associated continental margin was interpreted as a classical, pure transform boundary. The Yakutat block, a borderland terrane about 400 km long and 100 to 200 km wide, is carried passively by the Pacific plate except that the block slowly overrides this plate at about 1 cm/yr. This motion is taken up by almost pure thrust faulting in a southwesterly direction along a 400-km long SE striking shelf edge structure. At its NW edge the Yakutat block is in turn being thrust beneath the North American plate along the Pamplona zone-Icy Bay lineament. The underthrusting of the Yakutat block results in a major orogeny, crustal shortening and uplift of the Chugach-St. Elias range. The effects of this collision may extend as far as 500 km inland and cause some deformation at the Denali fault in the central Alaska Range. Subduction of the Pacific plate beneath the colliding margin appears responsible for development of an active volcanic arc up to 300 km inland which trends SE from the Wrangell Mountains to Yukon Territory, Canada, and perhaps to Mt. Edgecumbe volcano in southeast Alaska. The tectonic model proposed implies a high seismic

  3. A multi-model analysis of the resolution influence on precipitation climatology in the Gulf Stream region

    Science.gov (United States)

    Feng, Xuelei; Huang, Bohua; Kirtman, Ben P.; Kinter, James L.; Chiu, Long S.

    2016-05-01

    Using climate simulations from coupled and uncoupled general circulation models, this study investigates the influence of horizontal resolution in both atmospheric and oceanic model components on the mean precipitation over the Gulf Stream (GS) region. For this purpose, three sets of model experiments are analyzed. The first two examine the effects of increasing horizontal resolution of an atmospheric general circulation model (AGCM) gradually from 100 to 10 km under fixed oceanic settings. Specifically, the AGCM is either forced with prescribed observed sea surface temperature (SST) (the first case) or coupled to a non-eddy-resolving ocean general circulation model (OGCM) at a fixed horizontal resolution near 100 km (the second case). The third set of experiments examines the effects of the oceanic resolution with a pair of long-term simulations by another coupled ocean-atmosphere general circulation model (CGCM), in which the OGCM is run respectively at non-eddy-resolving (100 km) and eddy-resolving (10 km) resolutions, while the AGCM resolution remains fixed at 50 km for both runs. In general, all simulations qualitatively reproduce the gross features of the mean GS precipitation and its annual cycle. At similar AGCM resolutions, the uncoupled models produce a GS rain band that is more realistic in both structure and strength compared to the coupled models with non-eddy-resolving oceans. This is because the prescribed observed SST better represents the gradient near the oceanic front than the non-eddy-resolving OGCMs simulate. An increase from the baseline AGCM resolution produces enhanced climatological GS precipitation, both large-scale and convective, with the latter more tightly confined to the oceanic front. The enhancement, however, is moderate and further increases in resolution achieves diminishing results. On the other hand, an increase in oceanic resolution from non-eddy-resolving to eddy resolving scheme results in more consistent simulations with

  4. Diagnosis of an eddy-resolving Atlantic Ocean model simultation in the vicinity of the Gulf Stream. Part I: Potential voracity

    Science.gov (United States)

    Nakamura, M.; Chao, Y.

    2001-01-01

    Output of an eddy-resolving model of the North Atlantic is diagnosed in the vicinity of the Gulf Stream (GA), using quasigeostrophic potential voracity (QGPV), Ertel's potential voracity (PV), and particle trajectories. Time series of QGPV show strong input of QGPV by the GS in the top 100 m of the model ocean.

  5. Modeling the cost of shut-in production and the value of information in the Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, Mark J.; Pulsipher, Allan G. [Center for Energy Studies, Louisiana State University, Energy Coast and Environment Building, Nicholson Extension Drive, Baton Rouge, LA 70803 (United States)

    2006-03-01

    Weather delay is a common risk in offshore energy production, and in the Gulf of Mexico, the occurrence of tropical storms and hurricanes regularly force operators to shut-down production, cease drilling and construction activities, and evacuate personnel. In physical terms, shutting-in a well will usually not cause a loss of the hydrocarbon resource, but in financial terms, the impact of deferred production can have a significant economic effect. Improved ocean observation systems in the Gulf of Mexico are expected to enhance the reliability and accuracy of hurricane forecasting, lowering the probabilities of false positives, and positively impacting the economic and human life consequences. Improved information reduces risk, and to the extent that operators are risk averse, enhanced information increases welfare. The purpose of this paper is to provide a methodological framework to estimate the cost of shut-in production due to extreme weather, and to provide a first-order lower-bound estimate of the market value of improved weather forecasting. Shut-in production is modeled using various recovery scenarios and valued in terms of the cash flow analysis over the life of the asset. A description of the valuation model and the nature of production recovery is outlined and illustrated through stylized examples. (author)

  6. Particulate accumulations in the vital organs of wild Brevoortia patronus from the northern Gulf of Mexico after the Deepwater Horizon oil spill.

    Science.gov (United States)

    Millemann, Daniel R; Portier, Ralph J; Olson, Gregory; Bentivegna, Carolyn S; Cooper, Keith R

    2015-11-01

    Histopathologic lesions were observed in the commercially important filter-feeding fish, Brevoortia patronus (Gulf menhaden), along the Louisiana Gulf Coast. Menhaden collected from Louisiana waters in 2011 and 2012, 1 and 2 years following the Deepwater Horizon oil spill, showed varying severities of gill lesions as well as an unusual accumulation of black particulates visible at necropsy in the heart and stomach vasculature. The PAH derived particulates were typically 1-4 µm in diameter, but larger aggregates were observed in the coronary vessels on the ventricle surfaces and their location and size was confirmed by light microscopy. Composited particulate composition was consistent with weathered petrogenic polycyclic aromatic hydrocarbon (PAH) mixtures based on GC-MS analysis. Particulates were present in 63 and 80% of fish hearts and 70 and 89% of stomach muscularis collected in 2011 and 2012, respectively. Tissue embedded particulates can lead to localized cellular damage from bioavailable compounds, as well as chronic effects from occlusion of sensitive tissues' blood flow. The PAH derived particulates appeared to act as emboli in small capillaries, and could associated with localized inflammation, focal necrosis and inappropriate collagen and fibroblast tissue repair. We believe large volume filter feeding teleosts, such as menhaden (up to 3 million gallons per year/fish) with high lipid content, have a higher exposure risk and greater potential for toxicity from toxic particulates than other higher trophic level finfish. Suspended PAH derived particulates following an oil spill therefore, should be considered when assessing long-term ecological impacts and not be limited to physical contact (coating) or water soluble fractions for assessing toxicity (gill and neurologic).

  7. Deep Structure and Evolution of the Northeastern Gulf of Aden Margin From Wide-Angle Seismic and Thermomechanical Modeling

    Science.gov (United States)

    Watremez, L.; Leroy, S.; Rouzo, S.; D'Acremont, E.; Burov, E. B.

    2009-12-01

    The Encens survey wide-angle and gravity data (Leroy et al., Feb. March 2006) allow us to determine the deep structure of the northeastern Gulf of Aden non-volcanic passive margin. The Gulf of Aden is a young oceanic basin. Its accretion began at least 17.6 Ma ago. Its current geometry shows 1st and 2nd order segmentation. Our study focus on the second order Ashawq-Salalah segment. We studied six wide-angle seismic (WAS) and gravity profiles (three along and three across the margin). Modeling of the WAS and gravity data gives insights on the first and second orders structures : (1) Continental thinning is abrupt (15-20 km thinning along 50-100 km distance). It is accommodated by four tilted blocks. (2) The OCT is narrow (15 km wide). Its geometry is determined by the velocity models: oceanic-type upper-crust (4.5 km/s) and continental-type lower-crust (> 6.5 km/s). (3) The thickness of the oceanic crust decreases from West (10 km) to East (5.5 km). This pattern is probably linked to a variation of magma supply along the paleo-slow-spreading ridge axis. (4) A 5 km thick intermediate velocity body (7.6 to 7.8 km/s) is present at the crust-mantle interface below the margin. It is interpreted as post-rift underplated, or partly intruded, mafic material. This interpretation is consistent with the presence of a volcano evidenced by heat flow measurement and multichannel seismic reflection (Encens surveys). The studied segment is mainly characterized by abrupt continental thinning and narrow OCT. Moreover, this non-volcanic passive margin is affected by post-rift volcanism evidenced by the mafic body. We then suggest that the evolution of non-volcanic passive margins may be influenced by post-rift thermal anomalies. We will compare these above results with thermomechanical models in order to constrain the margin evolution and factors leading to the Gulf of Aden formation. Modeling is processed using Para(o)voz/Flamar code. This allows us to experiment the influence of

  8. Short-term Influences on Suspended Particulate Matter Distribution in the Northern Gulf of Mexico: Satellite and Model Observations

    Directory of Open Access Journals (Sweden)

    Dong S. Ko

    2008-07-01

    Full Text Available Energetic meteorological events such as frontal passages and hurricanes often impact coastal regions in the northern Gulf of Mexico that influence geochemical processes in the region. Satellite remote sensing data such as winds from QuikSCAT, suspended particulate matter (SPM concentrations derived from SeaWiFS and the outputs (sea level and surface ocean currents of a nested navy coastal ocean model (NCOM were combined to assess the effects of frontal passages between 23-28 March 2005 on the physical properties and the SPM characteristics in the northern Gulf of Mexico. Typical changes in wind speed and direction associated with frontal passages were observed in the latest 12.5 km wind product from QuikSCAT with easterly winds before the frontal passage undergoing systematic shifts in direction and speed and turning northerly, northwesterly during a weak and a strong front on 23 and 27 March, respectively. A quantitative comparison of model sea level results with tide gauge observations suggest better correlations near the delta than in the western part of the Gulf with elevated sea levels along the coast before the frontal passage and a large drop in sea level following the frontal passage on 27 March. Model results of surface currents suggested strong response to wind forcing with westward and onshore currents before the frontal passage reversing into eastward, southeastward direction over a six day period from 23 to 28 March 2005. Surface SPM distribution derived from SeaWiFS ocean color data for two clear days on 23 and 28 March 2005 indicated SPM plumes to be oriented with the current field with increasing concentrations in nearshore waters due to resuspension and discharge from the rivers and bays and its seaward transport following the frontal passage. The backscattering spectral slope γ, a parameter sensitive to particle size distribution also indicated lower γ values (larger particles in nearshore waters that decreased

  9. Hurricane-driven alteration in plankton community size structure in the Gulf of Mexico: A modeling study

    Science.gov (United States)

    Gierach, Michelle M.; Subrahmanyam, Bulusu; Samuelsen, Annette; Ueyoshi, Kyozo

    2009-04-01

    This was the first study to analyze phytoplankton and zooplankton community size structure during hurricane passage. A three-dimensional biophysical model was used to assess ecosystem dynamics, plankton biomass, and plankton distribution in the Gulf of Mexico during Hurricane Katrina (2005). Model simulations revealed that large phytoplankton were most responsive to hurricane-induced turbulent mixing and nutrient injection, with increases in biomass along the hurricane track. Small phytoplankton, microzooplankton, and mesozooplankton biomass primarily shifted in location and increased in spatial extent as a result of Hurricane Katrina. Hurricane passage disrupted the distribution of plankton biomass associated with mesoscale eddies. Biomass minimums and maximums that resided in the center of warm- and cold-core eddies and along eddy peripheries prior to hurricane passage were displaced during Hurricane Katrina.

  10. Climatic change on the Gulf of Fonseca (Central America) using two-step statistical downscaling of CMIP5 model outputs

    Science.gov (United States)

    Ribalaygua, Jaime; Gaitán, Emma; Pórtoles, Javier; Monjo, Robert

    2017-04-01

    A two-step statistical downscaling method has been reviewed and adapted to simulate twenty-first-century climate projections for the Gulf of Fonseca (Central America, Pacific Coast) using Coupled Model Intercomparison Project (CMIP5) climate models. The downscaling methodology is adjusted after looking for good predictor fields for this area (where the geostrophic approximation fails and the real wind fields are the most applicable). The method's performance for daily precipitation and maximum and minimum temperature is analysed and revealed suitable results for all variables. For instance, the method is able to simulate the characteristic cycle of the wet season for this area, which includes a mid-summer drought between two peaks. Future projections show a gradual temperature increase throughout the twenty-first century and a change in the features of the wet season (the first peak and mid-summer rainfall being reduced relative to the second peak, earlier onset of the wet season and a broader second peak).

  11. Lithospheric velocity model of Texas and implications for the Ouachita orogeny and the opening of the Gulf of Mexico

    Science.gov (United States)

    Yao, Yao; Li, Aibing

    2016-12-01

    A 3-D shear wave velocity model of Texas has been developed from Rayleigh wave phase velocities by using ambient noise data recorded at the USArray stations. In the upper crust, the Ouachita front separates high velocity in the Laurentia to its west from low velocity in the east and south Texas basins. The Ouachita belt is characterized as a high-velocity zone with local maximums coinciding with known uplifts, which we interpret as accreted island arcs during the Ouachita orogeny. Our model evidences a strong Ouachita lithosphere that helped to buffer crust thinning from the Mesozoic rifting. A significantly low-velocity anomaly is present in southeast Texas in the lower crust and upper mantle. We associate this anomaly with a past asthenosphere upwelling that likely originated from the edge of the subducted slab during the Ouachita collision and was potentially responsible for the opening of the Gulf of Mexico.

  12. Modelling the cohesive sediment transport in the marine environment: the case of Thermaikos Gulf

    Directory of Open Access Journals (Sweden)

    Y. N. Krestenitis

    2007-01-01

    vertical stratification of the water-column is taken into consideration by appropriate damping of the vertical diffusion term. Variations in cohesive sediment properties during the abidance in the aquatic environment include coagulation and flock break-up processes, quantification of the effects of ambient density to the density of the cohesive aggregate and the associated alterations to the falling speed of the particle. In the vicinity of the seabed, particles may deposit and gradually consolidate with time, the particles remain settled onto the bed, re-enter the flow at a later temporal point or may enter the water column for the first time, originating from the erosion of the bed. The occurrence of each of the aforementioned near-bed processes is defined according to the prevailing benthic shear stress conditions. The mathematical model has been applied to the Thermaikos Gulf, an area of high environmental and socioeconomic importance but also a region of significant pollutant forcing from various anthropogenic activities taking place in the adjoining land. Various kinds of outputs can be extracted, such as trajectories of the overall movement of specific particles and related alterations of their characteristics with time, snapshots of the domain with respect to suspended or deposited matter and natural concentrations of sediments at every required temporal and spatial point. Indicative results from yearly and monthly simulations, using input baroclinic circulation data from the North Aegean Sea model and river discharges are presented and discussed, including outputs from a Typical One-Year Simulation (TOYS, the simulation of the period from 3 September 2001 to 31 August 2002 (S1A2 and the January 2003 experiment (J03. The description of the processes that have been incorporated in the parameterization covers the most significant factors controlling transport and mixing of fine grained sediments in the marine environment, thus validating the accuracy and completeness

  13. Modelling the cohesive sediment transport in the marine environment: the case of Thermaikos Gulf

    Science.gov (United States)

    Krestenitis, Y. N.; Kombiadou, K. D.; Savvidis, Y. G.

    2007-02-01

    taken into consideration by appropriate damping of the vertical diffusion term. Variations in cohesive sediment properties during the abidance in the aquatic environment include coagulation and flock break-up processes, quantification of the effects of ambient density to the density of the cohesive aggregate and the associated alterations to the falling speed of the particle. In the vicinity of the seabed, particles may deposit and gradually consolidate with time, the particles remain settled onto the bed, re-enter the flow at a later temporal point or may enter the water column for the first time, originating from the erosion of the bed. The occurrence of each of the aforementioned near-bed processes is defined according to the prevailing benthic shear stress conditions. The mathematical model has been applied to the Thermaikos Gulf, an area of high environmental and socioeconomic importance but also a region of significant pollutant forcing from various anthropogenic activities taking place in the adjoining land. Various kinds of outputs can be extracted, such as trajectories of the overall movement of specific particles and related alterations of their characteristics with time, snapshots of the domain with respect to suspended or deposited matter and natural concentrations of sediments at every required temporal and spatial point. Indicative results from yearly and monthly simulations, using input baroclinic circulation data from the North Aegean Sea model and river discharges are presented and discussed, including outputs from a Typical One-Year Simulation (TOYS), the simulation of the period from 3 September 2001 to 31 August 2002 (S1A2) and the January 2003 experiment (J03). The description of the processes that have been incorporated in the parameterization covers the most significant factors controlling transport and mixing of fine grained sediments in the marine environment, thus validating the accuracy and completeness of the model. One of the major

  14. Modelling the cohesive sediment transport in the marine environment: the case of Thermaikos Gulf

    Directory of Open Access Journals (Sweden)

    Y. N. Krestenitis

    2006-07-01

    diffusion. The vertical stratification of the water-column is taken into consideration by appropriate damping of the vertical diffusion term. Variations in cohesive sediment properties during the abidance in the aquatic environment include coagulation and flock break-up processes, quantification of the effects of ambient density to the density of the cohesive aggregate and the associated alterations to the falling speed of the particle. In the vicinity of the seabed particles may deposit and gradually consolidate with time, remain settled onto the bed, or renter the flow at a later temporal point. Other particle may enter the water column for the first time, originating from the erosion of the bed. The occurrence of each of the aforementioned near-bed processes is defined accordingly to the prevailing benthic shear stress conditions.

    The mathematical model has been applied to the Thermaikos Gulf, an area of high environmental and socioeconomic importance but also a region of significant pollutant forcing from various anthropogenic activities taking place in the adjoining land. Various kinds of outputs can be extracted, such as trajectories of the overall movement of specific particles and related alterations of their characteristics with time, snapshots of the domain with respect to suspended or deposited matter and naturally concentrations of sediments at every required temporal and spatial point. Indicative results from yearly and monthly simulations, using input baroclinic circulation data from the North Aegean Sea model and river discharges are presented and discussed, including outputs from a Typical One-Year Simulation (TOYS, the simulation of the period from 3 September 2001 to 31 August 2002 (S1A2 and the January 2003 experiment (J03.

    The description of the processes that have been incorporated in the parameterization covers the most significant factors controlling transport and mixing of fine grained sediments in the marine environment, thus

  15. Object location and object recognition memory impairments, motivation deficits and depression in a model of Gulf War illness.

    Science.gov (United States)

    Hattiangady, Bharathi; Mishra, Vikas; Kodali, Maheedhar; Shuai, Bing; Rao, Xiolan; Shetty, Ashok K

    2014-01-01

    Memory and mood deficits are the enduring brain-related symptoms in Gulf War illness (GWI). Both animal model and epidemiological investigations have indicated that these impairments in a majority of GW veterans are linked to exposures to chemicals such as pyridostigmine bromide (PB, an antinerve gas drug), permethrin (PM, an insecticide) and DEET (a mosquito repellant) encountered during the Persian Gulf War-1. Our previous study in a rat model has shown that combined exposures to low doses of GWI-related (GWIR) chemicals PB, PM, and DEET with or without 5-min of restraint stress (a mild stress paradigm) causes hippocampus-dependent spatial memory dysfunction in a water maze test (WMT) and increased depressive-like behavior in a forced swim test (FST). In this study, using a larger cohort of rats exposed to GWIR-chemicals and stress, we investigated whether the memory deficiency identified earlier in a WMT is reproducible with an alternative and stress free hippocampus-dependent memory test such as the object location test (OLT). We also ascertained the possible co-existence of hippocampus-independent memory dysfunction using a novel object recognition test (NORT), and alterations in mood function with additional tests for motivation and depression. Our results provide new evidence that exposure to low doses of GWIR-chemicals and mild stress for 4 weeks causes deficits in hippocampus-dependent object location memory and perirhinal cortex-dependent novel object recognition memory. An open field test performed prior to other behavioral analyses revealed that memory impairments were not associated with increased anxiety or deficits in general motor ability. However, behavioral tests for mood function such as a voluntary physical exercise paradigm and a novelty suppressed feeding test (NSFT) demonstrated decreased motivation levels and depression. Thus, exposure to GWIR-chemicals and stress causes both hippocampus-dependent and hippocampus-independent memory

  16. Simulation and performance Analysis of a Novel Model for Short Range Underwater Acoustic communication Channel Using Ray Tracing Method in Turbulent Shallow Water Regions of the Persian Gulf

    Directory of Open Access Journals (Sweden)

    Mohammad Javad Dargahi

    2011-01-01

    Full Text Available High data rate acoustic transmission is required for diverse underwater operations such as the retrieval of large amounts of data from bottom packages and real time transmission of signals from underwater sensors. The major obstacle to underwater acoustic communication is the interference of multipath signals due to surface and bottom reflections. High speed acoustic transmission over a shallow water channel characterized by small grazing angles presents formidable difficulties. The reflection losses associated with such small angles are low, causing large amplitudes in multi-path signals. In this paper, based on the results obtained from practical measurements in the Persian Gulf and available data about sound speed variations in different depths, we propose a simple but effective model for shallow water short-range multipath acoustic channel. Based on the Ray theory, mathematical modeling of multipath effects is carried out. Also in channel modeling, the attenuation due to the wave scatterings at the surface and its bottom reflections for deferent grazing angles and bottom types is considered. In addition, we consider the attenuations due to the absorption of different materials and ambient noises such as see-state noise, shipping noise, thermal noise and turbulences. We use a three-dimensional hydrodynamic model (COHERENS in a fully prognostic mode to study the circulation and water mass properties of the Persian Gulf - a large inverse estuary. Maximum sound speed occurs during the summer in the Persian Gulf which decreases gradually moving from the Strait of Hormuz to the north western part of the Gulf. A gradual decrease in sound speed profiles with depth was commonly observed in almost all parts of the Gulf. However, an exception occurred in the Strait of Hormuz during the winter. The results of the model are in very good agreement with our observations.

  17. Menhaden oil, but not safflower or soybean oil, aids in restoring the polyunsaturated fatty acid profile in the novel delta-6-desaturase null mouse

    Directory of Open Access Journals (Sweden)

    Monteiro Jessica

    2012-05-01

    Full Text Available Abstract Background Polyunsaturated fatty acids (PUFA have diverse biological effects, from promoting inflammation to preventing cancer and heart disease. Growing evidence suggests that individual PUFA may have independent effects in health and disease. The individual roles of the two essential PUFA, linoleic acid (LA and α-linolenic acid (ALA, have been difficult to discern from the actions of their highly unsaturated fatty acid (HUFA downstream metabolites. This issue has recently been addressed through the development of the Δ-6 desaturase knock out (D6KO mouse, which lacks the rate limiting Δ-6 desaturase enzyme and therefore cannot metabolize LA or ALA. However, a potential confounder in this model is the production of novel Δ-5 desaturase (D5D derived fatty acids when D6KO mice are fed diets containing LA and ALA, but void of arachidonic acid. Objective The aim of the present study was to characterize how the D6KO model differentially responds to diets containing the essential n-6 and n-3 PUFA, and whether the direct provision of downstream HUFA can rescue the phenotype and prevent the production of D5D fatty acids. Methodology Liver and serum phospholipid (PL fatty acid composition was examined in D6KO and wild type mice fed i 10% safflower oil diet (SF, LA rich ii 10% soy diet (SO, LA+ALA or iii 3% menhaden oil +7% SF diet (MD, HUFA rich for 28 days (n = 3-7/group. Results Novel D5D fatty acids were found in liver PL of D6KO fed SF or SO-fed mice, but differed in the type of D5D fatty acid depending on diet. Conversely, MD-fed D6KO mice had a liver PL fatty acid profile similar to wild-type mice. Conclusions Through careful consideration of the dietary fatty acid composition, and especially the HUFA content in order to prevent the synthesis of D5D fatty acids, the D6KO model has the potential to elucidate the independent biological and health effects of the parent n-6 and n-3 fatty acids, LA and ALA.

  18. Object Location and Object Recognition Memory Impairments, Motivation Deficits and Depression in a Model of Gulf War Illness

    Directory of Open Access Journals (Sweden)

    Bharathi eHattiangady

    2014-03-01

    Full Text Available Memory and mood deficits are the enduring brain-related symptoms in Gulf War illness (GWI. Both animal model and epidemiological investigations have indicated that these impairments in a majority of GW veterans are linked to exposures to chemicals such as pyridostigmine bromide (PB, an anti nerve gas drug, permethrin (PM, an insecticide and DEET (a mosquito repellant encountered during the Persian Gulf War-1. Our previous study in a rat model has shown that combined exposures to low doses of GWI-related (GWIR chemicals PB, PM and DEET with or without 5-minutes of restraint stress (a mild stress paradigm causes hippocampus-dependent spatial memory dysfunction in a water maze test and increased depressive-like behavior in a forced swim test. In this study, using a larger cohort of rats exposed to GWIR-chemicals and stress, we investigated whether the memory deficiency identified earlier in a water maze test is reproducible with an alternative and stress free hippocampus-dependent memory test such as the object location test. We also ascertained the possible co-existence of hippocampus-independent memory dysfunction using a novel object recognition test, and alterations in mood function with additional tests for motivation and depression. Our results provide new evidence that exposure to low doses of GWIR-chemicals and stress for four weeks causes deficits in hippocampus-dependent object location memory and perirhinal cortex-dependent novel object recognition memory. An open field test performed prior to other behavioral analyses revealed that memory impairments were not associated with increased anxiety or deficits in general motor ability. However, behavioral tests for mood function such as a voluntary physical exercise paradigm and a novelty suppressed feeding test showed decreased motivation and depression. Thus, exposure to GWIR-chemicals and stress causes both hippocampus-dependent and hippocampus-independent memory impairments as well as

  19. A Data-Assimilative Modeling System for the Gulf of Alaska based on the Regional Ocean Modeling System (ROMS)

    Science.gov (United States)

    Farrara, J.; Chao, Y.; Li, Z.; Wang, X.; Jin, X.; Li, P.

    2010-12-01

    A ROMS-based data-assimilative modeling system for the Gulf of Alaska (GoA) has been developed. A three-level, nested ROMS configuration is used: the largest level (L0) covers an extended region of the GoA at a horizontal resolution of 9km; the next level (L1) is nested in L0 and covers the northern GoA at a horizontal resolution of 3km; the last level (L2) is nested in L1 and focuses on the region around the Prince William Sound at a horizontal resolution of 1km. The system is forced at the ocean surface by output from regional and global atmospheric models and by freshwater runoff from land obtained via real-time execution of a digital elevation model forced by air temperature and precipitation data from the regional and global atmospheric models.. In-situ and satellite measurements are assimilated using a multi-scale 3-dimensional variational (MS-3DVAR) data assimilation scheme. In addition, parallel real-time runs of the system coupled with the COSINE ecosystem model have been performed. The performance of the system has recently been evaluated using data gathered during the Sound Predictions field experiment held in the Prince William Sound (PWS) region during summer 2009. During the experiment, the system was run daily in near real-time. Nowcasts were produced every 6 hours and a 48-hr forecast was run once per day.The overall flow pattern within the PWS as revealed by HF radar surface current observations and surface drifters was realistically reproduced by the ROMS model. In addition, a comparison of the model temperature and salinity profiles with those gathered by ship CTD, glider and Remus AUV show overall excellent agreement. For the temperature, the overall bias was found to be small (-0.12C) and the RMS difference was also reasonably small (0.83C) with good agreement across all temperatures (depths) sampled. For the salinity, there was good agreement at the higher salinities (larger depths), but there was a salty bias at lower salinities (shallower

  20. A high-resolution hydrodynamic-biogeochemical coupled model of the Gulf of Cadiz – Alboran Sea region.

    Directory of Open Access Journals (Sweden)

    D. M. MACIAS

    2014-12-01

    Full Text Available The southern Iberia regional seas comprise the Gulf of Cadiz and the Alboran Sea sub-basins connected by the narrow Strait of Gibraltar. Both basins are very different in their hydrological and biological characteristics but are, also, tightly connected to each other. Integrative studies of the whole regional oceanic system are scarce and difficult to perform due to the relative large area to cover and the different relevant time-scales of the main forcings in each sub-basin. Here we propose, for the first time, a fully coupled, 3D, hydrodynamic-biogeochemical model that covers, in a single domain (~2km resolution both marine basins for a 20 years simulation (1989-2008. Model performance is assessed against available data in terms of spatial and temporal distributions of biological variables. In general, the proposed model is able to represent the climatological distributions of primary and secondary producers and also the main seasonality of primary production in the different sub-regions of the analyzed basins. Potential causes of the observed mismatches between model and data are identified and some solutions are proposed for future model development. We conclude that most of these mismatches could be attributed to the missing tidal forcing in the actual model configuration. This model is a first step to obtain a meaningful tool to study past and future oceanographic conditions in this important marine region constituting the unique connection of the Mediterranean Sea with the open world’s ocean.

  1. A high-resolution hydrodynamic-biogeochemical coupled model of the Gulf of Cadiz – Alboran Sea region.

    Directory of Open Access Journals (Sweden)

    D. M. MACIAS

    2015-01-01

    Full Text Available The southern Iberia regional seas comprise the Gulf of Cadiz and the Alboran Sea sub-basins connected by the narrow Strait of Gibraltar. Both basins are very different in their hydrological and biological characteristics but are, also, tightly connected to each other. Integrative studies of the whole regional oceanic system are scarce and difficult to perform due to the relative large area to cover and the different relevant time-scales of the main forcings in each sub-basin. Here we propose, for the first time, a fully coupled, 3D, hydrodynamic-biogeochemical model that covers, in a single domain (~2km resolution both marine basins for a 20 years simulation (1989-2008. Model performance is assessed against available data in terms of spatial and temporal distributions of biological variables. In general, the proposed model is able to represent the climatological distributions of primary and secondary producers and also the main seasonality of primary production in the different sub-regions of the analyzed basins. Potential causes of the observed mismatches between model and data are identified and some solutions are proposed for future model development. We conclude that most of these mismatches could be attributed to the missing tidal forcing in the actual model configuration. This model is a first step to obtain a meaningful tool to study past and future oceanographic conditions in this important marine region constituting the unique connection of the Mediterranean Sea with the open world’s ocean.

  2. Comparison of Sea Surface Heights Derived from the Navy Coastal Ocean Model With Satellite Altimetry in the Gulf of Mexico

    Science.gov (United States)

    2008-01-01

    The Gulf of Mexico (GOM) is a semi-enclosed sea that connects in the east to the Atlantic ocean through the straits of Florida, and in the south to...the Caribbean Sea, the Gulf of Mexico , the Straits of Florida, and parts of the western North Atlantic Ocean is the real-time ocean nowcast/forecast

  3. Modeling petroleum generation and geochemistry of crude oils in Ras Budran field, northern gulf of Suez, Egypt: implications for prospectivity

    Energy Technology Data Exchange (ETDEWEB)

    Younes, M.A. [Geology Dept., Alexandria Univ. (Egypt)

    2005-12-01

    Petroleum generation modeling of the pre-rift succession in Ras Budran Field, which is located in the northern Gulf of Suez province in Egypt, showed that the best oil prone source rocks identified are the carbonate dominated one in the Upper Cretaceous and the Middle Eocene. These source rocks contain type-II kerogen (liptinitic materials) and progressively increase in their peak of oil generation from 0.63 and 0.83 vitrinite reflectance at a depth of about 3000 meters during the early of middle Miocene age and could have charged traps during the intra Rudeis tectonic phase. Crude oil and source rock extract interrelationships display a great similarity in their geologic occurrences and biological marker distributions. The biomarker characteristics indicate a low relative abundance of oleanane index around 5% pristane/phytane ratio<1, higher C{sub 35}/C{sub 34} homohopanes>1 and higher gammacerane indices >30%, suggesting a typical marine organic matter with source rock deposition under reducing conditions, Marginally mature stage of oil generation is indicated by the relatively low sterane isomerization of C{sub 29} {alpha}{alpha}{alpha} 20S/(S+R) and C{sub 29}{alpha}{beta}{beta}/({alpha}{beta}{beta}+{alpha}{alpha}{alpha}) of about 06 and relatively low aromatic sulfur compound rations. Crude oil geochemistry and related source rock potential define genetically related oils which ware generated from marginally mature and organic-rich carbonate source rocks, most probably from the pre-rift Duwi and Thebes formations. The best oil prone for future prospectivity would be oriented west of Ras Budran Field toward the deep marine of the Gulf, where the undiscovered reserves are expected to be accumulated within the pre-rift reservoirs in the footwalls of the normal faulted blocks. (orig.)

  4. Preliminary Source Characterization and Tsunami Modeling of Submarine Landslides along the Yucatan Shelf/Campeche Escarpment, southern Gulf of Mexico

    Science.gov (United States)

    Chaytor, J. D.; Geist, E. L.; Paull, C. K.; Caress, D. W.; Gwiazda, R.; Fucugauchi, J. U.; Rebolledo-Vieyra, M.

    2014-12-01

    Using high-resolution multibeam bathymetry recently collected by the R/V Falkor, we evaluated the morphology, size, and tsunami-generating potential of a number of large, previously unknown, submarine landslides that excavated sections of the submerged Yucatan Shelf/carbonate platform above the Campeche Escarpment. Landslide evacuations appear to be primarily restricted to the later Cenozoic sections of the margin, removing pelagic sediments deposited above the Cretaceous shallow water carbonates exposed along the face of the escarpment. The largest landslides have evacuated areas of the shelf between 130 and 1,100 km2, possibly removing as much as 70 km3 of material in a single event. Based on the morphology of the evacuated areas, the primary mode of failure appears to be translational and retrogressive, with slide thickness primarily stratigraphically controlled. Displaced material appears to be present within some of the evacuation zones, but because sediments from the Mississippi Fan onlap the base of the Campeche Escarpment, mass-transport deposits from individual landslides have not been identified and therefore run-outs are poorly constrained. The evacuation zones are used to specify the initial conditions for tsunami modeling. Both regional, Gulf of Mexico and near-field simulations are performed to determine the severity and wave-height distribution for six slide scenarios. Preliminary results indicate that the location of maximum wave heights associated with the slide scenarios depend on the direction on down-slope slide movement, although there are significant refraction effects during basin-wide propagation. There is also significant energy dissipation during cross-shelf propagation, with wider shelves lessening the severity of tsunami runup compared to runup at coastal locations adjacent to narrower shelves. Future tsunami hazard assessments in the Gulf of Mexico should account for these large, newly discovered submarine landslides.

  5. Parvalbumin and neuropeptide Y expressing hippocampal GABA-ergic inhibitory interneuron numbers decline in a model of Gulf War illness.

    Science.gov (United States)

    Megahed, Tarick; Hattiangady, Bharathi; Shuai, Bing; Shetty, Ashok K

    2014-01-01

    Cognitive dysfunction is amongst the most conspicuous symptoms in Gulf War illness (GWI). Combined exposure to the nerve gas antidote pyridostigmine bromide (PB), pesticides and stress during the Persian Gulf War-1 (PGW-1) are presumed to be among the major causes of GWI. Indeed, our recent studies in rat models have shown that exposure to GWI-related (GWIR) chemicals and mild stress for 4 weeks engenders cognitive impairments accompanied with several detrimental changes in the hippocampus. In this study, we tested whether reduced numbers of hippocampal gamma-amino butyric acid (GABA)-ergic interneurons are among the pathological changes induced by GWIR-chemicals and stress. Animals were exposed to low doses of GWIR-chemicals and mild stress for 4 weeks. Three months after this exposure, subpopulations of GABA-ergic interneurons expressing the calcium binding protein parvalbumin (PV), the neuropeptide Y (NPY) and somatostatin (SS) in the hippocampus were stereologically quantified. Animals exposed to GWIR-chemicals and stress for 4 weeks displayed reduced numbers of PV-expressing GABA-ergic interneurons in the dentate gyrus and NPY-expressing interneurons in the CA1 and CA3 subfields. However, no changes in SS+ interneuron population were observed in the hippocampus. Furthermore, GABA-ergic interneuron deficiency in these animals was associated with greatly diminished hippocampus neurogenesis. Because PV+ and NPY+ interneurons play roles in maintaining normal cognitive function and neurogenesis, and controlling the activity of excitatory neurons in the hippocampus, reduced numbers of these interneurons may be one of the major causes of cognitive dysfunction and reduced neurogenesis observed in GWI. Hence, strategies that improve inhibitory neurotransmission in the hippocampus may prove beneficial for reversing cognitive dysfunction in GWI.

  6. Parvalbumin and Neuropeptide Y Expressing Hippocampal GABA-ergic Inhibitory Interneuron Numbers Decline in a Model of Gulf War illness

    Directory of Open Access Journals (Sweden)

    Tarick eMegahed

    2015-01-01

    Full Text Available Cognitive dysfunction is amongst the most conspicuous symptoms in Gulf war illness (GWI. Combined exposure to the nerve gas antidote pyridostigmine bromide, pesticides and stress during the Persian Gulf War-1 are presumed to be among the major causes of GWI. Indeed, our recent studies in rat models have shown that exposure to GWI-related (GWIR chemicals and mild stress for four weeks engenders cognitive impairments accompanied with several detrimental changes in the hippocampus. In this study, we tested whether reduced numbers of hippocampal gamma-amino butyric acid (GABA-ergic interneurons are among the pathological changes induced by GWIR-chemicals and stress. Animals were exposed to low doses of GWIR-chemicals and mild stress for four weeks. Three months after this exposure, subpopulations of GABA-ergic interneurons expressing the calcium binding protein parvalbumin (PV, the neuropeptide Y (NPY and somatostatin (SS in the hippocampus were stereologically quantified. Animals exposed to GWIR-chemicals and stress for four weeks displayed reduced numbers of PV-expressing GABA-ergic interneurons in the dentate gyrus and NPY-expressing interneurons in the CA1 and CA3 subfields. However, no changes in SS+ interneuron population were observed in the hippocampus. Furthermore, GABA-ergic interneuron deficiency in these animals was associated with greatly diminished hippocampus neurogenesis. Because PV+ and NPY+ interneurons play roles in maintaining normal cognitive function and neurogenesis, and controlling the activity of excitatory neurons in the hippocampus, reduced numbers of these interneurons may be one of the major causes of cognitive dysfunction and reduced neurogenesis observed in GWI. Hence, strategies that improve inhibitory neurotransmission in the hippocampus may prove beneficial for reversing cognitive dysfunction in GWI.

  7. Lithostratigraphy and lithofacies analysis of the Fahliyan/Garau formations in the Persian Gulf with an application in petroleum system modelling

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Salehi

    2016-09-01

    Full Text Available The Lower Cretaceous Fahliyan Formation is one of important hydrocarbon reservoirs in the Persian Gulf and neighboring Arabian countries. Lithologically, this formation is mainly composed of limestone, argillaceous limestone and dolomite. Three major units have been recognized in the Fahliyan Formation (i.e. Lower, Middle and Upper Fahliyan which are respectively equivalent to the Sulaiy, Yamama and Ratawi formations in the Arabian countries of southern Persian Gulf. To the northwest of Persian Gulf the Fahliyan Formation interfingers with the Garau Formation. The Fahliyan Formation is considered as time equivalent to some part of the Garau Formation, and is recognized as a source rocks in northwestern part of the Persian Gulf. Analysis of available geology and petrophysical data of the key wells penetrated through the Fahliyan and its equivalent Garau formations led to the recognition of 21 facies that were deposited in three sub-environments (belts: inner, middle and outer carbonate platform and also an intrashelf settings. The observed lithofacies pattern in the study area indicate a homoclinal carbonate ramp as the depositional environment for the Fahliyan Formation. Based on the recognized facies within the Fahliyan Formation the spatial distribution pattern of reservoir, source and seal rocks are presented in all the stratigraphic units in order to use a more accurate facies map for the petroleum system modelling.

  8. Model estimates of the impact of bioirrigation activity of MARENZELLERIA spp. on the trophic state of the Gulf of Finland ecosystem

    Science.gov (United States)

    Isaev, Alexey; Eremina, Tatjana; Savchuk, Oleg; Ryabchenko, Vladimir

    2016-04-01

    Since the end of the 2000s, a sparcely populated soft bottom area in the deeps of the Eastern Gulf of Finland has been affected by invasive species Marenzelleria spp. The burrow flushing of sediments by Marenzelleria results in deeper penetration of oxygen into the sediments with corresponding redox alterations of nutrient cycling. In oxic conditions, a lager fraction of mineralized phosphates is transformed into particulate form due to formation of iron-humate complexes, thus increasing sediment phosphorus retention and burial. On the contrary, increased oxygen availability reduces nitrogen removal by denitrification, thus leading to larger release of nitrate into the water column. Indeed, as was revealed by long-term observations, the large-scale invasion of Marenzelleria spp. into the Eastern Gulf of Finland was accompanied by significant increase of the N:P ratio (Maximov et al., 2014). For a quantitative assessment of the bioirrigation activity of Marenzelleria spp., sediment parameterizations in SPBEM (St. Petersburg Baltic eutrophication model) have been modified as follows. Intensified burrow flushing is considered as the enlarged water-sediment contact area between water and sediments and described with the coefficient of bioirrigation determined by the abundance of polychaete and radius of their burrows. These parameterizations have been applied for simulation of the Gulf of Finland nutrient dynamics during 2010-2040. Preliminary results of simulations showed that vital activity of invasive Marenzelleria spp. might lead to slowdown or decrease of eutrophication in the Gulf of Finland due to reduction of cyanobacterial blooms

  9. Assimilation of Altimeter Data into a Quasigeostrophic Model of the Gulf Stream System. Part 2; Assimilation Results

    Science.gov (United States)

    Capotondi, Antonietta; Holland, William R.; Malanotte-Rizzoli, Paola

    1995-01-01

    The improvement in the climatological behavior of a numerical model as a consequence of the assimilation of surface data is investigated. The model used for this study is a quasigeostrophic (QG) model of the Gulf Stream region. The data that have been assimilated are maps of sea surface height that have been obtained as the superposition of sea surface height variability deduced from the Geosat altimeter measurements and a mean field constructed from historical hydrographic data. The method used for assimilating the data is the nudging technique. Nudging has been implemented in such a way as to achieve a high degree of convergence of the surface model fields toward the observations. Comparisons of the assimilation results with available in situ observations show a significant improvement in the degree of realism of the climatological model behavior, with respect to the model in which no data are assimilated. The remaining discrepancies in the model mean circulation seem to be mainly associated with deficiencies in the mean component of the surface data that are assimilated. On the other hand, the possibility of building into the model more realistic eddy characteristics through the assimilation of the surface eddy field proves very successful in driving components of the mean model circulation that are in relatively good agreement with the available observations. Comparisons with current meter time series during a time period partially overlapping the Geosat mission show that the model is able to 'correctly' extrapolate the instantaneous surface eddy signals to depths of approximately 1500 m. The correlation coefficient between current meter and model time series varies from values close to 0.7 in the top 1500 m to values as low as 0.1-0.2 in the deep ocean.

  10. Gulf War

    DEFF Research Database (Denmark)

    Dalgaard-Nielsen, Anja

    2003-01-01

    As it became a non‐permanent member of the UN Security Council in January 2003, Germany stepped up its opposition to war with Iraq. The stage was set for a repeat of Germany's uncomfortable position during the 1991 Gulf War. At that time, as most of Germany's allies rallied behind Washington......, Germany made only financial contributions, and hundreds of thousands of Germans took to the streets to protest against the war. Yet, since 1991, Germany had come a long way in its attitudes towards military force. From a policy of complete abstention from military deployments beyond NATO's area (so...

  11. Data collection for cooperative water resources modeling in the Lower Rio Grande Basin, Fort Quitman to the Gulf of Mexico.

    Energy Technology Data Exchange (ETDEWEB)

    Passell, Howard David; Pallachula, Kiran (GRAM, Inc., Albuquerque, NM); Tidwell, Vincent Carroll; Villalobos, Joshua (Texas A& M University); Piccinni, Giovanni (Texas A& M University); Brainard, James Robert; Gerik, Thomas (Texas A& M University); Morrison, Wendy (Texas A& M University); Serrat-Capdevila, Aleix (University of Arizona); Valdes, Juan (University of Arizona); Sheng, Zhuping (Texas A& M University); Lovato, Rene (Instituto Mexicano de Tecnologia del Agua); Guitron, Alberto (Instituto Mexicano de Tecnologia del Agua); Ennis, Martha Lee; Aparicio, Javier (Instituto Mexicano de Tecnologia del Agua); Newman, Gretchen Carr (GRAM, Inc., Albuquerque, NM); Michelsen, Ari M. (Texas A& M University)

    2004-10-01

    Water resource scarcity around the world is driving the need for the development of simulation models that can assist in water resources management. Transboundary water resources are receiving special attention because of the potential for conflict over scarce shared water resources. The Rio Grande/Rio Bravo along the U.S./Mexican border is an example of a scarce, transboundary water resource over which conflict has already begun. The data collection and modeling effort described in this report aims at developing methods for international collaboration, data collection, data integration and modeling for simulating geographically large and diverse international watersheds, with a special focus on the Rio Grande/Rio Bravo. This report describes the basin, and the data collected. This data collection effort was spatially aggregated across five reaches consisting of Fort Quitman to Presidio, the Rio Conchos, Presidio to Amistad Dam, Amistad Dam to Falcon Dam, and Falcon Dam to the Gulf of Mexico. This report represents a nine-month effort made in FY04, during which time the model was not completed.

  12. Mesoscale variability in the Arabian Sea from HYCOM model results and observations: impact on the Persian Gulf Water path

    Science.gov (United States)

    L'Hégaret, P.; Duarte, R.; Carton, X.; Vic, C.; Ciani, D.; Baraille, R.; Corréard, S.

    2015-09-01

    The Arabian Sea and Sea of Oman circulation and water masses, subject to monsoon forcing, reveal a strong seasonal variability and intense mesoscale features. We describe and analyze this variability and these features, using both meteorological data (from ECMWF reanalyses), in situ observations (from the ARGO float program and the GDEM - Generalized Digital Environmental mode - climatology), satellite altimetry (from AVISO) and a regional simulation with a primitive equation model (HYCOM - the Hybrid Coordinate Ocean Model). The model and observations display comparable variability, and the model is then used to analyze the three-dimensional structure of eddies and water masses with higher temporal and spatial resolutions than the available observations. The mesoscale features are highly seasonal, with the formation of coastal currents, destabilizing into eddies, or the radiation of Rossby waves from the Indian coast. The mesoscale eddies have a deep dynamical influence and strongly drive the water masses at depth. In particular, in the Sea of Oman, the Persian Gulf Water presents several offshore ejection sites and a complex recirculation, depending on the mesoscale eddies. The associated mechanisms range from coastal ejection via dipoles, alongshore pulses due to a cyclonic eddy, to the formation of lee eddies downstream of Ra's Al Hamra. This water mass is also captured inside the eddies via several mechanisms, keeping high thermohaline characteristics in the Arabian Sea. The variations of the outflow characteristics near the Strait of Hormuz are compared with variations downstream.

  13. Myxosporean plasmodial infection associated with ulcerative lesions in young-of-the-year Atlantic menhaden in a tributary of the Chesapeake Bay, and possible links to Kudoa clupeidae

    Science.gov (United States)

    Reimschuessel, R.; Gieseker, C.M.; Driscoll, C.; Baya, A.; Kane, A.S.; Blazer, V.S.; Evans, J.J.; Kent, M.L.; Moran, J.D.W.; Poynton, S.L.

    2003-01-01

    Ulcers in Atlantic menhaden Brevoortia tyrannus (Latrobe) (Clupeidae), observed along the USA east coast, have been attributed to diverse etiologies including bacterial, fungal and, recently, harmful algal blooms. To understand the early pathogenesis of these lesions, we examined juvenile Atlantic menhaden collected during their seasonal presence in Chesapeake Bay tributaries from April to October 1999 and from March to August 2000. We conducted histopathological examinations of young-of-the-year fish from the Pocomoke River tributary, which has a history of fish mortalities and high lesion prevalence. Kudoa clupeidae (Myxozoa: Myxosporea) spores were present in the muscles of fish collected in both years. Of the fish assessed by histology in April, 5 to 14% were infected, while in May 90 to 96% were infected. Infection rates remained high during the summer. Mature spores were primarily located within myomeres and caused little or no observable pathological changes. Ultrastructure showed spores with capsulogenic cells bearing filamentous projections, and a basal crescentic nucleus with mottled nucleoplasm containing cleaved, condensed chromatin. Also, a highly invasive plasmodial stage of a myxozoan was found in the lesions of juvenile Atlantic menhaden. The plasmodia were observed in fish collected between May and July, with the maximum occurrence in late June 1999 and late May 2000. Plasmodia penetrated and surrounded muscle bundles, causing grossly observable raised lesions in 73% of all fish infected with this invasive stage. Plasmodia were also detected in the visceral organs, branchial arches, and interocular muscles of some fish. Some of the invasive extrasporogonic plasmodial lesions were associated with ulcers and chronic inflammatory infiltrates. The plasmodial stage appeared to slough out of the tissue with subsequent evidence of wound healing. Ultrastructure showed plasmodia with an elaborate irregular surface, divided into distinct ectoplasm and

  14. Analysis of the ecosystem structure of Laguna Alvarado, western Gulf of Mexico, by means of a mass balance model

    Science.gov (United States)

    Cruz-Escalona, V. H.; Arreguín-Sánchez, F.; Zetina-Rejón, M.

    2007-03-01

    Alvarado is one of the most productive estuary-lagoon systems in the Mexican Gulf of Mexico. It has great economic and ecological importance due to high fisheries productivity and because it serves as a nursery, feeding, and reproduction area for numerous populations of fishes and crustaceans. Because of this, extensive studies have focused on biology, ecology, fisheries (e.g. shrimp, oysters) and other biological components of the system during the last few decades. This study presents a mass-balanced trophic model for Laguna Alvarado to determine it's structure and functional form, and to compare it with similar coastal systems of the Gulf of Mexico and Mexican Pacific coast. The model, based on the software Ecopath with Ecosim, consists of eighteen fish groups, seven invertebrate groups, and one group each of sharks and rays, marine mammals, phytoplankton, sea grasses and detritus. The acceptability of the model is indicated by the pedigree index (0.5) which range from 0 to 1 based on the quality of input data. The highest trophic level was 3.6 for marine mammals and snappers. Total system throughput reached 2680 t km -2 year -1, of which total consumption made up 47%, respiratory flows made up 37% and flows to detritus made up 16%. The total system production was higher than consumption, and net primary production higher than respiration. The mean transfer efficiency was 13.8%. The mean trophic level of the catch was 2.3 and the primary production required to sustain the catch was estimated in 31 t km -2 yr -1. Ecosystem overhead was 2.4 times the ascendancy. Results suggest a balance between primary production and consumption. In contrast with other Mexican coastal lagoons, Laguna Alvarado differs strongly in relation to the primary source of energy; here the primary producers (seagrasses) are more important than detritus pathways. This fact can be interpreted a response to mangrove deforest, overfishing, etc. Future work might include the compilation of

  15. Measurement of Rayleigh wave Z/H ratio and joint inversion for a high-resolution S wave velocity model beneath the Gulf of Mexico passive margin

    Science.gov (United States)

    Miao, W.; Li, G.; Niu, F.

    2016-12-01

    Knowledge on the 3D sediment structure beneath the Gulf of Mexico passive margin is not only important to explore the oil and gas resources in the area, but also essential to decipher the deep crust and mantle structure beneath the margin with teleseismic data. In this study, we conduct a joint inversion of Rayleigh wave ellipticity and phase velocity at 6-40 s to construct a 3-D S wave velocity model in a rectangular area of 100°-87° west and 28°-37° north. We use ambient noise data from a total of 215 stations of the Transportable Array deployed under the Earthscope project. Rayleigh wave ellipticity, or Rayleigh wave Z/H (vertical to horizontal) amplitude ratio is mostly sensitive to shallow sediment structure, while the dispersion data are expected to have reasonably good resolution to uppermost mantle depths. The Z/H ratios measured from stations inside the Gulf Coastal Plain are distinctly lower in comparison with those measured from the inland stations. We also measured the phase velocity dispersion from the same ambient noise dataset. Our preliminary 3-D model is featured by strong low-velocity anomalies at shallow depth, which are spatially well correlated with Gulf Cost, East Texas, and the Lower Mississippi basins. We will discuss other features of the 3-D models once the model is finalized.

  16. Eutrophication-induced acidification of coastal waters in the northern Gulf of Mexico: Insights into origin and processes from a coupled physical-biogeochemical model

    Science.gov (United States)

    Laurent, Arnaud; Fennel, Katja; Cai, Wei-Jun; Huang, Wei-Jen; Barbero, Leticia; Wanninkhof, Rik

    2017-01-01

    Nutrient inputs from the Mississippi/Atchafalaya River system into the northern Gulf of Mexico promote high phytoplankton production and lead to high respiration rates. Respiration coupled with water column stratification results in seasonal summer hypoxia in bottom waters on the shelf. In addition to consuming oxygen, respiration produces carbon dioxide (CO2), thus lowering the pH and acidifying bottom waters. Here we present a high-resolution biogeochemical model simulating this eutrophication-driven acidification and investigate the dominant underlying processes. The model shows the recurring development of an extended area of acidified bottom waters in summer on the northern Gulf of Mexico shelf that coincides with hypoxic waters. Not reported before, acidified waters are confined to a thin bottom boundary layer where the production of CO2 by benthic metabolic processes is dominant. Despite a reduced saturation state, acidified waters remain supersaturated with respect to aragonite.

  17. Refining the model of barrier island formation along a paraglacial coast in the Gulf of Maine

    Science.gov (United States)

    Hein, Christopher J.; FitzGerald, Duncan M.; Carruthers, Emily A.; Stone, Byron D.; Barnhardt, Walter A.; Gontz, Allen M.

    2012-01-01

    Details of the internal architecture and local geochronology of Plum Island, the longest barrier in the Gulf of Maine, have refined our understanding of barrier island formation in paraglacial settings. Ground-penetrating radar and shallow-seismic profiles coupled with sediment cores and radiocarbon dates provide an 8000-year evolutionary history of this barrier system in response to changes in sediment sources and supply rates as well as variability in the rate of sea-level change. The barrier sequence overlies tills of Wisconsinan and Illinoian glaciations as well as late Pleistocene glaciomarine clay deposited during the post-glacial sea-level highstand at approximately 17 ka. Holocene sediment began accumulating at the site of Plum Island at 7–8 ka, in the form of coarse fluvial channel-lag deposits related to the 50-m wide erosional channel of the Parker River that carved into underlying glaciomarine deposits during a lower stand of sea level. Plum Island had first developed in its modern location by ca. 3.6 ka through onshore migration and vertical accretion of reworked regressive and lowstand deposits. The prevalence of southerly, seaward-dipping layers indicates that greater than 60% of the barrier lithosome developed in its modern location through southerly spit progradation, consistent with a dominantly longshore transport system driven by northeast storms. Thinner sequences of northerly, landward-dipping clinoforms represent the northern recurve of the prograding spit. A 5–6-m-thick inlet-fill sequence was identified overlying the lower stand fluvial deposit; its stratigraphy captures events of channel migration, ebb-delta breaching, onshore bar migration, channel shoaling and inlet infilling associated with the migration and eventual closure of the inlet. This inlet had a maximum cross-sectional area of 2800 m2 and was active around 3.5–3.6 ka. Discovery of this inlet suggests that the tidal prism was once larger than at present. Bay infilling

  18. Membrane physical properties do not explain increased cyclic AMP production in hepatocytes from rats fed menhaden oil.

    Science.gov (United States)

    Bizeau, M E; Hazel, J R

    2000-06-01

    To study the effect of altering plasma membrane fatty acid composition on the glucagon signal transduction pathway, cAMP accumulation was measured in hepatocytes from rats fed diets containing either menhaden oil (MO) or coconut oil (CO). Hepatocytes from MO-fed animals produced significantly more cAMP in response to glucagon and forskolin compared to CO-fed animals. Glucagon receptor number and affinity were similar in MO- and CO-fed rats. Liver plasma membranes from MO-fed animals were enriched in long-chain n-3 fatty acids and contained significantly lower amounts of saturated C10-C16 and 18:1n-9 than CO-fed animals. Membrane physical properties were examined using both Fourier transform infrared spectroscopy (FTIR) and the fluorescent probe 1,6-diphenyl-1,3,5-hexatriene (DPH). FTIR analysis revealed that below 34 degrees C, CO membranes were more ordered than MO membranes. However, as assay temperature approached 37 degrees C, MO and CO membranes became similarly ordered. DPH polarization values indicated no differences in membrane order at 37 degrees C, whereas membrane order was decreased in CO-fed animals at 25 degrees C. These data indicate the importance of assay temperature in assessing the influence of membrane physical properties on the activity of signal transduction pathways. Whereas increased signal transduction activity has been correlated to reduced membrane order in MO-fed animals, these data indicate that at physiological temperatures membrane order did not vary between groups. Enhanced cAMP accumulation in response to forskolin indicates that adenylate cyclase activity or content may be elevated in MO- vs. CO-fed rats. Enhanced adenylate cyclase activity may result, in part, from changes in specific fatty acids in hepatocyte plasma membranes without demonstrable changes in membrane physical properties.

  19. Shallow Water Dynamics in the Arabian Gulf and Gulf of Oman

    Science.gov (United States)

    2016-06-07

    Shallow Water Dynamics in the Arabian Gulf and Gulf of Oman Dr. Cheryl Ann Blain Naval Research Laboratory, Ocean Dynamics and Prediction Branch...of a circulation model for the Arabian Gulf and connecting waters that realistically predicts the complex, 3-D circulation and mixing patterns in the...forcings in the region, a strong evaporative flux, seasonal wind forcing, and freshwater river discharge. Not only are realistic current fields sought but

  20. Modelling surface drifting of buoys during a rapidly-moving weather front in the Gulf of Finland, Baltic Sea

    Science.gov (United States)

    Gästgifvars, Maria; Lauri, Hannu; Sarkanen, Annakaisa; Myrberg, Kai; Andrejev, Oleg; Ambjörn, Cecilia

    2006-12-01

    The Gulf of Finland is an elongated estuary located in the north-eastern extremity of the Baltic Sea. This semi-enclosed sea-area is subject to heavy sea traffic, and is one of the main risk areas for oil accidents in the Baltic. The continuous development and validation of operational particle drift and oil-spill forecasting systems is thus seen to be essential for this sea-area. Here, the results of a three-day drift experiment in May 2003 are discussed. The field studies were performed using GPS-positioned surface floating buoys. The aim of this paper is to evaluate how well models can reproduce the drift of these buoys. Model simulations, both in forecast and hindcast modes, were carried out by three different 3D hydrodynamic models, the results of which are evaluated by comparing the calculated drifts with observations. These models were forced by HIRLAM (High Resolution Limited Area Model) and ECMWF (European Centre for Medium-Range Weather Forecasts) meteorological forecast fields. The simulated drift of the buoys showed a good agreement with observations even when, during the study period, a rapidly-changing wind situation was observed to affect the investigation area; in this situation the winds turned about 100 degrees in half an hour. In such a case it is a very complicated task to forecast the drifters' routes: there is a need to regularly update the meteorological forcing fields and to use these regularly-updated fields throughout the simulations. It is furthermore recommended that forecasts should be made using several circulation models and several meteorological forecasts, in order to get an overview of the accuracy of the forecasted drifts and related differences in between the forecasts.

  1. Assimilation of Altimeter Data into a Quasigeostrophic Model of the Gulf Stream System. Part 1; Dynamical Considerations

    Science.gov (United States)

    Capotondi, Antonietta; Malanotte-Rizzoli, Paola; Holland, William R.

    1995-01-01

    The dynamical consequences of constraining a numerical model with sea surface height data have been investigated. The model used for this study is a quasigeostrophic model of the Gulf Stream region. The data that have been assimilated are maps of sea surface height obtained as the superposition of sea surface height variability deduced from the Geosat altimeter measurements and a mean field constructed from historical hydrographic data. The method used for assimilating the data is the nudging technique. Nudging has been implemented in such a way as to achieve a high degree of convergence of the surface model fields toward the observations. The assimilation of the surface data is thus equivalent to the prescription of a surface pressure boundary condition. The authors analyzed the mechanisms of the model adjustment and the characteristics of the resultant equilibrium state when the surface data are assimilated. Since the surface data are the superposition of a mean component and an eddy component, in order to understand the relative role of these two components in determining the characteristics of the final equilibrium state, two different experiments have been considered: in the first experiment only the climatological mean field is assimilated, while in the second experiment the total surface streamfunction field (mean plus eddies) has been used. It is shown that the model behavior in the presence of the surface data constraint can be conveniently described in terms of baroclinic Fofonoff modes. The prescribed mean component of the surface data acts as a 'surface topography' in this problem. Its presence determines a distortion of the geostrophic contours in the subsurface layers, thus constraining the mean circulation in those layers. The intensity of the mean flow is determined by the inflow/outflow conditions at the open boundaries, as well as by eddy forcing and dissipation.

  2. Multiple regression models of δ13C and δ15N for fish populations in the eastern Gulf of Mexico

    Science.gov (United States)

    Radabaugh, Kara R.; Peebles, Ernst B.

    2014-08-01

    Multiple regression models were created to explain spatial and temporal variation in the δ13C and δ15N values of fish populations on the West Florida Shelf (eastern Gulf of Mexico, USA). Extensive trawl surveys from three time periods were used to acquire muscle samples from seven groundfish species. Isotopic variation (δ13Cvar and δ15Nvar) was calculated as the deviation from the isotopic mean of each fish species. Static spatial data and dynamic water quality parameters were used to create models predicting δ13Cvar and δ15Nvar in three fish species that were caught in the summers of 2009 and 2010. Additional data sets were then used to determine the accuracy of the models for predicting isotopic variation (1) in a different time period (fall 2010) and (2) among four entirely different fish species that were collected during summer 2009. The δ15Nvar model was relatively stable and could be applied to different time periods and species with similar accuracy (mean absolute errors 0.31-0.33‰). The δ13Cvar model had a lower predictive capability and mean absolute errors ranged from 0.42 to 0.48‰. δ15N trends are likely linked to gradients in nitrogen fixation and Mississippi River influence on the West Florida Shelf, while δ13C trends may be linked to changes in algal species, photosynthetic fractionation, and abundance of benthic vs. planktonic basal resources. These models of isotopic variability may be useful for future stable isotope investigations of trophic level, basal resource use, and animal migration on the West Florida Shelf.

  3. Stratigraphy of two conjugate margins (Gulf of Lion and West Sardinia): modeling of vertical movements and sediment budgets

    Science.gov (United States)

    Leroux, Estelle; Gorini, Christian; Aslanian, Daniel; Rabineau, Marina; Blanpied, Christian; Rubino, Jean-Loup; Robin, Cécile; Granjeon, Didier; Taillepierre, Rachel

    2016-04-01

    The post-rift (~20-0 Ma) vertical movements of the Provence Basin (West Mediterranean) are quantified on its both conjugate (the Gulf of Lion and the West Sardinia) margins. This work is based on the stratigraphic study of sedimentary markers using a large 3D grid of seismic data, correlations with existing drillings and refraction data. The post-rift subsidence is measured by the direct use of sedimentary geometries analysed in 3D [Gorini et al., 2015; Rabineau et al., 2014] and validated by numerical stratigraphic modelling. Three domains were found: on the platform (1) and slope (2), the subsidence takes the form of a seaward tilting with different amplitudes, whereas the deep basin (3) subsides purely vertically [Leroux et al., 2015a]. These domains correspond to the deeper crustal domains respectively highlighted by wide angle seismic data. The continental crust (1) and the thinned continental crust (2) are tilted, whereas the intermediate crust, identified as lower continental exhumed crust [Moulin et al., 2015, Afhilado et al., 2015] (3) sagged. The post-break-up subsidence re-uses the initial hinge lines of the rifting phase. This striking correlation between surface geologic processes and deep earth dynamic processes emphasizes that the sedimentary record and sedimentary markers is a window into deep geodynamic processes and dynamic topography. Pliocene-Pleistocene seismic markers enabled high resolution quantification of sediment budgets over the past 6 Myr [Leroux et al., in press]. Sediment budget history is here completed on the Miocene interval. Thus, the controlling factors (climate, tectonics and eustasy) are discussed. Afilhado, A., Moulin, M., Aslanian, D., Schnürle, P., Klingelhoefer, F., Nouzé, H., Rabineau, M., Leroux, E. & Beslier, M.-O. (2015). Deep crustal structure across a young 1 passive margin from wide-angle and reflection seismic data (The SARDINIA Experiment) - II. Sardinia's margin. Bull. Soc. géol. France, 186, ILP Spec. issue, 4

  4. Model estimates of the impact of bioirrigation activity of Marenzelleria spp. on the Gulf of Finland ecosystem in a changing climate

    Science.gov (United States)

    Isaev, A. V.; Eremina, T. R.; Ryabchenko, V. A.; Savchuk, O. P.

    2017-07-01

    Drastic changes have occurred in the Eastern Gulf of Finland ecosystem after recent invasion and establishment of polychaete Marenzelleria spp. Possible mechanisms of these changes are explored with the help of three-dimensional ecosystem model SPBEM. Relative significance of bioirrigation activity is studied by comparison of two climate change scenario simulations, which include or disregard Marenzelleria effects. The novel results obtained with this approach demonstrate that on a system level biogeochemical consequences of both implemented climate changes scenario and polychaete activity are equivalent to a weakening of ;vicious circle; of the Baltic Sea eutrophication. The eutrophication-mitigating effects of the Marenzelleria invasion into the Eastern Gulf of Finland, revealed by the long-term field measurements, are explained by simulation-based considerations.

  5. Improving seismic crustal models in the Corinth Gulf, Greece and estimating source depth using PL-waves

    Science.gov (United States)

    Vackář, Jiří; Zahradník, Jiří

    2013-04-01

    A recent shallow earthquake in the Corinth Gulf, Greece (Mw 5.3, January 18, 2010; Sokos et al., Tectonophysics 2012) generated unusual long-period waves (periods > 5 seconds), well recorded at several near-regional stations between the P - and S-wave arrival. The 5-second period, being significantly longer than the source duration, indicates a structural effect. The wave is similar to PL-wave or Pnl-wave, but with shorter periods and observed in much closer distances (ranging from 30 to 200 km). For theoretical description of the observed wave, structural model is required. No existing regional crustal model generates that wave, so we need to find another model, better in terms of the PL-wave existence and strength. We find such models by full waveform inversion using the subset of stations with strong PL-wave. The Discrete Wavenumber method (Bouchon, 1981; Coutant 1989) is used for forward problem and the Neighborhood Algorithm (Sambridge, 1999) for stochastic search (more details in poster by V. Plicka and J. Zahradník). We obtain a suite of models well fitting synthetic seismograms and use some of these models to evaluate dependence of the studied waves on receiver distance and azimuth as well as dependence on source depth. We compare real and synthetic dispersion curves (derived from synthetic seismograms) as an independent validation of found model and discuss limitations of using dispersion curves for these cases. We also relocated the event in the new model. Then we calculate the wavefield by two other methods: modal summation and ray theory to better understand the nature of the PL-wave. Finally, we discuss agreement of found models with published crustal models in the region. The full waveform inversion for structural parameters seems to be powerful tool for improving seismic source modeling in cases we do not have accurate structure model of studied area. We also show that the PL-wave strength has a potential to precise the earthquake depth

  6. Altered gut microbiome in a mouse model of Gulf War Illness causes neuroinflammation and intestinal injury via leaky gut and TLR4 activation.

    Science.gov (United States)

    Alhasson, Firas; Das, Suvarthi; Seth, Ratanesh; Dattaroy, Diptadip; Chandrashekaran, Varun; Ryan, Caitlin N; Chan, Luisa S; Testerman, Traci; Burch, James; Hofseth, Lorne J; Horner, Ronnie; Nagarkatti, Mitzi; Nagarkatti, Prakash; Lasley, Stephen M; Chatterjee, Saurabh

    2017-01-01

    Many of the symptoms of Gulf War Illness (GWI) that include neurological abnormalities, neuroinflammation, chronic fatigue and gastrointestinal disturbances have been traced to Gulf War chemical exposure. Though the association and subsequent evidences are strong, the mechanisms that connect exposure to intestinal and neurological abnormalities remain unclear. Using an established rodent model of Gulf War Illness, we show that chemical exposure caused significant dysbiosis in the gut that included increased abundance of phylum Firmicutes and Tenericutes, and decreased abundance of Bacteroidetes. Several gram negative bacterial genera were enriched in the GWI-model that included Allobaculum sp. Altered microbiome caused significant decrease in tight junction protein Occludin with a concomitant increase in Claudin-2, a signature of a leaky gut. Resultant leaching of gut caused portal endotoxemia that led to upregulation of toll like receptor 4 (TLR4) activation in the small intestine and the brain. TLR4 knock out mice and mice that had gut decontamination showed significant decrease in tyrosine nitration and inflammatory mediators IL1β and MCP-1 in both the small intestine and frontal cortex. These events signified that gut dysbiosis with simultaneous leaky gut and systemic endotoxemia-induced TLR4 activation contributes to GW chemical-induced neuroinflammation and gastrointestinal disturbances.

  7. Altered gut microbiome in a mouse model of Gulf War Illness causes neuroinflammation and intestinal injury via leaky gut and TLR4 activation

    Science.gov (United States)

    Dattaroy, Diptadip; Chandrashekaran, Varun; Ryan, Caitlin N.; Chan, Luisa S.; Testerman, Traci; Burch, James; Hofseth, Lorne J.; Horner, Ronnie; Nagarkatti, Mitzi; Nagarkatti, Prakash; Lasley, Stephen M.; Chatterjee, Saurabh

    2017-01-01

    Many of the symptoms of Gulf War Illness (GWI) that include neurological abnormalities, neuroinflammation, chronic fatigue and gastrointestinal disturbances have been traced to Gulf War chemical exposure. Though the association and subsequent evidences are strong, the mechanisms that connect exposure to intestinal and neurological abnormalities remain unclear. Using an established rodent model of Gulf War Illness, we show that chemical exposure caused significant dysbiosis in the gut that included increased abundance of phylum Firmicutes and Tenericutes, and decreased abundance of Bacteroidetes. Several gram negative bacterial genera were enriched in the GWI-model that included Allobaculum sp. Altered microbiome caused significant decrease in tight junction protein Occludin with a concomitant increase in Claudin-2, a signature of a leaky gut. Resultant leaching of gut caused portal endotoxemia that led to upregulation of toll like receptor 4 (TLR4) activation in the small intestine and the brain. TLR4 knock out mice and mice that had gut decontamination showed significant decrease in tyrosine nitration and inflammatory mediators IL1β and MCP-1 in both the small intestine and frontal cortex. These events signified that gut dysbiosis with simultaneous leaky gut and systemic endotoxemia-induced TLR4 activation contributes to GW chemical-induced neuroinflammation and gastrointestinal disturbances. PMID:28328972

  8. Mixing heights and surface fluxes over Galveston Bay and the Gulf of Mexico: Implications for modeling of pollution episodes

    Science.gov (United States)

    Angevine, W. M.; Tucker, S. C.; Fairall, C.; Bariteau, L.; Wolfe, D.; Zagar, M.; Brewer, A.

    2007-12-01

    During the 2006 Texas Air Quality Study, boundary layer measurements were made by in-situ instruments, lidars, and rawinsondes on the NOAA RV Ronald H. Brown as well as by radar wind profilers on land. Brown also carried instruments to measure surface heat and momentum fluxes. This presentation will emphasize measurements made in Galveston Bay and in the Gulf of Mexico near the Houston area. Details of boundary layer depth and turbulence intensity over these waters have not been well known previously, but are quite important to the understanding of high ozone episodes in Houston. One somewhat surprising result is that the boundary layer over water was almost always slightly unstable, with positive surface heat flux. Mixing depths were moderate, although mixing was generally weak compared to that over land. Boundary layer heights over the water were substantially shallower than daytime heights over land. Experiments in modeling ozone episodes with WRF at 1.5-km grid spacing will be shown and compared with the measurements.

  9. Improved reservoir modelling with time-lapse seismic data in a Gulf of Mexico gas condensate reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Waggoner, J.R.; Seymour, R.H.; Cominelli, A. [ENI/Agip Div., Milan (Italy); Stradiotti, A. [Agip Petroleum, Houston, TX (United States)

    2003-07-01

    Time-lapse 3D- or 4D-seismic data have been tried in several fields to date, with some good case studies published to demonstrate the utility of the 4D seismic information. While another 4D case study would be useful, this paper describes two novel aspects of a recent application in the Gulf of Mexico. First, the target reservoir contains a gas condensate fluid under primary depletion, so pressure, rather than saturation, changes create the observed 4D acoustic response. Further, the primary impact of the pressure change is to the fluid composition as the initially dense gas phase lightens as condensate drops out below the dew point. The result was a 2.8% change in acoustic impedance predicted in the feasibility study. Second, the 4D seismic result was used to constrain an optimized history-matching procedure, along with the production data. After describing the method used, the paper will discuss the changes to the reservoir model that resulted. While the results should not be considered unique, they do give some insight into the structure of the reservoir that should be considered for optimal reservoir management. (Author)

  10. Improvements of Storm Surge Modelling in the Gulf of Venice with Satellite Data: The ESA Due Esurge-Venice Project

    Science.gov (United States)

    De Biasio, F.; Bajo, M.; Vignudelli, S.; Papa, A.; della Valle, A.; Umgiesser, G.; Donlon, C.; Zecchetto, S.

    2016-08-01

    Among the most detrimental natural phenomena, storm surges heavily endanger the environment, the economy and the everyday life of sea-side countries and coastal zones. Considering that 120.000.000 people live in the Mediterranean area, with additional 200.000.000 presences in Summer for tourism purposes, the correct prediction of storm surges is crucial to avoid fatalities and economic losses. Earth Observation (EO) can play an important role in operational storm surge forecasting, yet it is not widely diffused in the storm surge community. In 2011 the European Space Agency (ESA), through its Data User Element (DUE) programme, financed two projects aimed at encouraging the uptake of EO data in this sector: eSurge and eSurge-Venice (eSV). The former was intended to address the issues of a wider users' community, while the latter was focused on a restricted geographical area: the northern Adriatic Sea and the Gulf of Venice. Among the objectives of the two projects there were a number of storm surge hindcast experiments using satellite data, to demonstrate the improvements on the surge forecast brought by EO. We report here the results of the hindcast experiments of the eSV project. They were aimed to test the sensitivity of a storm surge model to a forcing wind field modified with scatterometer data in order to reduce the bias between simulated and observed winds. Hindcast experiments were also performed to test the response of the storm surge model to the assimilation, with a dual 4D-Var system, of satellite altimetry observations as model errors of the initial state of the sea surface level. Remarkable improvements on the storm surge forecast have been obtained for what concerns the modified model wind forcing. Encouraging results have been obtained also in the assimilation experiments.

  11. Alterations in benzo(A)pyrene metabolism and in vivo binding to hepatic DNA in rats red diets containing menhaden oil

    Energy Technology Data Exchange (ETDEWEB)

    Wade, A.E.; Dharwadkar, S.

    1987-01-01

    Polyunsaturated fatty acids of the omega-6 type have been shown to support the mixed function oxidases (MFO) responsible for carcinogen activation and to promote tumorigenesis in laboratory animals. The omega-3 fatty acids contained in menhaden oil (MO) have been shown to enhance MFO activity and increase the binding of Benzo(a)pyrene (B(a)P) metabolites to calf thymus DNA in an in vitro microsomal system. Rats fed two levels of MO (0.5% and 20%) for 11 days received a single i.p. dose of (/sup 3/H)B(a)P (5 m Ci/kg) dissolved in DMSO. At selected time intervals thereafter rats were killed, blood withdrawn, livers removed and DNA extracted. Hepatic microsomes were recovered from control rats on each diet at the time of B(a)P administration to assess MFO activities. Binding of B(a)P to DNA was higher in rats fed the 20% MO diet suggesting an increased rate of B(a)P activation. Blood levels of B(a)P were elevated at 16 and 24 hours post B(a)P, however no differences in urine concentrations were observed. Elevations in concentration of cytochrome P-450, ethoxycoumarin dealkylase, and glutathione S-transferase suggest that omega-3 fatty acids of menhaden fish oil support MFO related reactions not unlike the omega-6 fatty acids.

  12. Chemical and histological comparisons between Brevoortia sp. (menhaden) collected in fall 2010 from Barataria Bay, LA and Delaware Bay, NJ following the DeepWater Horizon (DWH) oil spill.

    Science.gov (United States)

    Bentivegna, Carolyn S; Cooper, Keith R; Olson, Gregory; Pena, Edwin A; Millemann, Daniel R; Portier, Ralph J

    2015-12-01

    Body burdens of PAHs were compared to histological effects in menhaden (Family: Clupeidae, Genus: Brevoortia) collected in fall 2010 from Barataria Bay, LA (BBLA) and Delaware Bay, NJ (DBNJ). Barataria Bay was heavily oiled during the DeepWater Horizon (DWH) oil spill, while Delaware Bay although urbanized had no reported recent oil spills. GCMS analyses of pre-spill 2009, BBLA and DBNJ fish found predominantly C2/C3 phenanthrene (1.28-6.52 ng/mg). However, BBLA also contained five higher molecular weight PAHs (0.06-0.34 ng/mg DW). Fluorescent aromatic compound spectroscopy (FACS) of gastrointestinal (GI) tract tissue showed statistically higher levels of hydroxypyrene-like PAHs in DBNJ than BBLA fish. Histopathologic lesions were more prevalent in BBLA than DBNJ fish. The lesion prevalence (gill, trunk kidney, epidermis, stomach) in the BBLA menhaden were significantly higher and more severe than observed in the DBNJ menhaden. Reversible lesions included gill lamellar hyperplasia, adhesions, edema, and epidermal hyperplasia. The increased pigmented macrophage centers were indicative of activated macrophages responding to connective tissue damage or other antigens. The liver hepatic necrosis and renal tissue mineralization may well have undergone repair, but damage to the kidney nephrons and hepatic/biliary regions of the liver would be slower to resolve and apparently remained after elimination of PAHs. Therefore, a direct cause and effect between DWH oil spill and increased lesion prevalence in BBLA menhaden could not be established.

  13. Performance evaluation of ocean color satellite models for deriving accurate chlorophyll estimates in the Gulf of Saint Lawrence

    Directory of Open Access Journals (Sweden)

    M. Montes-Hugo

    2014-06-01

    Full Text Available The understanding of phytoplankton dynamics in the Gulf of the Saint Lawrence (GSL is critical for managing major fisheries off the Canadian East coast. In this study, the accuracy of two atmospheric correction techniques (NASA standard algorithm, SA, and Kuchinke's spectral optimization, KU and three ocean color inversion models (Carder's empirical for SeaWiFS (Sea-viewing Wide Field-of-View Sensor, EC, Lee's quasi-analytical, QAA, and Garver- Siegel-Maritorena semi-empirical, GSM for estimating the phytoplankton absorption coefficient at 443 nm (aph(443 and the chlorophyll concentration (chl in the GSL is examined. Each model was validated based on SeaWiFS images and shipboard measurements obtained during May of 2000 and April 2001. In general, aph(443 estimates derived from coupling KU and QAA models presented the smallest differences with respect to in situ determinations as measured by High Pressure liquid Chromatography measurements (median absolute bias per cruise up to 0.005, RMSE up to 0.013. A change on the inversion approach used for estimating aph(443 values produced up to 43.4% increase on prediction error as inferred from the median relative bias per cruise. Likewise, the impact of applying different atmospheric correction schemes was secondary and represented an additive error of up to 24.3%. By using SeaDAS (SeaWiFS Data Analysis System default values for the optical cross section of phytoplankton (i.e., aph(443 = aph(443/chl = 0.056 m2mg−1, the median relative bias of our chl estimates as derived from the most accurate spaceborne aph(443 retrievals and with respect to in situ determinations increased up to 29%.

  14. Observation and modeling of the seismic seiches triggered in the Gulf of Corinth (Greece) by the 2011 Mw 9.0 Tohoku earthquake

    Science.gov (United States)

    Canitano, Alexandre; Bernard, Pascal; Allgeyer, Sébastien

    2017-09-01

    The study reports an unusual water level rise in the Gulf of Corinth, central Greece, during the passing of the seismic waves of the remote 2011 Mw 9.0 Tohoku earthquake. The seismic seiches were recorded by a tide-gauge located in the marina of the island of Trizonia, in the western side of the gulf. The cross-analysis between the ground motion and the water level changes shows that seiching was initiated by the arrival of the earlier S-waves and then enhanced by the surface waves. The seiching concerns five domains with periods ranging from minute to about 7 min and with water level changes of a few millimeters to a few centimeters. The main seiching period is about 5-7 min and the related water level has a maximum trough-to-peak amplitude of about 6-8 cm. Numerical simulation of the seismic seiches, based on the shallow water equations, allows us to model reasonably well the amplitude of the seiches for most of the period domains, excepted those for the main seiching period at 7 min, which are underestimated by a factor of about 2-3. The largest bathymetric structures of the gulf to be excited in a seiche mode, with eigenperiods of hundreds of seconds, are a few kilometers in size.

  15. Estuary/ocean exchange and tidal mixing in a Gulf of Maine Estuary: A Lagrangian modeling study

    Science.gov (United States)

    Bilgili, Ata; Proehl, Jeffrey A.; Lynch, Daniel R.; Smith, Keston W.; Swift, M. Robinson

    2005-12-01

    A Lagrangian particle method embedded within a 2-D finite element code, is used to study the transport and ocean-estuary exchange processes in the well-mixed Great Bay Estuarine System in New Hampshire, USA. The 2-D finite element model, driven by residual, semi-diurnal and diurnal tidal constituents, includes the effects of wetting and drying of estuarine mud flats through the use of a porous medium transport module. The particle method includes tidal advection, plus a random walk model in the horizontal that simulates sub-grid scale turbulent transport processes. Our approach involves instantaneous, massive [O(500,000)] particle releases that enable the quantification of ocean-estuary and inter-bay exchanges in a Markovian framework. The effects of the release time, spring-neap cycle, riverine discharge and diffusion strength on the intra-estuary and estuary-ocean exchange are also investigated. The results show a rather dynamic interaction between the ocean and the estuary with a fraction of the exiting particles being caught up in the Gulf of Maine Coastal Current and swept away. Three somewhat different estimates of estuarine residence time are calculated to provide complementary views of estuary flushing. Maps of residence time versus release location uncover a strong spatial dependency of residence time within the estuary that has very important ramifications for local water quality. Simulations with and without the turbulent random walk show that the combined effect of advective shear and turbulent diffusion is very effective at spreading particles throughout the estuary relatively quickly, even at low (1 m 2/s) diffusivity. The results presented here show that a first-order Markov Chain approach has applicability and a high potential for improving our understanding of the mixing processes in estuaries.

  16. Parametric Adjustments to the Rankine Vortex Wind Model for Gulf of Mexico Hurricanes

    Science.gov (United States)

    2012-11-01

    Rankine Vortex (RV) model [25], the SLOSH model [28], the Holland model [29], the vortex simulation model [30], and the Willoughby and Rahn model [31...www.asme.org/terms/Terms_Use.cfm where Pn ¼ Pc 20:69 þ 1:33Vm þ 0:11u (3) Willoughby et al. [34] provide an alternative formula to estimate Rm as a function of...MacAfee and Pearson [26], and Willoughby et al. [34] also made adjustments which were tailored for mid- latitude applications. 3 Adjustments to the RV

  17. Modeled Sea Level Rise Impacts on Coastal Ecosystems at Six Major Estuaries on Florida's Gulf Coast: Implications for Adaptation Planning.

    Science.gov (United States)

    Geselbracht, Laura L; Freeman, Kathleen; Birch, Anne P; Brenner, Jorge; Gordon, Doria R

    2015-01-01

    The Sea Level Affecting Marshes Model (SLAMM) was applied at six major estuaries along Florida's Gulf Coast (Pensacola Bay, St. Andrews/Choctawhatchee Bays, Apalachicola Bay, Southern Big Bend, Tampa Bay and Charlotte Harbor) to provide quantitative and spatial information on how coastal ecosystems may change with sea level rise (SLR) and to identify how this information can be used to inform adaption planning. High resolution LiDAR-derived elevation data was utilized under three SLR scenarios: 0.7 m, 1 m and 2 m through the year 2100 and uncertainty analyses were conducted on selected input parameters at three sites. Results indicate that the extent, spatial orientation and relative composition of coastal ecosystems at the study areas may substantially change with SLR. Under the 1 m SLR scenario, total predicted impacts for all study areas indicate that coastal forest (-69,308 ha; -18%), undeveloped dry land (-28,444 ha; -2%) and tidal flat (-25,556 ha; -47%) will likely face the greatest loss in cover by the year 2100. The largest potential gains in cover were predicted for saltmarsh (+32,922 ha; +88%), transitional saltmarsh (+23,645 ha; na) and mangrove forest (+12,583 ha; +40%). The Charlotte Harbor and Tampa Bay study areas were predicted to experience the greatest net loss in coastal wetlands The uncertainty analyses revealed low to moderate changes in results when some numerical SLAMM input parameters were varied highlighting the value of collecting long-term sedimentation, accretion and erosion data to improve SLAMM precision. The changes predicted by SLAMM will affect exposure of adjacent human communities to coastal hazards and ecosystem functions potentially resulting in impacts to property values, infrastructure investment and insurance rates. The results and process presented here can be used as a guide for communities vulnerable to SLR to identify and prioritize adaptation strategies that slow and/or accommodate the changes underway.

  18. Modeled Sea Level Rise Impacts on Coastal Ecosystems at Six Major Estuaries on Florida's Gulf Coast: Implications for Adaptation Planning.

    Directory of Open Access Journals (Sweden)

    Laura L Geselbracht

    Full Text Available The Sea Level Affecting Marshes Model (SLAMM was applied at six major estuaries along Florida's Gulf Coast (Pensacola Bay, St. Andrews/Choctawhatchee Bays, Apalachicola Bay, Southern Big Bend, Tampa Bay and Charlotte Harbor to provide quantitative and spatial information on how coastal ecosystems may change with sea level rise (SLR and to identify how this information can be used to inform adaption planning. High resolution LiDAR-derived elevation data was utilized under three SLR scenarios: 0.7 m, 1 m and 2 m through the year 2100 and uncertainty analyses were conducted on selected input parameters at three sites. Results indicate that the extent, spatial orientation and relative composition of coastal ecosystems at the study areas may substantially change with SLR. Under the 1 m SLR scenario, total predicted impacts for all study areas indicate that coastal forest (-69,308 ha; -18%, undeveloped dry land (-28,444 ha; -2% and tidal flat (-25,556 ha; -47% will likely face the greatest loss in cover by the year 2100. The largest potential gains in cover were predicted for saltmarsh (+32,922 ha; +88%, transitional saltmarsh (+23,645 ha; na and mangrove forest (+12,583 ha; +40%. The Charlotte Harbor and Tampa Bay study areas were predicted to experience the greatest net loss in coastal wetlands The uncertainty analyses revealed low to moderate changes in results when some numerical SLAMM input parameters were varied highlighting the value of collecting long-term sedimentation, accretion and erosion data to improve SLAMM precision. The changes predicted by SLAMM will affect exposure of adjacent human communities to coastal hazards and ecosystem functions potentially resulting in impacts to property values, infrastructure investment and insurance rates. The results and process presented here can be used as a guide for communities vulnerable to SLR to identify and prioritize adaptation strategies that slow and/or accommodate the changes underway.

  19. A modeling study of coastal inundation induced by storm surge, sea-level rise, and subsidence in the Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Zhaoqing; Wang, Taiping; Leung, Lai-Yung R.; Hibbard, Kathleen A.; Janetos, Anthony C.; Kraucunas, Ian P.; Rice, Jennie S.; Preston, Benjamin; Wilbanks, Thomas

    2013-12-10

    The northern coasts of the Gulf of Mexico are highly vulnerable to the direct threats of climate change, such as hurricane-induced storm surge, and such risks can be potentially exacerbated by land subsidence and global sea level rise. This paper presents an application of a coastal storm surge model to study the coastal inundation process induced by tide and storm surge, and its response to the effects of land subsidence and sea level rise in the northern Gulf coast. An unstructured-grid Finite Volume Coastal Ocean Model was used to simulate tides and hurricane-induced storm surges in the Gulf of Mexico. Simulated distributions of co-amplitude and co-phase of semi-diurnal and diurnal tides are in good agreement with previous modeling studies. The storm surges induced by four historical hurricanes (Rita, Katrina, Ivan and Dolly) were simulated and compared to observed water levels at National Oceanic and Atmospheric Administration tide stations. Effects of coastal subsidence and future global sea level rise on coastal inundation in the Louisiana coast were evaluated using a parameter “change of inundation depth” through sensitivity simulations that were based on a projected future subsidence scenario and 1-m global sea level rise by the end of the century. Model results suggested that hurricane-induced storm surge height and coastal inundation could be exacerbated by future global sea level rise and subsidence, and that responses of storm surge and coastal inundation to the effects of sea level rise and subsidence are highly nonlinear and vary on temporal and spatial scales.

  20. U.S. Coastal Relief Model - Florida and East Gulf of Mexico

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NGDC's U.S. Coastal Relief Model (CRM) provides the first comprehensive view of the U.S. coastal zone integrating offshore bathymetry with land topography into a...

  1. Ship Response Capability Models for Counter-Piracy Patrols in the Gulf of Aden

    Science.gov (United States)

    2011-09-01

    9 2.1.2 Ripple Propagation Algorithm . . . . . . . . . . . . . . . . . . . 9 2.1.3 Marsaglia et al. Algorithm...of Marsaglia et al. (1990) . . . . . . . . . . . . . . . . . . . . . 47 Annex D: Error Calculations for 1D model...effectively patrolled by a particular asset. One 2D approach uses the an- alytical work of Marsaglia et al. [10] to generate the probability distribution of

  2. Epigenetic Mediation of Endocrine and Immune Response in an Animal Model of Gulf War Illness

    Science.gov (United States)

    2016-10-01

    immune system, genomics, mouse model 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a. NAME OF RESPONSIBLE...None Name: Nova Southeastern University Location: Institute for Neuro -Immune Medicine University Park Plaza 3440 South University Drive 19

  3. Comparison of individual-based model output to data using a model of walleye pollock early life history in the Gulf of Alaska

    Science.gov (United States)

    Hinckley, Sarah; Parada, Carolina; Horne, John K.; Mazur, Michael; Woillez, Mathieu

    2016-10-01

    Biophysical individual-based models (IBMs) have been used to study aspects of early life history of marine fishes such as recruitment, connectivity of spawning and nursery areas, and marine reserve design. However, there is no consistent approach to validating the spatial outputs of these models. In this study, we hope to rectify this gap. We document additions to an existing individual-based biophysical model for Alaska walleye pollock (Gadus chalcogrammus), some simulations made with this model and methods that were used to describe and compare spatial output of the model versus field data derived from ichthyoplankton surveys in the Gulf of Alaska. We used visual methods (e.g. distributional centroids with directional ellipses), several indices (such as a Normalized Difference Index (NDI), and an Overlap Coefficient (OC), and several statistical methods: the Syrjala method, the Getis-Ord Gi* statistic, and a geostatistical method for comparing spatial indices. We assess the utility of these different methods in analyzing spatial output and comparing model output to data, and give recommendations for their appropriate use. Visual methods are useful for initial comparisons of model and data distributions. Metrics such as the NDI and OC give useful measures of co-location and overlap, but care must be taken in discretizing the fields into bins. The Getis-Ord Gi* statistic is useful to determine the patchiness of the fields. The Syrjala method is an easily implemented statistical measure of the difference between the fields, but does not give information on the details of the distributions. Finally, the geostatistical comparison of spatial indices gives good information of details of the distributions and whether they differ significantly between the model and the data. We conclude that each technique gives quite different information about the model-data distribution comparison, and that some are easy to apply and some more complex. We also give recommendations for

  4. Model-based passive acoustic tracking of sperm whale foraging behavior in the Gulf of Alaska

    Science.gov (United States)

    Tiemann, Christopher; Thode, Aaron; Straley, Jan; Folkert, Kendall; O'Connell, Victoria

    2005-09-01

    In 2004, the Southeast Alaska Sperm Whale Avoidance Project (SEASWAP) introduced the use of passive acoustics to help monitor the behavior of sperm whales depredating longline fishing operations. Acoustic data from autonomous recorders mounted on longlines provide the opportunity to demonstrate a tracking algorithm based on acoustic propagation modeling while providing insight into whales' foraging behavior. With knowledge of azimuthally dependent bathymetry, a 3D track of whale motion can be obtained using data from just one hydrophone by exploiting multipath arrival information from recorded sperm whale clicks. The evolution of multipath arrival patterns is matched to range-, depth-, and azimuth-dependent modeled arrival patterns to generate an estimate of whale motion. This technique does not require acoustic ray identification (i.e., direct path, surface reflected, etc.) while still utilizing individual ray arrival information, and it can also account for all waveguide propagation physics such as interaction with range-dependent bathymetry and ray refraction.

  5. Studying methane migration mechanisms at Walker Ridge, Gulf of Mexico, via 3D methane hydrate reservoir modeling

    Energy Technology Data Exchange (ETDEWEB)

    Nole, Michael [University of Texas at Austin; Daigle, Hugh [University of Texas at Austin; Mohanty, Kishore [University of Texas at Austin; Cook, Ann [Ohio State University; Hillman, Jess [Ohio State University

    2015-12-15

    We have developed a 3D methane hydrate reservoir simulator to model marine methane hydrate systems. Our simulator couples highly nonlinear heat and mass transport equations and includes heterogeneous sedimentation, in-situ microbial methanogenesis, the influence of pore size contrast on solubility gradients, and the impact of salt exclusion from the hydrate phase on dissolved methane equilibrium in pore water. Using environmental parameters from Walker Ridge in the Gulf of Mexico, we first simulate hydrate formation in and around a thin, dipping, planar sand stratum surrounded by clay lithology as it is buried to 295mbsf. We find that with sufficient methane being supplied by organic methanogenesis in the clays, a 200x pore size contrast between clays and sands allows for a strong enough concentration gradient to significantly drop the concentration of methane hydrate in clays immediately surrounding a thin sand layer, a phenomenon that is observed in well log data. Building upon previous work, our simulations account for the increase in sand-clay solubility contrast with depth from about 1.6% near the top of the sediment column to 8.6% at depth, which leads to a progressive strengthening of the diffusive flux of methane with time. By including an exponentially decaying organic methanogenesis input to the clay lithology with depth, we see a decrease in the aqueous methane supplied to the clays surrounding the sand layer with time, which works to further enhance the contrast in hydrate saturation between the sand and surrounding clays. Significant diffusive methane transport is observed in a clay interval of about 11m above the sand layer and about 4m below it, which matches well log observations. The clay-sand pore size contrast alone is not enough to completely eliminate hydrate (as observed in logs), because the diffusive flux of aqueous methane due to a contrast in pore size occurs slower than the rate at which methane is supplied via organic methanogenesis

  6. A Modeling Study of Circulation and Eddies in the Persian Gulf

    Science.gov (United States)

    2010-04-01

    folding time scale of 1–76 days. GDEM3 is a global gridded ocean temperature and salinity clima - tology with a horizontal resolution of 1/38 and has 40...and time of occurrence. The temporal evolution of ICE illustrated in weekly maps of MODIS 4-km SST from 29 August to 22 September 2005 (Fig. 7) suggests...investigate whether the eddies were present on or before 29 August 2005 and to show their temporal evolution, we employ sequences of model cur- rents

  7. Understanding climate impacts on recruitment and spatial dynamics of Atlantic cod in the Gulf of Maine: Integration of observations and modeling

    Science.gov (United States)

    Runge, Jeffrey A.; Kovach, Adrienne I.; Churchill, James H.; Kerr, Lisa A.; Morrison, John R.; Beardsley, Robert C.; Berlinsky, David L.; Chen, Changsheng; Cadrin, Steven X.; Davis, Cabell S.; Ford, Kathryn H.; Grabowski, Jonathan H.; Howell, W. Huntting; Ji, Rubao; Jones, Rebecca J.; Pershing, Andrew J.; Record, Nicholas R.; Thomas, Andrew C.; Sherwood, Graham D.; Tallack, Shelly M. L.; Townsend, David W.

    2010-10-01

    We put forward a combined observing and modeling strategy for evaluating effects of environmental forcing on the dynamics of spatially structured cod populations spawning in the western Gulf of Maine. Recent work indicates at least two genetically differentiated complexes in this region: a late spring spawning, coastal population centered in Ipswich Bay, and a population that spawns in winter inshore and on nearshore banks in the Gulf of Maine and off southern New England. The two populations likely differ in trophic interactions and in physiological and behavioral responses to different winter and spring environments. Coupled physical-biological modeling has advanced to the point where within-decade forecasting of environmental conditions for recruitment to each of the two populations is feasible. However, the modeling needs to be supported by hydrographic, primary production and zooplankton data collected by buoys, and by data from remote sensing and fixed station sampling. Forecasts of environmentally driven dispersal and growth of planktonic early life stages, combined with an understanding of possible population-specific predator fields, usage of coastal habitat by juveniles and adult resident and migratory patterns, can be used to develop scenarios for spatially explicit population responses to multiple forcings, including climate change, anthropogenic impacts on nearshore juvenile habitat, connectivity among populations and management interventions such as regional fisheries closures.

  8. Colored Dissolved Organic Matter Dynamics in the Northern Gulf of Mexico from Ocean Color and Numerical Model Results

    Science.gov (United States)

    2014-07-01

    prevalent for the rest of the month. Point 2 exhibited longer periods of downcoast current patterns with intermittent southward changes in current...M.N.; Jose, F., and Patin, C., 2012. Seasonal hydrody- namics along the Louisiana Coast: implications for hypoxia spreading. Journal of Coastal Research...and Rabalais, N.N., 2006. Relationships among satellite chlorophyll a, river inputs, and hypoxia on the Louisiana continental shelf, Gulf of Mexico

  9. Fault slip-rates derived from modeling of on-shore marine terraces in the western Corinth Gulf

    Science.gov (United States)

    Palyvos, Nikos; De Martini, Paolo Marco; Mancini, Marco; Pantosti, Daniela

    2013-04-01

    Data available for estimating fault slip-rates from accurate modeling of uplifted on-shore marine terraces although limited are all derivatives of the research activity performed from 2004 to 2007 within the 3HAZ-Corinth project. We concentrated our efforts in the Aravonitsa area where we had a nicely preserved staircase of marine terraces. In particular, we recognized and mapped in detail all the marine terraces by qualitative DEM analysis, airphoto interpretation and field survey and we adopted a forward modeling procedure to fit the data. The modeling approach we used in this work does not take into account any effect related to sedimentation, compaction and erosion nor any interseismic adjustment and thus, being purely based on coseismic deformation, the obtained results should be considered as maxima. In the study area we were able to recognize several surfaces related to sea-level still stands. Their areal distribution and elevation are strongly influenced by past intense erosion on the underlying weakly consolidated sediments, and by the activity of secondary faults at the footwall of the Neos Erineos Fault, being part of the Lambiri - Neos Erineos - Aigion Fault zone (LANEfz). The Neos Erineos Fault has been studied and investigated in details and it appears as one of the main N-dipping normal faults bounding the southern shore of the Corinth Gulf and taking on part of the observed N-S striking extension. U/Th-series age dates and nannoplankton analyses, performed on selected samples collected at different heights on the studied surfaces, allowed us to to reconstruct an almost complete and chronologically well constrained transect of uplifted marine terraces belonging to the Late Quaternary (as old as 350 ka). A tentative correlation with marine isotopic stages (MIS) and specifically with main highstands from the Late Quaternary eustatic sea-level curve was attempted in order to calculate footwall uplift rate for the Neos Erineos Fault. The calculated

  10. Source Characterization and Tsunami Modeling of Submarine Landslides Along the Yucatán Shelf/Campeche Escarpment, Southern Gulf of Mexico

    Science.gov (United States)

    Chaytor, Jason D.; Geist, Eric L.; Paull, Charles K.; Caress, David W.; Gwiazda, Roberto; Fucugauchi, Jaime Urrutia; Vieyra, Mario Rebolledo

    2016-12-01

    Submarine landslides occurring along the margins of the Gulf of Mexico (GOM) represent a low-likelihood, but potentially damaging source of tsunamis. New multibeam bathymetry coverage reveals that mass wasting is pervasive along the Yucatán Shelf edge with several large composite landslides possibly removing as much as 70 km3 of the Cenozoic sedimentary section in a single event. Using GIS-based analysis, the dimensions of six landslides from the central and northern sections of the Yucatán Shelf/Campeche Escarpment were determined and used as input for preliminary tsunami generation and propagation models. Tsunami modeling is performed to compare the propagation characteristics and distribution of maximum amplitudes throughout the GOM among the different landslide scenarios. Various factors such as landslide geometry, location along the Yucatán Shelf/Campeche Escarpment, and refraction during propagation result in significant variations in the affected part of the Mexican and US Gulf Coasts. In all cases, however, tsunami amplitudes are greatest along the northern Yucatán Peninsula.

  11. A coupled physical-biological model of the Northern Gulf of Mexico shelf: model description, validation and analysis of phytoplankton variability

    Directory of Open Access Journals (Sweden)

    K. Fennel

    2011-07-01

    Full Text Available The Texas-Louisiana shelf in the Northern Gulf of Mexico receives large inputs of nutrients and freshwater from the Mississippi/Atchafalaya River system. The nutrients stimulate high rates of primary production in the river plume, which contributes to the development of a large and recurring hypoxic area in summer, but the mechanistic links between hypoxia and river discharge of freshwater and nutrients are complex as the accumulation and vertical export of organic matter, the establishment and maintenance of vertical stratification, and the microbial degradation of organic matter are controlled by a non-linear interplay of factors. Unraveling these interactions will have to rely on a combination of observations and models. Here we present results from a realistic, 3-dimensional, physical-biological model with focus on a quantification of nutrient-stimulated phytoplankton growth, its variability and the fate of this organic matter. We demonstrate that the model realistically reproduces many features of observed nitrate and phytoplankton dynamics including observed property distributions and rates. We then contrast the environmental factors and phytoplankton source and sink terms characteristic of three model subregions that represent an ecological gradient from eutrophic to oligotrophic conditions. We analyze specifically the reasons behind the counterintuitive observation that primary production in the light-limited plume region near the Mississippi River delta is positively correlated with river nutrient input, and find that, while primary production and phytoplankton biomass are positively correlated with nutrient load, phytoplankton growth rate is not. This suggests that accumulation of biomass in this region is not primarily controlled bottom up by nutrient-stimulation, but top down by systematic differences in the loss processes.

  12. Assessing the recurrence of big earthquakes and tsunami in the Gulf of Cadiz (SW Iberia) using thin-sheet neotectonic modeling

    Science.gov (United States)

    Cunha, T.; Matias, L. M.; Terrinha, P.; Negredo, A.; Rosas, F.; Fernandes, R.; Pinheiro, L.

    2008-12-01

    The eastern end of the Azores-Gibraltar plate boundary is characterized by distributed deformation that accommodates the collision between the Eurasia and Africa plates. Despite this, the active faults in the area can generate very large earthquakes and destructive tsunamis, such as the Great Lisbon Earthquake, that occurred in the 1st November 1755 (estimated Mw = 8.7). The largest instrumental earthquake recorded was the 28th of February 1969 Mw=8.0, localized in the Horseshoe abyssal plain with a thrust fault mechanism. In this study we used a thin-shell approximation (SHELLS- Bird, P., Computers and Geosciences, 25, 383- 394, 1999) to model the neotectonics of this segment of the Africa-Eurasia plate boundary and put constraints on the recurrence periods of earthquakes and tsunamis. In relation to previous neotectonic models in the region we use a better constrained structural map, particularly in the Gulf of Cadiz and SW Iberia, based on recently acquired multi-beam bathymetry, backscatter data and numerous high quality multi- channel seismic profiles. Importantly, the map shows the existence of several NNE-SSW to ENE-WSW thrust faults, associated to prominent bathymetric features, and a set of very long (up to 600 km) strike-slip lineaments, extending between the western Horseshoe Abyssal Plain and the eastern Gulf of Cadiz. Different models have been tested, for various boundary scenarios (geometry and plate velocities) and fault networks, and the results compared with seismic strain release, recent GPS observations and stress orientation. The modeling suggests that, when mature, the long strike-slip lineaments will accommodate most of the relative motion between Eurasia and Africa (aprox. 4 mm/a) along a "transform-type" plate boundary. This situation, however, is associated with only minor thrust faulting in the region and predicts a strong attenuation of the velocity field between the northern Morocco and Gibraltar, in contradiction with present day GPS

  13. A coupled physical-biological model of the Northern Gulf of Mexico shelf: model description, validation and analysis of phytoplankton variability

    Directory of Open Access Journals (Sweden)

    K. Fennel

    2011-01-01

    Full Text Available The Texas-Louisiana shelf in the Northern Gulf of Mexico receives large inputs of nutrients and freshwater from the Mississippi/Atchafalaya River system. The nutrients stimulate high rates of primary production in the river plume, which contributes to the development of a large and recurring hypoxic area in summer. The mechanistic links between hypoxia and river discharge of freshwater and nutrients are complex as the accumulation and vertical export of organic matter, the establishment and maintenance of vertical stratification, and the microbial degradation of organic matter are controlled by a non-linear interplay of factors. We present results from a realistic, 3-dimensional, physical-biological model that includes the processes thought to be of first order importance to hypoxia formation and demonstrate that the model realistically reproduces many features of observed nitrate and phytoplankton dynamics including observed property distributions and rates. We then contrast the environmental factors and phytoplankton source and sink terms characteristic of three model subregions that represent an ecological gradient from eutrophic to oligotrophic conditions. We analyze specifically the reasons behind the counterintuitive observation that primary production in the light-limited plume region near the Mississippi River delta is positively correlated with river nutrient input. We find that, while primary production and phytoplankton biomass are positively correlated with nutrient load, phytoplankton growth rate is not. This suggests that accumulation of biomass in this region is not primarily controlled bottom up by nutrient-stimulation, but top down by systematic differences in the loss processes. We hypothesize that increased retention of river water in high discharge years explains this phenomenon.

  14. A modeling study of the role that bottom topography plays in Gulf Stream dynamics and in influencing the tilt of mean sea level along the US East Coast

    Science.gov (United States)

    Ezer, Tal

    2017-05-01

    Two aspects of the interactions between the Gulf Stream (GS) and the bottom topography are investigated: 1. the spatial variations associated with the north-south tilt of mean sea level along the US East Coast and 2. the high-frequency temporal variations of coastal sea level (CSL) that are related to Gulf Stream dynamics. A regional ocean circulation model is used to assess the role of topography; this is done by conducting numerical simulations of the GS with two different topographies-one case with a realistic topography and another case with an idealized smooth topography that neglects the details of the coastline and the very deep ocean. High-frequency oscillations (with a 5-day period) in the zonal wind and in the GS transport are imposed on the model; the source of the GS variability is either the Florida Current (FC) in the south or the Slope Current (SC) in the north. The results demonstrate that the abrupt change of topography at Cape Hatteras, near the point where the GS separates from the coast, amplifies the northward downward mean sea level tilt along the coast there. The results suggest that idealized or coarse resolution models that do not resolve the details of the coastline may underestimate the difference between the higher mean sea level in the South Atlantic Bight (SAB) and the lower mean sea level in the Mid-Atlantic Bight (MAB). Imposed variations in the model's GS transport can generate coherent sea level variability along the coast, similar to the observations. However, when the bottom topography in the model is modified (or not well resolved), the shape of the coastline and the continental shelf influence the propagation of coastal-trapped waves and impact the CSL variability. The results can explain the different characteristics of sea level variability in the SAB and in the MAB and help understand unexpected water level anomalies and flooding related to remote influence of the GS.

  15. Rings dominate western Gulf

    Science.gov (United States)

    Vidal L., Francisco V.; Vidal L., Victor M. V.; Molero, José María Pérez

    Surface and deep circulation of the central and western Gulf of Mexico is controlled by interactions of rings of water pinched from the gulf's Loop Current. The discovery was made by Mexican oceanographers who are preparing a full-color, 8-volume oceanographic atlas of the gulf.Anticyclonic warm-core rings pinch off the Loop Current at a rate of about one to two per year, the scientists of the Grupo de Estudios Oceanográficos of the Instituto de Investigaciones Eléctricas (GEO-IIE) found. The rings migrate west until they collide with the continental shelf break of the western gulf, almost always between 22° and 23°N latitude. On their westward travel they transfer angular momentum and vorticity to the surrounding water, generating cyclonic circulations and vortex pairs that completely dominate the entire surface and deep circulation of the central and western gulf.

  16. Modeling connectivity of walleye pollock in the Gulf of Alaska: Are there any linkages to the Bering Sea and Aleutian Islands?

    Science.gov (United States)

    Parada, Carolina; Hinckley, Sarah; Horne, John; Mazur, Michael; Hermann, Albert; Curchister, Enrique

    2016-10-01

    We investigated the connectivity of walleye pollock in the Gulf of Alaska (GOA) and linkages to the Bering Sea (BS) and Aleutian Island (AL) regions. We used a spatially-explicit Individual-based model (IBM) coupled to 6 years of a hydrodynamic model that simulates the early life history of walleye pollock in the GOA (eggs to age-0 juveniles). The processes modeled included growth, movement, mortality, feeding and the bioenergetics component for larvae and juveniles. Simulations were set to release particles on the 1st of the month (February to May) in fourteen historical spawning areas in the GOA up to the 1st of September each year. Model results reproduced the link between the Shelikof Strait spawning area and the Shumagin nursery region for March and April spawners, besides other Potential Nursery Areas (PNAs) found in the GOA. A prominent finding of this study was the appearance of the BS as important PNAs for several GOA spawning grounds, which is supported by a consistent flow into the BS through Unimak Pass. The simulations showed the highest density of simulated surviving pollock in the western Bering Sea (WBS) region with the lowest coefficients of variation of the whole domain. Three spawning sectors were defined, which aggregate multiple spawning areas in the eastern (EGOA), central (CGOA) and western Gulf of Alaska (WGOA). A connectivity matrix showed strong retention within the CGOA (25.9%) and EGOA (23.8%), but not in the WGOA (7.2%). Within the GOA, the highest connectivity is observed from EGOA to CGOA (57.8%) followed by the connection from CGOA to WGOA (24.3%). Overall, one of the most prominent connections was from WGOA to WBS (62.8%), followed by a connection from CGOA to WBS (29.2%). In addition, scenarios of shifting spawning locations and nursery sectors of GOA, BS and AL are explored and implications for walleye pollock stock structure hypotheses are discussed.

  17. The influence of the Gulf Stream on wintertime European blocking

    Science.gov (United States)

    O'Reilly, Christopher H.; Minobe, Shoshiro; Kuwano-Yoshida, Akira

    2016-09-01

    Wintertime blocking is responsible for extended periods of anomalously cold and dry weather over Europe. In this study, the influence of the Gulf Stream sea surface temperature (SST) front on wintertime European blocking is investigated using a reanalysis dataset and a pair of atmospheric general circulation model (AGCM) simulations. The AGCM is forced with realistic and smoothed Gulf Stream SST, and blocking frequency over Europe is found to depend crucially on the Gulf Stream SST front. In the absence of the sharp SST gradient European blocking is significantly reduced and occurs further downstream. The Gulf Stream is found to significantly influence the surface temperature anomalies during blocking periods and the occurrence of associated cold spells. In particular the cold spell peak, located in central Europe, disappears in the absence of the Gulf Stream SST front. The nature of the Gulf Stream influence on European blocking development is then investigated using composite analysis. The presence of the Gulf Stream SST front is important in capturing the observed quasi-stationary development of European blocking. The development is characterised by increased lower-tropospheric meridional eddy heat transport in the Gulf Stream region and increased eddy kinetic energy at upper-levels, which acts to reinforce the quasi-stationary jet. When the Gulf Stream SST is smoothed the storm track activity is weaker, the development is less consistent and European blocking occurs less frequently.

  18. Effects of lateral processes on the seasonal water stratification of the Gulf of Finland: 3-D NEMO-based model study

    Science.gov (United States)

    Vankevich, Roman E.; Sofina, Ekaterina V.; Eremina, Tatiana E.; Ryabchenko, Vladimir A.; Molchanov, Mikhail S.; Isaev, Alexey V.

    2016-08-01

    This paper aims to fill the gaps in knowledge of processes affecting the seasonal water stratification in the Gulf of Finland (GOF). We used a state-of-the-art modelling framework NEMO (Nucleus for European Modelling of the Ocean) designed for oceanographic research, operational oceanography, seasonal forecasting, and climate studies to build an eddy-resolving model of the GOF. To evaluate the model skill and performance, two different solutions were obtained on 0.5 km eddy-resolving and commonly used 2 km grids for a 1-year simulation. We also explore the efficacy of non-hydrostatic effect (convection) parameterizations available in NEMO for coastal application. It is found that the solutions resolving submesoscales have a more complex mixed layer structure in the regions of the GOF directly affected by the upwelling/downwelling and intrusions from the open Baltic Sea. Presented model estimations of the upper mixed layer depth are in good agreement with in situ CTD (BED) data. A number of model sensitivity tests to the vertical mixing parameterization confirm the model's robustness. Further progress in the submesoscale process simulation and understanding is apparently not connected mainly with the finer resolution of the grids, but with the use of non-hydrostatic models because of the failure of the hydrostatic approach at submesoscale.

  19. Ecological Modeling Guide for Ecosystem Restoration and Management

    Science.gov (United States)

    2012-08-01

    bioenergetics model into a spatially explicit water quality model : Application to menhaden in Chesapeake Bay. Ecological Modelling 221: 1922-1933...ER D C/ EL T R -1 2 -1 8 Environmental Benefits Analysis Program Ecological Modeling Guide for Ecosystem Restoration and Management E nv...distribution is unlimited. Environmental Benefits Analysis Program ERDC/EL TR-12-18 August 2012 Ecological Modeling Guide for Ecosystem Restoration and

  20. Comparison of MELCOR modeling techniques and effects of vessel water injection on a low-pressure, short-term, station blackout at the Grand Gulf Nuclear Station

    Energy Technology Data Exchange (ETDEWEB)

    Carbajo, J.J.

    1995-06-01

    A fully qualified, best-estimate MELCOR deck has been prepared for the Grand Gulf Nuclear Station and has been run using MELCOR 1.8.3 (1.8 PN) for a low-pressure, short-term, station blackout severe accident. The same severe accident sequence has been run with the same MELCOR version for the same plant using the deck prepared during the NUREG-1150 study. A third run was also completed with the best-estimate deck but without the Lower Plenum Debris Bed (BH) Package to model the lower plenum. The results from the three runs have been compared, and substantial differences have been found. The timing of important events is shorter, and the calculated source terms are in most cases larger for the NUREG-1150 deck results. However, some of the source terms calculated by the NUREG-1150 deck are not conservative when compared to the best-estimate deck results. These results identified some deficiencies in the NUREG-1150 model of the Grand Gulf Nuclear Station. Injection recovery sequences have also been simulated by injecting water into the vessel after core relocation started. This marks the first use of the new BH Package of MELCOR to investigate the effects of water addition to a lower plenum debris bed. The calculated results indicate that vessel failure can be prevented by injecting water at a sufficiently early stage. No pressure spikes in the vessel were predicted during the water injection. The MELCOR code has proven to be a useful tool for severe accident management strategies.

  1. Selective Toxicity of Persian Gulf Sea Cucumber (Holothuria parva and Sponge (Haliclona oculata Methanolic Extracts on Liver Mitochondria Isolated from an Animal Model of Hepatocellular Carcinoma

    Directory of Open Access Journals (Sweden)

    Seydi

    2015-12-01

    Full Text Available Background Natural products isolated from marine environments are well known for their pharmacodynamic potential in diverse disease treatments, such as for cancer or inflammatory conditions. Sea cucumbers are marine animals of the phylum Echinoderm and the class Holothuroidea, with leathery skin and gelatinous bodies. Sponges are important components of Persian Gulf animal communities, and the marine sponges of the genus Haliclona have been known to display broad-spectrum biological activity. Many studies have shown that sea cucumbers and sponges contain antioxidants and anti-cancer compounds. Objectives This study was designed to determine the selective toxicity of Persian Gulf sea cucumber (Holothuria parva and sponge (Haliclona oculata methanolic extracts on liver mitochondria isolated from an animal model of hepatocellular carcinoma, as part of a national project that hopes to identify novel potential anticancer candidates among Iranian Persian Gulf flora and fauna. Materials and Methods To induce hepatocarcinogenesis, rats were given diethylnitrosamine (DEN injections (200 mg/kg i.p. by a single dose, and then the cancer was promoted with 2-acetylaminofluorene (2-AAF (0.02 w/w for two weeks. Histopathological evaluations were performed, and levels of liver injury markers and a specific liver cancer marker (alpha-fetoprotein, were determined for confirmation of hepatocellular carcinoma induction. Finally, mitochondria were isolated from cancerous and non-cancerous hepatocytes. Results Our results showed that H. parva methanolic extracts (250, 500, and 1000 µg/mL and H. oculata methanolic extracts (200, 400, and 800 µg/mL increased reactive oxygen species (ROS formation, mitochondrial membrane potential (MMP, mitochondrial swelling, and cytochrome c release in the mitochondria obtained from cancerous hepatocytes, but not in mitochondria obtained from non-cancerous liver hepatocytes. These extracts also induced caspase-3 activation, which is

  2. Effects of lateral processes on the seasonal water stratification of the Gulf of Finland: 3-D NEMO-based model study

    Directory of Open Access Journals (Sweden)

    R. E. Vankevich

    2015-10-01

    Full Text Available This paper tries to fill the gaps in knowledge of processes affecting the seasonal water stratification in the Gulf of Finland (GOF. We used state-of-the-art modeling framework NEMO aimed for oceanographic research, operational oceanography, seasonal forecasting and climate studies to build an eddy resolving model of the GOF. To evaluate the model skill and performance two different solutions where obtained on 0.5 km eddy resolving and commonly used 2 km grids for one year simulation. We also explore the efficacy of nonhydrostatic effect (convection parameterizations available in NEMO for coastal application. It is found that the solutions resolving sub-mesoscales have a more complex mixed layer structure in the regions of GOF directly affected by the upwelling/downwelling and intrusions from the open Baltic Sea. Presented model estimations of the upper mixed layer depth are in a good agreement with in situ CTD data. A number of model sensitivity tests to the vertical mixing parameterization confirm the model robustness.

  3. Gulf Shrimp System

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gulf of Mexico Shrimp Landings - This data set contains catch (landed catch) and effort for fishing trips made by the larger vessels that fish near and offshore for...

  4. Gulf Sturgeon Facts

    Science.gov (United States)

    Sulak, Kenneth J.; Randall, Michael

    2008-01-01

    Sturgeon: An ancient type of fish, with 5 rows of armor scutes, a cartilaginous skeleton, long snout, suction mouth, no teeth, and 4 barbels. Photograph of a Gulf sturgeon. The total length of a 5-month old is 313 mm.

  5. Production of Omega-3 Fatty Acid Ethyl Esters from Menhaden Oil Using Proteus vulgaris Lipase-Mediated One-Step Transesterification and Urea Complexation.

    Science.gov (United States)

    Kim, Soo-Jin; Kim, Hyung Kwoun

    2016-05-01

    An organic solvent-stable lipase from Proteus vulgaris K80 was used to produce the omega-3 polyunsaturated fatty acid ethyl esters (ω-3 PUFA EEs). First, the lyophilized recombinant lipase K80 (LyoK80) was used to perform the transesterification reaction of menhaden oil and ethanol. LyoK80 produced the ω-3 PUFA EEs with a conversion yield of 82 % in the presence of 20 % water content via a three-step ethanol-feeding process; however, in a non-aqueous condition, LyoK80 produced only a slight amount of the ω-3 PUFA EEs. To enhance its reaction properties, the lipase K80 was immobilized on a hydrophobic bead to derive ImmK80; the biochemical properties and substrate specificity of ImmK80 are similar to those of LyoK80. ImmK80 was then used to produce ω-3 PUFA EEs in accordance with the same transesterification reaction. Unlike LyoK80, ImmK80 achieved a high ω-3 PUFA EE conversion yield of 86 % under a non-aqueous system via a one-step ethanol-feeding reaction. The ω-3 PUFA EEs were purified up to 92 % using a urea complexation method.

  6. Gulf Petro Initiative

    Energy Technology Data Exchange (ETDEWEB)

    Fathi Boukadi

    2011-02-05

    In this report, technologies for petroleum production and exploration enhancement in deepwater and mature fields are developed through basic and applied research by: (1) Designing new fluids to efficiently drill deepwater wells that can not be cost-effectively drilled with current technologies. The new fluids will be heavy liquid foams that have low-density at shallow dept to avoid formation breakdown and high density at drilling depth to control formation pressure. The goal of this project is to provide industry with formulations of new fluids for reducing casing programs and thus well construction cost in deepwater development. (2) Studying the effects of flue gas/CO{sub 2} huff n puff on incremental oil recovery in Louisiana oilfields bearing light oil. An artificial neural network (ANN) model will be developed and used to map recovery efficiencies for candidate reservoirs in Louisiana. (3) Arriving at a quantitative understanding for the three-dimensional controlled-source electromagnetic (CSEM) geophysical response of typical Gulf of Mexico hydrocarbon reservoirs. We will seek to make available tools for the qualitative, rapid interpretation of marine CSEM signatures, and tools for efficient, three-dimensional subsurface conductivity modeling.

  7. Comparison of modeling methods to predict the spatial distribution of deep-sea coral and sponge in the Gulf of Alaska

    Science.gov (United States)

    Rooper, Christopher N.; Zimmermann, Mark; Prescott, Megan M.

    2017-08-01

    Deep-sea coral and sponge ecosystems are widespread throughout most of Alaska's marine waters, and are associated with many different species of fishes and invertebrates. These ecosystems are vulnerable to the effects of commercial fishing activities and climate change. We compared four commonly used species distribution models (general linear models, generalized additive models, boosted regression trees and random forest models) and an ensemble model to predict the presence or absence and abundance of six groups of benthic invertebrate taxa in the Gulf of Alaska. All four model types performed adequately on training data for predicting presence and absence, with regression forest models having the best overall performance measured by the area under the receiver-operating-curve (AUC). The models also performed well on the test data for presence and absence with average AUCs ranging from 0.66 to 0.82. For the test data, ensemble models performed the best. For abundance data, there was an obvious demarcation in performance between the two regression-based methods (general linear models and generalized additive models), and the tree-based models. The boosted regression tree and random forest models out-performed the other models by a wide margin on both the training and testing data. However, there was a significant drop-off in performance for all models of invertebrate abundance ( 50%) when moving from the training data to the testing data. Ensemble model performance was between the tree-based and regression-based methods. The maps of predictions from the models for both presence and abundance agreed very well across model types, with an increase in variability in predictions for the abundance data. We conclude that where data conforms well to the modeled distribution (such as the presence-absence data and binomial distribution in this study), the four types of models will provide similar results, although the regression-type models may be more consistent with

  8. Can the Gulf Stream induce coherent short-term fluctuations in sea level along the US East Coast? A modeling study

    Science.gov (United States)

    Ezer, Tal

    2016-02-01

    Much attention has been given in recent years to observations and models that show that variations in the transport of the Atlantic Meridional Overturning Circulation (AMOC) and in the Gulf Stream (GS) can contribute to interannual, decadal, and multi-decadal variations in coastal sea level (CSL) along the US East Coast. However, less is known about the impact of short-term (time scales of days to weeks) fluctuations in the GS and their impact on CSL anomalies. Some observations suggest that these anomalies can cause unpredictable minor tidal flooding in low-lying areas when the GS suddenly weakens. Can these short-term CSL variations be attributed to changes in the transport of the GS? An idealized numerical model of the GS has been set up to test this proposition. The regional model uses a 1/12° grid with a simplified coastline to eliminate impacts from estuaries and small-scale coastal features and thus isolate the GS impact. The GS in the model is driven by inflows/outflows, representing the Florida Current (FC), the Slope Current (SC), and the Sargasso Sea (SS) flows. Forcing the model with an oscillatory FC transport with a period of 2, 5, and 10 days produced coherent CSL variations from Florida to the Gulf of Maine with similar periods. However, when imposing variations in the transports of the SC or the SS, they induce CSL variations only north of Cape Hatteras. The suggested mechanism is that variations in GS transport produce variations in sea level gradient across the entire GS length and this large-scale signal is then transmitted into the shelf by the generation of coastal-trapped waves (CTW). In this idealized model, the CSL variations induced by variations of ˜10 Sv in the transport of the GS are found to resemble CSL variations induced by ˜5 m s-1 zonal wind fluctuations, though the mechanisms of wind-driven and GS-driven sea level are quite different. Better understanding of the relation between variations in offshore currents and CSL will help

  9. USING MCSST METHOD FOR MEASURING SEA SURFACE TEMPERATURE WITH MODIS IMAGERY AND MODELING AND PREDICTION OF REGIONAL VARIATIONS WITH LEAST SQUARES METHOD (CASE STUDY: PERSIAN GULF, IRAN

    Directory of Open Access Journals (Sweden)

    M. S. Pakdaman

    2013-10-01

    Full Text Available Nowadays, many researchers in the area of thermal remote sensing applications believe in the necessity of modeling in environmental studies. Modeling in the remotely sensed data and the ability to precisely predict variation of various phenomena, persuaded the experts to use this knowledge increasingly. Suitable model selection is the basis for modeling and is a defining parameter. So, firstly the model should be identified well. The least squares method is for data fitting. In the least squares method, the best fit model is the model that minimizes the sum of squared residuals. In this research, that has been done for modeling variations of the Persian Gulf surface temperature, after data preparation, data gathering has been done with multi-channel method using the MODIS Terra satellites imagery. All the temperature data has been recorded in the period of ten years in winter time from December 2003 to January 2013 with dimensions of 20*20 km and for an area of 400 km2. Subsequently, 12400 temperature samples and variation trend control based on their fluctuation time have been observed. Then 16 mathematical models have been created for model building. After model creation, the variance of all the models has been calculated with ground truth for model testing. But the lowest variance was in combined models from degree 1 to degree 4. The results have shown that outputs for combined models of degree 1 to degree 3 and degree 1 to degree 4 for variables does not show significant differences and implementation of degree 4 does not seem necessary. Employment of trigonometric functions on variables increased the variance in output data. Comparison of the most suitable model and the ground truth showed a variance of just 1⁰. The number of samples, after elimination of blunders reduced to 11600 samples. After this elimination, all the created models have been run on the variables. Also in this case, the highest variance has been obtained for the models

  10. Antidepressant-like effects of omega-3 fatty acids in postpartum model of depression in rats.

    Science.gov (United States)

    Arbabi, Leila; Baharuldin, Mohamad Taufik Hidayat; Moklas, Mohamad Aris Mohamad; Fakurazi, Sharida; Muhammad, Sani Ismaila

    2014-09-01

    Postpartum depression (PPD) is a psychiatric disorder that occurs in 10-15% of childbearing women. It is hypothesized that omega-3 fatty acids, which are components of fish oil, may attenuate depression symptoms. In order to examine this hypothesis, the animal model of postpartum depression was established in the present study. Ovariectomized female rats underwent hormone-simulated pregnancy (HSP) regimen and received progesterone and estradiol benzoate or vehicle for 23 days, mimicking the actual rat's pregnancy. The days after hormone termination were considered as the postpartum period. Forced feeding of menhaden fish oil, as a source of omega-3, with three doses of 1, 3, and 9g/kg/d, fluoxetine 15mg/kg/d, and distilled water 2ml/d per rat started in five postpartum-induced and one vehicle group on postpartum day 1 and continued for 15 consecutive days. On postpartum day 15, all groups were tested in the forced swimming test (FST) and open field test (OFT), followed by a biochemical assay. Results showed that the postpartum-induced rats not treated with menhaden fish oil, exhibited an increase in immobility time seen in FST, hippocampal concentration of corticosterone and plasmatic level of corticosterone, and pro-inflammatory cytokines. These depression-related effects were attenuated by supplementation of menhaden fish oil with doses of 3 and 9g/kg. Moreover, results of rats supplemented with menhaden fish oil were comparable to rats treated with the clinically effective antidepressant, fluoxetine. Taken together, these results suggest that menhaden fish oil, rich in omega-3, exerts beneficial effect on postpartum depression and decreases the biomarkers related to depression such as corticosterone and pro-inflammatory cytokines. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  11. Gulf Island National Wildlife Refuges

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document provides a brief history and describes physical features of the Gulf Island National Wildlife Refuges. The Gulf Island National Wildlife Refuges...

  12. Model-based remote sensing algorithms for particulate organic carbon (POC) in the Northeastern Gulf of Mexico

    Indian Academy of Sciences (India)

    Young Baek Son; Wilford D Gardner; Alexey V Mishonov; Mary Jo Richardson

    2009-02-01

    Hydrographic data, including particulate organic carbon (POC) from the Northeastern Gulf of Mexico (NEGOM) study, were combined with remotely-sensed SeaWiFS data to estimate POC concentration using principal component analysis (PCA). The spectral radiance was extracted at each NEGOM station, digitized, and averaged. The mean value and spurious trends were removed from each spectrum. De-trended data included six wavelengths at 58 stations. The correlation between the weighting factors of the first six eigenvectors and POC concentration were applied using multiple linear regression. PCA algorithms based on the first three, four, and five modes accounted for 90, 95, and 98% of total variance and yielded significant correlations with POC with 2 = 0.89, 0.92, and 0.93. These full waveband approaches provided robust estimates of POC in various water types. Three different analyses (root mean square error, mean ratio and standard deviation) showed similar error estimates, and suggest that spectral variations in the modes defined by just the first four characteristic vectors are closely correlated with POC concentration, resulting in only negligible loss of spectral information from additional modes. The use of POC algorithms greatly increases the spatial and temporal resolution for interpreting POC cycling and can be extrapolated throughout and perhaps beyond the area of shipboard sampling.

  13. Numerical Modeling of the Effects of Nutrient-rich Coastal-water Input on the Phytoplankton in the Gulf of California

    Science.gov (United States)

    Bermudez, A.; Rivas, D.

    2015-12-01

    Phytoplankton bloom dynamics depends on the interactions of favorable physical, chemical, and biotic conditions, particularly on the available nutrients that enhance phytoplankton growth, like nitrogen. Costal and estuarine environments are heavily influenced by exogenous sources of nitrogen; the anthropogenic inputs include urban and rural wastewater coming from agricultural activities (i.e., fertilizers and animal waste). In response, new production is often enhanced, leading eutrophication and phytoplankton blooms, including harmful taxa. These events have become more frequent, and with it the interest to evaluate their effects on marine ecosystems and the impact on human health. In the Gulf of California the harmful algal blooms (HABs) had affected aquaculture, fisheries, and even tourism, thereby it is important to generate information about biological and physical factors that can influence their appearance. A numerical model is a tool that may bring key information about the origin and distribution of phytoplankton blooms. Herein the analysis is based on a three-dimensional, hydrodynamical numerical model, coupled to a Nitrogen-Phytoplankton-Zooplankton-Detritus (NPZD) model. Several numerical simulations using different forcing and scenarios are carried out in order to evaluate the processes that influence the phytoplankton growth. These numerical results are compared to available observations. Thus, the main environmental factors triggering the generation of HABs can be identified.

  14. A probabilistic approach for a cost-benefit analysis of oil spill management under uncertainty: A Bayesian network model for the Gulf of Finland.

    Science.gov (United States)

    Helle, Inari; Ahtiainen, Heini; Luoma, Emilia; Hänninen, Maria; Kuikka, Sakari

    2015-08-01

    Large-scale oil accidents can inflict substantial costs to the society, as they typically result in expensive oil combating and waste treatment operations and have negative impacts on recreational and environmental values. Cost-benefit analysis (CBA) offers a way to assess the economic efficiency of management measures capable of mitigating the adverse effects. However, the irregular occurrence of spills combined with uncertainties related to the possible effects makes the analysis a challenging task. We develop a probabilistic modeling approach for a CBA of oil spill management and apply it in the Gulf of Finland, the Baltic Sea. The model has a causal structure, and it covers a large number of factors relevant to the realistic description of oil spills, as well as the costs of oil combating operations at open sea, shoreline clean-up, and waste treatment activities. Further, to describe the effects on environmental benefits, we use data from a contingent valuation survey. The results encourage seeking for cost-effective preventive measures, and emphasize the importance of the inclusion of the costs related to waste treatment and environmental values in the analysis. Although the model is developed for a specific area, the methodology is applicable also to other areas facing the risk of oil spills as well as to other fields that need to cope with the challenging combination of low probabilities, high losses and major uncertainties.

  15. Quantifying cross-shelf and vertical nutrient flux in the Coastal Gulf of Alaska with a spatially nested, coupled biophysical model

    Science.gov (United States)

    Hermann, Albert J.; Hinckley, Sarah; Dobbins, Elizabeth L.; Haidvogel, Dale B.; Bond, Nicholas A.; Mordy, Calvin; Kachel, Nancy; Stabeno, Phyllis J.

    2009-12-01

    The Coastal Gulf of Alaska (CGOA) is productive, with large populations of fish, seabirds, and marine mammals; yet it is subject to downwelling-favorable coastal winds. Downwelling regions in other parts of the world are typically much less productive than their upwelling counterparts. Alternate sources of nutrients to feed primary production in the topographically complex CGOA are poorly known and difficult to quantify. Here we diagnose the output from a spatially nested, coupled hydrodynamic and lower trophic level model of the CGOA, to quantify both horizontal and vertical nutrient fluxes into the euphotic zone. Our nested model includes both nitrogen and iron limitation of phytoplankton production, and is driven by a fine-scale atmospheric model that resolves the effects of local orography on the coastal winds. Results indicate significant "rivers" of cross-shelf nitrogen flux due to horizontal advection, as well as "fountains" of vertical transport over shallow banks due to tidal mixing. Using these results, we constructed a provisional budget of nutrient transport among subregions of the CGOA. Contrary to expectations, this budget reveals substantial upwelling of nutrients over major portions of the shelf, driven by local wind-stress curl. These effects are large enough to overwhelm the smaller downwelling flux at the coast throughout the growing season. Vertical mixing by winds and tides, and horizontal flux from the deep basin, are other substantial contributors to nutrients above the 15-m horizon. These findings help to explain the productivity of this coastal ecosystem.

  16. Using Coupled Models to Study the Effects of River Discharge on Biogeochemical Cycling and Hypoxia in the Northern Gulf of Mexico

    Science.gov (United States)

    Penta, Bradley; Ko, D.; Gould, Richard W.; Arnone, Robert A.; Greene, R.; Lehrter, J.; Hagy, James; Schaeffer, B.; Murrell, M.; Kurtz, J.; Herchenroder, B.; Green, R.; Eldridge, P.

    2009-01-01

    We describe emerging capabilities to understand physical processes and biogeoehemical cycles in coastal waters through the use of satellites, numerical models, and ship observations. Emerging capabilities provide significantly improved ability to model ecological systems and the impact of environmental management actions on them. The complex interaction of physical and biogeoehemical processes responsible for hypoxic events requires an integrated approach to research, monitoring, and modeling in order to fully define the processes leading to hypoxia. Our efforts characterizes the carbon cycle associated with river plumes and the export of organic matter and nutrients form coastal Louisiana wetlands and embayments in a spatially and temporally intensive manner previously not possible. Riverine nutrients clearly affect ecosystems in the northern Gulf of Mexico as evidenced in the occurrence of regional hypoxia events. Less known and largely unqualified is the export of organic matter and nutrients from the large areas of disappearing coastal wetlands and large embayments adjacent to the Louisiana Continental Shelf. This project provides new methods to track the river plume along the shelf and to estimate the rate of export of suspended inorganic and organic paniculate matter and dissolved organic matter form coastal habitats of south Louisiana.

  17. On the three-dimensional numerical modeling of the deep circulation around Ángel de la Guarda Island in the Gulf of California

    Science.gov (United States)

    Marinone, S. G.

    2008-11-01

    A three-dimensional nonlinear baroclinic model is used to model the circulation in the Ballenas Channel, Gulf of California, México, which was inferred from current meter observations over three sills that surround the area. The suggested circulation consists of deep inflow that follows two paths: the first one is a direct spill of water through San Lorenzo sill into Ballenas Channel, the second one, a larger route that starts at San Esteban sill, then flows north of the island passing over Tiburón and Delfín basins, and then turns to the south reaching the North Ballenas Channel sill and then spills into Ballenas Channel. Following the latter result, a previous modeling effort to reproduce the circulation was partially obtained, the long path was not reproduced and it was believed that finer horizontal resolution was needed. In this work, the bathymetric resolution was increased by a factor of three and the full path of this deep circulation is now obtained and corroborated.

  18. Gulf ring algae

    Science.gov (United States)

    Although they rank among the tiniest of the microspcopic phytoplankton, coccolithophore algae aid oceanographers studying the Gulf Stream rings and the ring boundaries. The algal group could help to identify more precisely the boundary of the warm rings of water that spin off from the Gulf Stream and become independent pools of warm water in the colder waters along the northeastern U.S. coast.Coccolithophore populations in the Gulf Stream rings intrigue oceanographers for two reasons: The phytoplankton are subjected to an environment that changes every few days, and population explosions within one coccolithophore species seem to be associated with changes in the characteristics of ocean water, said Pat Blackwelder, an associate professor at the Nova Oceanographic Center in Dania, Fla. She is one of many studying the physics, chemistry, and biology of warm core rings. A special oceanography session on these rings was held at the recent AGU Fall Meeting/ASLO Winter Meeting.

  19. Bioenergetic model estimates of interannual and spatial patterns in consumption demand and growth potential of juvenile pink salmon ( Oncorhynchus gorbuscha) in the Gulf of Alaska

    Science.gov (United States)

    Moss, Jamal H.; Beauchamp, David A.; Cross, Alison D.; Farley, Edward V.; Murphy, James M.; Helle, John H.; Walker, Robert V.; Myers, Katherine W.

    2009-12-01

    A bioenergetic model of juvenile pink salmon ( Oncorhynchus gorbuscha) was used to estimate daily prey consumption and growth potential of four ocean habitats in the Gulf of Alaska during 2001 and 2002. Growth potential was not significantly higher in 2002 than in 2001 at an alpha level of 0.05 ( P=0.073). Average differences in growth potential across habitats were minimal (slope habitat=0.844 g d -1, shelf habitat=0.806 g d -1, offshore habitat=0.820 g d -1, and nearshore habitat=0.703 g d -1) and not significantly different ( P=0.630). Consumption demand differed significantly between hatchery and wild stocks ( P=0.035) when examined within year due to the interaction between hatchery verses wild origin and year. However, the overall effect of origin across years was not significant ( P=0.705) due to similar total amounts of prey consumed by all juvenile pink salmon in both study years. We anticipated that years in which ocean survival was high would have had high growth potential, but this relationship did not prove to be true. Therefore, modeled growth potential may not be useful as a tool for forecasting survival of Prince William Sound hatchery pink salmon stocks. Significant differences in consumption demand and a two-fold difference in nearshore abundance during 2001 of hatchery and wild pink salmon confirmed the existence of strong and variable interannual competition and the importance of the nearshore region as being a potential competitive bottleneck.

  20. Bioenergetic model estimates of interannual and spatial patterns in consumption demand and growth potential of juvenile pink salmon (Oncorhynchus gorbuscha) in the Gulf of Alaska

    Science.gov (United States)

    Moss, J.H.; Beauchamp, D.A.; Cross, A.D.; Farley, E.V.; Murphy, J.M.; Helle, J.H.; Walker, R.V.; Myers, K.W.

    2009-01-01

    A bioenergetic model of juvenile pink salmon (Oncorhynchus gorbuscha) was used to estimate daily prey consumption and growth potential of four ocean habitats in the Gulf of Alaska during 2001 and 2002. Growth potential was not significantly higher in 2002 than in 2001 at an alpha level of 0.05 (P=0.073). Average differences in growth potential across habitats were minimal (slope habitat=0.844 g d-1, shelf habitat=0.806 g d-1, offshore habitat=0.820 g d-1, and nearshore habitat=0.703 g d-1) and not significantly different (P=0.630). Consumption demand differed significantly between hatchery and wild stocks (P=0.035) when examined within year due to the interaction between hatchery verses wild origin and year. However, the overall effect of origin across years was not significant (P=0.705) due to similar total amounts of prey consumed by all juvenile pink salmon in both study years. We anticipated that years in which ocean survival was high would have had high growth potential, but this relationship did not prove to be true. Therefore, modeled growth potential may not be useful as a tool for forecasting survival of Prince William Sound hatchery pink salmon stocks. Significant differences in consumption demand and a two-fold difference in nearshore abundance during 2001 of hatchery and wild pink salmon confirmed the existence of strong and variable interannual competition and the importance of the nearshore region as being a potential competitive bottleneck.

  1. A new model for the biodegradation kinetics of oil droplets: application to the Deepwater Horizon oil spill in the Gulf of Mexico.

    Science.gov (United States)

    Vilcáez, Javier; Li, Li; Hubbard, Susan S

    2013-10-20

    Oil biodegradation by native bacteria is one of the most important natural processes that can attenuate the environmental impacts of marine oil spills. Existing models for oil biodegradation kinetics are mostly for dissolved oil. This work developed a new mathematical model for the biodegradation of oil droplets and applied the model to estimate the time scale for oil biodegradation under conditions relevant to the Deepwater Horizon oil spill in the Gulf of Mexico. In the model, oil is composed of droplets of various sizes following the gamma function distribution. Each oil droplet shrinks during the microbe-mediated degradation at the oil-water interface. Using our developed model, we find that the degradation of oil droplets typically goes through two stages. The first stage is characterized by microbial activity unlimited by oil-water interface with higher biodegradation rates than that of the dissolved oil. The second stage is governed by the availability of the oil-water interface, which results in much slower rates than that of soluble oil. As a result, compared to that of the dissolved oil, the degradation of oil droplets typically starts faster and then quickly slows down, ultimately reaching a smaller percentage of degraded oil in longer time. The availability of the water-oil interface plays a key role in determining the rates and extent of degradation. We find that several parameters control biodegradation rates, including size distribution of oil droplets, initial microbial concentrations, initial oil concentration and composition. Under conditions relevant to the Deepwater Horizon spill, we find that the size distribution of oil droplets (mean and coefficient of variance) is the most important parameter because it determines the availability of the oil-water interface. Smaller oil droplets with larger variance leads to faster and larger extent of degradation. The developed model will be useful for evaluating transport and fate of spilled oil, different

  2. Revisiting the problem of the Gulf Stream separation: on the representation of topography in ocean models with different types of vertical grids

    Science.gov (United States)

    Ezer, Tal

    2016-08-01

    The difficulty of simulating a realistic Gulf Stream (GS) that separates from the coast at Cape Hatteras has troubled numerical ocean modelers for a long time, and the problem is evident in different models, from the early models of the 1980s to the modern models of today. The source of the problem is not completely understood yet, since GS simulations are sensitive to many different factors, such as numerical parameterization, model grid, treatment of topography and forcing fields. A curious result of early models is that models with terrain-following vertical grids (e.g., "sigma" or "s" coordinates) seem to achieve a better GS separation than z-level models of similar resolution, so the impact of the vertical grid type on GS simulations is revisited here. An idealized generalized coordinate numerical model is used to compare between a sigma-coordinate grid and a z-level grid while maintaining the same numerical code and model parameters. Short-term diagnostic-prognostic calculations focus on the initial dynamic adjustment of the GS from a given initial condition and imposed boundary conditions. In diagnostic calculations, wherein the three-dimensional flow field is adjusted to time-invariant temperature and salinity data, the GS is quite realistic independent of the grid type. However, when switching to prognostic calculations, the GS in the z-level model tends to immediately develop an unrealistic GS branch that continues along the continental slope instead of separating from the coast at Cape Hatteras. The GS is more realistic in either a sigma-coordinate model or in a z-level model with a vertical wall replacing the continental slope. Increasing the vertical resolution in the z-level model reduces numerical noise, but it does not solve the GS separation problem. Vorticity balance analysis shows that the Joint Effect of Baroclinicity and bottom Relief (JEBAR) and its associated bottom pressure torque are very sensitive to the choice of vertical grid. A stepped

  3. Application of SeaWIFS- and AVHRR-derived data for mesoscale and regional validation of a 3-D high-resolution physical biological model of the Gulf of St. Lawrence (Canada)

    Science.gov (United States)

    Le Fouest, V.; Zakardjian, B.; Saucier, F. J.; Çizmeli, S. A.

    2006-04-01

    We present here a first attempt to validate a regional three-dimensional (3-D) physical-biological coupled model of the Gulf of St. Lawrence with coincident Advanced Very High Resolution Radiometer (AVHRR)-derived sea surface temperature (SST) and Sea-viewing Wide Field-of-view Sensor (SeaWIFS)-derived Chlorophyll- a (Chl- a) data. The analysis focused on comparisons between remotely sensed data and simulated as well as in situ temperature, salinity, Chl- a, and nitrate. Results show that the simulated and AVHRR-derived fields of SST were qualitatively and quantitatively in agreement with in situ measurements. By contrast, marked differences were found between the simulated and SeaWIFS-derived fields of Chl- a, the latter comparing better with the freshwater-associated turbidity simulated by the model. Simulated temperature, salinity, nitrate, and Chl- a data compared well with coincident in situ measurements, and it is then suggested that freshwater-associated turbidity related to the river discharges largely contributed to the Chl- a retrievals by SeaWIFS in the Gulf's waters when using the standard OC4v.4 algorithm and atmospheric correction. Nevertheless, the striking agreement between SeaWIFS-derived ocean colour data and the simulated freshwater-associated turbidity allowed to validate the regional estuarine circulation and associated mesoscale variability. This result brings support to the model's ability to simulate realistic physical and biogeochemical fields in the Gulf of St. Lawrence.

  4. EAARL Coastal Topography - Northern Gulf of Mexico, 2007: First surface

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A first surface elevation map (also known as a Digital Elevation Model, or DEM) of the northern Gulf of Mexico barrier islands and Naval Live Oaks was produced from...

  5. EAARL Topography-Gulf Islands National Seashore-Florida

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Elevation maps (also known as Digital Elevation Models or DEMs) of Gulf Islands National Seashore were produced from remotely-sensed, geographically-referenced...

  6. Tides in the Gulf of Khambhat, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Nayak, R.K.; Shetye, S.R.

    Semi-diurnal tides in the Gulf of Khambhat (Cambay), west coast of India, amplify about threefold from mouth to head. In contrast, the amplification of diurnal tides is much smaller. A one-dimensional barotropic model with channel geometry...

  7. EAARL Topography-Gulf Islands National Seashore-Florida

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Elevation maps (also known as Digital Elevation Models or DEMs) of Gulf Islands National Seashore were produced from remotely-sensed, geographically-referenced...

  8. EAARL Topography-Gulf Islands National Seashore-Mississippi

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Abstract: Elevation maps (also known as Digital Elevation Models or DEMs) of Gulf Islands National Seashore were produced from remotely-sensed,...

  9. EAARL Coastal Topography - Northern Gulf of Mexico, 2007: Bare earth

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare earth elevation map (also known as a Digital Elevation Model, or DEM) of the northern Gulf of Mexico barrier islands and Naval Live Oaks was produced from...

  10. EAARL Topography-Gulf Islands National Seashore-Mississippi

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Abstract: Elevation maps (also known as Digital Elevation Models or DEMs) of Gulf Islands National Seashore were produced from remotely-sensed,...

  11. EAARL Coastal Topography - Northern Gulf of Mexico, 2007: First surface

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A first surface elevation map (also known as a Digital Elevation Model, or DEM) of the northern Gulf of Mexico barrier islands and Naval Live Oaks was produced from...

  12. EAARL Coastal Topography - Northern Gulf of Mexico, 2007: Bare earth

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A bare earth elevation map (also known as a Digital Elevation Model, or DEM) of the northern Gulf of Mexico barrier islands and Naval Live Oaks was produced from...

  13. Storm surge and wave simulations in the Gulf of Mexico using a consistent drag relation for atmospheric and storm surge models

    Directory of Open Access Journals (Sweden)

    D. Vatvani

    2012-07-01

    Full Text Available To simulate winds and water levels, numerical weather prediction (NWP and storm surge models generally use the traditional bulk relation for wind stress, which is characterized by a wind drag coefficient. A still commonly used drag coefficient in those models, some of them were developed in the past, is based on a relation, according to which the magnitude of the coefficient is either constant or increases monotonically with increasing surface wind speed (Bender, 2007; Kim et al., 2008; Kohno and Higaki, 2006. The NWP and surge models are often tuned independently from each other in order to obtain good results. Observations have indicated that the magnitude of the drag coefficient levels off at a wind speed of about 30 m s−1, and then decreases with further increase of the wind speed. Above a wind speed of approximately 30 m s−1, the stress above the air-sea interface starts to saturate. To represent the reducing and levelling off of the drag coefficient, the original Charnock drag formulation has been extended with a correction term.

    In line with the above, the Delft3D storm surge model is tested using both Charnock's and improved Makin's wind drag parameterization to evaluate the improvements on the storm surge model results, with and without inclusion of the wave effects. The effect of waves on storm surge is included by simultaneously simulating waves with the SWAN model on identical model grids in a coupled mode. However, the results presented here will focus on the storm surge results that include the wave effects.

    The runs were carried out in the Gulf of Mexico for Katrina and Ivan hurricane events. The storm surge model was initially forced with H*wind data (Powell et al., 2010 to test the effect of the Makin's wind drag parameterization on the storm surge model separately. The computed wind, water levels and waves are subsequently compared with observation data. Based on the good

  14. Using models of social transmission to examine the spread of longline depredation behavior among sperm whales in the Gulf of Alaska.

    Directory of Open Access Journals (Sweden)

    Zachary A Schakner

    Full Text Available Fishing, farming and ranching provide opportunities for predators to prey on resources concentrated by humans, a behavior termed depredation. In the Gulf of Alaska, observations of sperm whales depredating on fish caught on demersal longline gear dates back to the 1970s, with reported incidents increasing in the mid-1990s. Sperm whale depredation provides an opportunity to study the spread of a novel foraging behavior within a population. Data were collected during National Marine Fisheries Service longline surveys using demersal longline gear in waters off Alaska from 1998 to 2010. We evaluated whether observations of depredation fit predictions of social transmission by fitting the temporal and spatial spread of new observations of depredation to the Wave of Advance model. We found a significant, positive relationship between time and the distance of new observations from the diffusion center (r(2 = 0.55, p-value  = 0.003. The data provide circumstantial evidence for social transmission of depredation. We discuss how changes in human activities in the region (fishing methods and regulations have created a situation in which there is spatial-temporal overlap with foraging sperm whales, likely influencing when and how the behavior spread among the population.

  15. Using models of social transmission to examine the spread of longline depredation behavior among sperm whales in the Gulf of Alaska.

    Science.gov (United States)

    Schakner, Zachary A; Lunsford, Chris; Straley, Janice; Eguchi, Tomoharu; Mesnick, Sarah L

    2014-01-01

    Fishing, farming and ranching provide opportunities for predators to prey on resources concentrated by humans, a behavior termed depredation. In the Gulf of Alaska, observations of sperm whales depredating on fish caught on demersal longline gear dates back to the 1970s, with reported incidents increasing in the mid-1990s. Sperm whale depredation provides an opportunity to study the spread of a novel foraging behavior within a population. Data were collected during National Marine Fisheries Service longline surveys using demersal longline gear in waters off Alaska from 1998 to 2010. We evaluated whether observations of depredation fit predictions of social transmission by fitting the temporal and spatial spread of new observations of depredation to the Wave of Advance model. We found a significant, positive relationship between time and the distance of new observations from the diffusion center (r(2) = 0.55, p-value  = 0.003). The data provide circumstantial evidence for social transmission of depredation. We discuss how changes in human activities in the region (fishing methods and regulations) have created a situation in which there is spatial-temporal overlap with foraging sperm whales, likely influencing when and how the behavior spread among the population.

  16. Seasonal and Inter-annual Variability in Modeled Larval Dispersal and Population Connectivity of Blue Crabs (Callinectes sapidus) in the Northern Gulf of Mexico

    Science.gov (United States)

    Gyory, J.; Jones, B.; Ko, D. S.; Taylor, C.

    2016-02-01

    Larval dispersal trajectories and their resulting population connectivity patterns are known to be key drivers of population dynamics for many marine organisms. However, few studies to date have examined the temporal variability in population connectivity. Here, we model the larval dispersal and population connectivity of blue crabs in the northern Gulf of Mexico from 2003-2012 and use network analyses to understand how they vary over seasonal and inter-annual scales. We found that in all years, the Mississippi River Delta is a barrier to dispersal. Few larvae cross it and settle successfully. In some years (2004, 2007, 2008, and 2009), 1-2 locations (Adams Bay and Chandeleur Sound) had high (> 0.3) betweenness centrality. These locations are likely to be important for maintaining population connectivity in the region, since more than 30% of larval pathways are predicted to pass through them. Connectivity matrices suggest that some estuaries have consistently high larval retention rates. These include West Cote Blanche Bay, Chandeleur Sound, and, in some years, Pensacola Bay and Atchafalaya Bay. Within the spawning season, we observe a decline in average vertex degree and average source strength in every year. This suggests that seasonal declines in the strength of along-shore currents produce consistent reductions in population connectivity through the spawning season.

  17. Estimating natural mortality rates and simulating fishing scenarios for Gulf of Mexico red grouper (Epinephelus morio) using the ecosystem model OSMOSE-WFS

    Science.gov (United States)

    Grüss, Arnaud; Schirripa, Michael J.; Chagaris, David; Velez, Laure; Shin, Yunne-Jai; Verley, Philippe; Oliveros-Ramos, Ricardo; Ainsworth, Cameron H.

    2016-02-01

    The ecosystem model OSMOSE-WFS was employed to evaluate natural mortality rates and fishing scenarios for Gulf of Mexico (GOM) red grouper (Epinephelus morio). OSMOSE-WFS represents major high trophic level (HTL) groups of species of the West Florida Shelf, is forced by the biomass of plankton and benthos groups, and has a monthly time step. The present application of the model uses a recently developed 'stochastic mortality algorithm' to resolve the mortality processes of HTL groups. OSMOSE-WFS predictions suggest that the natural mortality rate of juveniles of GOM red grouper is high and essentially due to predation, while the bulk of the natural mortality of adult red grouper results from causes not represented in OSMOSE-WFS such as, presumably, red tides. These results were communicated to GOM red grouper stock assessments. Moreover, OSMOSE-WFS indicate that altering the fishing mortality of GOM red grouper may have no global impact on the biomass of the major prey of red grouper, due to the high complexity and high redundancy of the modeled system. By contrast, altering the fishing mortality of GOM red grouper may have a large impact on the biomass of its major competitors. Increasing the fishing mortality of red grouper would increase the biomass of major competitors, due to reduced competition for food. Conversely, decreasing the fishing mortality of red grouper would diminish the biomass of major competitors, due to increased predation pressure on the juveniles of the major competitors by red grouper. The fishing scenarios that we evaluated may have slightly different impacts in the real world, due to some discrepancies between the diets of red grouper and its major competitors predicted by OSMOSE-WFS and the observed ones. Modifications in OSMOSE-WFS are suggested to reduce these discrepancies.

  18. Assessment of resource selection models to predict occurrence of five juvenile flatfish species (Pleuronectidae) over the continental shelf in the western Gulf of Alaska

    Science.gov (United States)

    Wilson, Matthew T.; Mier, Kathryn L.; Cooper, Dan W.

    2016-05-01

    According to the nursery size hypothesis, flatfish recruitment is constrained by nursery area. Thus, if resource selection models can be shown to accurately predict the location and geographic extent of flatfish nursery areas, they will become important tools in the management and study of flatfish population dynamics. We demonstrate that some resource selection models derived previously to predict the presence and absence of juvenile flatfishes near shore were applicable to the broader continental shelf. For other age-species groups, derivation of new models for the continental shelf was necessary. Our study was conducted in the western Gulf of Alaska (GoA) during October 2011 on four groups of age-0 juvenile flatfishes: Pacific halibut (Hippoglossus stenolepis), arrowtooth flounder (Atheresthes stomias), northern rock sole (Lepidopsetta polyxystra), and flathead sole (Hippoglossoides elassodon); and three groups of age-1 juvenile flatfishes: northern rock sole, flathead sole, and yellowfin sole (Limanda aspera). Sampling occurred at 33 sites across the continental shelf. Fish were collected using a 3-m beam trawl, and a midwater trawl. Environmental data were collected on sediment composition and water temperature and depth. Many of the age-species groups co-occurred in the Shumagin and Barnabus sea valleys; however, age-0 arrowtooth flounder occurred at more locations than other juveniles, perhaps due to a relatively broad tolerance of environmental conditions and to the utilization of midwater habitat. Thus, the large nursery area of arrowtooth flounder may be one reason why they are currently the most abundant GoA flatfish. In fact, among all species, mean recruitment at age 3 increased with the percent occurrence of age-0 juveniles at the 33 sites, a proxy for relative nursery area, in accordance with the nursery size hypothesis, suggesting that mean recruitment among GoA flatfishes is structured by nursery size.

  19. INTEGRATED GEOLOGIC-ENGINEERING MODEL FOR REEF AND CARBONATE SHOAL RESERVOIRS ASSOCIATED WITH PALEOHIGHS: UPPER JURASSIC SMACKOVER FORMATION, NORTHEASTERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2002-09-25

    The University of Alabama in cooperation with Texas A&M University, McGill University, Longleaf Energy Group, Strago Petroleum Corporation, and Paramount Petroleum Company are undertaking an integrated, interdisciplinary geoscientific and engineering research project. The project is designed to characterize and model reservoir architecture, pore systems and rock-fluid interactions at the pore to field scale in Upper Jurassic Smackover reef and carbonate shoal reservoirs associated with varying degrees of relief on pre-Mesozoic basement paleohighs in the northeastern Gulf of Mexico. The project effort includes the prediction of fluid flow in carbonate reservoirs through reservoir simulation modeling which utilizes geologic reservoir characterization and modeling and the prediction of carbonate reservoir architecture, heterogeneity and quality through seismic imaging. The primary objective of the project is to increase the profitability, producibility and efficiency of recovery of oil from existing and undiscovered Upper Jurassic fields characterized by reef and carbonate shoals associated with pre-Mesozoic basement paleohighs. The principal research effort for Year 2 of the project has been reservoir characterization, 3-D modeling and technology transfer. This effort has included six tasks: (1) the study of rockfluid interactions, (2) petrophysical and engineering characterization, (3) data integration, (4) 3-D geologic modeling, (5) 3-D reservoir simulation and (6) technology transfer. This work was scheduled for completion in Year 2. Overall, the project work is on schedule. Geoscientific reservoir characterization is essentially completed. The architecture, porosity types and heterogeneity of the reef and shoal reservoirs at Appleton and Vocation Fields have been characterized using geological and geophysical data. The study of rock-fluid interactions is near completion. Observations regarding the diagenetic processes influencing pore system development and

  20. Population Structure, Abundance and Movement of Whale Sharks in the Arabian Gulf and the Gulf of Oman

    Science.gov (United States)

    Robinson, David P.; Jaidah, Mohammed Y.; Bach, Steffen; Lee, Katie; Jabado, Rima W.; Rohner, Christoph A.; March, Abi; Caprodossi, Simone; Henderson, Aaron C.; Mair, James M.; Ormond, Rupert; Pierce, Simon J.

    2016-01-01

    Data on the occurrence of whale sharks, Rhincodon typus, in the Arabian Gulf and Gulf of Oman were collected by dedicated boat surveys and via a public-sightings scheme during the period from 2011 to 2014. A total of 422 individual whale sharks were photo-identified from the Arabian Gulf and the northern Gulf of Oman during that period. The majority of sharks (81%, n = 341) were encountered at the Al Shaheen area of Qatar, 90 km off the coast, with the Musandam region of Oman a secondary area of interest. At Al Shaheen, there were significantly more male sharks (n = 171) than females (n = 78; X2 = 17.52, P 9 m individuals were visually assessed as pregnant. Connectivity among sharks sighted in Qatari, Omani and UAE waters was confirmed by individual spot pattern matches. A total of 13 identified sharks were re-sighted at locations other than that at which they were first sighted, including movements into and out of the Arabian Gulf through the Strait of Hormuz. Maximum likelihood techniques were used to model an estimated combined population for the Arabian Gulf and Gulf of Oman of 2837 sharks ± 1243.91 S.E. (95% C.I. 1720–6295). The Al Shaheen aggregation is thus the first site described as being dominated by mature males while the free-swimming pregnant females are the first reported from the Indian Ocean. PMID:27362839

  1. Wind Simulations for the Gulf of Suez with KAMM

    DEFF Research Database (Denmark)

    Frank, Helmut Paul

    In order to get a better overview of the spatial distribution of the wind resource in the Gulf of Suez, numerical simulations to determine the wind climate have been carried out with the Karlsruhe Atmospheric Mesoscale Model KAMM. The method and the results are described here. The simulations of ...... of the wind climate of the Gulf of Suez with KAMM capture the main features of the observed wind climate. The mean wind speed and energy flux density are somewhat underpredicted....

  2. Hurricane Risk Variability along the Gulf of Mexico Coastline

    OpenAIRE

    Jill C Trepanier; Ellis, Kelsey N.; Clay S Tucker

    2015-01-01

    Hurricane risk characteristics are examined across the U. S. Gulf of Mexico coastline using a hexagonal tessellation. Using an extreme value model, parameters are collected representing the rate or λ (frequency), the scale or σ (range), and the shape or ξ (intensity) of the extreme wind distribution. These latent parameters and the 30-year return level are visualized across the grid. The greatest 30-year return levels are located toward the center of the Gulf of Mexico, and for inland locatio...

  3. 3D crustal seismic velocity model for the Gulf of Cadiz and adjacent areas (SW Iberia margin) based on seismic reflection and refraction profiles

    Science.gov (United States)

    Lozano, Lucía; Cantavella, Juan Vicente; Barco, Jaime; Carranza, Marta; Burforn, Elisa

    2016-04-01

    The Atlantic margin of the SW Iberian Peninsula and northern Morocco has been subject of study during the last 30 years. Many seismic reflection and refraction profiles have been carried out offshore, providing detailed information about the crustal structure of the main seafloor tectonic domains in the region, from the South Portuguese Zone and the Gulf of Cadiz to the Abyssal Plains and the Josephine Seamount. The interest to obtain a detailed and realistic velocity model for this area, integrating the available data from these studies, is clear, mainly to improve real-time earthquake hypocentral location and for tsunami and earthquake early warning. Since currently real-time seismic location tools allow the implementation of 3D velocity models, we aim to generate a full 3D crustal model. For this purpose we have reviewed more than 50 profiles obtained in different seismic surveys, from 1980 to 2008. Data from the most relevant and reliable 2D seismic velocity published profiles were retrieved. We first generated a Moho depth map of the studied area (latitude 32°N - 41°N and longitude 15°W - 5°W) by extracting Moho depths along each digitized profile with a 10 km spacing, and then interpolating this dataset using ordinary kriging method and generating the contour isodepth map. Then, a 3D crustal velocity model has been obtained. Selected vertical sections at different distances along each profile were considered to retrieve P-wave velocity values at each interface in order to reproduce the geometry and the velocity gradient within each layer. A double linear interpolation, both in distance and depth, with sampling rates of 10 km and 1 km respectively, was carried out to generate a (latitude, longitude, depth, velocity) matrix. This database of all the profiles was interpolated to obtain the P-wave velocity distribution map every kilometer of depth. The new 3D velocity model has been integrated in NonLinLoc location program to relocate several representative

  4. Conceptualization of a fresh groundwater lens influenced by climate change: A modeling study of an arid-region island in the Persian Gulf, Iran

    Science.gov (United States)

    Mahmoodzadeh, Davood; Ketabchi, Hamed; Ataie-Ashtiani, Behzad; Simmons, Craig T.

    2014-11-01

    Understanding the fresh groundwater lens (FGL) behavior and potential threat of climatic-induced seawater intrusion (SWI) are significant for the future water resources management of many small islands. In this paper, the FGL of Kish Island, an arid-region case in the Persian Gulf, Iran, is modeled using two-dimensional (2D) and three-dimensional (3D) simulations. These simulations are based on the application of SUTRA, a density-dependent groundwater numerical model. Also, the numerical model parameters are calibrated using PEST, an automated parameter estimation code. Firstly a detailed conceptualization of the FGL model is completed to understand the sensitivity of the FGL to some particular aspects of the model prior to analysis of climate change simulations. For these investigations, the FGL system is defined based on Kish Island system to accomplish the integrated comparison of features of a conceptual model that are representative of real-world systems. This is the first study which adopts such an approach. The comparison of cross-sectional simulations suggests that the two-layer properties of the Kish Island aquifer have a significant influence on the FGL while the impacts of lateral-boundary irregularities are negligible. The impacts of sea-level rise (SLR), associated land-surface inundation (LSI), and variations in recharge rate on the FGL salinization of Kish Island are investigated numerically. Variations of SLR value (1-4 m) and net recharge rate (17-24 mm/year) are considered to cover a possible range of climatic scenarios in this arid-region island. The 2D and 3D simulation results demonstrate that LSI caused by SLR and recharge rate variation impacts are more important factors in the FGL in comparison to estimated SLR impacts without LSI. It is also shown that climate change impacts on the FGL are long-term to reach a new FGL equilibrium in the case of Kish Island's aquifer system. The comparative analysis of 2D and 3D results shows that three

  5. Beyond the Gulf Metropolises

    DEFF Research Database (Denmark)

    Wippel, Steffen

    2013-01-01

    The extended studies on urbanisation in the Gulf region that came up in the early 2000s concentrated on the main centres with their worldwide-admired mega-projects and branding strategies. Only rather recently did a more general interest arise in the second-tier range of Gulf cities, which also......, which started in the late 1990s. After a short review of the city‘s development until the 1980s, this paper will also present its current urban and economic evolution. Then it will turn to the globalisation of Salalah in the context of national post-oil strategies, and study the physical fragmentation...... of the urban landscape. Finally, it will point to the shift from overall structural planning to individual master plans, and discuss the marketing of the new Salalah versus the selective conservation of the old....

  6. Biogenic carbon flows through the planktonic food web of the Amundsen Gulf (Arctic Ocean): A synthesis of field measurements and inverse modeling analyses

    Science.gov (United States)

    Forest, Alexandre; Tremblay, Jean-Éric; Gratton, Yves; Martin, Johannie; Gagnon, Jonathan; Darnis, Gérald; Sampei, Makoto; Fortier, Louis; Ardyna, Mathieu; Gosselin, Michel; Hattori, Hiroshi; Nguyen, Dan; Maranger, Roxane; Vaqué, Dolors; Marrasé, Cèlia; Pedrós-Alió, Carlos; Sallon, Amélie; Michel, Christine; Kellogg, Colleen; Deming, Jody; Shadwick, Elizabeth; Thomas, Helmuth; Link, Heike; Archambault, Philippe; Piepenburg, Dieter

    2011-12-01

    Major pathways of biogenic carbon (C) flow are resolved for the planktonic food web of the flaw lead polynya system of the Amundsen Gulf (southeast Beaufort Sea, Arctic Ocean) in spring-summer 2008. This period was relevant to study the effect of climate change on Arctic marine ecosystems as it was characterized by unusually low ice cover and warm sea surface temperature. Our synthesis relied on a mass balance estimate of gross primary production (GPP) of 52.5 ± 12.5 g C m -2 calculated using the drawdown of nitrate and dissolved inorganic C, and a seasonal f-ratio of 0.64. Based on chlorophyll a biomass, we estimated that GPP was dominated by phytoplankton (93.6%) over ice algae (6.4%) and by large cells (>5 μm, 67.6%) over small cells (production, zooplankton biomass and respiration, herbivory, bacterivory, vertical particle fluxes, pools of particulate and dissolved organic carbon (POC, DOC), net community production (NCP), as well as selected variables from the literature were used to evaluate the fate of size-fractionated GPP in the ecosystem. The structure and functioning of the planktonic food web was elucidated through inverse analysis using the mean GPP and the 95% confidence limits of every other field measurement as lower and upper constraints. The model computed a net primary production of 49.2 g C m -2, which was directly channeled toward dominant calanoid copepods (i.e. Calanus hyperboreus 20%, Calanus glacialis 10%, and Metridia longa 10%), other mesozooplankton (12%), microzooplankton (14%), detrital POC (18%), and DOC (16%). Bacteria required 29.9 g C m -2, a demand met entirely by the DOC derived from local biological activities. The ultimate C outflow comprised respiration fluxes (82% of the initial GPP), a small sedimentation (3%), and a modest residual C flow (15%) resulting from NCP, dilution and accumulation. The sinking C flux at the model limit depth (395 m) supplied 60% of the estimated benthic C demand (2.8 g C m -2), suggesting that

  7. Variational data assimilation for limited-area models: solution of the open boundary control problem and its application for the Gulf of Finland

    Science.gov (United States)

    Sheloput, Tatiana; Agoshkov, Valery

    2017-04-01

    The problem of modeling water areas with `liquid' (open) lateral boundaries is discussed. There are different known methods dealing with open boundaries in limited-area models, and one of the most efficient is data assimilation. Although this method is popular, there are not so many articles concerning its implementation for recovering boundary functions. However, the problem of specifying boundary conditions at the open boundary of a limited area is still actual and important. The mathematical model of the Baltic Sea circulation, developed in INM RAS, is considered. It is based on the system of thermo-hydrodynamic equations in the Boussinesq and hydrostatic approximations. The splitting method that is used for time approximation in the model allows to consider the data assimilation problem as a sequence of linear problems. One of such `simple' temperature (salinity) assimilation problem is investigated in the study. Using well known techniques of study and solution of inverse problems and optimal control problems [1], we propose an iterative solution algorithm and we obtain conditions for existence of the solution, for unique and dense solvability of the problem and for convergence of the iterative algorithm. The investigation shows that if observations satisfy certain conditions, the proposed algorithm converges to the solution of the boundary control problem. Particularly, it converges when observational data are given on the `liquid' boundary [2]. Theoretical results are confirmed by the results of numerical experiments. The numerical algorithm was implemented to water area of the Baltic Sea. Two numerical experiments were carried out in the Gulf of Finland: one with the application of the assimilation procedure and the other without. The analyses have shown that the surface temperature field in the first experiment is close to the observed one, while the result of the second experiment misfits. Number of iterations depends on the regularisation parameter, but

  8. INTEGRATED GEOLOGIC-ENGINEERING MODEL FOR REEF AND CARBONATE SHOAL RESERVOIRS ASSOCIATED WITH PALEOHIGHS: UPPER JURASSIC SMACKOVER FORMATION, NORTHEASTERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2003-09-25

    The University of Alabama in cooperation with Texas A&M University, McGill University, Longleaf Energy Group, Strago Petroleum Corporation, and Paramount Petroleum Company are undertaking an integrated, interdisciplinary geoscientific and engineering research project. The project is designed to characterize and model reservoir architecture, pore systems and rock-fluid interactions at the pore to field scale in Upper Jurassic Smackover reef and carbonate shoal reservoirs associated with varying degrees of relief on pre-Mesozoic basement paleohighs in the northeastern Gulf of Mexico. The project effort includes the prediction of fluid flow in carbonate reservoirs through reservoir simulation modeling that utilizes geologic reservoir characterization and modeling and the prediction of carbonate reservoir architecture, heterogeneity and quality through seismic imaging. The primary objective of the project is to increase the profitability, producibility and efficiency of recovery of oil from existing and undiscovered Upper Jurassic fields characterized by reef and carbonate shoals associated with pre-Mesozoic basement paleohighs. The principal research effort for Year 3 of the project has been reservoir characterization, 3-D modeling, testing of the geologic-engineering model, and technology transfer. This effort has included six tasks: (1) the study of seismic attributes, (2) petrophysical characterization, (3) data integration, (4) the building of the geologic-engineering model, (5) the testing of the geologic-engineering model and (6) technology transfer. This work was scheduled for completion in Year 3. Progress on the project is as follows: geoscientific reservoir characterization is completed. The architecture, porosity types and heterogeneity of the reef and shoal reservoirs at Appleton and Vocation Fields have been characterized using geological and geophysical data. The study of rock-fluid interactions has been completed. Observations regarding the diagenetic

  9. The role of the Gulf Stream in European climate.

    Science.gov (United States)

    Palter, Jaime B

    2015-01-01

    The Gulf Stream carries the warm, poleward return flow of the wind-driven North Atlantic subtropical gyre and the Atlantic Meridional Overturning Circulation. This northward flow drives a significant meridional heat transport. Various lines of evidence suggest that Gulf Stream heat transport profoundly influences the climate of the entire Northern Hemisphere and, thus, Europe's climate on timescales of decades and longer. The Gulf Stream's influence is mediated through feedback processes between the ocean, atmosphere, and cryosphere. This review synthesizes paleoclimate archives, model simulations, and the instrumental record, which collectively suggest that decadal and longer-scale variability of the Gulf Stream's heat transport manifests in changes in European temperature, precipitation, and storminess. Given that anthropogenic climate change is projected to weaken the Atlantic Meridional Overturning Circulation, associated changes in European climate are expected. However, large uncertainty in the magnitude of the anticipated weakening undermines the predictability of the future climate in Europe.

  10. Estimation of carrying capacity of the Gulf of Kachchh, west coast of India in relation to petroleum hydrocarbon through oil spill modeling

    Digital Repository Service at National Institute of Oceanography (India)

    Vethamony, P.; Babu, M.T.; Reddy, G.S.; Sudheesh, K.; Desa, E.; Zingde, M.D.

    The Gulf of Kachchh (GoK) is a semi-enclosed basin located in the northern part of the west coast of India, and opens to the Arabian Sea. GoK is about 170 km long and 75 km wide at the mouth, and encompasses several ecosystems. Besides major...

  11. Sediment distribution study in the Gulf of Kachchh, India, from 3D hydrodynamic model simulation and satellite data

    Digital Repository Service at National Institute of Oceanography (India)

    Kunte, P.D.; Zhao, C.; Osawa, T.; Sugimori, Y.

    temperatures also exist in the middle part. The detailed structures of sea surface temperatures differ as satellites measure the skin temperature of water the body, whereas the model considers the entire first layer. The river discharge effect is not clearly...

  12. BASIN ANALYSIS AND PETROLEUM SYSTEM CHARACTERIZATION AND MODELING, INTERIOR SALT BASINS, CENTRAL AND EASTERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini; Donald A. Goddard

    2005-08-01

    The principal research effort for Year 3 of the project is basin modeling and petroleum system identification, comparative basin evaluation and resource assessment. In the first six (6) months of Year 3, the research focus is on basin modeling and petroleum system identification and the remainder of the year the emphasis is on the comparative basin evaluation and resource assessment. No major problems have been encountered to date, and the project is on schedule.

  13. INTEGRATED GEOLOGIC-ENGINEERING MODEL FOR REEF AND CARBONATE SHOAL RESERVOIRS ASSOCIATED WITH PALEOHIGHS: UPPER JURASSIC SMACKOVER FORMATION, NORTHEASTERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2001-09-14

    The University of Alabama in cooperation with Texas A&M University, McGill University, Longleaf Energy Group, Strago Petroleum Corporation, and Paramount Petroleum Company are undertaking an integrated, interdisciplinary geoscientific and engineering research project. The project is designed to characterize and model reservoir architecture, pore systems and rock-fluid interactions at the pore to field scale in Upper Jurassic Smackover reef and carbonate shoal reservoirs associated with varying degrees of relief on pre-Mesozoic basement paleohighs in the northeastern Gulf of Mexico. The project effort includes the prediction of fluid flow in carbonate reservoirs through reservoir simulation modeling which utilizes geologic reservoir characterization and modeling and the prediction of carbonate reservoir architecture, heterogeneity and quality through seismic imaging. The primary objective of the project is to increase the profitability, producibility and efficiency of recovery of oil from existing and undiscovered Upper Jurassic fields characterized by reef and carbonate shoals associated with pre-Mesozoic basement paleohighs. The principal research effort for Year 1 of the project has been reservoir description and characterization. This effort has included four tasks: (1) geoscientific reservoir characterization, (2) the study of rock-fluid interactions, (3) petrophysical and engineering characterization and (4) data integration. This work was scheduled for completion in Year 1. Overall, the project work is on schedule. Geoscientific reservoir characterization is essentially completed. The architecture, porosity types and heterogeneity of the reef and shoal reservoirs at Appleton and Vocation Fields have been characterized using geological and geophysical data. The study of rock-fluid interactions has been initiated. Observations regarding the diagenetic processes influencing pore system development and heterogeneity in these reef and shoal reservoirs have been

  14. Basin Analysis and Petroleum System Characterization and Modeling, Interior Salt Basins, Central and Eastern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini; Paul Aharon; Donald A. Goddard; Roger Barnaby

    2006-02-28

    The principal research effort for Year 3 of the project is basin modeling and petroleum system identification, comparative basin evaluation and resource assessment. In the first six (6) months of Year 3, the research focus is on basin modeling and petroleum system identification and the remainder of the year the emphasis is on the comparative basin evaluation and resource assessment. No major problems have been encountered to date, and the project is on schedule. The principal objectives of the project are to develop through basin analysis and modeling the concept that petroleum systems acting in a basin can be identified through basin modeling and to demonstrate that the information and analysis resulting from characterizing and modeling of these petroleum systems in the North Louisiana Salt Basin and the Mississippi Interior Salt Basin can be used in providing a more reliable and advanced approach for targeting stratigraphic traps and specific reservoir facies within a geologic system and in providing a refined assessment of undiscovered and underdeveloped reservoirs and associated oil and gas resources.

  15. BASIN ANALYSIS AND PETROLEUM SYSTEM CHARACTERIZATION AND MODELING, INTERIOR SALT BASINS, CENTRAL AND EASTERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2004-11-05

    The principal research effort for Year 2 of the project is the determination of the burial and thermal maturation histories and basin modeling and petroleum system identification of the North Louisiana Salt Basin. In the first six (6) to nine (9) months of Year 2, the research focus is on the determination of the burial and thermal maturation histories and the remainder of the year the emphasis is on basin modeling and petroleum system identification. No major problems have been encountered to date, and the project is on schedule.

  16. Basin Analysis and Petroleum System Characterization and Modeling, Interior Salt Basins, Central and Eastern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2006-07-31

    The principal research effort for Year 1 of Phase 2 (Concept Demonstration) of the project is Smackover petroleum system characterization and modeling. The necessary software applications are in the process of being acquired to accomplish this work. No major problems have been encountered to date, and the project is on schedule.

  17. Basin Analysis and Petroleum System Characterization and Modeling, Interior Salt Basins, Central and Eastern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2007-06-30

    The principal research effort for Year 2 of Phase 2 (Concept Demonstration) of the project is Mesozoic (Bossier) petroleum system characterization and modeling and refined resource assessment. The necessary software applications have been acquired to accomplish this work. No major problems have been encountered to date, and the project is on schedule.

  18. Basin Analysis and Petroleum System Characterization and Modelling, Interior Salt Basins, Central and Eastern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2006-09-30

    The principal research effort for Year 1 of Phase 2 (Concept Demonstration) of the project is Smackover petroleum system characterization and modeling. The necessary software applications have been acquired to accomplish this work. No major problems have been encountered to date, and the project is on schedule.

  19. Basin Analysis and Petroleum System Characterization and Modeling, Interior Salt Basins, Central and Eastern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2006-12-31

    The principal research effort for Year 1 of Phase 2 (Concept Demonstration) of the project is Smackover petroleum system characterization and modeling. The necessary software applications have been acquired to accomplish this work. No major problems have been encountered to date, and the project is on schedule.

  20. Gulf of Mexico Regional Collaborative Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Judd, Kathleen S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Judd, Chaeli [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Engel-Cox, Jill A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Gulbransen, Thomas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Anderson, Michael G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Woodruff, Dana L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Thom, Ronald M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Guzy, Michael [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hardin, Danny [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Estes, Maury [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2007-12-01

    This report presents the results of the Gulf of Mexico Regional Collaborative (GoMRC), a year-long project funded by NASA. The GoMRC project was organized around end user outreach activities, a science applications team, and a team for information technology (IT) development. Key outcomes are summarized below for each of these areas. End User Outreach; Successfully engaged federal and state end users in project planning and feedback; With end user input, defined needs and system functional requirements; Conducted demonstration to End User Advisory Committee on July 9, 2007 and presented at Gulf of Mexico Alliance (GOMA) meeting of Habitat Identification committee; Conducted significant engagement of other end user groups, such as the National Estuary Programs (NEP), in the Fall of 2007; Established partnership with SERVIR and Harmful Algal Blooms Observing System (HABSOS) programs and initiated plan to extend HABs monitoring and prediction capabilities to the southern Gulf; Established a science and technology working group with Mexican institutions centered in the State of Veracruz. Key team members include the Federal Commission for the Protection Against Sanitary Risks (COFEPRIS), the Ecological Institute (INECOL) a unit of the National Council for science and technology (CONACYT), the Veracruz Aquarium (NOAA’s first international Coastal Ecology Learning Center) and the State of Veracruz. The Mexican Navy (critical to coastal studies in the Southern Gulf) and other national and regional entities have also been engaged; and Training on use of SERVIR portal planned for Fall 2007 in Veracruz, Mexico Science Applications; Worked with regional scientists to produce conceptual models of submerged aquatic vegetation (SAV) ecosystems; Built a logical framework and tool for ontological modeling of SAV and HABs; Created online guidance for SAV restoration planning; Created model runs which link potential future land use trends, runoff and SAV viability; Analyzed SAV

  1. NASA Gulf of Mexico Initiative Hypoxia Research

    Science.gov (United States)

    Armstrong, Curtis D.

    2012-01-01

    The Applied Science & Technology Project Office at Stennis Space Center (SSC) manages NASA's Gulf of Mexico Initiative (GOMI). Addressing short-term crises and long-term issues, GOMI participants seek to understand the environment using remote sensing, in-situ observations, laboratory analyses, field observations and computational models. New capabilities are transferred to end-users to help them make informed decisions. Some GOMI activities of interest to the hypoxia research community are highlighted.

  2. Multi-Species Models of Time-Varying Catchability in the U.S. Gulf of Mexico

    OpenAIRE

    2009-01-01

    The catchability coefficient is used in most marine stock assessment models, and is usually assumed to be stationary and density-independent. However, recent research has shown that these assumptions are violated in most fisheries. Violation of these assumptions will cause underestimation of stock declines or recoveries, leading to inappropriate management policies. This project assesses the soundness of stationarity and density independence assumptions using multi-species data for seven s...

  3. Some Observational and Modeling Studies of the Atmospheric Boundary Layer at Mississippi Gulf Coast for Air Pollution Dispersion Assessment

    Directory of Open Access Journals (Sweden)

    Anjaneyulu Yerramilli

    2008-12-01

    Full Text Available Coastal atmospheric conditions widely vary from those over inland due to the land-sea interface, temperature contrast and the consequent development of local circulations. In this study a field meteorological experiment was conducted to measure vertical structure of boundary layer during the period 25-29 June, 2007 at three locations Seabee base, Harrison and Wiggins sites in the Mississippi coast. A GPS Sonde along with slow ascent helium balloon and automated weather stations equipped with slow and fast response sensors were used in the experiment. GPS sonde were launched at three specific times (0700 LT, 1300 LT and 1800 LT during the experiment days. The observations indicate shallow boundary layer near the coast which gradually develops inland. The weather research and forecasting (WRF meso-scale atmospheric model and a Lagrangian particle dispersion model (HYSPLIT are used to simulate the lower atmospheric flow and dispersion in a range of 100 km from the coast for 28-30 June, 2007. The simulated meteorological parameters were compared with the experimental observations. The meso-scale model results show significant temporal and spatial variations in the meteorological fields as a result of development of sea breeze flow, its coupling with the large scale flow field and the ensuing alteration in the mixing depth across the coast. Simulated ground-level concentrations of SO2 from four elevated point sources located along the coast indicate diurnal variation and impact of the local sea-land breeze on the direction of the plume. Model concentration levels were highest during the stable morning condition and during the sea-breeze time in the afternoon. The highest concentrations were found up to 40 km inland during sea breeze time. The study illustrates the application of field meteorological observations for the validation of WRF which is coupled to HYSPLIT for dispersion assessment in the coastal region.

  4. INTEGRATED GEOLOGIC-ENGINEERING MODEL FOR REEF AND CARBONATE SHOAL RESERVOIRS ASSOCIATED WITH PALEOHIGHS: UPPER JURASSIC SMACKOVER FORMATION, NORTHEASTERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2004-02-25

    The University of Alabama, in cooperation with Texas A&M University, McGill University, Longleaf Energy Group, Strago Petroleum Corporation, and Paramount Petroleum Company, has undertaken an integrated, interdisciplinary geoscientific and engineering research project. The project is designed to characterize and model reservoir architecture, pore systems and rock-fluid interactions at the pore to field scale in Upper Jurassic Smackover reef and carbonate shoal reservoirs associated with varying degrees of relief on pre-Mesozoic basement paleohighs in the northeastern Gulf of Mexico. The project effort includes the prediction of fluid flow in carbonate reservoirs through reservoir simulation modeling which utilizes geologic reservoir characterization and modeling and the prediction of carbonate reservoir architecture, heterogeneity and quality through seismic imaging. The primary goal of the project is to increase the profitability, producibility and efficiency of recovery of oil from existing and undiscovered Upper Jurassic fields characterized by reef and carbonate shoals associated with pre-Mesozoic basement paleohighs. Geoscientific reservoir property, geophysical seismic attribute, petrophysical property, and engineering property characterization has shown that reef (thrombolite) and shoal reservoir lithofacies developed on the flanks of high-relief crystalline basement paleohighs (Vocation Field example) and on the crest and flanks of low-relief crystalline basement paleohighs (Appleton Field example). The reef thrombolite lithofacies have higher reservoir quality than the shoal lithofacies due to overall higher permeabilities and greater interconnectivity. Thrombolite dolostone flow units, which are dominated by dolomite intercrystalline and vuggy pores, are characterized by a pore system comprised of a higher percentage of large-sized pores and larger pore throats. Rock-fluid interactions (diagenesis) studies have shown that although the primary control on

  5. Influence of the Gulf Stream on the troposphere.

    Science.gov (United States)

    Minobe, Shoshiro; Kuwano-Yoshida, Akira; Komori, Nobumasa; Xie, Shang-Ping; Small, Richard Justin

    2008-03-13

    The Gulf Stream transports large amounts of heat from the tropics to middle and high latitudes, and thereby affects weather phenomena such as cyclogenesis and low cloud formation. But its climatic influence, on monthly and longer timescales, remains poorly understood. In particular, it is unclear how the warm current affects the free atmosphere above the marine atmospheric boundary layer. Here we consider the Gulf Stream's influence on the troposphere, using a combination of operational weather analyses, satellite observations and an atmospheric general circulation model. Our results reveal that the Gulf Stream affects the entire troposphere. In the marine boundary layer, atmospheric pressure adjustments to sharp sea surface temperature gradients lead to surface wind convergence, which anchors a narrow band of precipitation along the Gulf Stream. In this rain band, upward motion and cloud formation extend into the upper troposphere, as corroborated by the frequent occurrence of very low cloud-top temperatures. These mechanisms provide a pathway by which the Gulf Stream can affect the atmosphere locally, and possibly also in remote regions by forcing planetary waves. The identification of this pathway may have implications for our understanding of the processes involved in climate change, because the Gulf Stream is the upper limb of the Atlantic meridional overturning circulation, which has varied in strength in the past and is predicted to weaken in response to human-induced global warming in the future.

  6. BASIN ANALYSIS AND PETROLEUM SYSTEM CHARACTERIZATION AND MODELING, INTERIOR SALT BASINS, CENTRAL AND EASTERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini; Donald A. Goddard; Ronald K. Zimmerman

    2005-05-10

    The principal research effort for Year 2 of the project has been data compilation and the determination of the burial and thermal maturation histories of the North Louisiana Salt Basin and basin modeling and petroleum system identification. In the first nine (9) months of Year 2, the research focus was on the determination of the burial and thermal maturation histories, and during the remainder of the year the emphasis has basin modeling and petroleum system identification. Existing information on the North Louisiana Salt Basin has been evaluated, an electronic database has been developed, regional cross sections have been prepared, structure and isopach maps have been constructed, and burial history, thermal maturation history and hydrocarbon expulsion profiles have been prepared. Seismic data, cross sections, subsurface maps and related profiles have been used in evaluating the tectonic, depositional, burial and thermal maturation histories of the basin. Oil and gas reservoirs have been found to be associated with salt-supported anticlinal and domal features (salt pillows, turtle structures and piercement domes); with normal faulting associated with the northern basin margin and listric down-to-the-basin faults (state-line fault complex) and faulted salt features; and with combination structural and stratigraphic features (Sabine and Monroe Uplifts) and monoclinal features with lithologic variations. Petroleum reservoirs are mainly Upper Jurassic and Lower Cretaceous fluvial-deltaic sandstone facies and Lower Cretaceous and Upper Cretaceous shoreline, marine bar and shallow shelf sandstone facies. Cretaceous unconformities significantly contribute to the hydrocarbon trapping mechanism capacity in the North Louisiana Salt Basin. The chief petroleum source rock in this basin is Upper Jurassic Smackover lime mudstone beds. The generation of hydrocarbons from Smackover lime mudstone was initiated during the Early Cretaceous and continued into the Tertiary

  7. Engineering and environmental remediation scenarios due to leakage from the Gulf War oil spill using 3-D numerical contaminant modellings

    Science.gov (United States)

    Yihdego, Yohannes; Al-Weshah, Radwan A.

    2016-12-01

    The transport groundwater modelling has been undertaken to assess potential remediation scenarios and provide an optimal remediation options for consideration. The purpose of the study was to allow 50 years of predictive remediation simulation time. The results depict the likely total petroleum hydrocarbon migration pattern in the area under the worst-case scenario. The remediation scenario simulations indicate that do nothing approach will likely not achieve the target water quality within 50 years. Similarly, complete source removal approach will also likely not achieve the target water quality within 50 years. Partial source removal could be expected to remove a significant portion of the contaminant mass, but would increase the rate of contaminant recharge in the short to medium term. The pump-treat-reinject simulation indicates that the option appears feasible and could achieve a reduction in the area of the 0.01 mg/L TPH contour area for both Raudhatain and Umm Al-Aish by 35 and 30%, respectively, within 50 years. The rate of improvement and the completion date would depend on a range of factors such as bore field arrangements, pumping rates, reinjection water quality and additional volumes being introduced and require further optimisation and field pilot trials.

  8. Physical and Bio-Optical Processes in the Gulf of Mexico -- Linking Real-Time Circulation Models and Satellite Bio-Optical and SST Properties

    Science.gov (United States)

    2005-12-09

    Ocean circulation is shown to influence the bio -optical properties in open and coastal waters in the Gulf of Mexico. 3-dimensional physical ocean...supportive evidence of the degree which physical processes influence bio -optical processes in the surface ocean. NCOM assimilates daily SST along with...provide daily real-time observations. We demonstrate the response of the Mississippi River plume (observed through bio -optical signatures), to coastal

  9. Basin Analysis and Petroleum System Characterization and Modeling, Interior Salt Basins, Central and Eastern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini; Paul Aharon; Donald A. Goddard; Roger Barnaby

    2006-05-26

    The principal research effort for Phase 1 (Concept Development) of the project has been data compilation; determination of the tectonic, depositional, burial, and thermal maturation histories of the North Louisiana Salt Basin; basin modeling (geohistory, thermal maturation, hydrocarbon expulsion); petroleum system identification; comparative basin evaluation; and resource assessment. Existing information on the North Louisiana Salt Basin has been evaluated, an electronic database has been developed, and regional cross sections have been prepared. Structure, isopach and formation lithology maps have been constructed, and burial history, thermal maturation history, and hydrocarbon expulsion profiles have been prepared. Seismic data, cross sections, subsurface maps and burial history, thermal maturation history, and hydrocarbon expulsion profiles have been used in evaluating the tectonic, depositional, burial and thermal maturation histories of the basin. Oil and gas reservoirs have been found to be associated with salt-supported anticlinal and domal features (salt pillows, turtle structures and piercement domes); with normal faulting associated with the northern basin margin and listric down-to-the-basin faults (state-line fault complex) and faulted salt features; and with combination structural and stratigraphic features (Sabine and Monroe Uplifts) and monoclinal features with lithologic variations. Petroleum reservoirs include Upper Jurassic and Cretaceous fluvial-deltaic sandstone facies; shoreline, marine bar and shallow shelf sandstone facies; and carbonate shoal, shelf and reef facies. Cretaceous unconformities significantly contribute to the hydrocarbon trapping mechanism capacity in the North Louisiana Salt Basin. The chief petroleum source rock in this basin is Upper Jurassic Smackover lime mudstone beds. The generation of hydrocarbons from Smackover lime mudstone was initiated during the Early Cretaceous and continued into the Tertiary. Hydrocarbon

  10. Residence time of pollutants discharged in the Gulf of Kachchh, northwestern Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Patgaonkar, R.S.; Vethamony, P.; Lokesh, K.S.; Babu, M.T.

    A 2D Hydrodynamic-Particle Analysis model was applied to the Gulf of Kachchh (GoK) to estimate the residence time of pollutants. The tidal currents in the Gulf have a strong E-W component, which prevents the material in the north being transported...

  11. Danish Gulf War Veterans Revisited

    DEFF Research Database (Denmark)

    Nissen, Lars Ravnborg; Stoltenberg, Christian; Nielsen, Anni B Sternhagen

    2016-01-01

    OBJECTIVE: To examine the assumption that postdeployment incidence of sickness and other absence from work are higher among Gulf War Veterans compared with nonveterans. METHODS: A prospective registry study including a cohort of 721 Danish Gulf War Veterans and a control cohort of 3,629 nonveterans...... and nonveterans in the incidence rate of long-term sickness absence. After an initial short period (3 months) with elevated incidence rate of long-term absence from work among veterans, there was no difference between the cohorts. CONCLUSION: Among Danish Gulf War Veterans, no postdeployment increased risk...

  12. Gulf Coast Geology (GCG) Online

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A large percentage of the present and future energy resources of the United States reside in the Gulf of Mexico Basin, one of the major hydrocarbon producing areas...

  13. Oceanographic and fisheries data collected from NOAA and academic research vessels, and commercial menhaden vessels in Gulf of Mexico from 1988-06-14 to 1991-06-22 (NCEI Accession 0156304)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Oceanographic and fisheries data were collected during 1988 through 1991 through a multiagency research project to develop a remote sensing system to provide near...

  14. Mapping the Intricacies of the Gulf of Mexico's Circulation

    Science.gov (United States)

    Lugo-Fernández, Alexis; Green, Rebecca E.

    2011-01-01

    From hosting key shipping lines, drilling platforms, and commercial fisheries, to sustaining mangrove swamps that shelter the coastline from the hurricanes that churn its waters, the Gulf of Mexico is important to the nations surrounding it for socio-economic, ecological, military, political, and scientific reasons. Critical to all of these sectors is the Gulf's circulation—it controls hurricane tracks and intensity, biological productivity, and larvae dispersal. Since 1982, the Environmental Studies Program (ESP) of the U.S. Bureau of Ocean Energy Management, Regulation and Enforcement (BOEMRE) has invested more than $67 million in field and numerical modeling studies to improve our understanding of the Gulf's circulation (see Figure 1). ESP-funded research has covered a broad array of topics, some applied and some basic. Studies carried out on behalf of the bureau reflect the bureau's information needs, stakeholder input, and offshore energy exploration and development trends. All ESP studies culminate in a technical report—127 technical reports on physical oceanography are publicly available (see http://www.gomr.boemre.gov/homepg/regulate/environ/techsumm/rec_pubs.html). Additionally, more than 100 peer-reviewed publications have been issued on the Gulf's physical oceanography and circulation. The AGU Geophysical Monograph Circulation in the Gulf of Mexico: Observations and Models, the very first circulation overview since 1972, was funded by ESP. Additionally, data collected during fieldwork are deposited in national archives for public dissemination.

  15. Chronic Fatigue Syndrome in Gulf War Veterans

    Science.gov (United States)

    ... Enter ZIP code here Enter ZIP code here Chronic Fatigue Syndrome in Gulf War Veterans Gulf War ... and be at least 10 percent disabling. About Chronic Fatigue Syndrome CFS is an unexplained, severe and ...

  16. Gulf of Mexico Deepwater Bathymetry with Hillshade

    Data.gov (United States)

    Bureau of Ocean Energy Management, Department of the Interior — Gulf of Mexico Depth Grid Cells derived from BOEM's seismic grid compilation. BOEM's deepwater Gulf of Mexico bathymetry grid. Created by mosaicing over 100 3D...

  17. Gulf Coast Basins and Uplifts [gcstructsg

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — These data provide generalized outlines of major basins and uplifts in the Gulf Coast region modified after Plate 2, Principal structural features, Gulf of Mexico...

  18. Temperature of the Gulf Stream

    Science.gov (United States)

    2002-01-01

    The Gulf Stream is one of the strong ocean currents that carries warm water from the sunny tropics to higher latitudes. The current stretches from the Gulf of Mexico up the East Coast of the United States, departs from North America south of the Chesapeake Bay, and heads across the Atlantic to the British Isles. The water within the Gulf Stream moves at the stately pace of 4 miles per hour. Even though the current cools as the water travels thousands of miles, it remains strong enough to moderate the Northern European climate. The image above was derived from the infrared measurements of the Moderate-resolution Imaging Spectroradiometer (MODIS) on a nearly cloud-free day over the east coast of the United States. The coldest waters are shown as purple, with blue, green, yellow, and red representing progressively warmer water. Temperatures range from about 7 to 22 degrees Celsius. The core of the Gulf Stream is very apparent as the warmest water, dark red. It departs from the coast at Cape Hatteras, North Carolina. The cool, shelf water from the north entrains the warmer outflows from the Chesapeake and Delaware Bays. The north wall of the Gulf Stream reveals very complex structure associated with frontal instabilities that lead to exchanges between the Gulf Stream and inshore waters. Several clockwise-rotating warm core eddies are evident north of the core of the Gulf Stream, which enhance the exchange of heat and water between the coastal and deep ocean. Cold core eddies, which rotate counter clockwise, are seen south of the Gulf Stream. The one closest to Cape Hatteras is entraining very warm Gulf Stream waters on its northwest circumference. Near the coast, shallower waters have warmed due to solar heating, while the deeper waters offshore are markedly cooler (dark blue). MODIS made this observation on May 8, 2000, at 11:45 a.m. EDT. For more information, see the MODIS-Ocean web page. The sea surface temperature image was created at the University of Miami using

  19. RESULTS FROM THE (1) DATA COLLECTION WORKSHOP, (2) MODELING WORKSHOP AND (3) DRILLING AND CORING METHODS WORKSHOP AS PART OF THE JOINT INDUSTRY PARTICIPATION (JIP) PROJECT TO CHARACTERIZE NATURAL GAS HYDRATES IN THE DEEPWATER GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Stephen A. Holditch; Emrys Jones

    2002-09-01

    In 2000, Chevron began a project to learn how to characterize the natural gas hydrate deposits in the deepwater portions of the Gulf of Mexico. A Joint Industry Participation (JIP) group was formed in 2001, and a project partially funded by the U.S. Department of Energy (DOE) began in October 2001. The primary objective of this project is to develop technology and data to assist in the characterization of naturally occurring gas hydrates in the deepwater Gulf of Mexico. These naturally occurring gas hydrates can cause problems relating to drilling and production of oil and gas, as well as building and operating pipelines. Other objectives of this project are to better understand how natural gas hydrates can affect seafloor stability, to gather data that can be used to study climate change, and to determine how the results of this project can be used to assess if and how gas hydrates act as a trapping mechanism for shallow oil or gas reservoirs. As part of the project, three workshops were held. The first was a data collection workshop, held in Houston during March 14-15, 2002. The purpose of this workshop was to find out what data exist on gas hydrates and to begin making that data available to the JIP. The second and third workshop, on Geoscience and Reservoir Modeling, and Drilling and Coring Methods, respectively, were held simultaneously in Houston during May 9-10, 2002. The Modeling Workshop was conducted to find out what data the various engineers, scientists and geoscientists want the JIP to collect in both the field and the laboratory. The Drilling and Coring workshop was to begin making plans on how we can collect the data required by the project's principal investigators.

  20. Intrinsic low-frequency variability of the Gulf Stream

    NARCIS (Netherlands)

    Quattrocchi, G.; Pierini, S.; Dijkstra, H.A.

    2012-01-01

    In this paper a process study aimed at analyzing the low-frequency variability of intrinsically oceanic origin of the Gulf Stream (GS) and GS extension (GSE) is presented. An eddy-permitting reduced-gravity nonlinear shallow water model is implemented in an idealized North Atlantic Ocean, with schem

  1. Intrinsic low-frequency variability of the Gulf Stream

    NARCIS (Netherlands)

    Quattrocchi, G.; Pierini, S.; Dijkstra, H.A.

    2012-01-01

    In this paper a process study aimed at analyzing the low-frequency variability of intrinsically oceanic origin of the Gulf Stream (GS) and GS extension (GSE) is presented. An eddy-permitting reduced-gravity nonlinear shallow water model is implemented in an idealized North Atlantic Ocean, with

  2. EAARL Coastal Topography and Imagery--Naval Live Oaks Area, Gulf Islands National Seashore, Florida, 2007

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A digital elevation map (also known as a Digital Elevation Model, or DEM) of the Naval Live Oaks Area in Florida's Gulf Islands National Seashore was produced from...

  3. EAARL Coastal Topography and Imagery--Naval Live Oaks Area, Gulf Islands National Seashore, Florida, 2007

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — A digital elevation map (also known as a Digital Elevation Model, or DEM) of the Naval Live Oaks Area in Florida's Gulf Islands National Seashore was produced from...

  4. Deglacial climatic oscillations in the Gulf of California

    Science.gov (United States)

    Keigwin, L. D.; Jones, G. A.

    1990-12-01

    A high-resolution, accelerator radiocarbon dated climate record of the interval 8,000-18,000 years B.P. from Deep Sea Drilling Project site 480 (Guaymas Basin, Gulf of California) shows geochemical and lithological oscillations of oceanographic and climatic significance during deglaciation. Nonlaminated sediments are associated with cooler climatic conditions during the late glacial (up to 13,000 years B.P.), and from 10,300 to 10,800 years B.P., equivalent to the Younger Dryas event of the North Atlantic region. We propose that the changes from laminated (varved) to nonlaminated sediments resulted from increased oxygen content in Pacific intermediate waters during the glacial and the Younger Dryas episodes, and that the forcing for the latter event was global in scope. Prominent events of low δ18O are recorded in benthic foraminifera from 8,000 to 10,000 and at 12,000 years B.P.; evidence for an earlier event between 13,500 and 15,000 years B.P. is weaker. Maximum δ18O is found to have occurred 10,500, 13,500, and 15,000 years ago (and beyond). Oxygen isotopic variability most likely reflects changing temperature and salinity characteristics of Pacific waters of intermediate depth during deglaciation or environmental changes within the Gulf of California region. Several lines of evidence suggest that during deglaciation the climate of the American southwest was marked by increased precipitation that could have lowered salinity in the Gulf of California. Recent modelling studies show that cooling of the Gulf of Mexico due to glacial meltwater injection, which is believed to have occurred at least twice during deglaciation, would have resulted in increased precipitation with respect to evaporation in the American southwest during summertime. The timing of deglacial events in the Gulf of Mexico and the Gulf of California supports such an atmospheric teleconnection.

  5. Anisotropic models to account for large borehole washouts to estimate gas hydrate saturations in the Gulf of Mexico Gas Hydrate Joint Industry Project Leg II Alaminos 21 B well

    Science.gov (United States)

    Lee, M.W.; Collett, T.S.; Lewis, K.A.

    2012-01-01

    Through the use of 3-D seismic amplitude mapping, several gashydrate prospects were identified in the Alaminos Canyon (AC) area of the Gulf of Mexico. Two locations were drilled as part of the Gulf of MexicoGasHydrate Joint Industry Project Leg II (JIP Leg II) in May of 2009 and a comprehensive set of logging-while-drilling (LWD) logs were acquired at each well site. LWD logs indicated that resistivity in the range of ~2 ohm-m and P-wave velocity in the range of ~1.9 km/s were measured in the target sand interval between 515 and 645 feet below sea floor. These values were slightly elevated relative to those measured in the sediment above and below the target sand. However, the initial well log analysis was inconclusive regarding the presence of gashydrate in the logged sand interval, mainly because largewashouts caused by drilling in the target interval degraded confidence in the well log measurements. To assess gashydratesaturations in the sedimentary section drilled in the Alaminos Canyon 21B (AC21-B) well, a method of compensating for the effect of washouts on the resistivity and acoustic velocities was developed. The proposed method models the washed-out portion of the borehole as a vertical layer filled with sea water (drilling fluid) and the apparent anisotropic resistivity and velocities caused by a vertical layer are used to correct the measured log values. By incorporating the conventional marine seismic data into the well log analysis, the average gashydratesaturation in the target sand section in the AC21-Bwell can be constrained to the range of 8–28%, with 20% being our best estimate.

  6. Tomographic evidence for a subducted seamount beneath the Gulf of Nicoya, Costa Rica: The cause of the 1990 Mw = 7.0 Gulf of Nicoya earthquake

    Science.gov (United States)

    Husen, S.; Kissling, E.; Quintero, R.

    2002-04-01

    Tomographic images constrain the existence of a subducted seamount beneath the Gulf of Nicoya, Costa Rica. The subducted seamount is found at a depth of 30 km within the rupture area of the March 25, 1990, Mw = 7.0 Gulf of Nicoya earthquake. The Gulf of Nicoya earthquake was a typical thrust-type subduction earthquake and occurred on a shallow dipping thrust fault parallel or along the boundary between the subducting Cocos plate and the overriding plate. Precise relocation of the mainshock and its aftershocks in a 3-D P-wave velocity model shows that the area of the mainshock rupture is coincident with the imaged subducted seamount. Most of the aftershocks are relocated within or close to the inferred subducted seamount above the subducting oceanic plate. We interpret the subducted seamount as an asperity whose rupture caused the 1990 Gulf of Nicoya earthquake.

  7. Gulf and Dilmun Type seals

    DEFF Research Database (Denmark)

    Laursen, Steffen

    2011-01-01

    these Gulf Type‘ seals drew heavily on Indus Valley iconography and Indus script was occasionally employed in a pidgin-like manner. While the earliest circular seals incorporate features from Mesopotamian glyptic only to a lesser extent, this becomes a more important source of inspiration for later Dilmun...

  8. Gulf War Illness Research Program

    Science.gov (United States)

    2010-01-01

    neurofibromato- sis; autism ; and other areas with military health interests including psychological health, traumatic brain injury, and Gulf War Illness (GWI...the national news headlines, it has not dimmed our hope that treatments and cures for GWI are waiting to be discovered and brought to bear against

  9. Blood Biomarkers of Chronic Inflammation in Gulf War Illness.

    Directory of Open Access Journals (Sweden)

    Gerhard J Johnson

    Full Text Available More than twenty years following the end of the 1990-1991 Gulf War it is estimated that approximately 300,000 veterans of this conflict suffer from an unexplained chronic, multi-system disorder known as Gulf War Illness (GWI. The etiology of GWI may be exposure to chemical toxins, but it remains only partially defined, and its case definition is based only on symptoms. Objective criteria for the diagnosis of GWI are urgently needed for diagnosis and therapeutic research.This study was designed to determine if blood biomarkers could provide objective criteria to assist diagnosis of GWI.A surveillance study of 85 Gulf War Veteran volunteers identified from the Department of Veterans Affairs Minnesota Gulf War registry was performed. All subjects were deployed to the Gulf War. Fifty seven subjects had GWI defined by CDC criteria, and 28 did not have symptomatic criteria for a diagnosis of GWI. Statistical analyses were performed on peripheral blood counts and assays of 61 plasma proteins using the Mann-Whitney rank sum test to compare biomarker distributions and stepwise logistic regression to formulate a diagnostic model.Lymphocyte, monocyte, neutrophil, and platelet counts were higher in GWI subjects. Six serum proteins associated with inflammation were significantly different in GWI subjects. A diagnostic model of three biomarkers-lymphocytes, monocytes, and C reactive protein-had a predicted probability of 90% (CI 76-90% for diagnosing GWI when the probability of having GWI was above 70%.The results of the current study indicate that inflammation is a component of the pathobiology of GWI. Analysis of the data resulted in a model utilizing three readily measurable biomarkers that appears to significantly augment the symptom-based case definition of GWI. These new observations are highly relevant to the diagnosis of GWI, and to therapeutic trials.

  10. Modified Gulf of California model for South Georgia,north Scotia Ridge, and implications for the Rocas Verdes back-arc basin, southern Andes

    Science.gov (United States)

    Alabaster, T.; Storey, B. C.

    1990-06-01

    New field mapping and an integrated trace element and Nd isotopic study have been undertaken on the Jurassic-Cretaceous Larsen Harbour Complex on the island of South Georgia, recognized as a displaced part of the southern Andes ensialic, autochthonous Rocas Verdes marginal basin. Five basalt groups (Groups I-V) are identified from trace element data; initial Nd isotopic compositions suggest that they are derived from only two sources. Magmas produced during early stages of continental lithospheric attenuation (Groups I-III) were derived by varying degrees of partial melting and fractional crystallization from a large ion lithophile element (LILE)-enriched, low-ɛNd mantle source relative to normal (N)-type mid-ocean ridge basalt (MORB). Magmas produced during later stages of rifting (Groups IV and V) were, however, derived from a high-ɛNd asthenospheric mantle source similar to N-type MORB, unaffected by earlier LILE enrichment. Our data do not concur with previous suggestions that the Larsen Harbour Complex and, by implication, the Rocas Verdes formed in a supra-subduction-zone setting. On the basis of geologic and geochemical evidence, we favor basin formation along an oblique-slip margin akin to that of the Gulf of California.

  11. Collagen Extracted from Persian Gulf Squid Exhibits Anti-Cytotoxic Properties on Apple Pectic Treated Cells: Assessment in an In Vitro Bioassay Model

    Directory of Open Access Journals (Sweden)

    Ladan DELPHI

    2016-10-01

    Full Text Available Background: Collagen-based three-dimensional (3D in vitro systems have been introduced to study the physiological states of cells. As a biomolecule, collagen is usually extracted from terrestrial animals whilst aquatic animals like squid contain large amounts of collagen.Methods: In order to make effective use of marine organisms, we selected Persian Gulf squid in 2015 to extract the required collagen. Then, a 3D culture system based on the extracted collagen was applied to investigate cellular mechanisms in a native microenvironment. The formed collagen gel was used to investigate the growth of MDA-MB-231 breast cancer cells as well as responses to pectic acid.Results: The results revealed that the extracted collagen contained α, ß and γ components with high water holding capacity. This collagen formed a gel-like structure, which could promote the proliferation of MDA-MB-231 breast cancer cells. The MDA-MB-231 cells’ viability in presence of pectic acid, demonstrating the cells’ behavior in a 3D culture system. Conclusion: It seems that the collagen extracted from squid skin has type I collagen properties. It might be used as a substrate in 3D cell culture systems. Keywords: Cell culture, Collagen, Pectic acid, Squid, 3D culture system 

  12. Gulf of Mexico Data Atlas: Digital Data Discovery and Access

    Science.gov (United States)

    Rose, K.

    2014-12-01

    The Gulf of Mexico Data Atlas is an online data discovery and access tool that allows users to browse a growing collection of ecosystem-related datasets visualized as map plates. Thematically, the Atlas includes updated long-term assessments of the physical, biological, environmental, economic and living marine resource characteristics that indicate baseline conditions of the Gulf of Mexico ecosystems. These data are crucial components of integrated ecosystem assessments and modeling and support restoration and monitoring efforts in the Gulf. A multi-agency executive steering committee including members from international, federal, state, and non-governmental organizations was established to guide Atlas development and to contribute data and expertise. The Atlas currently contains over 235 maps in 70 subject areas. Each map plate is accompanied by a descriptive summary authored by a subject matter expert and each data set is fully documented by metadata in Federal Geographic Data Committee (FGDC)-compliant standards. Source data are available in native formats and as web mapping services (WMS). Datasets are also searchable through an accompanying Map Catalog and RSS feed. The Gulf of Mexico Data Atlas is an operational example of the philosophy of leveraging resources among agencies and activities involved in geospatial data as outlined in the US Department of Interior and FGDC "Geospatial Platform Modernization Roadmap v4 - March 2011". We continue to update and add datasets through existing and new partnerships to ensure that the Atlas becomes a truly ecosystem-wide resource.

  13. Deformation in the Central Gulf of California from Geodetic data (Invited)

    Science.gov (United States)

    Plattner, C.; Malservisi, R.; Amelung, F.

    2009-12-01

    The spatial and temporal variation of lithospheric strain provides important information for understanding the rifting process at continental margins. However, in the Gulf of California rift system even the modern strain distribution is poorly known. Our geodetic study aims on filling this gap of knowledge by quantifying the plate boundary deformation in the Gulf of California considering different timescales. In the past, Plattner et al. (2007) determined the Baja California - North America rigid plate relative motion, which is comparable with 3Myr-average seafloor spreading rates in the Gulf of California. Here, we study interseismic deformation in the central Gulf of California and coseismic strain release during the August 2009 earthquakes. Our analysis is based on InSAR data acquired by Envisat over a broad area across Baja California, islands in the central Gulf of California, and Sonora. Data from 1993 to May 2009 are used for studying interseismic strain accumulation, considering both, a time-independent model, and a time-dependent model. InSAR data from 2009 only is used in modeling the coseismic displacement during the August 3rd 2009 M 6.9 earthquake. Our modeling results provide information on the modern strain accumulation pattern and fault slip in the Gulf of California. Furthermore, we characterize the parameters of strain accumulation, in particular the Ballenas transform fault.

  14. Water Level and Current Simulation for LOTS Operations - Persian Gulf and Gulf of Oman

    Science.gov (United States)

    1994-07-01

    equations are solved by a finite element approach. However the equations are reformulated mathematically to a form with much improved numerical solution...longer than the tidal cycle, since tidal ebb and flood currents tend to cancel each other. 23Chqpwr 3 Ceibraga wnd Vedication 30 25 (Z 20 M2 "W 15 0 10Q...circulation in the Arabian Gulf," Applied Mathematical Modeling, 14, 410-419. Bogdanov, K. T. (1987). "T’idal wave propagation and tidal level oscillations

  15. The determinants of Islamic banks’ liquidity in Malaysia and the Gulf Corporation Council

    OpenAIRE

    Tunku Mahmood Fawzy, Tunku Suleiman

    2016-01-01

    Purpose – The study explores the determinants of Islamic banks’ liquidity in Malaysia and the Gulf Corporation Council countries. Design/methodology/approach – The study takes the context of Islamic banks in Malaysia and the Gulf Corporation Council between 2009 and 2014 except the Sultanate of Oman. The Sultanate of Oman was excluded from the sample size because its first Islamic bank only began operations in 2012. The study used a fixed effect least square model. The two dependent variab...

  16. A conceptual model for hydrocarbon accumulation and seepage processes inside Chapopote asphalt volcanism site, Southern Gulf of Mexico: from high resolution seismic point of view

    Science.gov (United States)

    Ding, F.; Spiess, V.; Fekete, N.; Keil, H.; Bohrmann, G.

    2007-05-01

    As part of the German R/V Meteor M67/2 expedition in 2006 to the southern Gulf of Mexico, a set of 2D high resolution seismic profiles was acquired across the Chapopote knoll to study sea floor asphalt occurrences and their origin. Based on regional seismic stratigraphy studies, correlated to DSDP sites, a higher reflective coarse grained sediment unit of Late Miocene age is identified as a potential shallow gas reservoir, overlain by a low permeability fine grained Pliocene and Pleistocene cover. As a result of salt diapirism, local uplift has caused reduced accumulation rates above the diaper since the late Pliocene, while the rates had been uniform throughout the area before. This has further improved the seal properties, since more fine grained material deposited in elevated locations. Nevertheless, on the crest of Chapopote, sediments above the coarse sediment unit are only around 150-75 m thick. Since oil and gas production can well be expected at depth in Jurassic and Tertiary source rocks, the presence of high amplitude reflector packages within the reservoir unit is interpreted as a result of the presence of hydrocarbons. This interpretation is further supported by the observation that some reflectors are cross-cutting and/or reveal a drop in instantaneous frequency. But, the thin seal above the reservoir unit, located directly underneath a widespread occurrence of asphalts at the sea floor, probably facilitates the leakage of hydrocarbons trapped inside the reservoir through a ~ 750 m wide acoustically chaotic zone partly aided by faulting. Since the top of Chapopote shows a high structural complexity, more seepage sites may exist beyond where seafloor asphalts have been found so far. Evolution and structure of the migration and reservoir system, which may be deep rooted, will be discussed both with respect to shallow gas and asphalt occurrences.

  17. The Persian Gulf Region. A Climatological Study

    Science.gov (United States)

    1990-05-01

    classic Miller TYPICAL WEATHER. The following weather conditions AWSTR-200 wet bulb zero heights above terrain are typical of the Persian Gulf proper...Oman; it dominates during expected. Hail should be assumed when the the early part of the transition season. It is classic Miller AWSTR-200 wet bulb ...southern gulf shore. rapidly to 70NM just east of Dubai . Gulf waters are relatively shallow--average depth varies THE STRAIT OF HORMUZ. At Dubai , the

  18. Seismotectonics and Neotectonics of the Gulfs of Gökova-Kuşadasi-Siǧacik and Surrounding Regions (SW Turkey): Earthquake Mechanisms, Source Rupture Modeling, Tsunami Hazard and Geodynamic Implications

    Science.gov (United States)

    Yolsal-Cevikbilen, Seda; Karaoglu, Özgür; Taymaz, Tuncay; Helvaci, Cahit

    2013-04-01

    The mechanical behavior of the continental lithosphere for the Aegean region is one of the foremost interesting geological disputes in earth sciences. The Aegean region provides complex tectonic events which produced a strong heterogeneity in the crust (i.e. large thrusts and exhumation shear zones or extensional detachments) as such in among most continental regions. In order to investigate mechanical reasons of the ongoing lithospheric-scale extension within the region, we must tackle all of the existing kinematic and dynamic agents: (1) roll back of the subduction slab and back arc extension; (2) westward extrusion of the Anatolian micro-plate; (3) block rotations of the Aegean region and western Anatolia; and (4) transtensional transform faults. Furthermore, seismological studies, particularly earthquake source mechanisms and rupture modeling, play important roles on deciphering the ongoing deformation and seismotectonic characteristics of the region. Recently, many moderate earthquakes occurred in the Gulfs of Gökova, Kuşadası, Sıǧacık and surroundings. In the present study, we examined source mechanisms and rupture histories of those earthquakes with Mw > 5.0 in order to retrieve the geometry of active faulting, source characteristics, kinematic and dynamic source parameters and current deformations of the region by using teleseismic body-waveform inversion of long-period P- and SH-waves, and broad-band P-waveforms recorded by GDSN and FDSN stations. We also checked first motion polarities of P- waveforms recorded at regional and teleseismic stations and applied several uncertainty tests to find the error limits of minimum misfit solutions. Inversion results revealed E-W directed normal faulting mechanisms with small amount of left lateral strike slip components in the Gulf of Gökova and NE-SW oriented right lateral strike slip faulting mechanisms in the Gulf of Sıǧacık. Earthquakes mostly have N-S and NW-SE directed T- axes directions which are

  19. Physical Oceanography of the Gulf of Aden

    Digital Repository Service at National Institute of Oceanography (India)

    Al Saafani, M.A.

    maps of Seriy and Khimitsa [1963] indicated two eddies in the Gulf of Aden during the winter monsoon, one cyclonic in the gulf, east of 50 ◦ E, and the other anticyclonic to the east of the gulf off Ras Fartak. Mohammed and Kolli [1992] used... the hydrographic data from three cruises to de- scribe the circulation in the northern Gulf of Aden. During January, one cyclonic eddy developed between 46 ◦ E and 50 ◦ E. West of the cyclonic eddy, the flow was towards Bab el Mandab. During May, the flow...

  20. The outer Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Henery, D. [Shell Internationale Petroleum Maatschappij BV, Den Haag (Netherlands)

    1996-12-31

    This paper deals with the offshore activity in the Gulf of Mexico. Up to the end of 1995 there have been close to 300 exploratory wells drilled in water depths beyond 450 metres, and over 50 development wells. In addition approximately 1.500 leases have been awarded in the deep water. Themes discussed are deep water discoveries, average well rates, and key learnings points

  1. The Loop Current Dynamics Experiment (2009-2011) in the Gulf of Mexico

    Science.gov (United States)

    Lugo-Fernández, Alexis

    2016-12-01

    The Environmental Studies Program of the US Department of the Interior's Bureau of Ocean Energy Management (BOEM) has sponsored oceanographic research in the Gulf of Mexico for over 40 years. Since 1998, BOEM and its predecessor agencies funded several oceanographic studies on the Gulf's continental slope and beyond. These investigations were aimed at discovering and understanding the physical process driving the circulation and improving numerical models' forecasting skills. One common finding in many of those studies was the ubiquitous influence that the Loop Current (LC) and its associated eddies have on the Gulf's circulation. The LC dominance of the upper layer circulation has been well established by previous studies. Many of these studies suggested that the LC is a source of deep energy below the main thermocline. Yet, despite its acknowledged importance to the Gulf circulation, there had been few observational studies of the LC itself particularly in the main eddy shedding regime.

  2. Review of the circulation in the Beibu Gulf, South China Sea

    Science.gov (United States)

    Gao, Jingsong; Wu, Guidan; Ya, Hanzheng

    2017-04-01

    Although Beibu Gulf holds a significant geographical location and is rich in fishery resources, it has attracted only limited attention from researchers in recent decades. This study summarizes the conclusions based on the observations and model results regarding the circulation and cold water mass in the Beibu Gulf to provide a reference for further research. Affected by wind and density gradient, the spring circulation may be gulf-scale cyclonic and nested with an enclosed cyclonic gyre in the northern gulf and unclosed cyclonic gyre in the southern gulf. Meanwhile, the mechanisms of summer circulation remain controversial. Along with the results of a new numerical model, historical observations suggest that summer circulation is cyclonic and anticyclonic in the northern and southern gulfs, respectively. The northern and southern gulfs are mainly influenced by wind stress curl and South China Sea current, respectively. Similarly, although different views regarding the structure of winter circulation have been presented, a large amount of evidence supports the existence of two cyclonic gyres in the northern and southern gulfs. In addition, a southwestward current off the northwestern coast of Hainan Island is present. The circulation structure in the fall is similar to that in winter. However, the cyclonic gyre in the southern Gulf has a greater tendency to intrude northwards into the Beibu Gulf in fall than in winter, and the currents off the coast of Vietnam and the northwestern coast of Hainan Island are weaker in fall than those in winter. Most studies indicate that winter boreal circulation is driven by the monsoon wind. The most recent observations and model results suggest that the current in the Qiongzhou Strait (QS) is eastward on certain days in the boreal summer and is affected by the difference between the sea levels of the two ends of the QS and tidal rectification. Correspondingly, the volume transport is approximately -0.1 Sv (minus sign represents

  3. Citizenship and migration in Arab Gulf monarchies

    DEFF Research Database (Denmark)

    Sater, J.

    2014-01-01

    In many industrialized countries, the issue of migration has traditionally raised the question of whether migrant groups fully enjoy citizenship rights. Political debates about models of migration emphasize either the values of cultural diversity or the value of integration into 'host' societies...... to migrants, but also with regard to local populations. In addition to the contested nature of citizenship, migrants' lack of citizenship rights fulfils distinctive functions in what Saskia Sassen calls 'global cities'. This concept links the Arab world with a new phenomenon of globalized migration in which...... the lack of both integration and citizenship is a defining principle. Using these two perspectives, this article examines the relationship between citizenship rights and migration in the Gulf region, drawing on data from the UAE along with Bahrain, Kuwait, and Qatar....

  4. Responses of the circulation and water mass in the Beibu Gulf to the seasonal forcing regimes

    Institute of Scientific and Technical Information of China (English)

    GAO Jingsong; SHI Maochong; CHEN Bo; GUO Peifang; ZHAO Dongliang

    2014-01-01

    In the past 20 a, the gulf-scale circulation in the Beibu Gulf has been commonly accepted to be driven by a wind stress or density gradient. However, using three sensitive experiments based on a three-dimensional baroclinic model that was verified by observations, the formation mechanisms were revealed:the circula-tion in the northern Beibu Gulf was triggered by the monsoon wind throughout a year;whereas the southern gulf circulation was driven by the monsoon wind and South China Sea (SCS) circulation in winter and sum-mer, respectively. The force of heat flux and tidal harmonics had a strong effect on the circulation strength and range, as well as the local circulation structures, but these factors did not influence the major circulation structure in the Beibu Gulf. On the other hand, the Beibu Gulf Cold Water Mass (BGCWM) would disappear without the force of heat flux because the seasonal thermocline layer was generated by the input of heat so that the vertical mixing between the upper hot water and lower cold water was blocked. In addition, the wind-induced cyclonic gyre in the northern gulf was favorable to the existence of the BGCWM. However, the coverage area of the BGCWM was increased slightly without the force of the tidal harmonics. When the model was driven by the monthly averaged surface forcing, the circulation structure was changed to some extent, and the coverage area of the BGCWM almost extended outwards 100%, implying the circulation and water mass in the Beibu Gulf had strong responses to the temporal resolution of the surface forces.

  5. The Proto Southern Gulf of California represented by GIS Plate Tectonic Reconstructions

    Science.gov (United States)

    Skinner, L. A.; Umhoefer, P. J.; Kluesner, J. W.

    2012-12-01

    We present GIS-based plate tectonic reconstruction maps for the southern Gulf of California oblique rift. The maps track plate boundary deformation back to 14 Ma. Tectonic blocks are defined by faults, geology, seismic data, and bathymetry/topography. Spreading center and fault-slip rates were acquired from geologic data, cross-Gulf tie points, and GPS studies. Baja California-North America GPS rates (47 mm/yr across the Gulf; 4 mm/yr in the borderland) agree remarkably with ~6 Ma geologic offsets across the Gulf and are used during reconstruction steps back to 6 Ma. The Alarcon and Guaymas spreading centers initiated at 2.4 Ma and 6 Ma (Lizarralde et al., 2007), respectively, while the Farallon, Pescadero, and Carmen spreading centers began between ~2-1 Ma (Lonsdale, 1989). Therefore, the 2, 4, and 6 Ma reconstruction steps include a long transtensional fault zone along much of the southern Gulf, connecting the Guaymas spreading center with either the Alarcon spreading center or East Pacific Rise. For reconstructions at 8, 10, and 12 Ma, a range of across-Gulf and borderland fault rates fit the current constraints, but all models suggest an increase in across-Gulf faulting rates at 8 - 6 Ma. We used 30 mm/yr across the Gulf and 20 mm/yr across the borderland. These models result in ~470 km northwestward offset across the Gulf (we also account for a minor E-W offset) and ~145 km offset across the borderland. The 12 - 14 Ma reconstructions suggest that the Gulf of California formed along a 100 x 1600 km volcanic arc and narrow extensional belt between the Cretaceous batholith and the Sierra Madre Occidental. The initial seaway at 8 - 6.5 Ma was only ~200-250 km wide by 1600 km long. We will also combine our 12 Ma map with the McQuarrie and Werrnicke (2005) reconstruction to present a new reconstruction for the whole Walker Lane to Gulf of California belt.

  6. Probiotic (VSL#3) for Gulf War Illness

    Science.gov (United States)

    2011-10-01

    Changes in Fecal Microbiota of Gulf War Veterans with Irritable Bowel Syndrome. I was invited to write an editorial in the journal of Digestive...8 Appendices Abstract (Presented at the Digestive Disease Week Changes in Fecal Microbiota of Gulf...diarrhea-predominant IBS had fewer detectable bacterial groups (average of 270 subfamilies) than mixed IBS (average of 360 subfamilies) and healthy

  7. Israel : Gulf of Aqaba Environmental Action Plan

    OpenAIRE

    World Bank; European Union

    2000-01-01

    The Gulf of Aqaba Environmental Action Plan (GAEAP) represents for the Government of Israel a step towards achieving the national environmental objectives outlined in its legislation. The proposed actions, both curative and preventive, will protect the Gulf's land and water interface and ensure conservation of natural resources within a framework in which economic development can take plac...

  8. Fishery potential of the Gulf of Kachchh

    Digital Repository Service at National Institute of Oceanography (India)

    Nair, V.R.; Govindan, K.; Ramaiah, Neelam; Gajbhiye, S.N.

    Fishery potential of the interior Gulf of Kachchh and adjacent creek regions was reported for the first time as baseline data for future ecological assessment. The experimental trawling and gill netting indicated that the inner Gulf (av. 7.8 kg...

  9. Sandwaves of the Gulf of Khambhat

    Digital Repository Service at National Institute of Oceanography (India)

    Vora, K.H.; Gujar, A.R.; Karisiddaiah, S.M.

    In the Gulf of Khambhat (Gujarat, India) the best formed sandwaves are seen in the west close to the Eastern Sand Bank. With increasing clay content and clay cover of the sea bed, the sandwaves become poorly formed. In the southern part of the Gulf...

  10. CEOs: Gulf crisis hits hospitals' bottom line.

    Science.gov (United States)

    Johnsson, J

    1990-12-01

    Hospital CEOs say the Persian Gulf crisis could hit them hard where it counts. In fact, hospitals are already seeing some adverse impact from events in the Middle East. From fundraising to plant management to strategic planning, the confrontations in the Gulf are having an impact on the hospital's bottom line.

  11. OCEANOGRAPHY IN THE GULF OF MEXICO.

    Science.gov (United States)

    The report gives a summary of oceanographic research in the Gulf of Mexico supported by the Office of Naval Research during the period 1 May 1961...15 December 1969. This research involved theoretical studies in ocean dynamics; currents in the Gulf of Mexico , Cayman Sea, western tropical Atlantic

  12. Artificial neural network modeling and cluster analysis for organic facies and burial history estimation using well log data: A case study of the South Pars Gas Field, Persian Gulf, Iran

    Science.gov (United States)

    Alizadeh, Bahram; Najjari, Saeid; Kadkhodaie-Ilkhchi, Ali

    2012-08-01

    Intelligent and statistical techniques were used to extract the hidden organic facies from well log responses in the Giant South Pars Gas Field, Persian Gulf, Iran. Kazhdomi Formation of Mid-Cretaceous and Kangan-Dalan Formations of Permo-Triassic Data were used for this purpose. Initially GR, SGR, CGR, THOR, POTA, NPHI and DT logs were applied to model the relationship between wireline logs and Total Organic Carbon (TOC) content using Artificial Neural Networks (ANN). The correlation coefficient (R2) between the measured and ANN predicted TOC equals to 89%. The performance of the model is measured by the Mean Squared Error function, which does not exceed 0.0073. Using Cluster Analysis technique and creating a binary hierarchical cluster tree the constructed TOC column of each formation was clustered into 5 organic facies according to their geochemical similarity. Later a second model with the accuracy of 84% was created by ANN to determine the specified clusters (facies) directly from well logs for quick cluster recognition in other wells of the studied field. Each created facies was correlated to its appropriate burial history curve. Hence each and every facies of a formation could be scrutinized separately and directly from its well logs, demonstrating the time and depth of oil or gas generation. Therefore potential production zone of Kazhdomi probable source rock and Kangan- Dalan reservoir formation could be identified while well logging operations (especially in LWD cases) were in progress. This could reduce uncertainty and save plenty of time and cost for oil industries and aid in the successful implementation of exploration and exploitation plans.

  13. Application of a hydrodynamic and sediment transport model for guidance of response efforts related to the Deepwater Horizon oil spill in the Northern Gulf of Mexico along the coast of Alabama and Florida

    Science.gov (United States)

    Plant, Nathaniel G.; Long, Joseph W.; Dalyander, P. Soupy; Thompson, David M.; Raabe, Ellen A.

    2013-01-01

    U.S. Geological Survey (USGS) scientists have provided a model-based assessment of transport and deposition of residual Deepwater Horizon oil along the shoreline within the northern Gulf of Mexico in the form of mixtures of sand and weathered oil, known as surface residual balls (SRBs). The results of this USGS research, in combination with results from other components of the overall study, will inform operational decisionmaking. The results will provide guidance for response activities and data collection needs during future oil spills. In May 2012 the U.S. Coast Guard, acting as the Deepwater Horizon Federal on-scene coordinator, chartered an operational science advisory team to provide a science-based review of data collected and to conduct additional directed studies and sampling. The goal was to characterize typical shoreline profiles and morphology in the northern Gulf of Mexico to identify likely sources of residual oil and to evaluate mechanisms whereby reoiling phenomena may be occurring (for example, burial and exhumation and alongshore transport). A steering committee cochaired by British Petroleum Corporation (BP) and the National Oceanic and Atmospheric Administration (NOAA) is overseeing the project and includes State on-scene coordinators from four States (Alabama, Florida, Louisiana, and Mississippi), trustees of the U.S. Department of the Interior (DOI), and representatives from the U.S. Coast Guard. This report presents the results of hydrodynamic and sediment transport models and developed techniques for analyzing potential SRB movement and burial and exhumation along the coastline of Alabama and Florida. Results from these modeling efforts are being used to explain the complexity of reoiling in the nearshore environment and to broaden consideration of the different scenarios and difficulties that are being faced in identifying and removing residual oil. For instance, modeling results suggest that larger SRBs are not, under the most commonly

  14. The Gulf of Mexico ecosystem, six years after the Macondo oil well blowout

    Science.gov (United States)

    Joye, Samantha B.; Bracco, Annalisa; Özgökmen, Tamay M.; Chanton, Jeffrey P.; Grosell, Martin; MacDonald, Ian R.; Cordes, Erik E.; Montoya, Joseph P.; Passow, Uta

    2016-07-01

    The Gulf of Mexico ecosystem is a hotspot for biological diversity and supports a number of industries, from tourism to fishery production to oil and gas exploration, that serve as the economic backbone of Gulf coast states. The Gulf is a natural hydrocarbon basin, rich with stores of oil and gas that lie in reservoirs deep beneath the seafloor. The natural seepage of hydrocarbons across the Gulf system is extensive and, thus, the system's biological components experience ephemeral, if not, frequent, hydrocarbon exposure. In contrast to natural seepage, which is diffuse and variable over space and time, the 2010 Macondo oil well blowout, represented an intense, focused hydrocarbon infusion to the Gulf's deepwaters. The Macondo blowout drove rapid shifts in microbial populations and activity, revealed unexpected phenomena, such as deepwater hydrocarbon plumes and marine ;oil snow; sedimentation, and impacted the Gulf's pelagic and benthic ecosystems. Understanding the distribution and fate of Macondo oil was limited to some degree by an insufficient ability to predict the physical movement of water in the Gulf. In other words, the available physical oceanographic models lacked critical components. In the past six years, much has been learned about the physical oceanography of the Gulf, providing transformative knowledge that will improve the ability to predict the movement of water and the hydrocarbons they carry in future blowout scenarios. Similarly, much has been learned about the processing and fate of Macondo hydrocarbons. Here, we provide an overview of the distribution, fate and impacts of Macondo hydrocarbons and offer suggestions for future research to push the field of oil spill response research forward.

  15. Wave-current interaction near the Gulf Stream during the surface wave dynamics experiment

    Science.gov (United States)

    Wang, David W.; Liu, Antony K.; Peng, Chih Y.; Meindl, Eric A.

    1994-01-01

    This paper presents a case study on the wave-current interaction near the local curvature of a Gulf Stream meander. The wave data were obtained from in situ measurements by a pitch-roll discus buoy during the Surface Wave Dynamics Experiment (SWADE) conducted off Wallops Island, Virginia, from October 1990 to March 1991. Owing to the advection of the Gulf Stream by the semidiurnal tide, the discus buoy was alternately located outside and inside the Gulf Stream. The directional wave measurements from the buoy show the changes in wave direction, wave energy, and directional spreading when waves encountered the current in the Gulf Stream meanders. A wave refraction model, using the ray-tracing method with an estimated Gulf Stream velocity field and meandering condition, was used to simulate wave refraction patterns and to estimate wave parameters at relative locations corresponding to buoy measurements. The numerical simulation shows that a focusing zone of wave rays was formed near the boundary and behind the crest of a simulated Gulf Stream meander. The focusing of wave rays causes changes in wave direction, increases in wave energy, and decreases in wave directional spreading, which are in good agreement with the results from the buoy measurements.

  16. Use of a Florida Gulf Coast Barrier Island by Spring Trans-Gulf Migrants and the Projected Effects of Sea Level Rise on Habitat Availability.

    Directory of Open Access Journals (Sweden)

    Lori A Lester

    Full Text Available Barrier islands on the north coast of the Gulf of Mexico are an internationally important coastal resource. Each spring hundreds of thousands of Nearctic-Neotropical songbirds crossing the Gulf of Mexico during spring migration use these islands because they provide the first landfall for individuals following a trans-Gulf migratory route. The effects of climate change, particularly sea level rise, may negatively impact habitat availability for migrants on barrier islands. Our objectives were (1 to confirm the use of St. George Island, Florida by trans-Gulf migrants and (2 to determine whether forested stopover habitat will be available for migrants on St. George Island following sea level rise. We used avian transect data, geographic information systems, remote sensing, and simulation modelling to investigate the potential effects of three different sea level rise scenarios (0.28 m, 0.82 m, and 2 m on habitat availability for trans-Gulf migrants. We found considerable use of the island by spring trans-Gulf migrants. Migrants were most abundant in areas with low elevation, high canopy height, and high coverage of forests and scrub/shrub. A substantial percentage of forest (44% will be lost by 2100 assuming moderate sea level rise (0.82 m. Thus, as sea level rise progresses, less forests will be available for migrants during stopover. Many migratory bird species' populations are declining, and degradation of barrier island stopover habitat may further increase the cost of migration for many individuals. To preserve this coastal resource, conservation and wise management of migratory stopover areas, especially near ecological barriers like the Gulf of Mexico, will be essential as sea levels rise.

  17. Hydroacoustic estimation of fish biomass in the Gulf of Nicoya, Costa Rica.

    Science.gov (United States)

    Hedgepeth, J; Gallucci, V F; Campos, J; Mug, M

    2000-01-01

    A stratified sampling design was used for a hydroacoustic survey of the inner parts of the Gulf of Nicoya in 1987 and 1988. The bottom topography of the inner Gulf was modeled by introducing the concept of a topographical basin model, as the basis for the projection of the sample survey estimates to the entire inner gulf. The bottom depth contours and volumes for the basin model were constructed from nautical charts. The estimates of sample abundance were made for the fish in the inner Gulf using the acoustic methods, EMS (Expectation Maximization and Smoothing) and echo integration. The estimates of population were made by the multiplication of the topographic model's estimate of water volume and a model of fish density dependent on bottom depth. The results showed a general decrease in fish density biomass with bottom depth, and a simultaneous tendency for maximum concentrations over bottom depths of about four meters. The four meter bottom depth includes a broad expanse of the inner Gulf located south of Isla Chira. Overall estimates of volumetric density (0.269 fish/m3) and of areal densities (1.88 fish/m2) are comparable to other estuarine shallow water environments.

  18. 2007 USGS/NPS/NASA Experimental Advanced Airborne Research Lidar (EAARL): Northern Gulf of Mexico Barrier Islands

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A bare earth elevation map (also known as a Digital Elevation Model, or DEM) of the northern Gulf of Mexico barrier islands and Naval Live Oaks was produced from...

  19. Mercury in Groupers and Sea Basses from the Gulf of Mexico: Relationships with Size, Age, and Feeding Ecology

    National Research Council Canada - National Science Library

    Tremain, Derek M; Adams, Douglas H

    2012-01-01

    We analyzed total mercury concentration in muscle tissue of 15 serranid species (n = 1,401 fish) collected from the Gulf of Mexico and also developed a comprehensive model relating two commonly used mercury analysis methods...

  20. 2007 USGS/NPS/NASA Experimental Advanced Airborne Research Lidar (EAARL): Northern Gulf of Mexico Barrier Islands

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A bare earth elevation map (also known as a Digital Elevation Model, or DEM) of the northern Gulf of Mexico barrier islands and Naval Live Oaks was produced from...

  1. Comment on "Simulation of Surface Ozone Pollution in the Central Gulf Coast Region Using WRF/Chem Model: Sensitivity to PBL and Land Surface Physics"

    Science.gov (United States)

    A recently published meteorology and air quality modeling study has several serious deficiencies deserving comment. The study uses the weather research and forecasting/chemistry (WRF/Chem) model to compare and evaluate boundary layer and land surface modeling options. The most se...

  2. Macro-ecology of Gulf of Mexico cold seeps.

    Science.gov (United States)

    Cordes, Erik E; Bergquist, Derk C; Fisher, Charles R

    2009-01-01

    Shortly after the discovery of chemosynthetic ecosystems at deep-sea hydrothermal vents, similar ecosystems were found at cold seeps in the Gulf of Mexico. Over the past two decades, these sites have become model systems for understanding the physiology of the symbiont-containing megafauna and the ecology of seep communities worldwide. Symbiont-containing bi-valves and siboglinid polychaetes dominate the communities, including five bathymodiolin mussel species and six vestimentiferan (siboglinid polychaete) species in the Gulf of Mexico. The mussels include the first described examples of methanotrophic symbiosis and dual methanotrophic/thiotrophic symbiosis. Studies with the vestimentiferans have demonstrated their potential for extreme longevity and their ability to use posterior structures for subsurface exchange of dissolved metabolites. Ecological investigations have demonstrated that the vestimentiferans function as ecosystem engineers and identified a community succession sequence from a specialized high-biomass endemic community to a low-biomass community of background fauna over the life of a hydrocarbon seep site.

  3. 78 FR 28146 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Shrimp Fishery of the Gulf of...

    Science.gov (United States)

    2013-05-14

    ... Texas estuaries to the Gulf of Mexico (Gulf) so the shrimp may reach a larger, more valuable size and to..., Gulf of Mexico, and South Atlantic; Shrimp Fishery of the Gulf of Mexico; Texas Closure AGENCY... size. DATES: Effective 30 minutes after sunset, May 23, 2013, to 30 minutes after sunset, July 15, 2013...

  4. Effects of the Gulf Stream on ocean waves

    Science.gov (United States)

    Holthuijsen, L. H.; Tolman, H. L.

    1991-01-01

    In the present study a third-generation numerical wave model is used to study effects of a straight Gulf Stream ring on ocean waves in swell and storm conditions. The model accounts for all relevant processes of propagation, generation, and dissipation of the waves (including current effects) without imposing a priori restraints on the spectral development of the waves. The dominating mechanism affecting the waves appears to be current-induced refraction even though the short-crestedness of the incoming waves tends to mask its effects (also in swell conditions). Depending on wind and wave conditions, refraction may trap locally generated waves in the straight Gulf Stream or it may reflect wave energy back to the open ocean. In the Gulf Stream ring, refraction induces a considerable variation in significant wave height and short-crestedness, but it hardly affects the mean wave direction. In storm conditions the processes of generation and dissipation are considerably enhanced in countercurrent situations and reduced following-current situations.

  5. Crustal Deformation in the Southwestern Gulf of Mexico: Underthrusting of the Gulf of Mexico beneath Tehuantepec

    Science.gov (United States)

    Suarez, Gerardo; Aguilar, Sergio

    2016-04-01

    An array of 45 broad band sensors were installed along the Isthmus of Tehuantepec in southeastern. This experiment, called VEOX, was implemented on August 2007 to March 2009. Data were registered continuously during the whole period. In order to search in the seismic records of the data obtained for crustal events in the Isthmus of Tehuantepec, To this purpose, an STA/LTA algorithm was designed to detect earthquakes with S-P times indicating they occurred close the seismic stations, at crustal or upper mantle depths. During the 18 months that the experiment lasted, about 40 crustal earthquakes were recorded in more than three stations, allowing us to determine a hypo central location. All earthquakes occurring at depths greater than 120 km, within the subjected slab, were discarded. The majority of this crustal or upper mantle activity occurred in the northern part of the Isthmus, along the coast of the Gulf of Mexico or just inland from it. No velocity model exists in the area. Therefore, we tested three different velocity models, including one obtained in an adjacent region and based on seismic refraction data. One of these three models rendered the more stable solutions and smaller errors in the hypocentral locations and was used as the local seismic velocity model. In order to improve the quality of the locations, we experimented using a double difference hypocentral algorithm (HYPODD). There was no noticeable improvement in the quality of the hypocenters using this technique. The best located events suggest a southwestern-dipping zone of seismic seismicity, deepening from the Gulf of Mexico towards the interior of the Isthmus of Tehuantepec. The focal mechanisms of the earthquakes indicate the maximum axis of compresion (P axis) is oriented nearly horizontally and in a southwest-northeast direction. These mechanisms are similar to those observed for earthquakes previously studied in the region on the basis of teleseismic data, such as the Mw 6.9, 29 August

  6. Analysis of 3-dimensional Hydro-dynamical Model Simulation in the Gulf of Kutch, India and Its Comparison with Satellite Data

    Digital Repository Service at National Institute of Oceanography (India)

    Osawa, T.; Zhao, C.; Kunte, P.D.; Ae, L.S.; Hara, M.; Moriyama, T.

    . The similar trend was also found in NOAA/AVHRR data. However the detail structure of sea surface temperature differs as satellites measures the skin temperature of water body whereas the model considers entire first layer. The sea surface temperature... is considered in the model simulation. The similar trend was also found in NOAA/AVHRR data. However the detail structure of sea surface temperature differs as satellites measures the skin temperature of water body whereas the model considers entire first...

  7. Monosodium Luminol for Improving Brain Function in Gulf War Illness

    Science.gov (United States)

    2015-10-01

    whether administration of monosodium luminol-GVT (MSL-GVT, an antioxidant drug from Bach Pharma) in a rat model of Gulf war illness (GWI) would...antioxidant and anti-inflammatory drug monosodium luminol-GVT (MSL-GVT from Bach Pharma) for easing memory and mood dysfunction in a rat model of GWI...examine the efficacy of monosodium luminol-GVT (MSL-GVT from Bach Pharma) for alleviating mood and memory dysfunction in a rat model of GWI. The chosen

  8. Leviathan moving to expand Gulf gas system

    Energy Technology Data Exchange (ETDEWEB)

    1992-06-15

    This paper reports that Leviathan Gas Pipeline Co., Houston, has advanced plans for a large deepwater pipeline gathering system in the Gulf of Mexico. Under an agreement between Deep-Tech International Inc. and Transco Energy Co., Leviathan will pay $65 million for Transco interests in several gulf gas gathering pipelines and related facilities. Leviathan is a Deep Tech subsidiary. Gulf pipeline assets Leviathan acquired from Transco include Louisiana Offshore Pipeline Systems (LOPS), Green Canyon Pipeline Co., and companies owning at 40% interest in High Island Offshore System (HIOS) and a 33 1/1% interest in United Texas Offshore System (UTOS).

  9. Gulf of Mexico soundscapes as indicators of ecological stressors

    Science.gov (United States)

    Sidorovskaia, N.; Li, K.; Tiemann, C.; Ackleh, A. S.; Tang, T.; Risbourg, J. H.

    2016-12-01

    Soundscapes in the Northern Gulf of Mexico are complex and represent a combination of anthropogenic noise (oil exploration and production, shipping, rig construction, etc.), bio-soundscapes (sound of marine mammals and fish), and geo-soundscapes (weather events, submarine landslides, distant earthquakes, natural gas seeps). We will discuss how Passive Acoustic Monitoring in the deep Gulf has been utilized during the past decade to study the soundscape variability on daily, monthly, and yearly timescales and what environmental information can be extracted from this variability. Isolation of bio-soundscapes, identification of their sources, and abundance estimates based on acoustic cues are used to track the recovery of marine mammal species after major ecological disasters, such as the recent 2010 oil spill. Association of acoustic activity of marine species with anthropogenic noise levels and other environmental variables can provide base data that can be used to build ecological models of habitat preferences for different marine species. Understanding how the variability of anthropogenic soundscapes correlates with marine species distributions is critically important for regional conservation and mitigation strategies. Such studies can also assist in forecasting the long-term ecosystem health status and ecosystem response to disturbances of different spatial and temporal extent, including slow variations associated with climate change. [This research was made possible in part by a grant from The Gulf of Mexico Research Initiative, and in part by funding provided by ONR and The Joint Industry Programme.

  10. Experimental evaluation of nutrient limitation of phytoplankton communities in the Gulf of Riga

    Science.gov (United States)

    Seppälä, J.; Tamminen, T.; Kaitala, S.

    1999-12-01

    Phytoplankton nutrient limitation was studied in the Gulf of Riga during spring bloom (April 1995), early summer stage (June 1994), cyanobacterial bloom (July 1994) and post cyanobacterial bloom (August 1993). Each year six factorial nutrient enrichment experiments were carried out in various locations in the Gulf; including outer Irbe Strait, northern Gulf and southern Gulf. The responses of natural phytoplankton communities to the nutrient additions (80 μg NH 4-N l -1, 20 μg PO 4-P l -1 and two levels of combined additions) were followed for 3 days using 6 l experimental units. To evaluate the nutrient limitation patterns, time series of chlorophyll a were analysed using polynomial regression models and ranking method, taking advantage of the relatively constant experimental error. Apparent nutrient depletion rates and ratios were estimated, and compared with the changes in particulate nutrient ratios. During the spring diatom bloom in 1995, ambient inorganic nutrient concentrations were still high, and thus phytoplankton biomass did not respond to additions of nutrients. Chlorophyll a specific nutrient depletion rates were low (0.01-0.12 μg N (μg chl a) -1 h -1 and 0.002-0.016 μg P (μg chl a) -1 h -1) and linear over time, thus also revealing that phytoplankton was not limited by these nutrients in that time. In June 1994, there was an areal shift from N limitation in the outer Irbe Strait towards co-limitation in the southern Gulf. Later in July 1994, during the bloom of N-fixing Aphanizomenon flos-aquae, the N limitation was obvious for the whole study area. For this period chlorophyll a specific nutrient depletion rates were high (0.36-0.67 μg N (μg chl a) -1 h -1 and 0.089-0.135 μg P (μg chl a) -1 h -1), and added nutrients were almost totally depleted during the first light period. After the collapse of cyanobacterial bloom in August 1993, the experiment carried out in the southern Gulf indicated P limitation of phytoplankton. The central Gulf was

  11. The vertical distribution of physical parameters in the Gulf of Riga for future climate projections.

    Science.gov (United States)

    Valainis, Aigars; Sennikovs, Juris

    2010-05-01

    Our goal was to investigate the vertical distribution of physical parameters (temperature, salinity) in the Gulf of Riga for the contemporay climate and for future climate projections. The Gulf of Riga is a semi-enclosed subbasin of the Baltic Sea between Latvia and Estonia. The area of the Gulf of Riga is about 18,000 sq. km. The maximum depth is 67 m. The island of Saaremaa partially separates it from the rest of the Baltic Sea. The main connection of the Gulf with the Baltic Proper is the Irbe Strait allowing limited exchanges with Baltic see. The Gulf of Riga was modelled with 1D model. Calculations were made for 55 m deep water column, taking into account hypsographic curve. The General Ocean Turbulence Model (GOTM) was used. Second order dynamic k-e equation with parameterization from Cheng (2002) was used for turbulence description. The result sensitivity was evaluated regarding models choice. Data from European Centre for Medium-Range Weather Forecasts (ECMWF) where used for calibration and verification period. Data included ECMWF ERA 40 for time period 1957-2002, and ECMWF ERA Interim for 1989-2009. Regional climate models (RCM) and scenarios for future climate change were obtained from Prediction of Regional scenarios and Uncertainties for Defining European Climate change risks and Effects (PRUDENCE) project. Time period for future physical parameter vertical distribution simulation was 2071-2100. We applied the bias correction (via histogram equalisation) of RCM data. We employed the setup of hydrological models to generate the contemporary and future river run-off data series Our results conclude that in future the Gulf won't freeze over. In summer surface temperature will increase at least by 2 degrees Celsius. Vertical stratification will begin a month earlier - as a consequence the time period of full mixing will be shorter.

  12. Estimating hydrologic budgets for six Persian Gulf watersheds, Iran

    Science.gov (United States)

    Hosseini, Majid; Ghafouri, Mohammad; Tabatabaei, MahmoudReza; Goodarzi, Masoud; Mokarian, Zeinab

    2016-10-01

    Estimation of the major components of the hydrologic budget is important for determining the impacts on the water supply and quality of either planned or proposed land management projects, vegetative changes, groundwater withdrawals, and reservoir management practices and plans. As acquisition of field data is costly and time consuming, models have been created to test various land use practices and their concomitant effects on the hydrologic budget of watersheds. To simulate such management scenarios realistically, a model should be able to simulate the individual components of the hydrologic budget. The main objective of this study is to perform the SWAT2012 model for estimation of hydrological budget in six subbasin of Persian Gulf watershed; Golgol, Baghan, Marghab Shekastian, Tangebirim and Daragah, which are located in south and south west of Iran during 1991-2009. In order to evaluate the performance of the model, hydrological data, soil map, land use map and digital elevation model (DEM) are obtained and prepared for each catchment to run the model. SWAT-CUP with SUFI2 program was used for simulation, uncertainty and validation with 95 Percent Prediction Uncertainty. Coefficient of determination (R 2) and Nash-Sutcliffe coefficient (NS) were used for evaluation of the model simulation results. Comparison of measured and predicted values demonstrated that each component of the model gave reasonable output and that the interaction among components was realistic. The study has produced a technique with reliable capability for annual and monthly water budget components in Persian Gulf watershed.

  13. Alternative diagenetic models for cretaceous talus deposits, Deep Sea Drilling Project Site 536, Gulf of Mexico: Chapter 8 in Initial reports of the Deep Sea Drilling Project

    Science.gov (United States)

    Halley, Robert B.; Pierson, B. J.; Schlager, Wolfgang

    1984-01-01

    Talus deposits recovered from Site 536 show evidence of aragonite dissolution, secondary porosity development, and calcite cementation. Although freshwater diagenesis could account for the petrographic features of the altered talus deposits, it does not uniquely account for isotopic or trace-element characteristics. Also, the hydrologic setting required for freshwater alteration is not easily demonstrated for the Campeche Bank. A mixing-zone model does not account for the available trace-element data, but does require somewhat less drastic assumptions about the size of the freshwater lens. Although a seawater (bottom-water) alteration model requires no hydrologic difficulties, unusual circumstances are required to account for the geochemical characteristics of the talus deposits using this model.

  14. Oil-material fractionation in Gulf deep water horizontal intrusion layer: Field data analysis with chemodynamic fate model for Macondo 252 oil spill.

    Science.gov (United States)

    Melvin, A T; Thibodeaux, L J; Parsons, A R; Overton, E; Valsaraj, K T; Nandakumar, K

    2016-04-15

    Among the discoveries of the Deepwater Horizon blowout was the so-called "sub-surface plume"; herein termed the "oil-trapping layer". Hydrocarbons were found positioned at ~1100-1300m with thickness ~100-150m and moving horizontally to the SW in a vertically stratified layer at the junction of the cold abyssal water and the permanent thermocline. This study focuses on its formation process and fate of the hydrocarbons within. The originality of this work to the field is two-fold, first it provides a conceptual framework which places layer origin in the context of a horizontal "intrusion" from the near-field, vertical, blow-out plume and second, it offers a theoretical model for the hydrocarbon chemicals within the horizontal layer as it moves far-afield. The model quantifies the oil-material fractionation process for the soluble and fine particle. The classical Box model, retrofitted with an internal gradient, the "G-Box", allows an approach that includes turbulent eddy diffusion coupled with droplet rise velocity and reactive decay to produce a simple, explicit, transparent, algebraic model with few parameters for the fate of the individual fractions. Computations show the soluble and smallest liquid droplets moving very slowly vertically through the layer appearing within the trapping layer at low concentration with high persistence. The larger droplets move-through this trapping zone quickly, attain high concentrations, and eventually form the sea surface slick. It impacts the field of oil spill engineering science by providing the conceptual idea and the algorithms for projecting the quantities and fractions of oil-material in a deep water, horizontal marine current being dispersed and moving far afield. In the field of oil spill modeling this work extends the current generation near-field plume source models to the far-field. The theory portrays the layer as an efficient oil-material trap. The model-forecasted concentration profiles for alkanes and aromatics

  15. Gulf of Mexico Nutrient, carbon, CTD data

    Data.gov (United States)

    U.S. Environmental Protection Agency — Gulf of Mexico cruise, nearshore and CTD data collected by the USEPA during 2002 - 2008. This dataset is associated with the following publications: Pauer , J., T....

  16. Gulf Coast Vulnerability Assessment and Conservation Framework

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The proposed partnership to support a Gulf Coast Landscape Conservation Liaison will provide much needed coordination across multiple programs and partnerships to...

  17. Cretaceous Onlap, Gulf of Mexico Basin [cretonlapg

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The maximum extent of Cretaceous onlap is generalized from Plate 3, Structure at the base and subcrop below Mesozoic marine section, Gulf of Mexico Basin (compiled...

  18. Anticlines in the US Gulf Coast [anticlineg

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset of anticlines is intended primarily for reference; it includes major structures such as those shown on Plate 2, Principal structural features, Gulf of...

  19. Central Gulf of Alaska Rockfish Permit Program

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The North Pacific Fishery Management Council adopted the Central Gulf of Alaska Rockfish Program (Rockfish Program) on June 14, 2010, to replace the expiring Pilot...

  20. 2013 Gulf of Mexico SPCE angler survey

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This survey provides economic data related to marine recreational fishing in the Gulf of Mexico. The data collected include preference and opinion information...

  1. Gulf of Mexico Deepwater Bathymetry Contours

    Data.gov (United States)

    Bureau of Ocean Energy Management, Department of the Interior — Gulf of Mexico Depth Contours derived from NOAA's NGDC bathymetric grids and from BOEM's seismic grid compilation. Both NOAA and BOEM contours are shown in meters or...

  2. Southeast Gulf of Mexico Sperm Whale Study

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Large vessel surveys were conducted during the summers of 2012 and 2014 in the southeastern Gulf of Mexico north of the Dry Tortugas. Data were collected on the...

  3. ROE Gulf of Mexico Hypoxia Sample Locations

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset describes dissolved oxygen levels in the Gulf of Mexico. Individual sampling sites are represented by point data. The background polygon shows areas...

  4. Gulf of Mexico Ecosystem Status Report

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Gulf of Mexico is one of the most ecologically and economically valuable marine ecosystems in the world and is affected by a variety of natural and anthropogenic...

  5. Volcanics in the Gulf Coast [volcanicg

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The volcanic provinces are modified after Plate 2, Principal structural features, Gulf of Mexico Basin (compiled by T.E. Ewing and R.F. Lopez) in Volume J, The...

  6. Gulf War Illness Inflammation Reduction Trial

    Science.gov (United States)

    2015-10-01

    1 AWARD NUMBER: W81XWH-14-1-0477 TITLE: Gulf War Illness Inflammation Reduction Trial PRINCIPAL INVESTIGATOR: Ronald R. Bach, Ph.D...5a. CONTRACT NUMBER Gulf War Illness Inflammation Reduction Trial 5b. GRANT NUMBER W81XWH-14-1-0477 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d...GWI). Elevated biomarkers of inflammation were observed in our pilot observational study of GWI. Thus, chronic inflammation appears to be part of

  7. Qatar Peninsula, United Arab Emirates, Persian Gulf

    Science.gov (United States)

    1983-01-01

    In this view of the Qatar Peninsula, United Arab Emirates, Persian Gulf, (25.0N, 51.0E) a large oil spill, seen as a large dark toned mass in the water covers much of the surface of the western Persian Gulf. Qatar is one of several of the oil rich United Arab Emirate states. Oil spills and oil pollution of the environment are common occurrances associated with oil tanker loading operations.

  8. Probiotic (VSL#3) for Gulf War Illness

    Science.gov (United States)

    2014-10-01

    efforts are ongoing to recruit more Gulf War veterans. The first set of stool samples have been sent to Lawrence Berkeley Laboratory microbiota analysis...There is scientific evidence that probiotics by restoring normal gut flora improve symptoms of IBS. Probiotics have also been shown to improve...the Lawrence Berkeley laboratory for microbiota analysis.  We have received the list of Gulf War Veterans in the Salt Lake City are from the Defense

  9. The Gulf Stream front - A comparison between Seasat altimeter observations and theory

    Science.gov (United States)

    Kao, T. W.; Cheney, R. E.

    1982-01-01

    A quantitative comparison is made between a model which gives a universal shape and width of the sea surface height rise anomaly across the Gulf Stream and six Gulf Stream altimeter profiles representing a range of conditions. The closeness of the fit obtained reinforces the validity of both the model and the role of satellite altimetry in ocean dynamics. Further comparisons of the data with the theories of Stommel (1966) and Charney (1955) show that the former is incomplete, accepting only one altimeter-derived parameter.

  10. Suspended sediment transport in the Gulf of Lions (NW Mediterranean): Impact of extreme storms and floods

    NARCIS (Netherlands)

    Ulses, C.; Estournel, C.; Durrieu de Madron, X.; Palanques, A.

    2008-01-01

    In situ observations were combined with 3D modeling to gain understanding of and to quantify the suspended sediment transport in the Gulf of Lions (NW Mediterranean Sea). The outputs of a hydrodynamic–sediment transport coupled model were compared to near-bottom current and suspended sediment

  11. A finite element simulation of tidal circulation in the Gulf of Kutch, India

    Digital Repository Service at National Institute of Oceanography (India)

    Unnikrishnan, A.S.; Luick, J.L.

    A finite element (fe) model using the software package ADCTRC was developed to simulate the tides and currents in the Gulf of Kutch, located on the northwest coast of India. The surface elevations from the model were analysed for the amplitudes...

  12. Comment on "Deep structure, recent deformation and analog modeling of the Gulf of Cadiz accretionary wedge: Implications for the 1755 Lisbon earthquake", by Gutscher et al. 2009

    Science.gov (United States)

    Marques, F. O.

    2010-04-01

    Gutscher et al. (2009b) address a very interesting and unsolved problem, which is the continuation of the Azores-Gibraltar plate boundary to the E of the Gorringe Bank. This comment comprises three parts: (1) short introduction to the geologic setting; (2) comment on the analogue modelling, the relationship of the setup with the prototype, and the relationship of the experimental results with the prototype; (3) short discussion of proposed subduction to the E.

  13. Simulation of oil pollution in the Persian Gulf near Assaluyeh oil terminal.

    Science.gov (United States)

    Faghihifard, M; Badri, M A

    2016-04-15

    Numerical simulation of oil slick movement with respect to tidal factors and wind effects was performed in order to counteract oil pollution in the Persian Gulf. First, a flow model was invoked with respect to water level fluctuations. The main tidal constituents were applied to the model using the initial conditions of water level variations in the Hormuz Strait near the Hangam Island. The movement of oil pollution was determined due to wind, tide and temperature effects and confirmed by applying a verified field results. Simulations were focused near an important terminal in the Persian Gulf, Assaluyeh Port. The results were led to preparing a risk-taking map in a parallel research for the Persian Gulf.

  14. Simulated Impacts of Juvenile Mortality on Gulf of Mexico Sturgeon Populations

    Directory of Open Access Journals (Sweden)

    William B. Tate

    2002-01-01

    Full Text Available We used an age-structured computer model to assess the impact of changes in juvenile mortality on the Gulf of Mexico sturgeon population in the Suwannee River, Florida. We simulated population trends under four levels of annual juvenile mortality (20, 25, 30, and 35%. As the rate of mortality increased, population size decreased, and rates of population growth shifted from positive to negative. Our models indicated that juvenile survival is important to the success of gulf sturgeon populations, and mortality estimates are needed to predict population viability. We suggest that life history studies in estuaries should be conducted, and bycatch rates for commercial fisheries should be quantified to aid in the management and conservation of gulf sturgeon.

  15. A Markov model for planning and permitting offshore wind energy: A case study of radio-tracked terns in the Gulf of Maine, USA.

    Science.gov (United States)

    Cranmer, Alexana; Smetzer, Jennifer R; Welch, Linda; Baker, Erin

    2017-05-15

    Quantifying and managing the potential adverse wildlife impacts of offshore wind energy is critical for developing offshore wind energy in a sustainable and timely manner, but poses a significant challenge, particularly for small marine birds that are difficult to monitor. We developed a discrete-time Markov model of seabird movement around a colony site parameterized by automated radio telemetry data from common terns (Sterna hirundo) and Arctic terns (S. paradisaea), and derived impact functions that estimate the probability of collision fatality as a function of the distance and bearing of wind turbines from a colony. Our purpose was to develop and demonstrate a new, flexible tool that can be used for specific management and wind-energy planning applications when adequate data are available, rather than inform wind-energy development at this site. We demonstrate how the tool can be used 1) in marine spatial planning exercises to quantitatively identify setback distances under development scenarios given a risk threshold, 2) to examine the ecological and technical trade-offs of development alternatives to facilitate negotiation between objectives, and 3) in the U.S. National Environmental Policy Act (NEPA) process to estimate collision fatality under alternative scenarios. We discuss model limitations and data needs, and highlight opportunities for future model extension and development. We present a highly flexible tool for wind energy planning that can be easily extended to other central place foragers and data sources, and can be updated and improved as new monitoring data arises. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. The Role of Protein Radicals in Chronic Neuroimmune Dysfunction and Neuropathology in Response to a Multiple-Hit Model of Gulf War Exposures

    Science.gov (United States)

    2015-10-01

    on the key molecular target NF-κB p50 in CNS effects. Experiments employing a mouse model of GWI for short term and long term analysis of the brain...exposures that focuses on the key molecular target, NF-κB p50 in the brain. NF-κB is a redox- sensitive, prototypical pro-inflammatory transcription...presentation for the Central Virginia Society for Neuroscience meeting, Richmond, VA D. Block ML. (April, 2015). Invited Speaker for the Motor Neuron

  17. Major reproductive health characteristics in male Gulf War Veterans. The Danish Gulf War Study

    DEFF Research Database (Denmark)

    Ishøy, T; Andersson, A M; Suadicani, Poul Vilhelm

    2001-01-01

    The male reproductive system could have been affected by various hazardous agents and exposures during and in the aftermath of the Persian Gulf War scenario. We tested the hypothesis that, compared to controls, male Danish Gulf War Veterans would have adverse sex hormone levels, decreased fertility...

  18. Salinity Measurements During the Gulf Stream Experiment

    Science.gov (United States)

    LeVine, D. M.; Koblinsky, C.; Howden, S.; Goodberlet, M.

    2000-01-01

    The salinity of the open ocean is important for understanding ocean circulation, for understanding energy exchange with the atmosphere and for improving models to predict weather and climate. Passive microwave sensors at L-band (1.4 GHz) operating from aircraft have demonstrated that salinity can be measured with sufficient accuracy (1 psu) to be scientifically meaningful in coastal waters. However, measuring salinity in the open ocean presents unresolved issues largely because of the much greater accuracy (approx. 0.1 psu) required to be scientifically viable. In the summer of 1999 a series of measurements called, The Gulf Stream Experiment, were conducted as part of research at the Goddard Space Flight Center to test the potential for passive microwave remote sensing of salinity in the open ocean. The measurements consisted of a compliment of airborne microwave instruments (radiometers and scatterometer) and ships and drifters for surface truth. The study area was a 200 km by 100 km rectangle about 250 km east of Delaware Bay between the continental shelf waters and north wall of the Gulf Stream. The primary passive instruments were the ESTAR radiometer (L-band, H-pol) and the SLFMR radiometer (L-band, V-pol). In addition, the compliment of instruments on the aircraft included a C-band radiometer (ACMR), an ocean wave scatterometer (ROWS) and an infrared radiometer. A GPS backscatter experiment was also part of the package. These instruments were mounted on the NASA P-3 Orion aircraft. Surface salinity measurements were provided by the RN Cape Henlopen and MN Oleander (thermosalinographs) plus salinity and temperature sensors on three surface drifters deployed from the RN Cape Henopen. The primary experiment period was August 26-September 2, 1999. During this period the salinity field within the study area consisted of a gradient on the order of 2-3 psu in the vicinity of the shelf break and a warm core ring with a gradient of 1-2 psu. Detailed maps were made

  19. Larval Fish Assemblages, Environment and Circulation in a Semienclosed Sea (Gulf Of California).

    Science.gov (United States)

    Peguero, M.; Sánchez-Velasco, L.; Lavín, M.; Marinone, G.

    2007-05-01

    Fish larvae and hydrographic data collected in the Gulf of California in December 2002 are used to describe the larval fish assemblages and to explore their relationships with environmental variables. The Bray-Curtis dissimilarity index defined three larval fish assemblages, whose goeographical distribution coincided with three areas defined by Principal Component Analysis of the environmental variables. The affinity of most of the species with the environmental characteristics of their areas of distribution could be interpreted as an indication that spawning occurred inside those areas. However, it is not known when the spawning took place, and the fast currents in the Gulf could rapidly disperse eggs and larvae. Since transport and retention is best studied from a Lagrangian point of view, the currents from a 3D numerical model were used to track large numbers of particles released in the different larval fish assemblage areas. Particle-tracking and connectivity matrices can help in assessing larval fish retention in seas that, like the Gulf of California, have well defined circulation patterns. On time scales around 30 days, retention occurred for the North assemblage in the Upper Gulf, for the Channel- Central assemblage in the anticyclone over the Norhern Gulf and in Ballenas Channel, and for the South assemblage in the eddy over San Pedro Mártir basin and in the shallow zone off the peninsula. Therefore, the Lagrangian analysis revealed that the observed larval fish assemblages have a permanency long enough to allow the larve to remain in a favorable environment until they develop motility.

  20. MEASURED AND PREFORMED PHOSPHATE IN THE GULF OF MEXICO REGION.

    Science.gov (United States)

    Measured and preformed phosphate-phosphorous versus depth are presented for three recent cruises to the Gulf of Mexico region. Phosphate...are discussed for a hypothetical idealized station in the Gulf of Mexico . (Author)

  1. Gulf of Mexico Hydrocarbon Seeps (SEEPS.SHP)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This GIS overlay is a component of the U.S. Geological Survey, Woods Hole Science Center's, Gulf of Mexico GIS database. The Gulf of Mexico GIS database is intended...

  2. In-theater hospitalizations of US and allied personnel during the 1991 Gulf War.

    Science.gov (United States)

    Smith, Tyler C; Corbeil, Thomas E; Ryan, Margaret A K; Heller, Jack M; Gray, Gregory C

    2004-06-01

    The postwar morbidity of Gulf War veterans has been closely examined. However, data have not been available to evaluate morbidity suffered during the 1991 Gulf War. In this report, the authors examine archived records of hospitalizations in US military facilities in the Kuwaiti theater of operations or those medically evacuated to facilities in Europe. Using multivariable logistic regression modeling, the authors determined that service personnel at greatest odds for "in-theater" hospitalization were enlisted, female, White, Reservist, Army, and health care workers. No increase in odds was observed for oil well fire smoke exposure or possible exposure to the nerve agent hazard areas. Although these data may be incomplete, they represent the best-known data reflecting in-theater hospitalizations during the Gulf War of 1991 and show remarkable similarities in risk factors to those for postwar hospitalization.

  3. Crustal structure of the Eastern Gulf of Mexico

    Science.gov (United States)

    Nwafor, Emeka

    The Gulf of Mexico initiated in the Late Triassic as South America and Africa separated from North America during the break up of Pangea. Previous studies indicate three models for the opening of the GOM. These include counter clockwise rotation of the Yucatan Block, rotation of the Yucatan Block about the same pole of rotation as those describing seafloor spreading in the central North Atlantic, and clockwise rotation of the Yucatan Block. There is much debate about the margin type and the crustal structure of the Eastern Gulf of Mexico (EGOM), especially below the depth of 6 km where crustal structure is poorly imaged on seismic reflection data. Two 2.5-D forward gravity and magnetic models across the margin are presented. These are constrained by basement picks from sparse seismic reflection and refraction data, spectral analysis of gravity data to determine the depth to source, magnetic susceptibility derived from results from other margins, the empirical relationship between P-wave velocity and density, and crustal scale isostatic modeling. The models, combined with a kinematic reconstruction of the GOM, show that: 1) it is a rifted margin; 2) the point where the Moho deepens downward from ˜17 km to ˜32 km is approximately 50 km outboard of the topographic shelf edge; 3) the carbonate bank retreated by several kilometers from its original termination due to the action of contourite currents; 4) extension and subsidence was accommodated with little shallow brittle faulting; 5) oceanic lithosphere is possibly outboard of the EGOM continental slope.

  4. Tidal propagation in the Gulf of Khambhat, Bombay High, and surrounding areas

    Digital Repository Service at National Institute of Oceanography (India)

    Unnikrishnan, A.S.; Shetye, S.R.; Michael, G.S.

    -diurnal and diurnal constituents at forty-two ports in the Gulf and surrounding areas is sued to define characteristics of the tides. A barotropic numerical model based on shallow water wave equations to simulate the sea level and circulation in the region is used...

  5. 75 FR 64171 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Reef Fish Fishery of the Gulf of...

    Science.gov (United States)

    2010-10-19

    ... reached by October 28, 2010. This closure is necessary to prevent overfishing of Gulf greater amberjack... legal requirements to prevent and end overfishing and rebuild greater amberjack in the Gulf. On August 4... prevent overfishing of Gulf greater amberjack and increase the likelihood that the 2010 quota will not...

  6. 76 FR 54727 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Spiny Lobster Fishery of the Gulf...

    Science.gov (United States)

    2011-09-02

    ... Caribbean, Gulf of Mexico, and South Atlantic; Spiny Lobster Fishery of the Gulf of Mexico and South... Fishery Management Plan for the Spiny Lobster Fishery of the Gulf of Mexico and South Atlantic (FMP) for review, approval, and implementation by NMFS. Amendment 10 proposes actions to revise the lobster...

  7. Symptom Patterns Among Gulf War Registry Veterans

    Science.gov (United States)

    Hallman, William K.; Kipen, Howard M.; Diefenbach, Michael; Boyd, Kendal; Kang, Han; Leventhal, Howard; Wartenberg, Daniel

    2003-01-01

    Objectives. We identify symptom patterns among veterans who believe they suffer from Gulf War–related illnesses and characterize groups of individuals with similar patterns. Methods. A mail survey was completed by 1161 veterans drawn from the Gulf War Health Registry. Results. An exploratory factor analysis revealed 4 symptom factors. A K-means cluster analysis revealed 2 groups: (1) veterans reporting good health and few moderate/severe symptoms, and (2) veterans reporting fair/poor health and endorsing an average of 37 symptoms, 75% as moderate/severe. Those in Cluster 2 were more likely to report having 1 or more of 24 medical conditions. Conclusions. These findings are consistent with previous investigations of symptom patterns in Gulf War veterans. This multisymptom illness may be more fully characterized by the extent, breadth, and severity of symptoms reported. PMID:12660208

  8. Climate change impact on wave energy in the Persian Gulf

    Science.gov (United States)

    Kamranzad, Bahareh; Etemad-Shahidi, Amir; Chegini, Vahid; Yeganeh-Bakhtiary, Abbas

    2015-06-01

    Excessive usage of fossil fuels and high emission of greenhouse gases have increased the earth's temperature, and consequently have changed the patterns of natural phenomena such as wind speed, wave height, etc. Renewable energy resources are ideal alternatives to reduce the negative effects of increasing greenhouse gases emission and climate change. However, these energy sources are also sensitive to changing climate. In this study, the effect of climate change on wave energy in the Persian Gulf is investigated. For this purpose, future wind data obtained from CGCM3.1 model were downscaled using a hybrid approach and modification factors were computed based on local wind data (ECMWF) and applied to control and future CGCM3.1 wind data. Downscaled wind data was used to generate the wave characteristics in the future based on A2, B1, and A1B scenarios, while ECMWF wind field was used to generate the wave characteristics in the control period. The results of these two 30-yearly wave modelings using SWAN model showed that the average wave power changes slightly in the future. Assessment of wave power spatial distribution showed that the reduction of the average wave power is more in the middle parts of the Persian Gulf. Investigation of wave power distribution in two coastal stations (Boushehr and Assalouyeh ports) indicated that the annual wave energy will decrease in both stations while the wave power distribution for different intervals of significant wave height and peak period will also change in Assalouyeh according to all scenarios.

  9. Structural framework of the Gulf of Elat (AQABA), Northern Red Sea

    Science.gov (United States)

    Ben-Avraham, Zvi

    1985-01-01

    The Gulf of Elat (Aqaba) occupies the southern part of the Dead Sea rift. The rift is considered to be a plate boundary of the transform type (partially leaky) which connects seafloor spreading in the Red Sea with the Sagros-Taurus zone of continental collision. The deep water in the Gulf of Elat, up to 1850 m, provides a rare opportunity to examine the process of continental rifting by marine geophysical techniques. The bathymetry alone provides much information about fault patterns in this area. The fragmentation of the once continuous Arabian-African platform is a complicated process. It shapes the structure of the gulf which has developed through continuing tectonism, primarily consisting of faulting. Recent geophysical and geological studies of the Gulf of Elat including bathymetry, bottom photographs, continuous seismic profiles, seismic refraction, gravity, magnetics, heat flow, and coring provide new information about the shallow and deep crustal structure of this important segment of the world rift system. The shallow structure of the gulf is dominated by three elongated en echelon basins, which strike N20°-25°E. Undulations in the floors of the basins produce several distinct deeps. These basins are interpreted as pullaparts. The new data from the gulf suggest that classical models for the formation of these structures should be modified. Only one of the longitudinal faults of each depression is a strike-slip fault, while the other is predominantly a normal fault. The situation with the other two sides of the basin which are supposed to be composed of normal faults may also be more complex than previously thought. At least in one case, one such boundary is composed of a strike-slip fault while the other has no significant fault. Crustal models of the Gulf of Elat based on gravity data indicate that the basins are rather shallow and do not extend into the lower crust. The fill of the basins extends to about 5 km below the seafloor in. the northern and

  10. Thermochronological investigation of the timing of rifting and rift segmentation in the Gulf of Suez, Egypt

    Science.gov (United States)

    Bosworth, W.; Stockli, D. F.

    2006-12-01

    The Tertiary Gulf of Suez rift system is one of the best-studied continental rift systems and has inspired many fundamental geodynamic models for continental rifting. However, our limited knowledge of how extensional strain is spatially and temporally distributed has made it difficult to adequately evaluate models for the dynamic evolution of this rift. A critical aspect of constraining the evolution of rifting and rift segmentation in the Gulf of Suez involves acquiring reliable geochronological constraints on extensional faulting. This study has commenced a systematic investigation of the timing and spatial distribution of rifting, lateral rift segmentation, and rift localization within the Gulf of Suez, Egypt, employing apatite and zircon (U-Th)/He thermochronometry. (U-Th)/He thermochronometric analysis of sample transects from exhumed fault blocks within the rift integrated with structural data will allow us to directly determine the timing, distribution, and magnitude of extension. The onset of major rifting (~24-19 Ma) in the Gulf of Suez was marked by the development of crustal domino-style tilt blocks and syn-rift deposition of the late Oligocene non-marine Abu Zenima Fm and non-marine to restricted marine Nukhul Fm. Development of the Gulf of Aqaba-Dead Sea transform cut off the rift from the Red Sea rift at an early extensional stage. Apatite (AHe) and zircon (ZHe) (U- Th)/He data were collected from basement and pre-rift sedimentary sample transects from the central and southern Sinai Peninsula portion and the Gebel El Zeit area in the southern Gulf of Suez as well as from basement samples from selected drill cores off Gebel El Zeit. Preliminary data exhibit partially reset ages trending as old as ~70 Ma (AHe) and ~450 Ma (ZHe) from shallower structural levels (Proterozoic basement and Phanerozoic cover sequence). Structurally deeper samples yield abundant AHe ages of ~22-24 Ma, indicative of rapid cooling and exhumation during the early Miocene. More

  11. Probiotic (VSL 3) for Gulf War Illness

    Science.gov (United States)

    2015-10-01

    AD_________________ Award Number: W81XWH-10-1-0593 TITLE: Probiotic (VSL#3) for Gulf War Illness PRINCIPAL INVESTIGATOR: Ashok Tuteja, M.D...2015 5a. CONTRACT NUMBER Probiotic (VSL#3) for Gulf War Illness 5b. GRANT NUMBER W81XWH-10-1-0593 5c. PROGRAM ELEMENT NUMBER 6 . AUTHOR(S) 5d...ABSTRACT The overall objective of the study is to determine whether probiotic VSL#3® will improve 1) intestinal symptoms of Irritable Bowel Syndrome

  12. Gulf Coast Clean Energy Application Center

    Energy Technology Data Exchange (ETDEWEB)

    Dillingham, Gavin

    2013-09-30

    The Gulf Coast Clean Energy Application Center was initiated to significantly improve market and regulatory conditions for the implementation of combined heat and power technologies. The GC CEAC was responsible for the development of CHP in Texas, Louisiana and Oklahoma. Through this program we employed a variety of outreach and education techniques, developed and deployed assessment tools and conducted market assessments. These efforts resulted in the growth of the combined heat and power market in the Gulf Coast region with a realization of more efficient energy generation, reduced emissions and a more resilient infrastructure. Specific t research, we did not formally investigate any techniques with any formal research design or methodology.

  13. Shelf Circulation in the Gulf of Mexico.

    Science.gov (United States)

    2007-11-02

    Gulf of Mexico between 1990 and 1993, are used to describe the seasonal fluctuations in patterns of atmospheric variables from a contemporary set of measurements. Seasonal maps of wind stress based on these measurements resemble wind stress maps based on ship observations, as published by Elliot (1979), rather than maps based on analyses of numerical weather forecasts, as published by Rhodes et a. (1989), particularly near the western boundary of the Gulf. Seasonal maps of wind stress curl are characterized by positive curls over the western and southwestern

  14. Star Formation in the Gulf of Mexico

    CERN Document Server

    Armond, Tina; Bally, John; Aspin, Colin

    2011-01-01

    We present an optical/infrared study of the dense molecular cloud, L935, dubbed "The Gulf of Mexico", which separates the North America and the Pelican nebulae, and we demonstrate that this area is a very active star forming region. A wide-field imaging study with interference filters has revealed 35 new Herbig-Haro objects in the Gulf of Mexico. A grism survey has identified 41 Halpha emission-line stars, 30 of them new. A small cluster of partly embedded pre-main sequence stars is located around the known LkHalpha 185-189 group of stars, which includes the recently erupting FUor HBC 722.

  15. Star Formation in the Gulf of Mexico

    OpenAIRE

    Armond, Tina; Reipurth, Bo; Bally, John; Aspin, Colin

    2011-01-01

    We present an optical/infrared study of the dense molecular cloud, L935, dubbed "The Gulf of Mexico", which separates the North America and the Pelican nebulae, and we demonstrate that this area is a very active star forming region. A wide-field imaging study with interference filters has revealed 35 new Herbig-Haro objects in the Gulf of Mexico. A grism survey has identified 41 Halpha emission-line stars, 30 of them new. A small cluster of partly embedded pre-main sequence stars is located a...

  16. Gulf International Conference on Applied Mathematics 2013

    CERN Document Server

    Advances in Applied Mathematics

    2014-01-01

    This volume contains contributions from the Gulf International Conference in Applied Mathematics, held at the Gulf University for Science & Technology. The proceedings reflects the three major themes of the conference. The first of these was mathematical biology, including a keynote address by Professor Philip Maini. The second theme was computational science/numerical analysis, including a keynote address by Professor Grigorii Shishkin. The conference also addressed more general applications topics, with papers in business applications, fluid mechanics, optimization, scheduling problems, and engineering applications, as well as a keynote by Professor Ali Nayfeh.

  17. Recent changes to the Gulf Stream causing widespread gas hydrate destabilization.

    Science.gov (United States)

    Phrampus, Benjamin J; Hornbach, Matthew J

    2012-10-25

    The Gulf Stream is an ocean current that modulates climate in the Northern Hemisphere by transporting warm waters from the Gulf of Mexico into the North Atlantic and Arctic oceans. A changing Gulf Stream has the potential to thaw and convert hundreds of gigatonnes of frozen methane hydrate trapped below the sea floor into methane gas, increasing the risk of slope failure and methane release. How the Gulf Stream changes with time and what effect these changes have on methane hydrate stability is unclear. Here, using seismic data combined with thermal models, we show that recent changes in intermediate-depth ocean temperature associated with the Gulf Stream are rapidly destabilizing methane hydrate along a broad swathe of the North American margin. The area of active hydrate destabilization covers at least 10,000 square kilometres of the United States eastern margin, and occurs in a region prone to kilometre-scale slope failures. Previous hypothetical studies postulated that an increase of five degrees Celsius in intermediate-depth ocean temperatures could release enough methane to explain extreme global warming events like the Palaeocene-Eocene thermal maximum (PETM) and trigger widespread ocean acidification. Our analysis suggests that changes in Gulf Stream flow or temperature within the past 5,000 years or so are warming the western North Atlantic margin by up to eight degrees Celsius and are now triggering the destabilization of 2.5 gigatonnes of methane hydrate (about 0.2 per cent of that required to cause the PETM). This destabilization extends along hundreds of kilometres of the margin and may continue for centuries. It is unlikely that the western North Atlantic margin is the only area experiencing changing ocean currents; our estimate of 2.5 gigatonnes of destabilizing methane hydrate may therefore represent only a fraction of the methane hydrate currently destabilizing globally. The transport from ocean to atmosphere of any methane released--and thus its

  18. Crustal types, distribution of salt and the early evolution of the Gulf of Mexico basin

    Energy Technology Data Exchange (ETDEWEB)

    Buffler, R.T. (Univ. of Texas, Austin (USA))

    1990-05-01

    A new contour map on the top of basement shows the overall configuration of the entire Gulf of Mexico basin. Basement, as used here, is all rocks lying below (older than) the extensive Middle Jurassic (Callovian ) premarine evaporites (Louann Salt, etc.) plus the Late Jurassic oceanic crust in the deep part of the basin. The contour map combined with all other available geophysical data has been used to subdivide the gulf basin into four crustal types: continental, thick transitional, thin transitional, and oceanic crust. The broad region of transitional crust and the basic architecture of the basin shown by the map is believed to have formed mainly during a separate Middle Jurassic period of widespread attenuation of the entire gulf region. The area of thick transitional crust around the periphery of the northern gulf is characterized by broad basement highs and lows with wave lengths of 200-300 km. These features controlled the general distribution and thickness of salt and the overlying Jurassic through Lower Cretaceous rocks. In the area of thin transitional crust Mesozoic basins tend to be assymetrical and generally trend more parallel to the overall basin. The boundary between thin transitional crust and oceanic crust is characterized by various salt-related features. For example, the northwest and north-central boundaries are defined by two northeast trending salt-cored foldbelts, the Perdido and Mississippi fan foldbelts, respectively. The offset between the two foldbelts may represent a major transform boundary related to the northwest opening of the gulf basin. All these data put important constraints on models for early gulf evolution.

  19. Gulf of Maine intermediate water

    Energy Technology Data Exchange (ETDEWEB)

    Hopkins, T.S. (Brookhaven National Lab., Upton, NY); Garfield, N. III

    1979-01-01

    The thermohaline dynamics of the Gulf of Maine are analyzed from the two year, eight cruise, data set of Colton, Marak, Nickerson, and Stoddard (1968). Six water masses are described: the Maine Surface Water, Maine Intermediate Water, and the Maine Bottom Water as interior water masses; and the Scotian Shelf Water, the Slope Water, and the Georges Bank Water as exterior water masses. Particular attention is given to the formation and disposition of the Maine Intermediate Water. Salt balance, T-S volume, and T-S drift analyses are used to provide transport and mixing estimates for the year 1966. The Slope Water entered at depth through the Northeast Channel at a rate of 2600 km/sup 3//yr; while the Scotian Shelf Water entered the surface and intermediate layers, mostly during winter intrusions, at a rate of 5200 km/sup 3//yr. The surface and intermediate layers exported a total of 7900 km/sup 3//yr in a 3:5 ratio, respectively. The Maine Intermediate Water tends to collect over the Wilkinson Basin during the stratified season, to exit via the Great South Channel during early spring, and to exit via the Northeast Channel during spring and summer. Comparisons are made between the estimated winter heat loss of 280 Ly/d and the observed heat losses of 230 Ly/d (surface layers) and 360 Ly/d (surface and intermediate layers). A limit for the Scotian Shelf Water contribution is about -70 Ly/d. It is concluded that the Maine Intermediate Water is produced locally and that it is exported in significant quantities.

  20. Impact of remote oceanic forcing on Gulf of Alaska sea levels and mesoscale circulation

    Science.gov (United States)

    Melsom, Arne; Metzger, E. Joseph; Hurlburt, Harley E.

    2003-11-01

    We examine the relative importance of regional wind forcing and teleconnections by an oceanic pathway for impact on interannual ocean circulation variability in the Gulf of Alaska. Any additional factors that contribute to this variability, such as freshwater forcing from river runoff, are disregarded. The study is based on results from numerical simulations, sea level data from tide gauge stations, and sea surface height anomalies from satellite altimeter data. At the heart of this investigation is a comparison of ocean simulations that include and exclude interannual oceanic teleconnections of an equatorial origin. Using lagged correlations, the model results imply that 70-90% of the interannual coastal sea level variance in the Gulf of Alaska can be related to interannual sea levels at La Libertad, Equador. These values are higher than the corresponding range from sea level data, which is 25-55%. When oceanic teleconnections from the equatorial Pacific are excluded in the model, the explained variance becomes about 20% or less. During poleward propagation the coastally trapped sea level signal in the model is less attenuated than the observed signal. In the Gulf of Alaska we find well-defined sea level peaks in the aftermath of El Niño events. The interannual intensity of eddies in the Gulf of Alaska also peaks after El Niño events; however, these maxima are less clear after weak and moderate El Niño events. The interannual variations in eddy activity intensity are predominantly governed by the regional atmospheric forcing.

  1. Gulf Islands Wilderness study area : Gulf Island National Wildlife Refuges : Wilderness study report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is a brief report on a wilderness study area located in the Gulf Island National Wildlife Refuges. It discusses the history of the study area, its...

  2. Hurricane Risk Variability along the Gulf of Mexico Coastline

    Science.gov (United States)

    Trepanier, Jill C.; Ellis, Kelsey N.; Tucker, Clay S.

    2015-01-01

    Hurricane risk characteristics are examined across the U. S. Gulf of Mexico coastline using a hexagonal tessellation. Using an extreme value model, parameters are collected representing the rate or λ (frequency), the scale or σ (range), and the shape or ξ (intensity) of the extreme wind distribution. These latent parameters and the 30-year return level are visualized across the grid. The greatest 30-year return levels are located toward the center of the Gulf of Mexico, and for inland locations, along the borders of Louisiana, Mississippi, and Alabama. Using a geographically weighted regression model, the relationship of these parameters to sea surface temperature (SST) is found to assess sensitivity to change. It is shown that as SSTs increase near the coast, the frequency of hurricanes in these grids decrease significantly. This reinforces the importance of SST in areas of likely tropical cyclogenesis in determining the number of hurricanes near the coast, along with SSTs along the lifespan of the storm, rather than simply local SST. The range of hurricane wind speeds experienced near Florida is shown to increase with increasing SSTs (insignificant), suggesting that increased temperatures may allow hurricanes to maintain their strength as they pass over the Florida peninsula. The modifiable areal unit problem is assessed using multiple grid sizes. Moran’s I and the local statistic G are calculated to examine spatial autocorrelation in the parameters. This research opens up future questions regarding rapid intensification and decay close to the coast and the relationship to changing SSTs. PMID:25767885

  3. Hurricane risk variability along the Gulf of Mexico coastline.

    Directory of Open Access Journals (Sweden)

    Jill C Trepanier

    Full Text Available Hurricane risk characteristics are examined across the U. S. Gulf of Mexico coastline using a hexagonal tessellation. Using an extreme value model, parameters are collected representing the rate or λ (frequency, the scale or σ (range, and the shape or ξ (intensity of the extreme wind distribution. These latent parameters and the 30-year return level are visualized across the grid. The greatest 30-year return levels are located toward the center of the Gulf of Mexico, and for inland locations, along the borders of Louisiana, Mississippi, and Alabama. Using a geographically weighted regression model, the relationship of these parameters to sea surface temperature (SST is found to assess sensitivity to change. It is shown that as SSTs increase near the coast, the frequency of hurricanes in these grids decrease significantly. This reinforces the importance of SST in areas of likely tropical cyclogenesis in determining the number of hurricanes near the coast, along with SSTs along the lifespan of the storm, rather than simply local SST. The range of hurricane wind speeds experienced near Florida is shown to increase with increasing SSTs (insignificant, suggesting that increased temperatures may allow hurricanes to maintain their strength as they pass over the Florida peninsula. The modifiable areal unit problem is assessed using multiple grid sizes. Moran's I and the local statistic G are calculated to examine spatial autocorrelation in the parameters. This research opens up future questions regarding rapid intensification and decay close to the coast and the relationship to changing SSTs.

  4. Hurricane risk variability along the Gulf of Mexico coastline.

    Science.gov (United States)

    Trepanier, Jill C; Ellis, Kelsey N; Tucker, Clay S

    2015-01-01

    Hurricane risk characteristics are examined across the U. S. Gulf of Mexico coastline using a hexagonal tessellation. Using an extreme value model, parameters are collected representing the rate or λ (frequency), the scale or σ (range), and the shape or ξ (intensity) of the extreme wind distribution. These latent parameters and the 30-year return level are visualized across the grid. The greatest 30-year return levels are located toward the center of the Gulf of Mexico, and for inland locations, along the borders of Louisiana, Mississippi, and Alabama. Using a geographically weighted regression model, the relationship of these parameters to sea surface temperature (SST) is found to assess sensitivity to change. It is shown that as SSTs increase near the coast, the frequency of hurricanes in these grids decrease significantly. This reinforces the importance of SST in areas of likely tropical cyclogenesis in determining the number of hurricanes near the coast, along with SSTs along the lifespan of the storm, rather than simply local SST. The range of hurricane wind speeds experienced near Florida is shown to increase with increasing SSTs (insignificant), suggesting that increased temperatures may allow hurricanes to maintain their strength as they pass over the Florida peninsula. The modifiable areal unit problem is assessed using multiple grid sizes. Moran's I and the local statistic G are calculated to examine spatial autocorrelation in the parameters. This research opens up future questions regarding rapid intensification and decay close to the coast and the relationship to changing SSTs.

  5. Hydrocarbon production cost functions in the Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, Mark J. [Center for Energy Studies, Louisiana State University, Energy Coast and Environment Building, Nicholson Extension Drive, Baton Rouge, LA 70803 (United States)

    2006-09-15

    Hydrocarbon production is the process of extracting oil and gas reserves from the earth, and then treating, processing, and transporting the oil and gas to market. Production costs are those costs required to operate and maintain wells and related equipment and facilities. Production costs are generally not available in commercial databases, however, and must be derived from survey instruments or extracted from company records. An alternative approach is to infer production cost based on an assessment of the economic limit of structures removed from service. The purpose of this paper is to derive generalized production cost functions of offshore structures in the Gulf of Mexico using the economic limit model. A statistical description of over 1700 offshore structures removed in the Gulf of Mexico over the past two decades is provided, followed by generalized regression models that infer production cost from gross revenue statistics at the time of abandonment. A description of the factors involved in the analysis and a summary of the results are presented. (author)

  6. Major depression and depressive symptoms in Australian Gulf War veterans 20 years after the Gulf War.

    Science.gov (United States)

    Ikin, J F; McKenzie, D P; Gwini, S M; Kelsall, H L; Creamer, M; McFarlane, A C; Clarke, D M; Wright, B; Sim, M

    2016-01-01

    Risk of major depression (depression) was elevated in Australia's Gulf War veterans in a 2000-2002 (baseline) study. A follow up study has measured the Gulf War-related risk factors for depression, also the current prevalence and severity of depression, use of anti-depressant medication, and persistence, remittance or incidence of depression since baseline in Gulf War veterans and a military comparison group. Participants completed the Composite International Diagnostic Interview v.2.1, the 9-item Patient Health Questionnaire and the Military Service Experience Questionnaire, and consented to Repatriation Pharmaceutical Benefits Scheme (RPBS) and PBS linkage. Prevalence of depression (9.7% Gulf War veterans and 7.7% comparison group; adj RR=1.2, 95% CI 0.8-1.7), and pattern of persistence, remittance and incidence of depression since baseline, were similar in the two groups, however veterans reported slightly more severe symptoms (adj median difference 1, 95% CI 0.26-1.74) and were more likely to have been dispensed anti-depressant medication (adj RR=1.56, 95% CI 1.05-2.32). Depression amongst veterans was associated with self-reported Gulf War-related stressors in a dose-response relationship (adj RR 1.06, 95% CI 1.02-1.09). Lower participation rates at follow up resulted in reduced statistical power compared with baseline, Gulf War related stressor data collected at baseline was at risk of recall bias, and RPBS and PBS databases do not capture all dispensed Nervous System medications. More than 20 years after the Gulf War, veterans are experiencing slightly more severe depressive symptoms than a military comparison group, and depression continues to be associated with Gulf War-related stressors. Copyright © 2015. Published by Elsevier B.V.

  7. Diagnosis of Physical and Biological Control over Phytoplankton in the Gulf of Maine-Georges Bank Region Using an Adjoint Data Assimilation Approach

    Institute of Scientific and Technical Information of China (English)

    WANG Caixia; Paola Malanotte-Rizzoli

    2014-01-01

    The linkage between physical and biological processes, particularly the effect of the circulation field on the distribution of phytoplankton, is studied by applying a two-dimensional model and an adjoint data assimilation approach to the Gulf of Maine-Georges Bank region. The model results, comparing well with observation data, reveal seasonal and geographic variations of phytoplankton concentration and verify that the seasonal cycles of phytoplankton are controlled by both biological sources and ad-vection processes which are functions of space and time and counterbalance each other. Although advective flux divergences have greater magnitudes on Georges Bank than in the coastal region of the western Gulf of Maine, advection control over phytoplankton concentration is more significant in the coastal region of the western Gulf of Maine. The model results also suggest that the two separated populations in the coastal regions of the western Gulf of Maine and on Georges Bank are self-sustaining.

  8. 78 FR 42021 - Atlantic Highly Migratory Species; Commercial Gulf of Mexico Aggregated Large Coastal Shark and...

    Science.gov (United States)

    2013-07-15

    ... Species; Commercial Gulf of Mexico Aggregated Large Coastal Shark and Gulf of Mexico Hammerhead Shark... management groups for aggregated large coastal sharks (LCS) and hammerhead sharks in the Gulf of Mexico...: The commercial Gulf of Mexico aggregated LCS and Gulf of Mexico hammerhead shark management groups...

  9. Faults in the Gulf Coast [gcfaultsg

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — These mapped faults are modified from Plate 2, Principal structural features, Gulf of Mexico Basin (compiled by T.E. Ewing and R.F. Lopez) in Volume J, The Geology...

  10. The Gulf Stream and Density of Fluids

    Science.gov (United States)

    Landstrom, Erich

    2006-01-01

    A few kilometers from the shores of Palm Beach County, Florida, is the Gulf Stream current--a remarkable "river" within an ocean. The current's journey across the Atlantic Ocean connects southeast Florida and southwest Great Britain as it streams steadily north at speeds of 97 km a day; moving 100 times as much water as all the rivers on Earth.…

  11. Multiple Currents in the Gulf Stream System

    OpenAIRE

    Fuglister, F. C.

    2011-01-01

    A new interpretation of the accumulated temperature and salinity data from the Gulf Stream Area indicates that the System is made up of a series of overlapping currents. These currents are separated by relatively weak countercurrents. Data from a recent survey are presented as supporting this hypothesis.DOI: 10.1111/j.2153-3490.1951.tb00804.x

  12. The Gulf Stream: Inertia and friction

    OpenAIRE

    ASSAF, GAD

    2011-01-01

    The inertial theory of the Gulf Stream (Charney, 1955) is extended to include vertical friction in the cyclonic shear zone (the western side) of the stream. The vertical friction is assumed to be controlled by local Froude conditions.DOI: 10.1111/j.2153-3490.1977.tb00717.x

  13. Fishery potential of the Gulf of Kachchh

    Digital Repository Service at National Institute of Oceanography (India)

    Nair, V.R.; Govindan, K.; Ramaiah, Neelam; Gajbhiye, S.N.

    /h) was three times more productive than the creek (av. 2.3 kg/h). The number of species found in the Gulf and creek were respectively 34 and 20 suggesting good biodiversity of the living resources of the area....

  14. Prospects for Gulf Region with closed greenhouse

    NARCIS (Netherlands)

    Campen, J.B.

    2009-01-01

    In countries such as Saudi Arabia and the United Arab Emirates, water is scarce as rainfall is minimal. Growers in the Gulf Region rely on groundwater for evaporative cooling and irrigation. This source of water is running out and growers are deciding to end production. The governments of the Kingdo

  15. Arab-Americans and the Gulf Crisis.

    Science.gov (United States)

    Noor Al-Deen, Hana S.

    A study examined the sentiment and impact of different types, channels, and forms of aggression against the Arab-American community during the Gulf Crisis. Data were selected from entries in the 1990 Anti-Arab Discrimination and Hate Crimes Log of the American-Arab Anti-Discrimination (ADC) National Office. Results show that there were 129 acts of…

  16. Fish larvae from the Gulf of California

    Directory of Open Access Journals (Sweden)

    Gerardo Aceves-Medina

    2003-03-01

    Full Text Available Taxonomic composition of fish larvae was analysed from 464 plankton samples obtained during 10 oceanographic surveys in the Gulf of California between 1984 and 1988. We identified 283 taxa: 173 species, 57 genera, and 53 families. Tropical and subtropical species predominated except during the winter, when temperate-subarctic species were dominant. The most abundant species were the mesopelagic Benthosema panamense, Triphoturus mexicanus and Vinciguerria lucetia, but the coastal pelagic species Engraulis mordax, Opisthonema spp., Sardinops caeruleus and Scomber japonicus were also prominent. The taxonomic composition of the ichthyoplankton shows the seasonality of the Gulf as well as environmental changes that occurred between the 1984-1987 warm period and the 1956-1957 cool period previously reported. The presence of E. mordax larvae as one of the most abundant species in the Gulf provides evidence of the reproduction of this species two years before the development of the northern anchovy fishery and the decline of the sardine fishery in the Gulf of California.

  17. New offshore platform in the Mexican Gulf

    Energy Technology Data Exchange (ETDEWEB)

    Beisel, T.

    1982-04-01

    After a construction period of only 10 months, the second steel Offshore platform was recently completed in the Mexican Gulf. The pattern for this structure was the Cognac platform. The erection of the new platform, called the 'Cerveza' platform, is described in the article.

  18. Fault Zones in the Gulf Coast [gcfltzoneg

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — These data represent major fault zones as indicated on Plate 2, Principal structural features, Gulf of Mexico Basin (compiled by T.E. Ewing and R.F. Lopez) in volume...

  19. Salt Diapirs in the Gulf Coast [gcdiapirg

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Locations and shapes of salt diapirs were modified after the New Orleans Geological Society map, Salt tectonism of the U.S. Gulf Coast Basin (compiled by J.A. Lopez,...

  20. Marine and brackish-water molluscan biodiversity in the Gulf of California, Mexico

    Directory of Open Access Journals (Sweden)

    Michel E. Hendrickx

    2007-12-01

    Full Text Available A database containing taxonomic, distributional and ecological data of 2194 species of marine molluscs (1528 Gastropoda, 565 Bivalvia, 59 Polyplacophora, 21 Scaphopoda, 20 Cephalopoda, and one Monoplacophora known to the Gulf of California, Mexico, was used to analyse their latitudinal and bathymetric distribution, to define their substrate preferences, and to elaborate a biodiversity model for the study area. The model was based on a comparison between the set of data associated with each species (i.e., depth range, associated substrates and geographic distribution within the Gulf and the environmental conditions prevailing in the Gulf (i.e., depth and substrate, using a georeferenced grid of 2 x 2 nautical miles. Results are presented as predictive biodiversity distribution maps for the major molluscan groups. Putative biodiversity ranges were defined using a percentage accumulative system with 20% classes. As expected, the highest biodiversity occurs along the coastline and around the islands. A south-north biodiversity gradient is observed, although it is less evident between the southern and central Gulf.

  1. Regional Geophysical Surveys and Crustal Structure of the Gulf of Mexico

    Science.gov (United States)

    Rodríguez-Chavez, F.; Fucugauchi, J. U.

    2007-05-01

    Results of processing and modeling of anomaly data from regional geophysical surveys in the southern sector of the Gulf of Mexico are presented. The Gulf of Mexico has been intensively studied for several years, mainly because of the economic potential of the oil and gas resources. The basin may have formed by sea-floor spreading, rifting and lateral translation/rotation of continental slivers ssociated with major break-up and drifting apart of North and South America continental plates in the mid Mesozoic. Major structural features and crustal structure, including the continent-ocean transition and Gulf coastal passive margin are relatively poorly understood. Aerogeophysical gravity and magnetic surveys have been conducted and data are processed and modeled to investigate on the Gulf crustal structure. Spectral statistical estimates of regional basement depths derived from aeromagnetics give mean depths of 8000 m. Estimates derived from gravity anomalies are in the order of 10000 m. Depths derived from 2D and 3D seismic reflection surveys conducted for oil exploration purposes in selected areas indicate average depths to basement from 6000 m to values grater than those derived from potential field data.

  2. D Recording of Underwater Antiquities in the South Euboean Gulf

    Science.gov (United States)

    Diamanti, E.; Vlachaki, F.

    2015-04-01

    An underwater archaeological survey was initiated in 2006 by the Hellenic Institute of Marine Archaeology in collaboration with the Ephorate of Underwater Antiquities of Greece, in the South Euboean Gulf. The survey is being conducted under the direction of the archaeologist Dr G. Koutsouflakis and in the course of the project important shipwrecks of Classical, Roman, and Byzantine periods have been brought to light, adding tangible evidence on ancient seafaring and maritime trade. The South Euboean Gulf archaeological survey has presented many challenges to the documentation team of H.I.M.A, and has served as a case-study for 3D recording applied on ancient wrecks, found at medium depths (22-47m) and under the conditions that are imposed during an archaeological survey of a certain geographical region. This paper focuses on the implementation of photogrammetric and geodetic techniques used for acquisition and processing of collected data, in order to generate 3D models for six different wrecks, resulting in a fast, reliable and cost efficient method to record underwater archaeological sites.

  3. Morphotectonics of Kid drainage basin, Southeastern Sinai: A landscape evolution coeval to Gulf of Aqaba - Dead Sea rifting

    Science.gov (United States)

    Shalaby, Ahmed; Shawky, Mohamed

    2014-12-01

    The Pleistocene fluvio-tectonic conditions have shaped the landscapes of Sinai Peninsula through development of small sedimentary traps following preexisting lineaments. In the Gulf of Aqaba region, orientation of these lineaments with respect to the Pleistocene stress field develops strike-slip simple and dip-slip pure extensional shear models that induced rifting of the Gulf of Aqaba - Dead Sea fault system. The Beida and Nabq grabens are two major rift-related depressions at the southwestern coast of the Gulf of Aqaba region. Both grabens are landscapes that received alluvial sediments of the Kid drainage basin (KDB), which is one of the largest drainage systems in the western region of the Gulf of Aqaba fault-scarp. The Beida graben is formed at a horse tail structure next to Abiad and Kid faults, while the Nabq graben is a pull-apart structure formed as onshore continuation of the Dakar deep. The geometry and origin of these landscapes are the intrinsic themes of this study to investigate the morphotectonic evolution of the KDB terrain within the tectonic framework of the Gulf of Aqaba - Dead Sea rift. The hanging terraces and canyons being at higher elevations on the Gulf of Aqaba fault-scarp; and the accumulation of younger alluvial fans, talus cones and bajada on its footslope indicate that the KDB landscape is basically shaped; and evolutionary modified by hinterland uplifting of the Gulf of Aqaba region. Hence, two morphotectonic evolution periods of the KDB terrain coincide with the early NE- and late NNE-trending extensional Pleistocene axes. The early period started with deposition of the older alluvial fan sediments that emerged at the outlet of KDB, and partially buried the Gulf of Aqaba fault-scarp. Subsequent hinterland uplifting revived the Gulf of Aqaba fault-scarp with development of hanging alluvial and bed-rock terraces; and the older alluvial fan sediments are uplifted on the footwall of southward-dipping normal faults whose hanging

  4. Rationale, design, methodology and hospital characteristics of the first gulf acute heart failure registry (gulf care

    Directory of Open Access Journals (Sweden)

    Kadhim J Sulaiman

    2014-01-01

    Full Text Available Background: There is paucity of data on heart failure (HF in the Gulf Middle East. The present paper describes the rationale, design, methodology and hospital characteristics of the first Gulf acute heart failure registry (Gulf CARE. Materials and Methods: Gulf CARE is a prospective, multicenter, multinational registry of patients >18 year of age admitted with diagnosis of acute HF (AHF. The data collected included demographics, clinical characteristics, etiology, precipitating factors, management and outcomes of patients admitted with AHF. In addition, data about hospital readmission rates, procedures and mortality at 3 months and 1-year follow-up were recorded. Hospital characteristics and care provider details were collected. Data were entered in a dedicated website using an electronic case record form. Results: A total of 5005 consecutive patients were enrolled from February 14, 2012 to November 13, 2012. Forty-seven hospitals in 7 Gulf States (Oman, Saudi Arabia, Yemen, Kuwait, United Gulf Emirates, Qatar and Bahrain participated in the project. The majority of hospitals were community hospitals (46%; 22/47 followed by non-University teaching (32%; 15/47 and University hospitals (17%. Most of the hospitals had intensive or coronary care unit facilities (93%; 44/47 with 59% (28/47 having catheterization laboratory facilities. However, only 29% (14/47 had a dedicated HF clinic facility. Most patients (71% were cared for by a cardiologist. Conclusions: Gulf CARE is the first prospective registry of AHF in the Middle East, intending to provide a unique insight into the demographics, etiology, management and outcomes of AHF in the Middle East. HF management in the Middle East is predominantly provided by cardiologists. The data obtained from this registry will help the local clinicians to identify the deficiencies in HF management as well as provide a platform to implement evidence based preventive and treatment strategies to reduce the burden

  5. Transport and Vertical Distribution of Urban Pollutants over the Guinean Gulf

    Science.gov (United States)

    Deroubaix, Adrien; Flamant, Cyrille; Menut, Laurent

    2017-04-01

    In the countries of the Guinean Gulf, the population has been growing rapidly during the last decades. The sustained economic growth is associated with increased emissions from traffic, industries, and households, and with high pollution levels. Particulate matter (PM10) emissions from urbanized areas are analyzed in the Guinean gulf coastal region by both models (WRF and CHIMERE) and observations during the beginning of the monsoon from May to July. From the Guinean gulf coast to the Sahel, the urban PM10 concentrations are highest in June, and they display frequent northward transport events. These urban pollution transport events occurred over the entire Guinean Gulf coastal region with a zonal gradient of low concentration in Abidjan to high concentration in Lagos. The main drivers are the absence of precipitation and low wind associated with the low boundary layer height. The major part of the urban pollution is transported at night in the surface layer (3 m/s), but a significant part of the pollution is caught by the low level jet and transported rapidly (15 m/s). All these results highlight specific atmospheric conditions leading to high urban pollution events along the coast and to pollution transport reaching the Sahel, which may severely impact human health.

  6. Diversity and distribution of winter phytoplankton in the Arabian Gulf and the Sea of Oman

    Science.gov (United States)

    Polikarpov, Igor; Saburova, Maria; Al-Yamani, Faiza

    2016-05-01

    The spatial distribution of the phytoplankton (diversity, composition, and cell abundance) was described in relation to local environmental conditions across the Arabian Gulf, the Strait of Hormuz, and the Sea of Oman based on data of ROPME cruise of winter 2006. The 376 phytoplankton taxa identified in these waters represented a diverse composition of species with a prevalence of dinoflagellates and diatoms. Three peaks in the phytoplankton abundance were recorded throughout the studied area associated with diatom-dominated phytoplankton blooms in the central and northwestern part of the Arabian Gulf and in the Sea of Oman and the adjacent waters. The studied area was divided into three main regions by cluster analysis based on differences in the phytoplankton composition and concentration. The Sea of Oman and the Strait of Hormuz were occupied by highly abundant, strongly diatom-dominated phytoplankton assemblage. The Arabian Gulf was divided into two main regions along a diagonal northwest-southeast axis, with rather diatom-dominated phytoplankton assemblage off the south and along the Iranian coast but with flagellate-dominated phytoplankton of the north and along the Arabian coast. The distance-based linear modeling revealed a significant relationship between the phytoplankton composition and water masses as indexed by salinity. Our results demonstrated that abundance and composition of winter phytoplankton were related to water circulation pattern in the Arabian Gulf and the Sea of Oman.

  7. Impacts from oil and gas produced water discharges on the gulf of Mexico hypoxic zone.

    Energy Technology Data Exchange (ETDEWEB)

    Parker, M. E.; Satterlee, K.; Veil, J. A.; Environmental Science Division; ExxonMobil Production Co.; Shell Offshore

    2006-01-01

    Shallow water areas of the Gulf of Mexico continental shelf experience low dissolved oxygen (hypoxia) each summer. The hypoxic zone is primarily caused by input of nutrients from the Mississippi and Atchafalaya Rivers. The nutrients stimulate the growth of phytoplankton, which leads to reduction of the oxygen concentration near the sea floor. During the renewal of an offshore discharge permit used by the oil and gas industry in the Gulf of Mexico, the U.S. Environmental Protection Agency (EPA) identified the need to assess the potential contribution from produced water discharges to the occurrence of hypoxia. The EPA permit required either that all platforms in the hypoxic zone submit produced water samples, or that industry perform a coordinated sampling program. This paper, based on a report submitted to EPA in August 2005 (1), describes the results of the joint industry sampling program and the use of those results to quantify the relative significance of produced water discharges in the context of other sources on the occurrence of hypoxia in the Gulf of Mexico. In the sampling program, 16 facilities were selected for multiple sampling - three times each at one month intervals-- and another 34 sites for onetime sampling. The goal of the sampling program was to quantify the sources and amount of oxygen demand associated with a variety of Gulf of Mexico produced waters. Data collected included direct oxygen demand measured by BOD5 (5-day biochemical oxygen demand) and TOC (total organic carbon) and indirect oxygen demand measured by nitrogen compounds (ammonia, nitrate, nitrate, and TKN [total Kjeldahl nitrogen]) and phosphorus (total phosphorus and orthophosphate). These data will serve as inputs to several available computer models currently in use for forecasting the occurrence of hypoxia in the Gulf of Mexico. The output of each model will be compared for consistency in their predictions and then a semi-quantitative estimate of the relative significance of

  8. Late glacial to Holocene water level and climate changes in the Gulf of Gemlik, Sea of Marmara: evidence from multi-proxy data

    Science.gov (United States)

    Filikci, Betül; Eriş, Kürşad Kadir; Çağatay, Namık; Sabuncu, Asen; Polonia, Alina

    2017-02-01

    Multi-proxy analyses of new piston core M13-08 together with seismic data from the Gulf of Gemlik provide a detailed record of paleoceanographic and paleoclimatic changes with special emphasis on the timing of the connections between the Sea of Marmara (SoM) and the Gulf of Gemlik during the late Pleistocene to Holocene. The deposition of a subaqueous delta sourced from the Armutlu River to the north is attributed to the lowstand lake level at -60 m in the gulf prior to 13.5 cal ka BP. On the basis of the seismic data, it is argued that the higher lake level (-60 m) in the gulf compared to the SoM level (-85 m) attests to its disconnection from the SoM during the late glacial period. Ponto-Caspian assemblages in the lacustrine sedimentary unit covering the time period between 13.5 and 12 cal ka BP represent a relict that was introduced into the gulf by a Black Sea outflow during the marine isotope stage 3 interstadial. Contrary to the findings of previous studies, the data suggest that such an outflow into the Gulf of Gemlik during the late glacial period could have occurred only if the SoM lake level (-85 m) was shallower than the sill depth (-55 m) of the gulf in the west. A robust age model of the core indicates the connection of the gulf with the marine SoM at 12 cal ka BP, consistent with the sill depth (-55 m) of the gulf on the global sea level curve. Strong evidence of a marine incursion into the gulf is well documented by the μ-XRF Sr/Ca data. The available profiles of elemental ratios in core M13-08, together with the age-depth model, imply that a warm and wet climate prevailed in the gulf during the early Holocene (12-10.1 cal ka BP), whereas the longest drought occurred during the middle Holocene (8.2-5.4 cal ka BP). The base of the main Holocene sapropel in the gulf is dated at 10.1 cal ka BP, i.e., 500 years younger than its equivalent in the SoM. The late Holocene is earmarked by warm and wet climate periods (5.0-4.2 and 4.2-2.7 cal ka BP) with some

  9. Late glacial to Holocene water level and climate changes in the Gulf of Gemlik, Sea of Marmara: evidence from multi-proxy data

    Science.gov (United States)

    Filikci, Betül; Eriş, Kürşad Kadir; Çağatay, Namık; Sabuncu, Asen; Polonia, Alina

    2017-10-01

    Multi-proxy analyses of new piston core M13-08 together with seismic data from the Gulf of Gemlik provide a detailed record of paleoceanographic and paleoclimatic changes with special emphasis on the timing of the connections between the Sea of Marmara (SoM) and the Gulf of Gemlik during the late Pleistocene to Holocene. The deposition of a subaqueous delta sourced from the Armutlu River to the north is attributed to the lowstand lake level at -60 m in the gulf prior to 13.5 cal ka BP. On the basis of the seismic data, it is argued that the higher lake level (-60 m) in the gulf compared to the SoM level (-85 m) attests to its disconnection from the SoM during the late glacial period. Ponto-Caspian assemblages in the lacustrine sedimentary unit covering the time period between 13.5 and 12 cal ka BP represent a relict that was introduced into the gulf by a Black Sea outflow during the marine isotope stage 3 interstadial. Contrary to the findings of previous studies, the data suggest that such an outflow into the Gulf of Gemlik during the late glacial period could have occurred only if the SoM lake level (-85 m) was shallower than the sill depth (-55 m) of the gulf in the west. A robust age model of the core indicates the connection of the gulf with the marine SoM at 12 cal ka BP, consistent with the sill depth (-55 m) of the gulf on the global sea level curve. Strong evidence of a marine incursion into the gulf is well documented by the μ-XRF Sr/Ca data. The available profiles of elemental ratios in core M13-08, together with the age-depth model, imply that a warm and wet climate prevailed in the gulf during the early Holocene (12-10.1 cal ka BP), whereas the longest drought occurred during the middle Holocene (8.2-5.4 cal ka BP). The base of the main Holocene sapropel in the gulf is dated at 10.1 cal ka BP, i.e., 500 years younger than its equivalent in the SoM. The late Holocene is earmarked by warm and wet climate periods (5.0-4.2 and 4.2-2.7 cal ka BP) with some

  10. Change point detection of the Persian Gulf sea surface temperature

    Science.gov (United States)

    Shirvani, A.

    2017-01-01

    In this study, the Student's t parametric and Mann-Whitney nonparametric change point models (CPMs) were applied to detect change point in the annual Persian Gulf sea surface temperature anomalies (PGSSTA) time series for the period 1951-2013. The PGSSTA time series, which were serially correlated, were transformed to produce an uncorrelated pre-whitened time series. The pre-whitened PGSSTA time series were utilized as the input file of change point models. Both the applied parametric and nonparametric CPMs estimated the change point in the PGSSTA in 1992. The PGSSTA follow the normal distribution up to 1992 and thereafter, but with a different mean value after year 1992. The estimated slope of linear trend in PGSSTA time series for the period 1951-1992 was negative; however, that was positive after the detected change point. Unlike the PGSSTA, the applied CPMs suggested no change point in the Niño3.4SSTA time series.

  11. No evidence for altered cellular immune functions in personnel deployed in the Persian Gulf during and after the Gulf War--The Danish Gulf War study

    DEFF Research Database (Denmark)

    Bregenholt, S; Ishøy, T; Skovgaard, L T;

    2001-01-01

    Veterans who have participated in the Gulf War suffer from a number of symptoms, collectively referred to as the Gulf War Syndrome. It has been hypothesized that a change in the systemic cytokine balance or other changes in immunological parameters could be responsible for some of the symptoms. We...

  12. 77 FR 39998 - Gulf of Mexico Fishery Management Council; Public Meeting

    Science.gov (United States)

    2012-07-06

    ...The Gulf of Mexico Fishery Management Council (Council) will convene its Law Enforcement Advisory Panel (LEAP) in conjunction with the Gulf States Marine Fisheries Commission's Law Enforcement Committee...

  13. Mercury in the Gulf of Mexico: sources to receptors.

    Science.gov (United States)

    Harris, Reed; Pollman, Curtis; Landing, William; Evans, David; Axelrad, Donald; Hutchinson, David; Morey, Steven L; Rumbold, Darren; Dukhovskoy, Dmitry; Adams, Douglas H; Vijayaraghavan, Krish; Holmes, Christopher; Atkinson, R Dwight; Myers, Tom; Sunderland, Elsie

    2012-11-01

    Gulf of Mexico (Gulf) fisheries account for 41% of the U.S. marine recreational fish catch and 16% of the nation's marine commercial fish landings. Mercury (Hg) concentrations are elevated in some fish species in the Gulf, including king mackerel, sharks, and tilefish. All five Gulf states have fish consumption advisories based on Hg. Per-capita fish consumption in the Gulf region is elevated compared to the U.S. national average, and recreational fishers in the region have a potential for greater MeHg exposure due to higher levels of fish consumption. Atmospheric wet Hg deposition is estimated to be higher in the Gulf region compared to most other areas in the U.S., but the largest source of Hg to the Gulf as a whole is the Atlantic Ocean (>90%) via large flows associated with the Loop Current. Redistribution of atmospheric, Atlantic and terrestrial Hg inputs to the Gulf occurs via large scale water circulation patterns, and further work is needed to refine estimates of the relative importance of these Hg sources in terms of contributing to fish Hg levels in different regions of the Gulf. Measurements are needed to better quantify external loads, in-situ concentrations, and fluxes of total Hg and methylmercury in the water column, sediments, and food web.

  14. The Gulf Stream pathway and the impacts of the eddy-driven abyssal circulation and the Deep Western Boundary Current

    Science.gov (United States)

    Hurlburt, Harley E.; Hogan, Patrick J.

    2008-08-01

    A hydrodynamic model of the subtropical Atlantic basin and the Intra-Americas Sea (9-47°N) is used to investigate the dynamics of Gulf Stream separation from the western boundary at Cape Hatteras and its mean pathway to the Grand Banks. The model has five isopycnal Lagrangian layers in the vertical and allows realistic boundary geometry, bathymetry, wind forcing, and a meridional overturning circulation (MOC), the latter specified via ports in the northern and southern boundaries. The northward upper ocean branch of the MOC (14 Sv) was always included but the southward Deep Western Boundary Current (DWBC) was excluded in some simulations, allowing investigation of the impacts of the DWBC and the eddy-driven mean abyssal circulation on Gulf Stream separation from the western boundary. The result is resolution dependent with the DWBC playing a crucial role in Gulf Stream separation at 1/16° resolution but with the eddy-driven abyssal circulation alone sufficient to obtain accurate separation at 1/32° resolution and a realistic pathway from Cape Hatteras to the Grand Banks with minimal DWBC impact except southeast of the Grand Banks. The separation from the western boundary is particularly sensitive to the strength of the eddy-driven abyssal circulation. Farther to the east, between 68°W and the Grand Banks, all of the 1/16° and 1/32° simulations with realistic topography (with or without a DWBC) gave similar generally realistic mean pathways with clear impacts of the topographically constrained eddy-driven abyssal circulation versus very unrealistic Gulf Stream pathways between Cape Hatteras and the Grand Banks from otherwise identical simulations run with a flat bottom, in reduced-gravity mode, or with 1/8° resolution and realistic topography. The model is realistic enough to allow detailed model-data comparisons and a detailed investigation of Gulf Stream dynamics. The corresponding linear solution with a Sverdrup interior and Munk viscous western boundary

  15. Probiotic (VSL#3) for Gulf War Illness

    Science.gov (United States)

    2012-10-01

    are relevant to GW Veterans. Altered gut flora may be the etiological factor for IBS and GW Illness. Probiotics are living organisms that improve... health by re-establishing a normal gut flora. The overall objective of the study was to determine whether Bifidobacterium infantis 35624 (Align...W81XWH-10-1-0593 TITLE: Probiotic (VSL#3) for Gulf War Illness. PRINCIPAL INVESTIGATOR: Ashok Tuteja, M.D. M.P.H

  16. Gulf of Mexico mud toxicity limitations

    Energy Technology Data Exchange (ETDEWEB)

    Dunn, H.E.; Beardmore, D.H. (Phillips Petroleum Co., Bartlesville, OK (USA)); Stewart, W.S. (Drilling Specialties Co. (US))

    1989-10-01

    Because of the Environmental Protection Agency's recent toxicity limits on drilling mud discharges for offshore Gulf of Mexico, Phillips Petroleum conducted a mud toxicity study based on both field and lab tests. The study, discussed in this article, found the polyanionic cellulose-sulfomethylated quebracho-chrome lignosulfonate mud Phillips had been using would comfortably pass the toxicity limitations. The study also found barite and thinners were of low toxicity, and hydrocarbons and surfactants were highly toxic.

  17. Florida, Bahamas, Cuba and Gulf Stream, USA

    Science.gov (United States)

    1992-01-01

    This unique photo offers a view of the Florida peninsula, western Bahamas, north central Cuba and the deep blue waters of the Gulf Stream, that hugs the east coast of Florida (27.0N, 82.0W). In addition to being an excellent photograph for showing the geographical relationships between the variety of landforms in this scene, the typical effect of the land-sea breeze is very much in evidence as few clouds over water, cumulus build up over landmass.

  18. The Gulf: A young sea in decline

    OpenAIRE

    Sheppard, Charles (Charles R. C.); Al-Husiani, Mohsen; Al-Jamali, F.; Al-yamani, Faiza; Baldwin, Rob; Bishop, James; Benzoni, Francesca; Dutrieux, Eric; Dulvy, Nicholas K.; Durvasulah, Subba Rao V.; Jonesi, David A.; Loughland, Ron; Mediok, David; Nithyanandan, M.; Pilling, Graham M.

    2009-01-01

    This review examines the substantial changes that have taken place in marine habitats and resources of the Gulf over the past decade. The habitats are especially interesting because of the naturally high levels of temperature and salinity stress they experience, which is important in a changing world climate. However, the extent of all natural habitats is changing and their condition deteriorating because of the rapid development of the region and, in some cases from severe, episodic warming ...

  19. Q&A on Beibu Gulf

    Institute of Scientific and Technical Information of China (English)

    Alice

    2010-01-01

    China-ASEAN FTA, the world's largest free trade area in terms of population took effect on January 1, 2010, covering 13 million square kilometers and 1.9 billion people. Over 90 percent of the commodities traded between China and the six original ASEAN countries, including Brunei, Indonesia, Malaysia, the Philippines, Singapore and Thailand, now enjoy no tariffs from 2010. As a window to ASEAN countries, Beibu Gulf Economic Zone is in more limelight since the new year.

  20. Probiotic (VSL 3) for Gulf War Illness

    Science.gov (United States)

    2016-10-01

    ongoing to recruit more Gulf War veterans. The first set of stool samples have been sent to Lawrence Berkeley Laboratory for microbiota analysis. 15...scientific evidence that probiotics by restoring normal gut flora improve symptoms of IBS. Probiotics have also been shown to improve arthritis and...affecting the study assessment.  The first set of stool samples have been sent to the Lawrence Berkeley laboratory for microbiota analysis.  We have

  1. Sediment Sources in the Persian Gulf

    Science.gov (United States)

    Mahoutian, Mehrab

    2014-05-01

    Sediment Constituent Analysis is an effective tool for identifying sediment sources. Based on several sediment samples taken from different sites all over the Iranian coastlines, we have been able to show that an important portion of sediment on the beaches in the Persian Gulf is bio-clastic; that is, biologically created from the coral environment as well as other marine habitats. Unlike mineral (clastic) sediments, carbonate sediments are born not made. Furthermore, carbonate sand constituents are generally less durable than their quartz and mineral counterparts, and break down relatively quickly. Therefore, destruction of reefs and degradation of marine habitat are certain to reduce the sand supply to the shoreline in the Persian Gulf that is necessary to maintain beaches. Carbonate sands are also found on the coastline of the Oman Sea. One of the striking things about the sediments along the coastline of Iran is the high percentage of carbonate material. Molluscan debris is common, even ubiquitous. This reflects the populations living in the offshore waters. Some molluscs thrive in high-energy sandy environments, others like finer sediments. Some live at the surface, while some burrow down as much as a half-metre. A great deal of information can be gained from the study of the species of mollusk and their distribution in the sediments. This paper introduces a few case studies done in different parts of the Persian Gulf by using this method as a general assessment toolbox.

  2. Status of hepatocellular carcinoma in Gulf region.

    Science.gov (United States)

    Rasul, Kakil Ibrahim; Al-Azawi, Safaa H; Chandra, Prem; Abou-Alfa, Ghassan K; Knuth, Alexander

    2013-12-01

    Hepatocellular carcinoma (HCC) has a unique geographic distribution that is likely to be determined by specific etiologic factors. There is a distinctive difference in sex and age related occurrence of disease. In the Gulf region, there are contradicting data on the prevalence and death rates due to HCC. In this review we highlight some aspects of HCC specific to the Gulf region. A retrospective analysis of 150 patient's data is presented, including demographic, epidemiological, aetiological disease status assessment with child Pugh criteria, modes of treatment and treatment related outcome. Hepatitis C virus (HCV) infection was the most common (45%) documented etiology, similar to Western European countries, followed by hepatitis B virus (HBV) infection in 27% of cases, alcoholic liver disease only in six patients (4%). Child-Pugh assessment was A in 33%, B in 37% and C in 30% of observed patients. Surgery (liver resection or transplantation) was performed in 12% and local ablation in 5% of cases. The others were treated by chemo-embolization in 17% and by systemic therapy with sorafenib in 13% of patients. Nearly half of the patients (53%) were in advanced stages and received palliative treatment. To improve the outcome of treatment in HCC patients in the Gulf region, an effective and strategic screening program must be implemented for early diagnosis and treatment to improve the outcome of this mostly fatal disease.

  3. An integrated systems framework for service vessel forecasting in the Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, Mark J. [Center for Energy Studies, Louisiana State University, Energy Coast and Environment Building, Nicholson Extension Drive, Baton Rouge, LA 70803 (United States)

    2010-07-15

    Throughout the world wherever oil and gas is discovered, a support industry will develop and evolve with the needs of industry and government regulation. In the Gulf of Mexico, a large variety of marine vessels transport goods and provide services to exploration, development and production activity, and play an important role in the economic and ecological impacts across communities. The spatial and temporal dynamics of the logistics network is complex and dynamic and closely related to the magnitude, duration, type, and sequence of offshore workflows and activities. The purpose of this paper is to develop a methodological framework to quantify the number of offshore supply vessel and crew boat departures by activity across the Gulf's coastal regions in support of the oil and gas industry. The logistics network is modeled as a linear time-invariant deterministic system and implemented using an input-output model. We provide a methodological framework to quantify the magnitude and distribution of service vessel trips to forecast port activity. This is the first integrated modeling study on service vessel trips in the Gulf of Mexico and special attention is paid to the analytic framework, model assumptions, and limitations of the analysis. Generic examples illustrate the model implementation. (author)

  4. Strong eddy compensation for the Gulf Stream heat transport

    Science.gov (United States)

    Saenko, Oleg A.

    2015-12-01

    Using a high-resolution ocean model forced with high-resolution atmospheric fields, a 5 year mean heat budget of the upper ocean in the Gulf Stream (GS) region is analyzed. The heat brought to the region with the mean flows along the GS path is 2-3 times larger than the heat loss to the atmosphere, with the difference being balanced by a strong cooling effect due to lateral eddy heat fluxes. However, over a broad area off the Grand Banks, the eddies warm the uppermost ocean layers, partly compensating for the loss of heat to the atmosphere. The upward eddy heat flux, which brings heat from the deeper ocean to the upper layers, is 30-80% of the surface heat loss.

  5. Physical characterization of core samples recovered from Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Tae Sup; Carlos Santamarina, J. [School of Civil and Environmental Engineering, Georgia Institute of Technology, 790 Atlantic Drive, Atlanta, GA 30332-0355 (United States); Narsilio, Guillermo A. [Department of Civil and Environmental Engineering, The University of Melbourne, Engineering Block D 321, Parkville, VIC 3010 (Australia)

    2006-12-15

    Seventy whole rounds from conventional cores obtained during drilling to 300mbsf at Atwater Valley and Keathley Canyon in the Gulf of Mexico in April and May 2005 were tested to determine geophysical and geomechanical parameters (liquid and plastic limit, porosity, specific surface, pH, sediment electrical conductivity, P- and S-wave velocities and undrained shear strength). Available data from a pressure core are included as well. Results show that the sediments are high specific surface plastic clays, and exhibit pronounced time-dependent stiffness recovery. Strains during coring disturb specimens, yet, the water content retains the effective stress history and permits gaining stiffness and strength information from conventional cores. Remolding is exacerbated when gas expands upon decompression; the limited pressure core data available show the advantages of preserving the pore fluid pressure during core recovery and testing. Valuable parameters for sediment characterization and engineering analysis are extracted from the data using pre-existing soil models. (author)

  6. Submesoscale structures related to upwelling events in the Gulf of Finland, Baltic Sea (numerical experiments)

    Science.gov (United States)

    Väli, Germo; Zhurbas, Victor; Lips, Urmas; Laanemets, Jaan

    2017-07-01

    The appearance of submesoscale structures in the Gulf of Finland was investigated using model simulations for series of coastal upwelling events in July-September 2006. We applied the Princeton Ocean Model. The horizontal step of the model grid was refined to 0.5, 0.25 and 0.125 nautical miles in the gulf and reached 4 times the resolution in the rest of the Baltic Sea; there were 60 σ-levels in the vertical direction for all simulations. The contribution of salinity to the strength of baroclinic front of upwelling along the northern and southern coasts and thereby to the submesoscale dynamics of the gulf's surface layer was analyzed. Model results with refinement of the grid size to 0.125 nautical miles revealed different forms of submesoscale structures in the gulf's surface layer such as the high Rossby number (Ro) threads (elongated spots of Ro > 1 with typical width and length of 2-3 km and 10-50 km, respectively), cyclonic vortices with Ro > 1 core of 4-6 km diameter, and spiral cyclonic eddies (spirally wrapped high Rossby number threads) of 10-15 km diameter. The high potential vorticity threads presumably formed during the development phase, while the cyclonic vortices and spiral cyclonic eddies during the relaxation phase of upwelling. One of the simulated submesoscale cyclonic eddies, at the beginning with the Ro > 1 core extension as deep as 31-66 m was traced for the period of 33 days. The power spectral density of temperature and velocity fluctuations in the surface layer pointed at some increase of spectral levels and shallowing of spectral slopes towards - 2 on the shorter (submesoscale) wavelengths with the refinement of model grid.

  7. The influence of extreme winds on coastal oceanography and its implications for coral population connectivity in the southern Arabian Gulf.

    Science.gov (United States)

    Cavalcante, Geórgenes H; Feary, David A; Burt, John A

    2016-04-30

    Using long-term oceanographic surveys and a 3-D hydrodynamic model we show that localized peak winds (known as shamals) cause fluctuation in water current speed and direction, and substantial oscillations in sea-bottom salinity and temperature in the southern Persian/Arabian Gulf. Results also demonstrate that short-term shamal winds have substantial impacts on oceanographic processes along the southern Persian/Arabian Gulf coastline, resulting in formation of large-scale (52 km diameter) eddies extending from the coast of the United Arab Emirates (UAE) to areas near the off-shore islands of Iran. Such eddies likely play an important role in transporting larvae from well-developed reefs of the off-shore islands to the degraded reef systems of the southern Persian/Arabian Gulf, potentially maintaining genetic and ecological connectivity of these geographically distant populations and enabling enhanced recovery of degraded coral communities in the UAE.

  8. Hypoxia in the Northern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Dale, Virginia H [ORNL

    2010-01-01

    Since 1985, scientists have been documenting a hypoxic zone in the Gulf of Mexico each year. The hypoxic zone, an area of low dissolved oxygen that cannot support marine life, generally manifests itself in the spring. Since marine species either die or flee the hypoxic zone, the spread of hypoxia reduces the available habitat for marine species, which are important for the ecosystem as well as commercial and recreational fishing in the Gulf. Since 2001, the hypoxic zone has averaged 16,500 km{sup 2} during its peak summer months, an area slightly larger than the state of Connecticut, and ranged from a low of 8,500 km{sup 2} to a high of 22,000 km{sup 2}. To address the hypoxia problem, the Mississippi River/Gulf of Mexico Watershed Nutrient Task Force (or Task Force) was formed to bring together representatives from federal agencies, states, and tribes to consider options for responding to hypoxia. The Task Force asked the White House Office of Science and Technology Policy to conduct a scientific assessment of the causes and consequences of Gulf hypoxia through its Committee on Environment and Natural Resources (CENR). In 2000 the CENR completed An Integrated Assessment: Hypoxia in the Northern Gulf of Mexico (or Integrated Assessment), which formed the scientific basis for the Task Force's Action Plan for Reducing, Mitigating, and Controlling Hypoxia in the Northern Gulf of Mexico (Action Plan, 2001). In its Action Plan, the Task Force pledged to implement ten management actions and to assess progress every 5 years. This reassessment would address the nutrient load reductions achieved, the responses of the hypoxic zone and associated water quality and habitat conditions, and economic and social effects. The Task Force began its reassessment in 2005. In 2006 as part of the reassessment, USEPA's Office of Water, on behalf of the Task Force, requested that the U.S. Environmental Protection Agency (USEPA) Science Advisory Board (SAB) convene an independent

  9. Assessment of seismic hazards along the northern Gulf of Aqaba

    Science.gov (United States)

    Abueladas, Abdel-Rahman Aqel

    Aqaba and Elat are very important port and recreation cities for the Hashemite Kingdom of Jordan and Israel, respectively. The two cities are the most susceptible to damage from a destructive future earthquake because they are located over the tectonically active Dead Sea transform fault (DST) that is the source of most of the major historical earthquakes in the region. The largest twentieth century earthquake on the DST, the magnitude Mw 7.2 Nuweiba earthquake of November 22, 1995, caused damage to structures in both cities. The integration of geological, geophysical, and earthquake engineering studies will help to assess the seismic hazards by determining the location and slip potential of active faults and by mapping areas of high liquefaction susceptibility. Ground Penetrating Radar (GPR) as a high resolution shallow geophysical tool was used to map the shallow active faults in Aqaba, Taba Sabkha area, and Elat. The GPR data revealed the onshore continuation of the Evrona, West Aqaba, Aqaba fault zones, and several transverse faults. The integration of offshore and onshore data confirm the extension of these faults along both sides of the Gulf of Aqaba. A 3D model of GPR data at one site in Aqaba indicates that the NW-trending transverse faults right laterally offset older than NE-trending faults. The most hazardous fault is the Evrona fault which extends north to the Tabs Sabkha. A geographic information system (GIS) database of the seismic hazard was created in order to facilitate the analyzing, manipulation, and updating of the input parameters. Liquefaction potential maps were created for the region based on analysis of borehole data. The liquefaction map shows high and moderate liquefaction susceptibility zones along the northern coast of the Gulf of Aqaba. In Aqaba several hotels are located within a high and moderate liquefaction zones. The Yacht Club, Aqaba, Ayla archaeological site, and a part of commercial area are also situated in a risk area. A part

  10. Behavior and trends for Zn in Saronikos Gulf

    Directory of Open Access Journals (Sweden)

    Chalkiadakis O.

    2013-04-01

    Full Text Available The study of Zn in the water column of Saronikos Gulf in Greece during a two year period between 2008 and 2010 added data to the available time series of metal data for this marine area since 1985. The Saronikos Gulf, is directly influenced by the Athens metropolitan area. The operation of the Wastewater Treatment Plant of Athens situated on the small island of Psitalia, in 1995, was considered to be the turning point in the efforts of de-pollution of the gulf. Major sources of pollution for the gulf include also the port of Piraeus, with intensive navigation and shipping activities and the significant industrial activity occurring along the coast of Attica. This study of dissolved and particulate Zn gave results consistent with previous studies of the area such as the prevalence of the dissolved form of Zn and the most affected areas being the smaller most enclosed Gulf of Elefsina and Psitalia Island near the wastewater outfall. However, the concentrations of Zn were below toxic levels for marine aquatic organisms. Furthermore, a clear decrease in the Eastern part of the gulf was exhibited as well as a more subtle decrease in the gulf of Elefsina. The levels of Zn in Saronikos Gulf were found comparable to those of other Greek coastal areas.

  11. Sediment dispersal in the macro tidal Gulf of Kachchh, India

    Digital Repository Service at National Institute of Oceanography (India)

    Chauhan, O.S.

    of the inner gulf is marked with U and V shaped cuttings extending in the parallel clays, deposited in an earlier phase of deposition. In the outer gulf, there exists a palaeo-channel, buried under 18 m thick sediments (in the central region). Existence...

  12. Rapid evolution of a Gulf Stream warm-core ring

    Science.gov (United States)

    Joyce, T.; Backus, R.; Cowles, T.; Baker, K.; Blackwelder, P.; Brown, O.; Evans, R.; Olson, D.; Fryxell, G.; Mountain, D.

    1984-01-01

    Satellite images are used to show that major alterations in the structure of Gulf Stream warm-core rings can occur during very short periods of two to five days when an interaction with the Gulf Stream is particularly intense. The role of these interactions in the evolution of a ring are discussed.

  13. 78 FR 28292 - Gulf War Veterans' Illnesses Task Force

    Science.gov (United States)

    2013-05-14

    ... AFFAIRS Gulf War Veterans' Illnesses Task Force AGENCY: Department of Veterans Affairs (VA). ACTION... the Gulf War Veterans' Illnesses Task Force (GWVI-TF) in August 2009 to conduct a comprehensive review... War Veterans' Illnesses Task Force Draft Written Report is now complete. VA is inviting...

  14. 76 FR 65321 - Gulf War Veterans' Illnesses Task Force

    Science.gov (United States)

    2011-10-20

    ... AFFAIRS Gulf War Veterans' Illnesses Task Force AGENCY: Department of Veterans Affairs (VA). ACTION... the Gulf War Veterans' Illnesses Task Force (GWVI-TF) in August 2009 to conduct a comprehensive review... War Veterans' Illnesses Task Force Draft Written Report is now complete. VA is inviting...

  15. 75 FR 16577 - Gulf War Veterans' Illnesses Task Force

    Science.gov (United States)

    2010-04-01

    ... AFFAIRS Gulf War Veterans' Illnesses Task Force AGENCY: Department of Veterans Affairs (VA). ACTION... the Gulf War Veterans' Illnesses Task Force (GWVI-TF) in August 2009 to conduct a comprehensive review... Veterans' Illnesses Task Force Draft Written Report is now complete. The VA is inviting public comments...

  16. An American Honors Program in the Arab Gulf

    Science.gov (United States)

    Yyelland, Byrad

    2012-01-01

    The first Western honors program to be established in the Arab Gulf is offered in Doha, Qatar, on a small satellite campus of an American university. Doha is the capital city of Qatar, a sovereign Arab state physically located on a small peninsula bordering Saudi Arabia in the south and jutting into the Persian Gulf. With a population of only 1.7…

  17. Geodynamics of the Gulf of California from surface wave tomography

    NARCIS (Netherlands)

    Zhang, X.; Paulssen, H.

    2012-01-01

    The Gulf of California, which forms part of the Pacific-North American plate boundary, is an ideal place to investigate upper mantle dynamics in a continental rifting area. With 19 seismic stations located around the gulf, the NARS-Baja experiment (2002-2008) was designed to image its crustal and

  18. Geodynamics of the Gulf of California from surface wave tomography

    NARCIS (Netherlands)

    Zhang, X.; Paulssen, H.

    2012-01-01

    The Gulf of California, which forms part of the Pacific–North American plate boundary, is an ideal place to investigate upper mantle dynamics in a continental rifting area. With 19 seismic stations located around the gulf, the NARS-Baja experiment (2002–2008) was designed to image its crustal and ma

  19. Geodynamics of the Gulf of California from surface wave tomography

    NARCIS (Netherlands)

    Zhang, X.; Paulssen, H.

    2012-01-01

    The Gulf of California, which forms part of the Pacific-North American plate boundary, is an ideal place to investigate upper mantle dynamics in a continental rifting area. With 19 seismic stations located around the gulf, the NARS-Baja experiment (2002-2008) was designed to image its crustal and ma

  20. Gulf Stream marine hydrokinetic energy resource characterization off Cape Hatteras, North Carolina

    Science.gov (United States)

    Muglia, M.; He, R.; Lowcher, C.; Bane, J.; Gong, Y.; Taylor, P.

    2015-12-01

    The Gulf Stream off North Carolina has current velocities that approach 3 m/s and an average volume transport of 90 Sv (1 Sv= 106 m3/s) off of Cape Hatteras, making it the most abundant MHK (Marine Hydrokinetic Energy) resource for the state. Resource availability at a specific location depends primarily on the variability in Gulf Stream position, which is least offshore of Cape Hatteras after the stream exits the Florida Straits. Proximity to land and high current velocities in relatively shallow waters on the shelf slope make this an optimal location to quantify the MHK energy resource for NC. 3.5 years of current measurements beginning in August of 2013 from a moored 150 kHz ADCP (Acoustic Doppler Current Profiler) at an optimal location for energy extraction quantify the available energy resource and its variability, and establish the skill of a Mid-Atlantic Bight and South Atlantic Bight Regional Ocean Model in predicting the MHK energy resource. The model agrees well with long-term observed current averages and with weekly to monthly fluctuations in the current speeds. Model and observations over the first 9 months of the ADCP deployment period both averaged 1.15 m/s thirty meters below the surface. The model under estimates observed current speeds for the higher frequency current fluctuations of days to weeks. Comparisons between the model and ADCP observed currents, and velocity derived power density over the entire 3.5 years of observations demonstrate the significant inter-annual variability in power density. Shipboard 300 kHz ADCP cross-stream transects and hourly surface currents measurements off Cape Hatteras from a network of land based HF (high frequency) radars further quantify available MHK energy and assess model skill. Cross-stream transects were made with a vessel-mounted 300 kHz ADCP on a line from the 100-1000m isobaths, and measured currents in the top 100m. These measurements demonstrate the variability in the resource with water depth, and

  1. Gulf of Mexico circulation within a high-resolution numerical simulation of the North Atlantic Ocean

    Science.gov (United States)

    Romanou, Anastasia; Chassignet, Eric P.; Sturges, Wilton

    2004-01-01

    The Gulf of Mexico circulation is examined from the results of a high-resolution (1/12°) North Atlantic simulation using the Miami Isopycnic Coordinate Ocean Model. The motivation for this paper is twofold: first, we validate the model's performance in the Gulf of Mexico by comparing the model fields to past and recent observations, and second, given the good agreement with the observed Gulf of Mexico surface circulation and Loop Current variability, we expand the discussion and analysis of the model circulation to areas that have not been extensively observed/analyzed, such as the vertical structure of the Loop Current and associated eddies, especially the deep circulation below 1500 m. The interval between successive model eddy sheddings is 3 to 15 months, the eddy diameters range between 140 and 500 km, the life span is about 1 year, and the translational speeds are 2-3 km d-1, in good agreement with observations. Areas of high cyclonic eddy occurrence in the model are southwest of Florida, the Loop Current boundary, and the western Campeche Bay area. The cyclonic eddy diameters range between 50 and 375 km, the orbital speeds range between 1 and 55 cm s-1, the translational speeds range between 0.5 and 14 km d-1, and the eddy life spans range between 1 and 3 months. The vertical structure of the temperature and salinity of each modeled eddy, from the moment it is shed until it disintegrates in the western Gulf of Mexico, is in agreement with the few available observations. Below 1500 m, deep cyclonic eddies are associated with the surface Loop Current anticyclones. The eddy variability is consistent with Rossby waves propagating westward, and there is bottom intensification of the flow close to steep topography. Overall, we show that this very high horizontal resolution isopycnic coordinate ocean model, which is able to produce a quite realistic surface circulation for the North and equatorial Atlantic, is also able to reproduce well the smaller-scale, basin

  2. Marine organisms as heavy metal bioindicators in the Persian Gulf and the Gulf of Oman.

    Science.gov (United States)

    Amoozadeh, E; Malek, M; Rashidinejad, R; Nabavi, S; Karbassi, M; Ghayoumi, R; Ghorbanzadeh-Zafarani, G; Salehi, H; Sures, B

    2014-02-01

    In the present study, cadmium and lead concentrations were compared in barnacles, ghost shrimps, polychaetes, bivalves, and sediment from ten different locations along the intertidal zone of the Persian Gulf and the Gulf of Oman. The results revealed significant differences in the heavy metal concentrations between the organisms with barnacles showing, by far, the highest metal concentrations. The bioaccumulation factor of Cd in different animals follows this pattern with barnacles>bivalves>polychaetes>ghost shrimps, while the pattern for Pb was barnacles>polychaetes>bivalves>ghost shrimps. In most of the stations, sediments showed the lowest lead and cadmium concentrations. Therefore, it is concluded that barnacles with Pb concentrations between 0.17 and 2,016.1 μg/g and Cd concentrations ranging from 0.4 to 147.1 μg/g are the best organisms to be employed in monitoring programs designed to assess pollution with bioavailable metals in the Persian Gulf and the Gulf of Oman.

  3. Gulf Stream Ring Coalescence with the Gulf Stream off Cape Hatteras.

    Science.gov (United States)

    Watts, D R; Olson, D B

    1978-12-01

    A cyclonic ring, which had separated from the Gulf Stream 7 months earlier and traveled 500 kilometers westward, collided with the stream in September 1977. Within 3 days the ring and stream joined to form a sharp S-shaped meander. Shipboard expendable temperature probes and four bottom-moored inverted echo sounders were used to obtain synoptic descriptions of the rejoining process.

  4. Gulf of Mexico hurricane wave simulations using SWAN: Bulk formula-based drag coefficient sensitivity for Hurricane Ike

    NARCIS (Netherlands)

    Huang, Y.; Weisberg, R.H.; Zheng, L.; Zijlema, M.

    2013-01-01

    The effects of wind input parameterizations on wave estimations under hurricane conditions are examined using the unstructured grid, third-generation wave model, Simulating WAves Nearshore (SWAN). Experiments using Hurricane Ike wind forcing, which impacted the Gulf of Mexico in 2008, illustrate tha

  5. Gulf of Mexico hurricane wave simulations using SWAN: Bulk formula-based drag coefficient sensitivity for Hurricane Ike

    NARCIS (Netherlands)

    Huang, Y.; Weisberg, R.H.; Zheng, L.; Zijlema, M.

    2013-01-01

    The effects of wind input parameterizations on wave estimations under hurricane conditions are examined using the unstructured grid, third-generation wave model, Simulating WAves Nearshore (SWAN). Experiments using Hurricane Ike wind forcing, which impacted the Gulf of Mexico in 2008, illustrate tha

  6. 78 FR 3408 - Notice of Intent to Prepare a Supplement to the Gulf of Alaska Navy Training Activities...

    Science.gov (United States)

    2013-01-16

    ... Department of the Navy Notice of Intent to Prepare a Supplement to the Gulf of Alaska Navy Training... Training Activities Environmental Impact Statement (EIS)/ Overseas Environmental Impact Statement (OEIS.../OEIS will also analyze data using an acoustic model not available for the 2011 EIS/OEIS, the Navy...

  7. Elementary Teachers' Perceptions of Response to Intervention and Teacher Support Team Effectiveness within a Mississippi Gulf Coast School District

    Science.gov (United States)

    Rhodes, Shanta Dannette

    2014-01-01

    The purpose of this study was to examine elementary teachers' perceptions of the effectiveness of Response to Intervention (RTI) and Teacher Support Team (TST) within a Mississippi Gulf Coast school district. RTI models have gained popularity within the national education system. Schools are encouraged to implement RTI in efforts to improve the…

  8. Gulf of Mexico hurricane wave simulations using SWAN: Bulk formula-based drag coefficient sensitivity for Hurricane Ike

    NARCIS (Netherlands)

    Huang, Y.; Weisberg, R.H.; Zheng, L.; Zijlema, M.

    2013-01-01

    The effects of wind input parameterizations on wave estimations under hurricane conditions are examined using the unstructured grid, third-generation wave model, Simulating WAves Nearshore (SWAN). Experiments using Hurricane Ike wind forcing, which impacted the Gulf of Mexico in 2008, illustrate

  9. Formation of Continental Fragments: The Tamayo Bank, Gulf of California

    Science.gov (United States)

    van Wijk, J.; Abera, R.; Axen, G. J.

    2015-12-01

    Potential field data are used to construct a two-dimensional crustal model along a profile through the Tamayo Trough and Bank in the Gulf of California. The model is constrained by seismic reflection and refraction data, and field observations. The potential field data do not fit a model where the crust of the Tamayo trough is continental, but they fit well with a model where the Tamayo trough crust is oceanic. This implies that the Tamayo Bank is entirely bounded by oceanic crust and is a microcontinent. The oceanic crust of the Tamayo trough that separates the Tamayo Bank from the mainland of Mexico is thin (~4 km), so oceanic spreading was probably magma-starved before it ceased. This led us to come up with a model that explains the formation of microcontinents that are smaller in size and are not found in the proximity of hotspots. At first, seafloor spreading commences following continental breakup. When the magma supply to the ridge slows down, the plate boundary strengthens. Hence, the ridge may be abandoned while tectonic extension begins elsewhere, or slow spreading may continue while a new ridge starts to develop. The old spreading ridge becomes extinct. An asymmetric ocean basin forms if the ridge jumps within oceanic lithosphere; a microcontinent forms if the ridge jumps into a continental margin. This model for formation of continental fragments is applicable to other regions as well, eliminating the need of mantle plume impingement to facilitate rifting of a young continental margin and microcontinent formation.

  10. Estimating occurrence and detection probabilities for stream-breeding salamanders in the Gulf Coastal Plain

    Science.gov (United States)

    Lamb, Jennifer Y.; Waddle, J. Hardin; Qualls, Carl P.

    2017-01-01

    Large gaps exist in our knowledge of the ecology of stream-breeding plethodontid salamanders in the Gulf Coastal Plain. Data describing where these salamanders are likely to occur along environmental gradients, as well as their likelihood of detection, are important for the prevention and management of amphibian declines. We used presence/absence data from leaf litter bag surveys and a hierarchical Bayesian multispecies single-season occupancy model to estimate the occurrence of five species of plethodontids across reaches in headwater streams in the Gulf Coastal Plain. Average detection probabilities were high (range = 0.432–0.942) and unaffected by sampling covariates specific to the use of litter bags (i.e., bag submergence, sampling season, in-stream cover). Estimates of occurrence probabilities differed substantially between species (range = 0.092–0.703) and were influenced by the size of the upstream drainage area and by the maximum proportion of the reach that dried. The effects of these two factors were not equivalent across species. Our results demonstrate that hierarchical multispecies models successfully estimate occurrence parameters for both rare and common stream-breeding plethodontids. The resulting models clarify how species are distributed within stream networks, and they provide baseline values that will be useful in evaluating the conservation statuses of plethodontid species within lotic systems in the Gulf Coastal Plain.

  11. Study on Issues Concerning Regional Intergovernmental Cooperative Governance in Guangxi Beibu Gulf Economic Zone

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Guangxi Beibu Gulf Economic Zone has taken the initiative to explore how to promote public administration of interregional local governments and achieved some success in recent years. However, there are still many problems as follows: the cooperation never goes deep;the cooperative governance is devoid of necessary system guarantee and information exchange and share platform. We analyse the status quo of cooperation in regional intergovernmental public administration as follows: it integrates the hierarchy power of government; it sponsors the forum for strengthening public administration and deepening cooperation in Beibu Gulf Economic Zone; it accelerates regional transportation system building; it sets up public administration institution; it quickens the pace of innovation of management and system in Beibu Gulf Economic Zone. Finally we put forward the path to construction of regional government cooperative governance so as to promote sustainable regional development as follows: construct the composite regional administrative cooperative governance model; construct the regional administrative network organization governance model; construct regional administrative special-project-based intergovernmental cooperative governance model; construct long-term flexible regional administrative cooperative mechanism.

  12. NASA Earth Observations Track the Gulf Oil Spill

    Science.gov (United States)

    Jones, Jason B.; Childs, Lauren

    2010-01-01

    The NASA Applied Sciences Program created the Gulf of Mexico Initiative (GOMI) in 2007 "to enhance the region s ability to recover from the devastating hurricanes of 2005 and to address its coastal management issues going into the future." The GOMI utilizes NASA Earth science assets to address regional priorities defined by the Gulf of Mexico Alliance, a partnership formed by the states of Alabama, Florida, Louisiana, Mississippi, and Texas, along with 13 federal agencies and 4 regional organizations to promote regional collaboration and enhance the ecological and economic health of the Gulf of Mexico. NASA's GOMI is managed by the Applied Science and Technology Project Office at Stennis Space Center and has awarded over $18 million in Gulf of Mexico research since 2008. After the Deepwater Horizon oil spill, GOMI personnel assisted members of the Gulf of Mexico Alliance with obtaining NASA remote sensing data for use in their oil spill response efforts.

  13. Evolution of the Sedimentary Basin Within the Eastern Eez Polygon at the Gulf of Mexico

    Science.gov (United States)

    Valle, S.; Mortera-Gutierrez, C. A.; Bandy, W. L.; Escobar-Briones, E. G.; Perez, D. A.

    2013-05-01

    This study shows the seafloor structures and magnetic anomalies inside the eastern EEZ polygon at the Gulf of Mexico. The objective of this study is to examine the previous hypothesis of the Gulf of Mexico opening, based on the seafloor magnetic character. Researchers from the "Instituto de Ciencias del Mar y Limnología" at UNAM, collected , multibeam bathymetric data, high-resolution seismic reflection and magnetic profiles along 37 E-W transects during two campaigns on board the UNAM vessel, BO JUSTO SIERRA, SIGSBEE-11 in 2008 and SIGSBEE-13 in 2010. Results of the bathymetry data gathered with the EM300 multibeam echo sounder (Kongsberg) and processed with the software Caraibes from IFREMER has generated a bathymetry chart of seafloor at the Eastern Polygon, and a mosaic of back-scattering images. The high-resolution seismic profiles gathered with the subbottom profiler TOPAS PS-18 (Kongsberg) provide information on the stratigraphy sediment packages across this polygon and across the deep Mississippi Canyon. The magnetic anomalies are reduced from the data gathered with a proton-precession magnetometer, G877 (GEOMETRICS). The anomalies are modeled, based on a N_S rift at the Gulf central sector. The bathymetric chart and reflectivity mosaics of SIGSBEE-11 and SIGSBEE-13 documented the smooth relief of the seabed slope toward the Gulf central sector and abrupt morphological features associated to the meanders of the Mississippi Canyon that trend to the East. The multibeam bathymetry chart shows a relief depth that goes from 2,900 to 3,400 m from north to south. Meanders are observed in the seabed within the Eastern Polygon which is related to turbidity currents from the Mississippi River, and having a trend from west to east. The relief of the canyon shows channels with widths between 400 and 1800 m, and canyon depths up to 80 m. The high-resolution seismic sections, show well defined stratigraphy packages, where clear sediment strata are interrupted by

  14. 75 FR 63786 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Reef Fish Fishery of the Gulf of...

    Science.gov (United States)

    2010-10-18

    ... proposed temporary rule that would implement interim measures to reduce overfishing of gag in the Gulf of... this proposed rule is to reduce overfishing of the gag resource in the Gulf. DATES: Written comments... prevent overfishing and achieve, on a continuing basis, the optimum yield (OY) from Federally managed...

  15. 76 FR 69136 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Reef Fish Fishery of the Gulf of...

    Science.gov (United States)

    2011-11-08

    ... rule to extend the effective date of interim measures to reduce overfishing of gag in the Gulf of... extends the interim measures implemented to reduce overfishing of gag in the Gulf by reducing the... Management Council (Council). The intended effect of this rule is to reduce overfishing of the gag...

  16. 76 FR 50979 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Reef Fish Fishery of the Gulf of...

    Science.gov (United States)

    2011-08-17

    ... Resources of the Gulf of Mexico (FMP), as prepared and submitted by the Gulf of Mexico Fishery Management..., speculation, or environmental protection. As a result, prospective entities may be businesses, nonprofit..., all entities that possess a valid or renewable commercial reef fish permit are assumed to comprise the...

  17. 76 FR 78245 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Gulf of Mexico Reef Fish Fishery...

    Science.gov (United States)

    2011-12-16

    ... for the Gulf Council's Red Drum, Reef Fish, Shrimp, and Coral and Coral Reefs FMPs (Generic ACL..., and South Atlantic; Gulf of Mexico Reef Fish Fishery; South Atlantic Snapper-Grouper Fishery AGENCY... (Secretary) under section 304(f) of the Magnuson-Stevens Fishery Conservation and Management Act...

  18. 76 FR 64327 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Gulf of Mexico Reef Fish Fishery...

    Science.gov (United States)

    2011-10-18

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration RIN 0648-XA727 Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Gulf of Mexico Reef Fish Fishery; South Atlantic Snapper-Grouper Fishery...

  19. 78 FR 14983 - Fisheries of the Gulf of Mexico; Gulf of Mexico Fishery Management Council; Public Meeting

    Science.gov (United States)

    2013-03-08

    ...Independent peer review of Gulf of Mexico Spanish Mackerel and Cobia stocks will be accomplished through written reviews because delays in completing the assessments prevented their consideration at the SEDAR 28 Review Workshop. This workshop is being held by the Gulf of Mexico Fishery Management Council to consider recommendations from the written reviews and develop recommendations for the......

  20. Three-dimensional aspects of the seasonal heat balance in the Gulf of California

    Science.gov (United States)

    Beron-Vera, F. J.; Ripa, P.

    2000-05-01

    Previously unresolved three-dimensional aspects of the time mean, as well as the annual and semiannual cycles of the heat transport, are studied in the Gulf of California using a minimal box model suggested by the hydrographic data. At the very least three horizontal domains are needed for the model: a shallow region north of the big islands, a deep region identifiable with the Ballenas Channel, and another deep region spanning the rest of the gulf south of the archipelago. Only one vertical layer is considered in the northern region, whereas two layers are taken into account in the other two regions. Out of all of the possible heat exchanges among the various boxes of the model, the least-flux-variance solution is considered. The annual mean heat entering the surface in the northern region is exported in almost equal amounts to the Ballenas Channel and the southern region. Ballenas Channel, in turn, exports heat to the southern region mainly through the lower layer, producing a transversal asymmetry of the mouthward flux into the upper layer. At the mouth the heat is exported to the Pacific Ocean largely through the upper layer. Both the annual and semiannual amplitude of the exchanges between all regions are as important as the annual average, except at the mouth of the gulf, where the semiannual component is not statistically relevant. The Pacific Ocean fluxes estimates at the annual frequency agree well with those produced by a baroclinic wave, which has been shown to explain a big deal of the thermodynamics of the gulf. The annual mean vertical flux per unit horizontal area in the Ballenas Channel is much larger than that in the southern region. This reinforces previous speculations that mixing processes in this region are very important. A depth-independent eddy diffusivity parameterization suggests that diffusion might not be invoked to explain the annual mean vertical flux in the Ballenas Channel.

  1. Forecasting CO2 emissions in the Persian Gulf States

    Directory of Open Access Journals (Sweden)

    F.A. Olabemiwo

    2017-12-01

    Full Text Available The Persian Gulf States (Bahrain. Iran, Iraq, Qatar, Saudi Arabia, Kuwait and United Arab Emirate have dominated the oil and gas sector since the discovery of oil in the region. They are the world largest producers of crude oil, producing about 35 and 25 percent of the world natural gas and crude oil respectively. The use of fossil fuels is directly linked to the release of CO2 into the environment. CO2 accounts for 58.8 percent of all greenhouse gases released via human activities, consequently, presenting a malign impact on the environment through climate change, global warming, biodiversity, acid rain and desertification among others. Due to its importance, the data on CO2 emission obtained from US EIA from 1980 – 2010 was regressed using least square techniques and projections were made to the year 2050. Results indicated that each country’s p-value was less than 0.05 which implies that the models can be used for predicting CO2 emissions into the future. The data shows the emission of CO2 by countries from the highest to the lowest in 2016 as: Iran (590.72 Mtonnes; 7.58 tonnes of CO2/person > Saudi Arabia (471.82 Mtonnes; 18 tonnes of CO2/person > UAE (218.58 Mtonnes; 41.31 tonnes of CO2/person > Iraq (114.01 Mtonees; 3.71 tonnes of CO2/person > Kuwait (92.58 Mtonnes; 36.31 tonnes of CO2/person > Qatar (68.26 Mtonnes; 37 tonnes of CO2/person > Bahrain (33.16 Mtonnes; 27.5 tonnes of CO2/person". The sequence from the country with highest emission (Iran to the country with lowest emission (Bahrain will remain the same until 2050. A projection depicting a 7.7 percent yearly increase in CO2 emission in the Persian Gulf States.

  2. Migrant workers: victims of war in Gulf.

    Science.gov (United States)

    1992-01-01

    The Persian Gulf War forced millions of migrant workers in the region to return home, causing hardship not only on the workers but also on their home countries. Prior to the war, the region's oil wealth had attracted migrants from around the world. By 1990, some 3 million resided in Iraq and Kuwait alone. Many more worked in other Gulf countries. But only 2 months after the Iraqi invasion of Kuwait, over 2 million workers had fled the region or had been returned home. Yemenis and Egyptians alone accounted for 750,000 and 1/2 million workers, respectively. There were also an estimated 600,000 Asians. Although many of the migrants were unskilled laborers, many also were skilled laborers and professionals. Jordanians and Palestinians made up much of the Kuwaiti civil service. As the war unfolded, it became clear that the migrant workers lacked any of the legal rights and protection granted to other citizens. Many workers were not allowed to return home because of their importance to the economy. Others, like some 35,000 Sri Lankan housemaids in Kuwait, were stranded in the war zone, lacking the money and means to return home. In most cases, the workers also suffered from frozen bank accounts, unpaid wages and benefits, and property loss. Their return home also created problems for their countries. Jordan's population increased by 10% in 1990 due to the returning population. Yemen's unemployment increased from 10% to 25%. As a result of the Gulf war experience, the UN General Assembly adopted the International Convention on the Rights of Migrant Workers and their Families, which must now be ratified by 20 nations before implementation begins.

  3. Satellite views of the massive algal bloom in the Persian Gulf and the Gulf of Oman during 2008-2009

    Science.gov (United States)

    Yu, Shujie; Gong, Fang; He, Xianqiang; Bai, Yan; Zhu, Qiankun; Wang, Difeng; Chen, Peng

    2016-10-01

    The Persian Gulf and the Gulf of Oman locate at the northwest of the Arabian Sea, with the total area more than 50,0000 km2. The Persian Gulf is a semi-enclosed subtropical sea with high water temperature, extremely high salinity, and an average depth of 50 meters. By the Strait of Hormuz, the Persian Gulf is connected to the Gulf of Oman which is significantly affected by the monsoonal winds and by water exchange between the Arabian Sea and the Persian Gulf. Algal blooms occurred frequently in the Persian Gulf and the Gulf of Oman, and some of them are harmful algal blooms which may lead to massive fish death and thereby serious economic loss. Due to the widely spatial coverage and temporal variation, it is difficult to monitoring the dynamic of the algal bloom based on in situ measurement. In this study, we used the remote sensing data from the Moderate Resolution Imaging Spectroradiometer (MODIS) onboard the Aqua satellite to investigate a massive algal bloom event in the Persian Gulf and the Gulf of Oman during 2008-2009. The time series of MODIS-derived chlorophyll concentration (Chl-a) indicated that the bloom event with high Chl-a concentration ( 60 percent higher than corresponding climatological data) appeared to lasting more than 8 months from autumn of 2008 to spring of 2009. In addition, the bloom was widespread from the Persian Gulf to the Gulf of Oman and neighboring open ocean. The MODIS-derived net primary production (NPP) collected from MODIS showed the same trend with Chl-a. Multiple forces including upwelling, dust deposition was taken into account to elucidate the mechanisms for the long-lasting algal bloom. The time series chlorophyll concentration of the Persian Gulf emerges a significant seasonal pattern with maximum concentrations seen during the winter time and lowest during the summer. It also indicated slight disturbances occurred in June (May/July) and December (November/ January) in some years. The sea surface temperature and water

  4. Lithospheric studies along seismic profile KOKKY, between Gulf of Bothnia and Gulf of Finland, Baltic Shield

    Science.gov (United States)

    Tiira, Timo; Skrzynik, Tymon; Janik, Tomasz; Komminaho, Kari; Väkevä, Sakari; Korja, Annakaisa

    2017-04-01

    Controlled source seismology is one of the main tools used in Earth imaging, especially when aiming towards the middle and lower crust structures, Moho shape and upper mantle. Data for such studies are acquired during wide-angle reflection and refraction (WARR) profiles, which are hundreds of kilometers long and require strong explosive sources like e.g. TNT. Given the cost of such experiments, difficult logistics, and the strict regulation on experiments involving explosives in the ground, an attempt was made to register quarry blasts along the set profile. Quarries consume tons of explosive material per week and their utility in crustal studies was already tested during HUKKA experiment in 2007. Profile KOKKY begins on the coast of Bothnian Bay and runs south-east towards Sankt Petersburg in Russia. It crosses three main geological units of southern Finland, Pohjanmaa area, Central Finland Granitoid Complex, and Saimaa area, all represented by Late Proterozoic rocks. Two summer acquisition campaigns resulted in nearly 500 km long profile, crossing southern Finland. Numerous explosions from quarries were recorded, resulting in 63 usable seismic sections. Average distance between shots and the profile was 14 km. The velocity model has high P wave velocities across the entire profile. Upper crust, reaching depths of 22 km, is characterized by velocities from 5.9-6.2 km/s near surface down to 6.25-6.4 km/s. Middle crust is thinning from 30 km at NW, down to 14 km in the central part of the profile, thickening again to 20 km at SE, and has uniformed velocities 6.6-6.8 km/s. High, homogeneous velocities in lower crust, up to 7.4 km/s. Layer is thickening from 4 km in SE part of the profile, reaching 18 km in its central part corresponding to CFGC, and then thinning again to about 12 km in NW part. Moho depth varies from 54 km near the Gulf of Bothnia to 63 km in the middle of the profile, and up to 43 km in Saimaa area. Velocities below the crust are 8.2-8.25 km

  5. Steerable system adds precision to Gulf drilling

    Energy Technology Data Exchange (ETDEWEB)

    Bierschwale, H.; Ridley, R.

    1988-05-02

    A well bore intersection was achieved ahead of schedule with a steerable drilling system in the Gulf of Mexico. A computer-generated proximity survey comparing the directional surveys of the initial and replacement wells, confirmed that the wells were within 1 ft. of each other near the planned intersection depth of 8,890 ft. All objectives for the 9,050-ft. replacement well were accomplished 4 days ahead of schedule. This operation illustrates the effectiveness of the steerable drilling system for obtaining better directional control, increased drilling efficiently, and reduced overall drilling time. This article explains how the project was completed.

  6. The July 1990 Gulf Stream Experiment

    Science.gov (United States)

    Valenzuela, G. R.; Mied, R. P.; Ochadlick, A. R.; Kobrick, M.; Smith, P. M.; Askari, F.; Lai, R. J.; Sheres, D.; Morrison, J. M.; Beal, R. C.

    1991-01-01

    The specific scientific tasks addressed in the July 1990 Gulf Stream (GS) experiment were the following: (1) Kelvin wake behavior across fronts at various ship speeds, (2) the physics of temperature front/radar cross section (RCS) mismatch, (3) wave-current interactions in curvature fronts, and (4) the hydrodynamic structure and origin of synthetic-aperture-radar (SAR) slick-like features. Overall, the GS Experiment was most successful, and about 60 percent of the planned data was collected. On-going efforts concentrate on the analysis and interpretation of the data. An overview of the experiment and preliminary results of the data analysis are given.

  7. Lithospheric radial anisotropy beneath the Gulf of Mexico

    Science.gov (United States)

    Chu, Risheng; Ko, Justin Yen-Ting; Wei, Shengji; Zhan, Zhongwen; Helmberger, Don

    2017-05-01

    The Lithosphere-Asthenosphere Boundary (LAB), where a layer of low viscosity asthenosphere decouples with the upper plate motion, plays an essential role in plate tectonics. Most dynamic modeling assumes that the shear velocity can be used as a surrogate for viscosity which provides key information about mantle flow. Here, we derive a shear velocity model for the LAB structure beneath the Gulf of Mexico allowing a detailed comparison with that beneath the Pacific (PAC) and Atlantic (ATL). Our study takes advantage of the USArray data from the March 25th, 2013 Guatemala earthquake at a depth of 200 km. Such data is unique in that we can observe a direct upward traveling lid arrival which remains the first arrival ahead of the triplications beyond 18°. This extra feature in conjunction with upper-mantle triplication sampling allows good depth control of the LAB and a new upper-mantle seismic model ATM, a modification of ATL, to be developed. ATM has a prominent low velocity zone similar to the structure beneath the western Atlantic. The model contains strong radial anisotropy in the lid where VSH is about 6% faster than VSV. This anisotropic feature ends at the bottom of the lithosphere at about the depth of 175 km in contrast to the Pacific where it extends to over 300 km. Another important feature of ATM is the weaker velocity gradient from the depth of 175 to 350 km compared to Pacific models, which may be related to differences in mantle flow.

  8. Radionuclide activities, geochemistry, and accumulation rates of sediments in the Gulf of Thailand

    Science.gov (United States)

    Srisuksawad, Kanitha; Porntepkasemsan, Boonsom; Nouchpramool, Sunun; Yamkate, Pathom; Carpenter, Roy; Peterson, Michael L.; Hamilton, Terry

    1997-07-01

    Downcore concentration profiles of 210Pb, U, and Th isotopes, Al, Fe, Ti, Mn and Sc were measured in sediment box cores collected at 22 stations (16-70 m water depth) covering most of the Thai zone of the Gulf of Thailand. Distributions of excess 210Pb and the detrital elements were used to study spatial variations in sedimentary processes, mineralogy, and geochemistry between different regions of the gulf. Steady-state depositional concentrations and fluxes of excess 210Pb are 3-10 times lower in Gulf of Thailand sediments than in sediments from mid-latitudes in the northern hemisphere, reflecting lower 210Pb inputs from atmospheric fallout at 6-13°N latitude and from lower production of 210Pb from 226Ra in the shallower waters of the Gulf. U and Th concentrations are approximately 2-3 times higher than those in shelf sediments from mid-latitudes of North America, consistent with a higher proportion of granitic source rocks in the Thai environment. Downcore variations in 228Th/ 232Th activity ratios and in U activities reveal that exchange of interstitial and overlying waters and their dissolved chemicals occurs down to 20 cm in 8 of 10 cores. This benthic exchange may be important in budgets of fluxes of other soluble chemicals in this shallow shelf sea. A net flux of U isotopes from overlying water into Gulf of Thailand sediments occurs, in contrast to their release from sediments of the tropical Amazon shelf. Detectable levels of 137Cs were found only in sediments near the mouth of the largest river, the Chao Phraya. The detrital elements 232Th, 230Th, Al, Ti, and Sc all show relatively uniform downcore concentration profiles. This supports a key assumption in calculations of sediment accumulation rates from downcore profiles of 210Pb activity, that steady-state depositional conditions exist and that basic sediment mineralogy and grain size does not change. 210Pb model derived mass accumulation rates vary between 270 and 490 mg/cm 2 per year in the upper Gulf

  9. Preliminary estimates of Gulf Stream characteristics from TOPEX data and a precise gravimetric geoid

    Science.gov (United States)

    Rapp, Richard H.; Smith, Dru A.

    1994-01-01

    TOPEX sea surface height data has been used, with a gravimetric geoid, to calculate sea surface topography across the Gulf Stream. This topography was initially computed for nine tracks on cycles 21 to 29. Due to inaccurate geoid undulations on one track, results for eight tracks are reported. The sea surface topography estimates were used to calculate parameters that describe Gulf Stream characteristics from two models of the Gulf Stream. One model was based on a Gaussian representation of the velocity while the other was a hyperbolic representation of velocity or the sea surface topography. The parameters of the Gaussian velocity model fit were a width parameter, a maximum velocity value, and the location of the maximum velocity. The parameters of the hyperbolic sea surface topography model were the width, the height jump, position, and sea surface topography at the center of the stream. Both models were used for the eight tracks and nine cycles studied. Comparisons were made between the width parameters, the maximum velocities, and the height jumps. Some of the parameter estimates were found to be highly (0.9) correlated when the hyperbolic sea surface topography fit was carried out, but such correlations were reduced for either the Gaussian velocity fits or the hyperbolic velocity model fit. A comparison of the parameters derived from 1-year TOPEX data showed good agreement with values derived by Kelly (1991) using 2.5 years of Geosat data near 38 deg N, 66 deg W longitude. Accuracy of the geoid undulations used in the calculations was of order of +/- 16 cm with the accuracy of a geoid undulation difference equal to +/- 15 cm over a 100-km line in areas with good terrestrial data coverage. This paper demonstrates that our knowledge or geoid undulations and undulation differences, in a portion of the Gulf Stream region, is sufficiently accurate to determine characteristics of the jet when used with TOPEX altimeter data. The method used here has not been shown to

  10. Preliminary estimates of Gulf Stream characteristics from TOPEX data and a precise gravimetric geoid

    Science.gov (United States)

    Rapp, Richard H.; Smith, Dru A.

    1994-01-01

    TOPEX sea surface height data has been used, with a gravimetric geoid, to calculate sea surface topography across the Gulf Stream. This topography was initially computed for nine tracks on cycles 21 to 29. Due to inaccurate geoid undulations on one track, results for eight tracks are reported. The sea surface topography estimates were used to calculate parameters that describe Gulf Stream characteristics from two models of the Gulf Stream. One model was based on a Gaussian representation of the velocity while the other was a hyperbolic representation of velocity or the sea surface topography. The parameters of the Gaussian velocity model fit were a width parameter, a maximum velocity value, and the location of the maximum velocity. The parameters of the hyperbolic sea surface topography model were the width, the height jump, position, and sea surface topography at the center of the stream. Both models were used for the eight tracks and nine cycles studied. Comparisons were made between the width parameters, the maximum velocities, and the height jumps. Some of the parameter estimates were found to be highly (0.9) correlated when the hyperbolic sea surface topography fit was carried out, but such correlations were reduced for either the Gaussian velocity fits or the hyperbolic velocity model fit. A comparison of the parameters derived from 1-year TOPEX data showed good agreement with values derived by Kelly (1991) using 2.5 years of Geosat data near 38 deg N, 66 deg W longitude. Accuracy of the geoid undulations used in the calculations was of order of +/- 16 cm with the accuracy of a geoid undulation difference equal to +/- 15 cm over a 100-km line in areas with good terrestrial data coverage. This paper demonstrates that our knowledge or geoid undulations and undulation differences, in a portion of the Gulf Stream region, is sufficiently accurate to determine characteristics of the jet when used with TOPEX altimeter data. The method used here has not been shown to

  11. [The Gulf War Syndrome twenty years on].

    Science.gov (United States)

    Auxéméry, Y

    2013-10-01

    After Operation Desert Storm which took place in Iraq from August 1990 to July 1991 involving a coalition of 35 countries and a 700,000 strong contingent of mainly American men, some associations of war veterans, the media and researchers described a new diagnostic entity: the Gulf War Syndrome (GWS). GWS seems to be a new disorder which associates a litany of functional symptoms integrating the musculoskeletal, digestive, tegumentary and neurosensory systems. The symptoms presented do not allow a syndrome already known to be considered and the aetiology of the clinical picture remains unexplained, an increasing cause for concern resulting from the extent of the phenomenon and its media coverage. It quickly appears that there is no consensus amongst the scientific community concerning a nosographic description of GWS: where can all these functional complaints arise from? Different aetiopathogenic hypotheses have been studied by the American administration who is attempting to incriminate exposure to multiple risks such as vaccines and their adjuvants, organophosphorous compounds, pyridostigmine (given to the troops for the preventive treatment of the former), impoverished uranium, and the toxic emanations from oil well fires. But despite extremely in-depth scientific investigations, 10 years after the end of the war, no objective marker of physical suffering has been retained to account for the disorders presented. It would appear that the former soldiers are in even better objective health than the civil population whereas their subjective level of health remains low. Within this symptomatic population, some authors have begun to notice that the psychological disorders appear and persist associating: asthenia, fatigability, mood decline, sleep disorders, cognitive disorders and post-traumatic stress disorder (PTSD). Within the nosological framework, does GWS cause functional disorders or somatisation? Finally, 20 years after the end of the fighting, only PTSD has

  12. Seasat altimeter observations of dynamic topography in the Gulf Stream region

    Science.gov (United States)

    Cheney, R. E.; Marsh, J. G.

    1981-01-01

    A straightforward approach to altimeter data analysis in the Gulf Stream system is presented, using a detailed geoid model to remove the gravitational component. The resulting sea surface height profiles compare remarkably well with independent oceanographic observations. Specific features such as cold rings, warm rings, and no anomaly regions are analyzed and it is shown that known positions of cyclonic and anticyclonic rings correspond with depressions and elevations, respectively, with amplitudes as large as 95 cm. The apparent fluctuation of the Gulf Stream is indicated by the results, as in the finding that on time scales of a few days, surface transport indicated by the sea surface height difference across the stream varied by nearly 30%

  13. Disaster preparation and the functioning of a hospital social work department during the Gulf War.

    Science.gov (United States)

    Ben Shahar, I

    1993-01-01

    The nature of the Gulf War and its consequences for the public at the personal and community levels, called for considerable alterations in organization and management at the Chaim Sheba Medical Center, the largest government general hospital in Israel, with constant adaptation to the changing situation. The preparations and exercises preceding the state of emergency, combined with the knowledge and experience gained in similar situations in the past, equipped the staff of the Social Work Department to function adequately and to make appropriate decisions and changes in the face of moral and ethical dilemmas, as well as immediate physical threat. This article presents the rationale for the model of intervention that guided the hospital during the Gulf War in offering services to casualty victims and their families. Also discussed are the process of developing an organizational framework and its content that meets wartime demands, and the implications for social work practice in dealing with a war crisis.

  14. Net primary productivity, upwelling and coastal currents in the Gulf of Ulloa, Baja California, Mexico

    Directory of Open Access Journals (Sweden)

    E. González-Rodríguez

    2011-09-01

    Full Text Available The Gulf of Ulloa, a highly productive area off the western coast of Baja California Peninsula, is examined for five successive years (2003–2007 by using satellite data and seasonal net primary productivity estimates obtained by a vertical generalized production model. The results clearly identify a seasonal signal of coastal upwelling in productivity estimates. Highest values occur from May to June and sometimes July. We also find influence of an equatorward coastal current able of transporting water from neighboring north upwelling areas to the Gulf of Ulloa in winter–spring. This flow contributes to increase the seasonal net primary productivity. The opposite occurs in summer, when a warm poleward current of tropical characteristics arrives to the region. Our findings reveal that such warm coastal current suppressed the productivity in the whole.

  15. Assessment of pipeline stability in the Gulf of Mexico during hurricanes using dynamic analysis

    Directory of Open Access Journals (Sweden)

    Yinghui Tian

    2015-03-01

    Full Text Available Pipelines are the critical link between major offshore oil and gas developments and the mainland. Any inadequate on-bottom stability design could result in disruption and failure, having a devastating impact on the economy and environment. Predicting the stability behavior of offshore pipelines in hurricanes is therefore vital to the assessment of both new design and existing assets. The Gulf of Mexico has a very dense network of pipeline systems constructed on the seabed. During the last two decades, the Gulf of Mexico has experienced a series of strong hurricanes, which have destroyed, disrupted and destabilized many pipelines. This paper first reviews some of these engineering cases. Following that, three case studies are retrospectively simulated using an in-house developed program. The study utilizes the offshore pipeline and hurricane details to conduct a Dynamic Lateral Stability analysis, with the results providing evidence as to the accuracy of the modeling techniques developed.

  16. Biostratigraphy and paleoecologic tolerances of Oligocene through Paleocene foraminiferal assemblages of the Gulf Coast Basin

    Energy Technology Data Exchange (ETDEWEB)

    Breard, S.Q.; Nault, M.J.; Callender, A.D. [Applied Biostratigraphix, Houston, TX (United States)

    1994-12-31

    Operationally oriented biostratigraphic and paleoecologic models are developed for Paleocene, Eocene, and Oligocene foraminifera of the Gulf Coast Basin. This paper is a companion to Breard et al. (1993), which describes models of significant paleoecologic and biostratigraphic foraminifera of the Miocene through Pleistocene of this region. Key benthic paleoenvironmental markers for particular depth zones of the Paleogene are graphically presented with updated biostratigraphic charts. Estimates of environment ranges for optimal stratigraphic utility are listed for all marker species on the biostratigraphic charts. Species depth ranges on the two biostratigraphic charts are for their zones of optimum stratigraphic utility. It is also possible to find deeper water species ranging into shallower zones in the lower bathyal to abyssal zones of the Eocene and Paleocene, where species considered characteristic of these zones range above those environments. Because relatively few wells have penetrated such deep environments in the Eocene and Paleocene, we have relied on the literature for Paleogene deep-water sections of Mexico and Trinidad to supplement our list of environmentally important species. Published material on foraminifera from deep-water Eocene and Paleocene sections penetrated in oil and gas exploration wells is almost nonexistent. Combination of data from this paper with that of Breard et al.(1993) will allow explorationists to estimate environmental tolerances for the entire Gulf Coast Cenozoic biostratigraphic column. This should serve as a predictive tool for foraminiferal studies useful in the exploration and production of oil and gas for the post-Mesozoic strata of the Gulf Coast basin and beyond.

  17. Cold Surge Activity Over the Gulf of Mexico in a Warmer Climate

    Directory of Open Access Journals (Sweden)

    Edgar Perez Perez

    2014-08-01

    Full Text Available Cold surges are a dominant feature of midlatitude tropical interaction. During the North Hemisphere (NH winter, midlatitude waves propagating from the Rocky Mountains into the Gulf of Mexico result in cold surges, also known as Nortes or Tehuantepecers, associated with severe weather over the southern part of Mexico. The magnitude of their intense surface winds, precipitation and drops in surface temperature depends on the characteristics of the midlatitude wave propagating into the tropics. The high spatial resolution (20km X 20km version of the TL959L60-AGC Model of the Meteorological Research Institute of Japan is used to examine changes in cold surge activity under the A1B greenhouse gas emission scenario for the 2080 - 2099 period. The model realistically reproduces the spatial and temporal characteristics of cold surges for the 1980 - 1989 control period. The effect of changes in baroclinicity, static stability and mean flow over North America suggest that in a warmer climate, increased cold surge activity over the Gulf of Mexico would occur. However, these systems would have shorter wavelength (higher phase speeds and shorter lifespans that could reduce the total amount of winter precipitation. The increased frequency of cold surges over the Gulf of Mexico would be a consequence of weaker baroclinicity and static stability in the lower troposphere over the cold surge genesis region, along with more dominant westerly winds, resulting from ENSO-like conditions in the atmospheric circulations over North America.

  18. Holocene development of the eastern Gulf of Finland coastal zone (Baltic Sea)

    Science.gov (United States)

    Ryabchuk, Daria; Sergeev, Alexander; Gusentsova, Tatiana; Gerasimov, Dmitry; Zhamoida, Vladimir; Amantov, Aleksey; Kulkova, Marianna; Sorokin, Peter

    2014-05-01

    In 2011-2013 geoarcheological and marine geological research of the eastern Gulf of Finland coasts and near-shore bottom were undertaken. Researches were concentrated within several key-areas (Sestroretskaya Lowland, Narva-Luga Klint Bay and southern coastal zone of the Gulf (near Bolshaya Izhora village). Study areas can provide important information about Gulf of Finland Holocene coastal development as since Ancylus time (about 10000 cal.BP). Development of numerous sand accretion forms (spits, bars, dunes) of different shape, age and genesis caused formation of lagoon systems, situated now on-land due to land uplift. Coasts of lagoons in Sestroretskaya Lowland and Narva-Luga Klint Bay were inhabited by Neolithic and Early Metal people. Analysis of coastal morphology and results of geological research (GIS relief analyses, ground penetrating radar, drilling, grain-size analyses, radiocarbon dating) and geoarcheological studies allowed to reconstruct the mechanism of large accretion bodies (bars and spits) and lagoon systems formation during last 8000 years. Geoarcheological studies carried out within eastern Gulf of Finland coasts permitted to find some features of the Neolithic - Early Metal settlements distribution. Another important features of the eastern Gulf of Finland coastal zone relief are the series of submarine terraces found in the Gulf bottom (sea water depths 10 to 2 m). Analyses of the submarine terraces morphology and geology (e.g. grain-size distribution, pollen analyses and organic matter dating) allow to suppose that several times during Holocene (including preAncylus (11000 cal.BP) and preLittorina (8500 cal.BP) regressions) the sea-water level was lower than nowadays. During the maximal stage of the Littorina transgression (7600-7200 cal. BP) several open bays connected with the Littorina Sea appeared in this area. The lagoon systems and sand accretion bodies (spits and bars) were formed during the following decreasing of the sea level. Late

  19. Gulf States and the Conflict between India and Pakistan

    Directory of Open Access Journals (Sweden)

    Zahid Shahab Ahmed

    2010-05-01

    Full Text Available Traditional cultural and economic ties between the Indian subcontinent and the Gulf region have existed for several centuries now. Strengthened further, both India and Pakistan continue to have important economic and strategic ties with the countries of the Gulf. While the Gulf region offers substantial economic advantages to both, they also have the potential to make positive interventions in the bilateral conflict between India and Pakistan. The following chapter analyses the role and position of the Gulf Arab States - in particular the member states of the Gulf Cooperation Council (GCC, and their potential in acting as a buffer for the Indo-Pak conflict. It will evaluate the official positions of the Gulf region towards various aspects of the Indo-Pak conflict. The Gulfcountries have often voiced their positions at regional and internationalforums. An additional aspect of this relationship is that the Gulf States are also members of the Organization of Islamic Conference (OIC, a pan- Islamic body which has often addressed issues of contention between India and Pakistan, particularly with respect to Kashmir. Through an academic understanding of the issues and incorporating viewpoints of experts in the area, the chapter seeks to provide fresh insights into an aspect which has the possibility of becoming a crucial incentive for peace between India and Pakistan.

  20. Phytoplankton and sediments in Gulf of Mexico

    Science.gov (United States)

    2002-01-01

    Affected both by terrestrial factors like agriculture, deforestation, and erosion, and by marine factors like salinity levels, ocean temperature and water pollution, coastal environments are the dynamic interface between land and sea. In this MODIS image from January 15, 2002, the Gulf of Mexico is awash in a mixture of phytoplankton and sediment. Tan-colored sediment is flowing out into the Gulf from the Mississippi River, whose floodplain cuts a pale, wide swath to the right of center in the image, and also from numerous smaller rivers along the Louisiana coast (center). Mixing with the sediment are the multi-colored blue and green swirls that reveal the presence of large populations of marine plants called phytoplankton. Phytoplankton populations bloom and then fade, and these cycles affect fish and mammals-including humans-higher up the food chain. Certain phytoplankton are toxic to both fish and humans, and coastal health departments must monitor ecosystems carefully, often restricting fishing or harvesting of shellfish until the blooms have subsided.

  1. Phytoplankton and sediments in Gulf of Mexico

    Science.gov (United States)

    2002-01-01

    Affected both by terrestrial factors like agriculture, deforestation, and erosion, and by marine factors like salinity levels, ocean temperature and water pollution, coastal environments are the dynamic interface between land and sea. In this MODIS image from January 15, 2002, the Gulf of Mexico is awash in a mixture of phytoplankton and sediment. Tan-colored sediment is flowing out into the Gulf from the Mississippi River, whose floodplain cuts a pale, wide swath to the right of center in the image, and also from numerous smaller rivers along the Louisiana coast (center). Mixing with the sediment are the multi-colored blue and green swirls that reveal the presence of large populations of marine plants called phytoplankton. Phytoplankton populations bloom and then fade, and these cycles affect fish and mammals-including humans-higher up the food chain. Certain phytoplankton are toxic to both fish and humans, and coastal health departments must monitor ecosystems carefully, often restricting fishing or harvesting of shellfish until the blooms have subsided.

  2. Changes in the distribution of atlantic bluefin tuna (Thunnus thynnus) in the Gulf of Maine 1979-2005.

    Science.gov (United States)

    Golet, Walter J; Galuardi, Benjamin; Cooper, Andrew B; Lutcavage, Molly E

    2013-01-01

    The Gulf of Maine, NW Atlantic Ocean, is a productive, seasonal foraging ground for Atlantic bluefin tuna (Thunnus thynnus), but commercial landings of adult size classes were up to 40% below the allocated total allowable catch between 2004 to 2008 for the rod and reel, harpoon, and purse seine categories in the Gulf of Maine. Reduction in Atlantic bluefin tuna catches in the Gulf of Maine could represent a decline in spawning stock biomass, but given wide-ranging, complex migration patterns, and high energetic requirements, an alternative hypothesis is that their dispersal patterns shifted to regions with higher prey abundance or profitability, reducing availability to U.S. fishing fleets. This study fit generalized linear models to Atlantic bluefin tuna landings data collected from fishermen's logbooks (1979-2005) as well as the distances between bluefin tuna schools and Atlantic herring (Clupeaharengus), a primary prey species, to test alternative hypotheses for observed shifts in Atlantic bluefin tuna availability in the Gulf of Maine. For the bluefin model, landings varied by day of year, latitude and longitude. The effect of latitude differed by day of year and the effect of longitude differed by year. The distances between Atlantic bluefin tuna schools and Atlantic herring schools were significantly smaller (pBank in spring and autumn surveys respectively (p<0.01, r(2)=0.24, p<0.01, r(2)=0.42). Fishermen's logbooks contributed novel spatial and temporal information towards testing these hypotheses for the bluefin tuna fishery.

  3. Trends in brain cancer mortality among U.S. Gulf War veterans: 21 year follow-up.

    Science.gov (United States)

    Barth, Shannon K; Dursa, Erin K; Bossarte, Robert M; Schneiderman, Aaron I

    2017-08-03

    Previous mortality studies of U.S. Gulf War veterans through 2000 and 2004 have shown an increased risk of brain cancer mortality among some deployed individuals. When veterans possibly exposed to environmental contaminants associated with demolition of the Khamisiyah Ammunition Storage Facility at Khamisiyah, Iraq, have been compared to contemporaneously deployed unexposed veterans, the results have suggested increased risk for mortality from brain cancer among the exposed. Brain cancer mortality risk in this cohort has not been updated since 2004. This study analyzes the risk for brain cancer mortality between 1991-2011 through two series of comparisons: U.S. Gulf War deployed and non-deployed veterans from the same era; and veterans possibly exposed to environmental contaminants at Khamisiyah compared to contemporaneously deployed but unexposed U.S. Gulf War veterans. Risk of brain cancer mortality was determined using logistic regression. Life test hazard models were created to plot comparisons of annual hazard rates. Joinpoint regression models were applied to assess trends in hazard rates for brain cancer mortality. U.S. Army veterans possibly exposed at Khamisiyah had similar rates of brain cancer mortality compared to those not possibly exposed; however, veterans possibly exposed had a higher risk of brain cancer in the time period immediately following the Gulf War. Results from these analyses suggest that veterans possibly exposed at Khamisiyah experienced different patterns of brain cancer mortality risk compared to the other groups. Published by Elsevier Ltd.

  4. MODIS-Based Mapping of Secchi Disk Depth Using a Qualitative Algorithm in the Shallow Arabian Gulf

    Directory of Open Access Journals (Sweden)

    Muna. R. Al Kaabi

    2016-05-01

    Full Text Available Regionally calibrated algorithms for water quality are strongly needed, especially for optically complex waters such as coastal areas in the Arabian Gulf. In this study, a regional qualitative algorithm was proposed to retrieve seawater transparency, with Secchi disk depth (SDD as a surrogate, in the Arabian Gulf. A two-step process was carried out, first estimating the diffuse attenuation coefficient of downwelling irradiance at 490 nm (Kd_490 from MODIS/Aqua imagery and then SDD based on empirical correlations with Kd_490. Three satellite derived Kd products were tested and assessed against a set of in situ measurements, and one from a semi-analytical algorithm based on inherent optical properties gave the best performance with a R2 of 0.62. Comparisons between the performances of SDD models developed in this study and those established in other regions indicated higher accuracy of our proposed model for the Gulf region. The potential factors causing uncertainties of the proposed algorithm were also discussed. Seasonal and inter-annual variations of SDD over the entire Gulf were demonstrated using a 14-year time series of MODIS/Aqua data from 2002 to 2015. High SDD values were generally observed in summer while low values were found in winter. Inter-annual variations of SDD did not shown any significant trend with exceptions during algal bloom outbreaks that resulted in low SDD.

  5. Predicted impacts from offshore produced water discharges on hypoxia in the Gulf of Mexico.

    Energy Technology Data Exchange (ETDEWEB)

    Bierman, V. J.; Hinz, S.C.; Justic, D.; Scavia, D.; Veil, J. A.; Satterlee, K.; Parker, M. E.; Wilson, S.; Environmental Science Division; LimnoTech.; Louisiana State Univ.; Univ of Michigan; Shell E& P Co.; Exxon Mobil Production Co.; U.S. EPA

    2008-06-01

    Summer hypoxia (dissolved oxygen < 2 mg/L) in the bottom waters of the northern Gulf of Mexico has received considerable scientific and policy attention because of potential ecological and economic impacts. This hypoxic zone forms off the Louisiana coast each summer and has increased from an average of 8,300 km{sup 2} in 1985-1992 to over 16,000 km{sup 2} in 1993-2001, reaching a record 22,000 km{sup 2} in 2002. The almost threefold increase in nitrogen load from the Mississippi River Basin (MRB) to the Gulf since the middle of the last century is the primary external driver for hypoxia. A goal of the 2001 Federal Action Plan is to reduce the 5-year running average size of the hypoxic zone to below 5,000 km{sup 2} by 2015. After the Action Plan was developed, a new question arose as to whether sources other than the MRB may also contribute significant quantities of oxygen-demanding substances. One very visible potential source is the hundreds of offshore oil and gas platforms located within or near the hypoxic zone, many of which discharge varying volumes of produced water. The objectives of this study were to assess the incremental impacts of produced water discharges on dissolved oxygen in the northern Gulf of Mexico, and to evaluate the significance of these discharges relative to loadings from the MRB. Predictive simulations were conducted with three existing models of Gulf hypoxia using produced water loads from an industry study. Scenarios were designed that addressed loading uncertainties, settleability of suspended constituents, and different assumptions on delivery locations for the produced water loads. Model results correspond to the incremental impacts of produced water loads, relative to the original model results, which included only loads from the MRB. The predicted incremental impacts of produced water loads on dissolved oxygen in the northern Gulf of Mexico from all three models were small. Even considering the predicted ranges between lower- and

  6. Ocean Observing Public-Private Collaboration to Improve Tropical Storm and Hurricane Predictions in the Gulf of Mexico

    Science.gov (United States)

    Perry, R.; Leung, P.; McCall, W.; Martin, K. M.; Howden, S. D.; Vandermeulen, R. A.; Kim, H. S. S.; Kirkpatrick, B. A.; Watson, S.; Smith, W.

    2016-02-01

    In 2008, Shell partnered with NOAA to explore opportunities for improving storm predictions in the Gulf of Mexico. Since, the collaboration has grown to include partners from Shell, NOAA National Data Buoy Center and National Center for Environmental Information, National Center for Environmental Prediction, University of Southern Mississippi, and the Gulf of Mexico Coastal Ocean Observing System. The partnership leverages complementary strengths of each collaborator to build a comprehensive and sustainable monitoring and data program to expand observing capacity and protect offshore assets and Gulf communities from storms and hurricanes. The program combines in situ and autonomous platforms with remote sensing and numerical modeling. Here we focus on profiling gliders and the benefits of a public-private partnership model for expanding regional ocean observing capacity. Shallow and deep gliders measure ocean temperature to derive ocean heat content (OHC), along with salinity, dissolved oxygen, fluorescence, and CDOM, in the central and eastern Gulf shelf and offshore. Since 2012, gliders have collected 4500+ vertical profiles and surveyed 5000+ nautical miles. Adaptive sampling and mission coordination with NCEP modelers provides specific datasets to assimilate into EMC's coupled HYCOM-HWRF model and 'connect-the-dots' between well-established Eulerian metocean measurements by obtaining (and validating) data between fixed stations (e.g. platform and buoy ADCPs) . Adaptive sampling combined with remote sensing provides satellite-derived OHC validation and the ability to sample productive coastal waters advected offshore by the Loop Current. Tracking coastal waters with remote sensing provides another verification of estimate Loop Current and eddy boundaries, as well as quantifying productivity and analyzing water quality on the Gulf coast, shelf break and offshore. Incorporating gliders demonstrates their value as tools to better protect offshore oil and gas assets

  7. A data assimilation tool for the Pagasitikos Gulf ecosystem dynamics: Methods and benefits

    KAUST Repository

    Korres, Gerasimos

    2012-06-01

    Within the framework of the European INSEA project, an advanced assimilation system has been implemented for the Pagasitikos Gulf ecosystem. The system is based on a multivariate sequential data assimilation scheme that combines satellite ocean sea color (chlorophyll-a) data with the predictions of a three-dimensional coupled physical-biochemical model of the Pagasitikos Gulf ecosystem presented in a companion paper. The hydrodynamics are solved with a very high resolution (1/100°) implementation of the Princeton Ocean Model (POM). This model is nested within a coarser resolution model of the Aegean Sea which is part of the Greek POSEIDON forecasting system. The forecast of the Aegean Sea model, itself nested and initialized from a Mediterranean implementation of POM, is also used to periodically re-initalize the Pagatisikos hydrodynamics model using variational initialization techniques. The ecosystem dynamics of Pagasitikos are tackled with a stand-alone implementation of the European Seas Ecosystem Model (ERSEM). The assimilation scheme is based on the Singular Evolutive Extended Kalman (SEEK) filter, in which the error statistics are parameterized by means of a suitable set of Empirical Orthogonal Functions (EOFs).The assimilation experiments were performed for year 2003 and additionally for a 9-month period over 2006 during which the physical model was forced with the POSEIDON-ETA 6-hour atmospheric fields. The assimilation system is validated by assessing the relevance of the system in fitting the data, the impact of the assimilation on non-observed biochemical processes and the overall quality of the forecasts. Assimilation of either GlobColour in 2003 or SeaWiFS in 2006 chlorophyll-a data enhances the identification of the ecological state of the Pagasitikos Gulf. Results, however, suggest that subsurface ecological observations are needed to improve the controllability of the ecosystem in the deep layers. © 2011 Elsevier B.V.

  8. Report A, chemical oceanographic data from the Persian Gulf and Gulf of Oman from 17 April 1972 to 17 March 1978 (NODC Accession 7900091)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile and chemical data were collected using bottle casts from NOAA Ship DELAWARE and other platforms in the Persian Gulf and Gulf of Oman from 17...

  9. Northern Gulf Littoral Initiative (NGLI), Geology and Physical Properties of Marine Sediments in the N.E. Gulf of Mexico: Data Report

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Northern Gulf Littoral Initiative (NGLI), Geology and Physical Properties of Marine Sediments in the N.E. gulf of Mexico: Data Report, was produced by the U.S....

  10. Ecologic Atlas of Benthic Foraminifera of the Gulf of Mexico

    Science.gov (United States)

    Tietjen, John H.

    Because of their importance as indicators of petroleum deposits, the benthic foraminifera of the Gulf of Mexico are one of the most intensely studied groups of animals in the world. This is especially true of the foraminifera inhabiting the shallow shelf region of the northern and eastern Gulf; much less is known about the animals of the southern shelf, continental slope, and abyssal plains. The author spent 10 years examining collections from various not well-known areas of the Gulf; this atlas is a synthesis of distributional data from approximately 4500 previously known stations, plus new information from 400 additional stations.

  11. Evidence for atmospheric carbon dioxide variability over the Gulf Stream

    Science.gov (United States)

    Bufton, J. L.

    1984-01-01

    Two airborne surveys of atmospheric carbon dioxide concentration have been conducted over the Gulf Stream off the east coast of Virginia and North Carolina on September 7-8, 1983. In situ CO2 data were acquired at an aircraft altitude of 300 m on trajectories that transcected the Gulf Stream near 36 deg N 73 deg W. Data show evidence of a CO2 concentration increase by 4 ppm to 15 ppm above the nominal atmospheric background value of 345 ppm. These enhanced values were associated with the physical location of the Gulf Stream prior to the passage of a weak cold front.

  12. SAR observations of the Gulf Stream during SWADE

    Science.gov (United States)

    Vachon, Paris W.; Liu, Antony K.; Mollo-Christensen, Erik

    1992-01-01

    The Surface Wave Dynamics Experiment (SWADE) has gathered SAR observations of the Gulf Stream that show a change in ocean surface brightness; this may be due to the effects of a change in air-sea temperature difference across the observed edge, where the boundary is defined by warm, quickly flowing Gulf Stream water and cooler, relatively stationary shelf water. The two images discussed indicate the possibility of deepening understanding of Gulf Stream front dynamics by using the abundant spatial data of SAR imagery, in conjunction with more conventional (point-like) data on hydrography and currents.

  13. Gulf Stream density structure and transport during the past millennium

    OpenAIRE

    Lund, David C.; Lynch-Stieglitz, Jean; Curry, William B.

    2006-01-01

    The Gulf Stream transports approximately 31 Sv (1 Sv = 10^6 m^3 s^(-1)) of water and 1.3 10^(15) W of heat into the North Atlantic ocean. The possibility of abrupt changes in Gulf Stream heat transport is one of the key uncertainties in predictions of climate change for the coming centuries. Given the limited length of the instrumental record, our knowledge of Gulf Stream behaviour on long timescales must rely heavily on information from geologic archives. Here we use foraminifera from a su...

  14. Intrinsic low-frequency variability of the Gulf Stream

    Science.gov (United States)

    Quattrocchi, G.; Pierini, S.; Dijkstra, H. A.

    2012-03-01

    In this paper a process study aimed at analyzing the low-frequency variability of intrinsically oceanic origin of the Gulf Stream (GS) and GS extension (GSE) is presented. An eddy-permitting reduced-gravity nonlinear shallow water model is implemented in an idealized North Atlantic Ocean, with schematic boundaries including the essential geometric features of the coastline and a realistic zonal basin width at all latitudes. The forcing is provided by a time-independent climatological surface wind stress obtained from 41 years of monthly ECMWF fields. The model response yields strong intrinsic low-frequency fluctuations on the interannual to decadal time scales. The modelled time-averaged GS/GSE flows are found to exhibit several features that can also be deduced from satellite altimeter data, such as the Florida Current seaward deflection, the GS separation at Cape Hatteras, and the overall structure of the GSE. The intrinsic low-frequency variability yields two preferred states of the GSE differing in latitudinal location that also have their counterpart in the altimeter data. A preliminary analysis of the variability in terms of dynamical systems theory is carried out by using the lateral eddy viscosity as the control parameter. A complex transition sequence from a steady state to irregular low-frequency variability emerges, in which Hopf and global bifurcations can be identified.

  15. Intrinsic low-frequency variability of the Gulf Stream

    Directory of Open Access Journals (Sweden)

    G. Quattrocchi

    2012-03-01

    Full Text Available In this paper a process study aimed at analyzing the low-frequency variability of intrinsically oceanic origin of the Gulf Stream (GS and GS extension (GSE is presented. An eddy-permitting reduced-gravity nonlinear shallow water model is implemented in an idealized North Atlantic Ocean, with schematic boundaries including the essential geometric features of the coastline and a realistic zonal basin width at all latitudes. The forcing is provided by a time-independent climatological surface wind stress obtained from 41 years of monthly ECMWF fields. The model response yields strong intrinsic low-frequency fluctuations on the interannual to decadal time scales. The modelled time-averaged GS/GSE flows are found to exhibit several features that can also be deduced from satellite altimeter data, such as the Florida Current seaward deflection, the GS separation at Cape Hatteras, and the overall structure of the GSE. The intrinsic low-frequency variability yields two preferred states of the GSE differing in latitudinal location that also have their counterpart in the altimeter data. A preliminary analysis of the variability in terms of dynamical systems theory is carried out by using the lateral eddy viscosity as the control parameter. A complex transition sequence from a steady state to irregular low-frequency variability emerges, in which Hopf and global bifurcations can be identified.

  16. HIGH COOLING WATER TEMPERATURE EFFECTS ON DESIGN AND OPERATIONAL SAFETY OF NPPS IN THE GULF REGION

    Directory of Open Access Journals (Sweden)

    BYUNG KOO KIM

    2013-12-01

    Full Text Available The Arabian Gulf region has one of the highest ocean temperatures, reaching above 35 degrees and ambient temperatures over 50 degrees in the summer. Two nuclear power plants (NPP are being introduced in the region for the first time, one at Bushehr (1,000 MWe PWR plant from Russia, and a much larger one at Barakah (4X1,400 MWe PWR from Korea. Both plants take seawater from the Gulf for condenser cooling, having to modify the secondary/tertiary side cooling systems design by increasing the heat transfer surface area from the country of origin. This paper analyses the secondary side of a typical PWR plant operating under the Rankine cycle with a simplified thermal-hydraulic model. Parametric study of ocean cooling temperatures is conducted to estimate thermal efficiency variations and its associated design changes for the secondary side. Operational safety is reviewed to deliver rated power output with acceptable safety margins in line with technical specifications, mainly in the auxiliary systems together with the cooling water temperature. Impact on the Gulf seawater as the ultimate heat sink is considered negligible, affecting only the adjacent water near the NPP site, when compared to the solar radiation on the sea surface.

  17. Coastal-trapped Motions off Southern Tamaulipas and Northern Veracruz, Western Gulf of Mexico

    Science.gov (United States)

    Rivas, D.

    2015-12-01

    Four months of observations from a near-coastal mooring deployed off southern Tamaulipas-northern Veracruz coast (western Gulf of Mexico) during winter 2012-2013 provides velocity and pressure series in a coastal region where apparently no in-situ measurements have been formally reported. The measurements show numerous events of intense alongshore velocities with magnitudes typically exceeding 80 cm/s, associated with intensified winds associated with the cold fronts invading the western Gulf during fall-winter, via coastal-trapped motions coming from northern locations. These motions induce a coastal jet that modulates the regional along-shelf transports. This notion is corroborated by an analytical coastal-trapped wave (CTW) model which explains most of the variability of the sea level and the alongshore barotropic velocity observed in the mooring, and which can also be used to estimate how much of the observed variance is generated in remote locations along the northern coast of the Gulf of Mexico.

  18. Brain Immune Interactions as the Basis of Gulf War Illness: Gulf War Illness Consortium (GWIC)

    Science.gov (United States)

    2016-10-01

    neuroimaging assessment of brain antioxidant glutathione levels (Krengel, Initiating PI; Sullivan Partnering PI; GW140140)  PON1 study with GWIC...Investigator proposal with Boston University (BU) investigators  BChE + PON1 biomarker epidemiological New Investigator proposal with BU investigators...veterans of the 1991 Gulf War potentially exposed to sarin and cyclosarin. Neurotoxicology. 28(4):761-769. http://www.ncbi.nlm.nih.gov/ pubmed /17485118 5

  19. Combining Multicomponent Seismic Attributes, New Rock Physics Models, and In Situ Data to Estimate Gas-Hydrate Concentrations in Deep-Water, Near-Seafloor Strata of the Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Bureau of Economic Geology

    2009-04-30

    The Bureau of Economic Geology was contracted to develop technologies that demonstrate the value of multicomponent seismic technology for evaluating deep-water hydrates across the Green Canyon area of the Gulf of Mexico. This report describes the methodologies that were developed to create compressional (P-P) and converted-shear (P-SV) images of near-seafloor geology from four-component ocean-bottom-cable (4C OBC) seismic data and the procedures used to integrate P-P and P-SV seismic attributes with borehole calibration data to estimate hydrate concentration across two study areas spanning 16 and 25 lease blocks (or 144 and 225 square miles), respectively. Approximately 200 km of two-dimensional 4C OBC profiles were processed and analyzed over the course of the 3-year project. The strategies we developed to image near-seafloor geology with 4C OBC data are unique, and the paper describing our methodology was peer-recognized with a Best Paper Award by the Society of Exploration Geophysicists in the first year of the project (2006). Among the valuable research findings demonstrated in this report, the demonstrated ability to image deep-water near-seafloor geology with sub-meter resolution using a standard-frequency (10-200 Hz) air gun array on the sea surface and 4C sensors on the seafloor has been the accomplishment that has received the most accolades from professional peers. Our study found that hydrate is pervasive across the two study areas that were analyzed but exists at low concentrations. Although our joint inversion technique showed that in some limited areas, and in some geologic units across those small areas, hydrates occupied up to 40-percent of the sediment pore space, we found that when hydrate was present, hydrate concentration tended to occupy only 10-percent to 20-percent of the pore volume. We also found that hydrate concentration tended to be greater near the base of the hydrate stability zone than it was within the central part of the stability

  20. Migratory corridors of adult female Kemp’s ridley turtles in the Gulf of Mexico

    Science.gov (United States)

    Shaver, Donna J.; Hart, Kristen M.; Fujisaki, Ikuko; Rubio, Cynthia; Sartain-Iverson, Autumn R.; Pena, Jaime; Gamez, Daniel Gomez; Gonzales Diaz Miron, Raul de Jesus; Burchfield, Patrick M.; Martinez, Hector J.; Ortiz, Jaime

    2016-01-01

    For many marine species, locations of migratory pathways are not well defined. We used satellite telemetry and switching state-space modeling (SSM) to define the migratory corridor used by Kemp's ridley turtles (Lepidochelys kempii) in the Gulf of Mexico. The turtles were tagged after nesting at Padre Island National Seashore, Texas, USA from 1997 to 2014 (PAIS; n = 80); Rancho Nuevo, Tamaulipas, Mexico from 2010 to 2011 (RN; n = 14); Tecolutla, Veracruz, Mexico from 2012 to 2013 (VC; n = 13); and Gulf Shores, Alabama, USA during 2012 (GS; n = 1). The migratory corridor lies in nearshore Gulf of Mexico waters in the USA and Mexico with mean water depth of 26 m and a mean distance of 20 km from the nearest mainland coast. Migration from the nesting beach is a short phenomenon that occurs from late-May through August, with a peak in June. There was spatial similarity of post-nesting migratory pathways for different turtles over a 16 year period. Thus, our results indicate that these nearshore Gulf waters represent a critical migratory habitat for this species. However, there is a gap in our understanding of the migratory pathways used by this and other species to return from foraging grounds to nesting beaches. Therefore, our results highlight the need for tracking reproductive individuals from foraging grounds to nesting beaches. Continued tracking of adult females from PAIS, RN, and VC nesting beaches will allow further study of environmental and bathymetric components of migratory habitat and threats occurring within our defined corridor. Furthermore, the existence of this migratory corridor in nearshore waters of both the USA and Mexico demonstrates that international cooperation is necessary to protect essential migratory habitat for this imperiled species.